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NOVEMBER 2016 RCCL REVIEW OF CORNEA & CONTACT LENSES TARGETING Astigmatism The Toric Toolbox P. 08 Taking Torics to the Top P. 10 Sclerals for Irregular Corneas P. 14 EARN 1 CE CREDIT Surgical Correction of Astigmatism P. 18 Supplement to Tear Film Dynamics • Scleral-induced Pingueculitis • Breaking Bad Habits • Building Your Practice The first contact lens specifically designed for your patients’ digital life and everyday living_ 9 out of 10 digital device users* agreed that Biofinity Energys™ contact lenses made their eyes feel good1. 8 out of 10 digital device users* agreed that Biofinity Energys™ contact lenses made their eyes feel less tired1. Your patients’ busy lives happen on-screen and off. Help them experience the contact lens designed for the way they live. Biofinity Energys™ contact lenses help with eye tiredness and dryness commonly associated with digital device use. Considering 90 percent of U.S. adults use digital devices more than two hours per day2, the opportunity to upgrade your patients is significant. Biofinity Energys™ contact lenses feature a revolutionary Digital Zone Optics™ lens design and Aquaform® Technology. Energize your practice—prescribe the patent-pending contact lens innovation made for today's digital lifestyle. Visit coopervision.com, or talk to your CooperVision® representative for details. Welcome to the new comfort zone_ * Among patients who use digital devices at least 4 hours per day at least 5 days per week and self-report symptoms of eye fatigue at least once per week. 1 After 1 week of wear; data on file. 2 The Vision Council. Eyes overexposed: the digital device dilemma: 2016 digital eye strain report. ©2016 CooperVision 9033O BC 7/16 RCCL0916_Coopervision Biofinity.indd 1 8/29/16 11:01 AM contents Review of Cornea & Contact Lenses | November 2016 departments 4 News Review Corneal Thickness May Help Predict CXL Outcomes; New Stats Highlight the Need for More DED Education 6 My Perspective A Look at the Androgen Connection By Joseph P. Shovlin, OD 8 The GP Experts The Toric Toolbox: Don’t Forget GPs By Robert Ensley, OD, and Heidi Miller, OD 32 Practice Progress Breaking Habits By Mile Brujic, OD, and Jason R. Miller, OD, MBA 34 Out of the Box features 10 14 18 Four Keys to Building Your Practice By Gary Gerber, OD Taking Torics to the Top Fitting toric lenses has become increasingly straightforward and now presents a viable option for myriad contact lens wearers. By David Kading, OD, and Charissa Young, OD When to Opt for Scleral Lenses Irregular cornea patients in particular can enjoy the many benefits that accompany fitting scleral lenses. By Michael J. Lipson, OD CE — Surgical Options for the Correction of Astigmatism Today’s sophisticated surgical tools and techniques offer dramatically improved outcomes over the imprecise early efforts of yesterday. By Kristen Brown, OD 24 29 Become a Fan on Facebook /ReviewofCorneaAndContactLenses Case Report: Solving Scleral Contact Lens-Induced Pingueculitis The simplest option is often the best solution. By Brian Chou, OD Advances in Understanding Tear Film Dynamics Let’s gain some perspective on the components, modalities, and methodology of dry eye. By Will Smith, OD Follow Us On Twitter @RCCLmag REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 3 News Review IN BRIEF ■ Dry eye symptoms and body fat may be correlated, a new prospective study suggests. Researchers sampled ocular symptoms and indices of adiposity in the general adult population and in the 305 participants, including 53 contact lens wearers. Results show a moderate correlation between body fat percentage and dry eye symptoms. Chronic inflammation may be the link. “Adipose tissue contributes to a rise in circulating levels of many proinflammatory mediators,” the researchers state. Ho KC, Jalbert I, Watt K, Golebiowski B. A possible association between dry eye symptoms and body fat: a prospective, cross-sectional preliminary study. Eye & Contact Lens. 2016. EPub ahead of print. ■ Keratitis infections appear to be more common in the summer, according to a new study. Researchers performed a retrospective chart review on patients presenting to the emergency department who were diagnosed with infectious keratitis from 2008 to 2013. Looking at data from 155 patients diagnosed with keratitis, researchers found that 12.3% of patients with ulcers presented in the fall, 21.3% in the spring, 21.9% in the winter and 44.5% in the summer—indicating a higher frequency of infectious keratitis and P. aeruginosa positivity during the summer months. Researchers posit that possible factors for this include warmer temperatures, higher levels of humidity and increased ocular exposure to water. Gorski M, Genis A, Yushvayev S, et al. Seasonal variation in the presentation of infectious keratitis. Eye & Contact Lens. 2016 Sep;(42(5):295-7. ■ Researchers recently developed and evaluated a new meibomian gland dysfunction (MGD)-specific questionnaire based on accepted tests such as the Schein symptom survey, tear break-up time, corneal and conjunctival staining, abnormal meibum or meibomian gland atrophy and a normal Schirmer test. The MGD questionnaire initially contained 24 items targeting the intensity and frequency of 12 symptoms. Using data from the 69 MGD subjects who completed the survey and clinical testing, researchers worked through three iterations of analysis of subject responses to the tests. The final questionnaire included seven question pairs. Researchers conclude that the study is a valid and quantitative measure of symptoms common for patients with MGD. They acknowledge that further research is needed to determine whether the diagnostic efficacy is an adequate means of differentiating MGD dry eye subtypes in an independent sample of normal subjects. Paugh JR, Kwan J, Christensen M, et al. Development of a meibomian gland dysfuntion—specific symptom questionnaire. Eye & Contact Lens. 4 Corneal Thickness May Help Predict CXL Outcomes R esearchers recently examined how preoperative characteristics impact the outcomes of corneal collagen crosslinking (CXL) in pediatric patients and found that the thinnest baseline corneal thickness impacts the success rate of CXL after two-year follow up.1 “Keratoconus has potentially devastating effects on our patients’ quality of life,” says Barry Eiden, OD, co-founder and president of the International Keratoconus Academy. “Younger individuals (<18) who develop keratoconus have been shown to progress faster and develop more advanced disease with a higher rate requiring corneal transplantation.” Research shows that collagen crosslinking can slow down or halt the progression of the degenerative disorder and, when successful, CXL may stabilize keratoconus while leading to a permanent flattening of the cornea—a result that potentially saves individuals from progressive vision loss or risky corneal transplants in the future. This study help to further identify the particular characteristics of patients who will more likely be successful candidates for this leading-edge procedure. The study included 72 eyes of 52 patients with keratoconus. The subjects were all under the age of 18 with a two-year follow up after CXL. Researchers analyzed subgroups determined by age, sex, baseline uncorrected and corrected distance visual acuities (UCVA, CDVA), topographic cone location (central and paracentral), maximum keratometry (k-max) and REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 corneal thickness at the thinnest point (thCT). Results of the study show that two years after CXL, the mean UCVA improved considerably, while the mean thCT decreased significantly in all patients. The k-max in patients with paracentral cones and/or a thCT of less than 450µm was more likely to progress. The other characteristics did not present any notable effect on the progression of CXL after treatment. “The challenge,” says Dr. Eiden, “is for us to develop metrics that reliably indicate keratoconus stability vs. progression. In this study, progression was defined as a steepening of the maximum anterior corneal curvature value (>1D) within 3mm of the apex of the cone (k-max). Other studies suggest alternative measures that may be more reliable indicators.”2 While the efficacy and safety of CXL in pediatric and adult patients have been thoroughly demonstrated, this study sheds light on factors that help predict successful outcomes for pediatric patients undergoing crosslinking. “Further research surely is needed,” suggests Dr. Eiden. “However, the take-home message continues to be the importance of early diagnosis of keratoconus and implementation of treatment methods to hopefully halt the progression of the disease prior to its significant impact on visual function.” 1. Sarac O, Caglayan M, Cakmak HB, Cagil N. Factors influencing progression of keratoconus 2 years after corneal collagen cross-linking in pediatric patients. Cornea. 2016. EPub ahead of print. 2. Duncan JK, Belin MW, Borgstrom M. Assessing progression of keratoconus: novel tomographic determinants. Eye and Vision. 2016 Mar;3(6). RCCL REVIEW OF CORNEA & CONTACT LENSES 11 Campus Blvd., Suite 100 Newtown Square, PA 19073 Telephone (610) 492-1000 Fax (610) 492-1049 Editorial inquiries: (610) 492-1006 Advertising inquiries: (610) 492-1011 Email: [email protected] EDITORIAL STAFF BUSINESS STAFF PUBLISHER James Henne [email protected] REGIONAL SALES MANAGER Michele Barrett [email protected] REGIONAL SALES MANAGER Michael Hoster [email protected] VICE PRESIDENT, OPERATIONS Casey Foster [email protected] EXECUTIVE STAFF CEO, INFORMATION SERVICES GROUP Marc Ferrara [email protected] SENIOR VICE PRESIDENT, OPERATIONS Jeff Levitz [email protected] SENIOR VICE PRESIDENT, HUMAN RESOURCES Tammy Garcia [email protected] VICE PRESIDENT, CREATIVE SERVICES & PRODUCTION Monica Tettamanzi [email protected] VICE PRESIDENT, CIRCULATION Emelda Barea [email protected] CORPORATE PRODUCTION MANAGER John Caggiano [email protected] EDITORIAL REVIEW BOARD Mark B. Abelson, MD James V. Aquavella, MD Edward S. Bennett, OD Aaron Bronner, OD Brian Chou, OD Kenneth Daniels, OD S. Barry Eiden, OD Desmond Fonn, Dip Optom M Optom Gary Gerber, OD Robert M. Grohe, OD Susan Gromacki, OD Patricia Keech, OD Bruce Koffler, MD Pete Kollbaum, OD, PhD Jeffrey Charles Krohn, OD Kenneth A. Lebow, OD Jerry Legerton, OD Kelly Nichols, OD Robert Ryan, OD Jack Schaeffer, OD Charles B. Slonim, MD Kirk Smick, OD Mary Jo Stiegemeier, OD Loretta B. Szczotka, OD Michael A. Ward, FCLSA Barry M. Weiner, OD Barry Weissman, OD N early 90% of eye care providers (ECPs) believe there is no representative type of dry eye disease (DED) patient, according to the National Eye C.A.R.E. (Current Attitudes Related to Eye Health) Survey. The online survey included more than 1,000 optometrists and ophthalmologists, as well as more than 1,200 adults who had been diagnosed with DED or experienced dry eye symptoms and used artificial tears within the past month. Results provide new statistics on many aspects of dry eye care, including: Patient demographics • 76% said they see more patients aged 18 to 34 with DED symptoms than 10 years ago. • 89% of ECPs believe DED is on the rise due to multi-screen digital device use. Screening • 94% said DED screening should be part of the comprehensive eye exam. • 75% believe it’s necessary to screen for dry eye symptoms in all patients regardless of age, gender or lifestyle. • 88% deem it important to screen women over 50. Symptoms • 79% of patients said their DED symptoms are currently under control. • 52% said their symptoms are getting worse over time. • 75% said dry eye impacts their digital device use and 64% said it impedes daily activities. • 54% said DED symptoms impact their ability to work. • 69% believe dry eye is something they have to live with. Photo: Paul M. Karpecki, OD EDITOR-IN-CHIEF Jack Persico [email protected] MANAGING EDITOR Rebecca Hepp [email protected] ASSOCIATE EDITOR Adrienne Taron [email protected] CLINICAL EDITOR Joseph P. Shovlin, OD, [email protected] ASSOCIATE CLINICAL EDITOR Christine W. Sindt, OD, [email protected] EXECUTIVE EDITOR Arthur B. Epstein, OD, [email protected] CONSULTING EDITOR Milton M. Hom, OD, [email protected] GRAPHIC DESIGNER Ashley Schmouder [email protected] AD PRODUCTION MANAGER Scott Tobin [email protected] New Stats Highlight the Need for More DED Education Dry eye is on the rise, according to a new study, and prolonged digital device use might be to blame. The survey also revealed the need for more patient education, noting that 72% of ECPs said most patients aren’t familiar with DED. Patient responses are in accord with this finding, as 25% said they didn’t realize eye dryness is a symptom of a disease, and 32% said they didn’t know DED could cause long-term damage to their eyes. Despite the well-known need for dry eye care, 72% of patients who participated in the survey said they initiated the DED conversation themselves. More telling, 45% of patients said they did not feel it was worth mentioning dry eye because the ECP did not ask about it. A rmed with these new statistics, ECPs are better equipped to address dry eye in every exam and help more patients find the relief they never knew they needed. RCCL Shire Pharmaceuticals. The National Eye C.A.R.E. (Current Attitudes Related to Eye Health) Survey. September 2016. Available at www.myeyelove-ecp. com/dry-eye-info-from-peers. Accessed October 19, 2016. Advertiser Index Bausch + Lomb ....Page 7, Cover 3 CooperVision .....................Cover 2 Menicon ............................. Cover 4 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 5 My Perspective By Joseph P. Shovlin, OD A Look at the Androgen Connection Could hormonal therapy work for dry eye? T he elaborate tear film ecosystem has to maintain its own delicate balance, despite influences from many outside sources and intrinsic characteristics. Dry eye is one such condition to disrupt the balance, giving rise to its newer moniker, dysfunctional tear film. It likely results from a host of factors, including hormone imbalance. BENEFITS AND RISKS Androgen has been shown to regulate meibomian gland function, and any dysregulation has a profoundly adverse effect. Along with microbial invasion and duct stenosis, androgen dysregulation promotes inflammation in meibomian gland dysfunction (MGD), ultimately affecting the tear film.1 Androgens also play a similar role in lacrimal gland function.2 A deficiency in androgen resulting from attenuation in androgen synthesis has been documented in Sjögren’s syndrome, menopause, aging, men taking androgen blockers and in complete androgen insensitivity syndrome.2 Multiple genes coding for androgen activity are present in ocular tissues, and research suggests androgen levels are depleted in individuals with significant MGD.1,3 Testosterone is the most common form of androgen. Dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS) and androstenedione are also referred to as androgens, though they are actually converted to testosterone and could therefore be called pre-androgens.4,5 6 Sex hormone deficiency also plays a key role in most dry eye disease, and studies have analyzed various methods for delivering androgen to the ocular surface.4 Unfortunately, investigators found topical testosterone has poor solubility and results in considerable discomfort and irritation. A transdermal orphan preparation was licensed to arGentis Pharmaceuticals, which yielded good results, as did a progesterone transdermal delivery option.3 No testosterone or progesterone preparations have yet made it to market. In addition to establishing efficacy, a major impediment for approval is safety. Commercial testosterone’s use is limited by cost, inconvenience, discomfort and occasional side effects—especially in women.3 Various reports show potential side effects for men with prostate disease and women with breast cancer (or those at high risk for each disease) when using hormone therapy. Although some theorize hormone supplementation enhances cancer growth, others reject this notion and show no association with increased risk.3 Regardless, a careful patient history is vital before initiating hormone therapy and, in men, a PSA blood draw and urologic exam is prudent. Many of the side effects and safety concerns stem from oral formulations or are secondary to increased aromatase activity, elevated estradiol and its effect at the estrogen receptor. Aromatase activity increases with age, obesity, alcohol intake, insulin resistance, breast cancer, medications, processed diet and sedentary lifestyle.4 Although often overlooked in clinical studies, monitoring aromatase activity and REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 symptoms of elevated estradiol is critical to the safe use of testosterone in both sexes. One alternative is a transdermal preparation of testosterone (3% to 10%) used once or twice daily. In addition, practitioners have used topical DHEA (.03% to 0.5%), the metabolic precursor to testosterone, from a compounding pharmacy with some reported success.3 However, results have been inconsistent, with reports of irritation. PLAY IT SAFE The significance of androgen for dry eye therapy is well established, and some of us will occasionally use it in a transdermal form, mostly with female patients. However, we await additional evidence to ensure meaningful benefit with no harm when prescribing it to more patients. Further, we need a safe and effective commercial product to provide a remedy for dry eye. Although this has been part of the discourse for nearly two decades, a dearth of studies and clinical trials remains. Some practitioners will continue to use the off-label transdermal testosterone as echelon therapy, but it’s vital that this be accompanied by close monitoring for any evidence of hormonally responsive tumors. RCCL 1. Sullivan DA, Sullivan BD, Evans JE, et al. Meibomian gland dysfunction and evaporative dry eye. Ann NY Acad Sci. 2002 June;966:211-2. 2. Sullivan DA, Yamagami H, Liu M, et al Sex steroids, the meibomian gland and evaporative dry eye. Adv Exp Med Bio. 2002;506:389-99. 3. Dawson TL. Testosterone eye drops: A novel treatment for dry eye disease. Ophthalmol Times. 2015 Nov. 4. Glaser R, Dimitrakakis C. Testosterone therapy in women: Myths and misconceptions. Maturitas. 2013;74(3):230-4. 5. Olson MC, Korb DR, Greiner JV. Evaluation of warm compress therapy for meibomian gland dysfunction. Invest Ophthalmol Vis Sci. 2003 May;44:2452. Customized Lenses When fitting irregular corneas, you have finally reached your destination. Zenlens™ Scleral Lens • Lens diameters of 16.0mm and 17.0mm enable you to fit a wide range of corneas • SmartCurve™ technology allows you to change the parameters you want, not the ones you don’t • Comprehensive 28-lens diagnostic set • Expertise from FCLSA* consultants with decades of in-office fitting experience NovaKone® Soft Lens • Dual Elliptical Stabilization™ and cylinder powers to -10.00D, to help address residual astigmatism in patients with keratoconus • Variable lens center thickness to help neutralize irregular astigmatism * Fellow of Contact Lens Society of America Your “go to” scleral lens and soft lens options can now be found in one place. Learn more about Zenlens™ and NovaKone® by calling or visiting: 800 253-3669 www.bausch.com/svp RCCL1116_BL Specialty.indd 1 10/12/16 2:49 PM The GP Experts By Robert Ensley, OD, and Heidi Miller, OD The Toric Toolbox: Don’t Forget GPs To bolster confidence, let’s review the basics of toric GP fitting. P atients often report having been told they can’t wear contact lenses because of their astigmatism. With advancements in contact lens technology, however, this is no longer the case. Major soft lens manufacturers and custom soft lens laboratories now offer extended parameter ranges, allowing even the most highly astigmatic patients to fall within a correctable range. Despite advances in soft lens technology, however, the gold standard for quality of vision is still a gas permeable (GP) lens. Research shows GP lenses provide superior vision over their soft toric lens counterparts—including for patients with moderate to high astigmatism of 2.50D or greater.1 Although fitting GP lenses for astigmatism may seem intimidating, it’s essential knowledge for contact lens practitioners. WHEN TO USE A TORIC GP The normal astigmatic cornea has two principal meridians 90 degrees apart, each with a different curvature and resultant refractive power. In combination with the tear layer underneath, a GP lens provides a spherical refracting surface to correct the astigmatism. To provide optimal comfort and vision, a GP lens should center well over the visual axis and align closely to the corneal shape. Typically, you can successfully fit a spherical GP lens on a cornea with 2.0D or less of toricity. Before placing a spherical GP lens on the eye, you should calculate 8 residual internal astigmatism, which originates from the posterior cornea and/or crystalline lens. The calculated residual astigmatism (CRA) is the difference between the total refractive astigmatism at the corneal plane and the anterior corneal astigmatism measured by keratometry. You can find actual residual This 3.0D with the rule cornea is a great candidate for astigmatism (ARA) a GP lens with back surface toricity. by subjective spherocylindrical overrefraction. with apical bearing along the flat The ARA is typically less than meridian, as well as pooling and the CRA, and simple math will edge lift along the steep meridisave chair time and frustration, as an. This misalignment can cause 0.75D or more of ARA can result several complications, including in decreased vision.2 lens rocking or flexure; decentraIn this situation, if a GP lens is tion; corneal molding and distorstill indicated or preferred by the tion; and corneal desiccation from patient over a soft toric lens, you excessive edge lift. can fit a front surface toric (FST) Although there is debate among GP lens. FST GP lenses apply the practitioners, 2.50D or more of astigmatic power on the front corneal astigmatism is a commonsurface, using prism ballasting and ly accepted threshold for using truncation to stabilize rotation. back surface toricity.3 By using two base curves (BC), one for each Similar to soft toric lenses, FST principal meridian, back surface GPs may require rotational comtoricity provides a better lens-topensation using the left add, right cornea fit. While several methsubtract (LARS) principle. ods to determine BCs exist, the As the corneal astigmatism Mandell-Moore guide is a popular increases, you should pay greater and efficient method. Using this attention to the alignment of the fit factor, the BC is 0.25D flatter GP lens to the corneal curvature. than the flat meridian and 0.50D Placing a GP lens with a spherical back surface on a highly astigmat- to 0.75D flatter than the steep meridian, depending on the amount ic cornea will create a dumbbell shaped sodium fluorescein pattern of corneal astigmatism. The lens REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 power on each meridian is then determined, using the SAM-FAP principle to account for the tear lens power. BITORIC LENSES Because of differences in the refractive index of the contact lens and the tear lens, a GP lens with back surface toricity will induce astigmatism of approximately half the magnitude of the back surface toricity. In most cases, to correct this induced astigmatism, you can add additional astigmatic power to the front surface of the lens, making the lens bitoric. Bitoric lenses are classified into two designs: spherical power effect (SPE) and cylindrical power effect (CPE). When adding astigmatic power to the front surface of the lens, you must take rotation of the lens into consideration. SPE lenses correct astigmatism similar to a spherical lens, despite having bitoric curves. Thus, the lens power is equivalent to a spherical lens and can rotate freely on the eye without impacting vision. CPE lenses must be rotationally stable to avoid inducing further astigmatism. To determine the bitoric design, you should compare both the dioptric BC difference and the back vertex power difference between the two principle meridians. If the dioptric differences between meridians are equal for both BC and back vertex power, the bitoric is an SPE design. When the dioptric differences are unequal, the lens is a CPE design—typically occurring when refractive astigmatism is unequal to corneal astigmatism. If the back vertex power is 1.5 times the back surface toricity, the induced astigmatism effectively cancels out the residual astigmatism. In these cases, the front surface of the GP can be made spherical, resulting in a back surface toric only lens. While this concept may be confusing, most laboratories will determine the necessity for you. TORIC GP FITTING MADE EASY Before the days of empirical ordering, diagnostic fitting was performed with standard SPE fitting sets and overrefraction calculations. Now, you can design a toric GP lens with a high degree of accuracy using only keratometry readings and manifest refraction.1 You can provide this data directly to your GP lab of choice; however, if you prefer to calculate the math yourself, the GP Lens Institute (www.gpli.info) has several guides available, including a MandellMoore worksheet. Additionally, there is a GP toric calculator, which provides suggested lens parameters and indicates whether the lens is an SPE or CPE design. These resources can help improve your toric fitting confidence. RCCL 1. Michaud L, Barriault C, Dionne A, Karwatsky P. Empirical fitting of soft or rigid gas-permeable contact lenses for the correction of moderate to severe refractive astigmatism: A comparative study. Optometry. 2009 Jul;80:375-83. 2. Sarver MD. A study of residual astigmatism. Am J Optom. 1969;46(8):578-82. 3. Bennett ES, Layfield KA, Lam D, Henry VA. Correction of astigmatism. In: Bennett ES, Henry VA, eds. Clinical Manual of Contact Lenses. 4th Ed. Philadelphia: Lippincott, Williams & Wilkins; 2014:344-94. The GPLI Toric Calculator The GPLI Toric Calculator, available at www.gpli.info/lens-calculator, can help you select the correct lens parameters and either an SPE or CPE design. Example 1: SPE Spectacle Rx: -1.00-3.25x180 Ks: 42.00/45.00 BC: 42.00/44.25 BVP: -1.00/-3.25 ΔBC (2.25 D) = ΔBVP (2.25 D) Example 2: CPE Spectacle Rx: +1.00-4.50x180 Ks: 42.00/45.50 BC: 42.00/44.75 BVP: +1.00/-2.50 ΔBC (2.75 D) ≠ ΔBVP (3.50 D) Example 3: BST Spectacle Rx: plano-4.50x180 Ks: 41.00/44.00 BC: 41.00/43.25 BVP: 0.00/-3.50 ΔBC (2.25 D) x 1.5 ≈ Δ BVP (3.50 D) REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 9 Taking Torics to the T P Fitting toric lenses has become increasingly straightforward and now presents a viable option for myriad contact lens wearers. U ntil recently, toric lenses made up a fraction of contact lens prescriptions. Over the last couple of years, however, toric lens use has grown substantially—now making up 13% of our total lens fits.1 For most eye care practitioners, toric contact lens patients often seem more demanding than spherical patients due to the extra time and effort that goes into fitting them. Fortunately, new lens types and modalities are simplifying the process and making these patients happier than ever, without much added chair time. Twenty years ago, nearly every toric lens had to be custom ordered, and patients had to wait in our reception area for 20 minutes while the lens settled. Today, toric fitting sets allow for instant dispensing, and the lenses settle within minutes. With much advancement in this area, we have far fewer hurdles and can offer a higher standard of care to our patients. We live in a culture marked by instant gratification, which often presents difficulties when dealing with issues that can’t be immediately remedied. Fortunately, performing contact lens fittings from trial sets allows us to deliver care in mere minutes for the majority of our patients. In our practice, we still have patients with low degrees of astigmatism explain that past practitioners would not fit them with lenses because of their astigmatism. This is no longer the case, and it is our responsibility to show our patients the increasingly wide range of options they have—whether they’re astigmatic or not. Our toolboxes and lens options are ever increasing and— luckily for the less patient among us—the majority of these lenses take only minutes to fit. TORICITY PATTERNS We are all familiar with astigmatism, but even within each subtype certain measures require a better understanding, as they impact how a patient sees out of their lenses. For example, it is important to distinguish the differences between limbus-to-limbus and central corneal astigmatism. Topography is essential to understanding these distinctions, as research shows significant changes occur in the shape of the cornea in the periphery, thus making conical sections (like with manual keratometry or autorefractor Ks) inadequate to predict the extent of corneal astigmatism.2 If a patient has a small pupil and central astigmatism during the refraction but a large pupil in her normal environment, her true amount of revealed astigmatism may vary. This aspect of astigmatism management is also important for correctly fitting patients with gas permeable (GP) lenses. Patients with central corneal astigmatism, even with high power (>2.00D), 10 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 may do very well with a spherical lens because the lens fits in the peripheral cornea in a more spherical nature. When patients have limbus-to-limbus astigmatism, on the other hand, they may reveal only -2.00D in the refraction but need a toric GP lens at the landing point of the lens (Figures 1a and b). Other notable corneal shape features worth considering are those that are neither regular nor irregular in pattern. These patients may present with variable refractive axis with a minimally variable end point during the refraction. On topography, astigmatism in such patients may appear more like a distorted bow tie rather than a classic bow tie with-the-rule (WTR) or againstthe-rule (ATR). These toric patients may benefit from a custom lens that can mask or vault the corneal shape. Astigmatism in patients with a history of injury, surgery or ABOUT THE AUTHORS Dr. Young is an associate at Specialty Eyecare Group in Seattle, WA. She specializes in dry eye and contact lenses. She graduated with honors from Pacific University and received the AOF award of Excellence in Contact Lens Patient Care. Dr. Kading owns Specialty Eyecare Group, a Seattlebased practice with multiple locations. He specializes in anterior segment disease and custom contact lens fitting. By David Kading, OD, and Charissa Young, OD disease can vary widely—ranging from normal to irregular. Rather than suggesting they all need a custom lens, we refer back to the refraction and corneal shape (see “Case Report: Custom vs. Convenience,” p. 12). Although some patients may present with alarming findings on topography, they may have a relatively clean refraction and minimal aberrations. These patients may be suited for a standard soft lens (sphere or toric) rather than a custom lens, which might offer only a slight improvement over the standard lens. Of course, if a patient has a corneal alteration that would deem standard soft lenses impossible, custom lenses (GP sphere, GP toric, scleral or custom soft) must be employed. FITTING PROTOCOL Every lens manufacturer has its own contact lens fitting guides, which tend to be accurate and worthwhile. Still, every practice should have a fitting protocol in place to maximize their success with any toric lens design:2 1. For patients under 40, we always round up the sphere. Most trial toric lenses on the market only come in -0.50D. For example, we round the spherical power up to -1.50D in a patient with a prescription of -1.25-1.00x175. 2. When working with a patient with cylinder power that is between the options, we round down. Because soft contact lenses rotate about six degrees on average, rounding down minimizes visual distortions.3 As an example, we round the cylinder power down to -0.75D for a patient with a prescription of -1.25-1.00x175. Generally, if the sphere power is between stock powers and the cylinder power is between lens options, our practice is to round up with the sphere and down with the cylinder so that the spherical equivalent equals itself out. 3. For an axis that does not nail itself directly or clearly towards one, we round towards 180 for WTR and 90 for ATR. For a patient with a prescription of -1.25-1.00x175, we round the axis to 180 (Figure 2). For patients with presbyopia, we may elect to round down for the spherical component, but maintain the other two protocols. Figs 1a. and 1b. Topography is essential for understanding distinctions in corneal shape that affect GP lens fitting. Patients with apical astigmatism (left) often do well with spherical lenses, while those with limbal astigmatism (right) often need a toric GP lens. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 11 TAKING TORICS TO THE TOP 1. Morgan, P et al. International contact lens prescribing in 2015. Contact Lens Spectrum, January 2016. 2. Read S, Collins MJ, Carney LG, Franklin RJ. The topography of the central and peripheral cornea. Invest Ophthalmol Vis Sci. 2006 April;47:1404-15. 3. Momeni-Moghaddam H, Naroo SA, Askarizadeh F, Tahmasebi F. Comparison of fitting stability of the different soft toric contact lenses. Cont Lens Anterior Eye. 2014 Oct;37(5):346-50. CASE REPORT: CUSTOM VS. CONVENIENCE Fig 2. Off WTR astigmatism: If this axis was 15, round closer to the 180, which would be axis 10. This gives us a final lens power for our patient of -1.50-0.75x180. MAINTENANCE AND PRESCRIPTION GUIDELINES Lens comfort is paramount for success in fitting toric lenses. Addressing and treating dry eye will decrease chances of eye rubbing, which can induce lens rotation and decrease vision quality. Unless the patient has a parameter that is not available in a daily disposable modality, we recommend dailies to provide the most comfortable contact lens wearing experience. Toric single-use lenses are available from every major contact lens manufacturer. There now exist single-use silicone hydrogel lenses as well, which maintain the high oxygen permeability found in two-week or monthly lenses. Although fitting most patients with toric powers is simpler and more direct than ever before, practitioners should always apply a greater degree of scrutiny for patients who have kerato- conus or surgically altered eyes. These irregularities can account for significantly different needs and outcomes, typically requiring customized lenses to maintain corneal health and maximize visual outcomes. Most commonly, however, we find toric lenses provide much of what an average patient seeks. As a result of advancements in toric lenses over the last few years, we recommend and fit for toric single-use lenses far more often than ever before. Growth in our practice may be partially attributable to patients who elect to be part time wearers—individuals who may have never considered wearing lenses in the past. We find that with the now possible simplified approach, our patients are pleased that we have taken the time for their torics, maximizing their comfort and vision—while also preventing contact lens dropouts in our practice. 12 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 RCCL A 27-year-old presented to the office wearing a standard toric soft lens in one eye and a custom-made keratoconus lens on the other. With his toric soft lens he was 20/25 OD and with his custom lens 20/30 OS. With overrefraction he was able to achieve 20/20 with his standard soft lens but 20/20-3 with the custom lens. The latter was a quarterly replacement lens and he reported ideal comfort, but felt it a nuisance to remember two replacement systems. The patient is active in snowboarding and surfing. Standard refraction revealed -1.75 cylinder in his left eye with best corrected vision of 20/25-2. Because his topography was not regular, we understood why his prior provider had placed him in a custom lens. We elected to trial fit him into standard single-use lenses with toric parameters to see how much improvement we could achieve with a slightly stiffer modulus daily lens. We were able to achieve 20/25+2 vision. After discussion with the patient about the slight improvement and possible decreased aberrations he might have with the custom lens vs. the daily disposable lens, the patient elected to go with the daily disposable due to convenience and simplicity. Up to 16-20 CE 2017 Credits* REVIEW OF OPTOMETRY EDUCATIONAL MEETINGS OF CLINICAL EXCELLENCE 2017 MEETINGS Aspen, CO Charleston, SC February 17-21, 2017 March 24-26, 2017 Winter Ophthalmic Conference (Formerly SkiVision) Program Chair: Paul Karpecki, OD Hands-o n Worksho † ps Program Chairs: Murray Fingeret, OD & Leo P. Semes, OD San Diego, CA Orlando, FL Philadelphia, PA April 20-23, 2017 June 8-11, 2017 November 3-5, 2017 Program Chair: Paul Karpecki, OD Program Chair: Paul Karpecki, OD Joint Meeting: NT&T/OCCRS Program Chair: Paul Karpecki, OD CHECK OUR WEBSITE FOR THE LATEST INFORMATION Online: www.reviewofoptometry.com/events E-mail: [email protected] Call: 866-658-1772 OPTOMETRIC CORNEA, CATARACT AND REFRACTIVE SOCIETY 14th Annual Education Symposium Joint Meeting with NT&T In Eye Care San Diego, CA, April 20-23, 2017 Workshops not available for “Aspen, CO” meeting. See Review website for any meeting schedule changes or updates. Stock Images: ©iStock.com/JobsonHealthcare † 2017_Meetings_HouseAd-R8.indd 1 Administered by Review of Optometry ® *Approval pending 10/5/16 10:50 AM When to Opt for Scleral Lenses Irregular cornea patients in particular can enjoy the many benefits that accompany fitting scleral lenses. By Michael J. Lipson, OD S oft contact lenses come with myriad benefits and have served our patients well for over four decades. With a wide range of new designs and materials, expanded prescription ranges and customization options, we can achieve great comfort and vision in many more patients than in the past. Toric soft lenses have improved greatly in recent years, expanding the pool of soft contact lens wearers. But where do you turn for astigmatic patients who have not been successful with any soft lens options you have tried? Scleral lenses may provide the solution for practitioners who feel they’ve run the gamut with soft lens options. CANDIDATES FOR SCLERAL LENSES Ideal candidates include any patient with an irregular corneal surface. This includes patients with keratoconus, pellucid marginal degeneration, post-penetrating keratoplasty (post-PKP), corneal scarring, irregularities following refractive surgery and ocular surface disorders. My experience has shown that patients with these conditions are most appreciative of the benefits that accompany scleral lenses. For some patients, fitting sclerals may eliminate or delay the need for corneal transplant surgery.1,2 In addition, patients with ocular surface disease report less dryness when wearing scleral lenses.3,4 In cases of ocular surface disease or persistent epithelial defects, scleral lens wear can facilitate healing and long-term corneal health, as they help maintain a smooth, wet and protected corneal surface. Finally, sclerals are a great option for patients with otherwise healthy corneas who have very high prescriptions (high myopia, high hyperopia and high astigmatism). The gas permeable (GP) optics of scleral lenses provide excellent vision because they center well, have minimal movement and are not dependent on rotational orientation to correct astigmatism. BENEFITS FOR ASTIGMATS More often than not, my patients with irregular corneas love scleral lenses. Irregular cornea patients who have switched from corneal GP lenses to sclerals report improved comfort, longer wearing time and better visual acuity.5 Here are five benefits scleral lenses can provide to your irregular cornea patients: Visual acuity. Scleral lenses provide excellent visual acuity due to the inherent stability and customization possible with GP lens optics.6 Rigid materials create a new front surface for the eye by positioning the tear lens between the scleral lens and the cornea, which corrects astigmatism and irregularities of the corneal surface. One study found keratoconus 14 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 patients who were fit with scleral lenses had better acuity than when previously measured with corneal GP lenses.7 In patients who have residual astigmatism, scleral lenses can be customized with front toric optics. This astigmatic correction is placed on the front surface of the lens and requires a rotationally stable lens attained via double thin zones or toric peripheral curves. Scleral lenses can also incorporate multifocal designs to provide both distance and near vision for presbyopes. The lenses center well and can be made rotationally stable as described above. Comfort. With proper fitting, scleral lenses prove to be extremely comfortable. Most people describe the feeling of a properly fit scleral lens as being more comfortable ABOUT THE AUTHOR Dr. Lipson is an assistant professor at University of Michigan’s Kellogg Eye Center, Department of Ophthalmology and Visual Science, at the Northville location. His clinical practice involves contact lenses with an emphasis on specialty lenses for overnight corneal reshaping, keratoconus, post-corneal transplant, post-refractive surgery and severe dry eye. He conducts clinical research as the principal investigator for studies on corneal reshaping, vision-related quality of life, myopia control and new lens designs. He lectures nationally and internationally on specialty contact lens and research topics. He is a consultant for Bausch + Lomb’s Specialty Vision Product (SVP) division, specializing in education and training on specialty contact lenses with emphasis on orthokeratology. Dr. Lipson is the vice president of the Scleral Lens Education Society and a fellow of the American Academy of Optometry. This well-centered scleral lens shows no edge impingement or scleral compression. Note the continuity of blood vessels under the lens. Photo: Christine Sindt, OD than soft lenses.8 Not only are they often more comfortable, in patients with irregular corneal curvature, scleral lenses also allow patients to wear lenses for longer periods each day compared with soft lenses.9 As practitioners are well aware, lens comfort is a major factor contributing to improvement in our patients’ vision-related quality of life (QOL).8 Studies show higher QOL scores for patients wearing sclerals compared with their previous mode of correction.8,10 In one study of patients who had ocular surface disease, 45 of 49 (92%) reported improved quality of life due to the reduction of photophobia and discomfort.11 During the fitting process, if patients have adverse effects such as lens awareness or discomfort, various changes in lens parameters such as diameter, edge lift, limbal clearance, toric peripheral curves and overall sagittal depth can be modified to make scleral lenses more comfortable. These design changes improve lens comfort by minimizing edge standoff and ensuring the lens has no corneal or limbal bearing. Because of this adaptability, scleral lenses present a good alternative for a wide range of patients. Performance. Due to their size, scleral lenses do not dislodge with quick eye movements. In addition, airborne particles and dust rarely get under the lens. My clinic sees significantly fewer patients report- A decentered corneal GP lens secondary to corneal irregularity. Such a patient may experience a better fit with a scleral lens. Fitting scleral lenses isn’t a hightech endeavor; all you need is a diagnostic lens fitting set, slit lamp and phoropter. ing foreign objects beneath their scleral lenses compared with soft lens options. Further, I’ve yet to see a case of lenses dislodging. Both of these factors make sclerals a good option for patients who play sports or lead active lifestyles. Corneal health. Scleral lenses help maintain a healthy ocular surface.11 Because properly fit sclerals vault the cornea, they maintain a layer of tears that continually bathes the cornea in moisture. In patients suffering from severe dry eye or any ocular surface disorder, scleral lenses provide an ongoing therapeutic effect by keeping the corneal surface protected from trauma, irritation, dehydration and desiccation.12 Delayed surgical intervention. The use of scleral lenses may delay or eliminate the need for corneal transplant surgery.1 If a patient has been unsuccessful with previous modes of contact lens correction, scleral lenses often provide a comfortable, less costly and more convenient solution than surgery, which comes with numerous follow-up visits, long-term eye drop use and a long recovery period. ical observations are necessary to establish proper fit of a scleral lens: First is central clearance. During diagnostic fitting and evaluation, clinicians must evaluate the thickness of the tear film with an optic section to ensure full corneal clearance, record for future use or give very specific information to a fitting consultant as needed. Second is evaluation of limbal clearance. Long-term bearing on the limbus will create irritation and redness. Third is evaluation of the landing profile. The goal is to achieve a uniform, gentle landing 360°. Excessive bearing will show impingement of conjunctival vessels and increasing redness over time, while excessive lift will create increased lens awareness. Numerous resources can help you learn the necessary skills to gain confidence in fitting scleral lenses. The Scleral Lens Education Society (www.sclerallens.org) and the GP Lens Institute (www.gpli. info) are both excellent resources. Additionally, wet labs and fitting workshops at national and regional specialty contact lens meetings are a great opportunity to learn general scleral skills in a hands-on setting. It is also worth noting that scleral manufacturers hold dedicated webinars and workshops to help clinicians gain experience with a specific design. LEARNING TO FIT SCLERALS Most eye care practitioners already have the skills required to fit scleral lenses. But, at the slit lamp, scleral lens fitters need specific training to know what to look for. Three crit- REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 15 WHEN TO OPT FOR SCLERAL LENSES NOT FOR EVERY PATIENT While part of the appeal of scleral lenses is the wide range of patients for whom they prove successful, there are some exceptions. A few patient characteristics may be contraindications for scleral lenses: • If, for example, you have a patient with a very small palpebral fissure with deep-set orbit, sclerals may not be the best option. These anatomical factors can make application of the lens difficult for patients. • Most patients, even those with small eyes, can be taught to competently apply and remove scleral lenses. We do, however, occasionally come across a patient who just can’t do it and finds repeated attempts too frustrating to tolerate. • Patients with low endothe- lial cell counts (<800 cells/mm2) represent another contraindication for scleral lenses. This can occur with various corneal conditions but must be carefully evaluated in post-PKP patients. Patients with low endothelial cell counts who wear scleral lenses are more prone to significant corneal edema and the potential for graft rejection reactions.13 Although not a contraindication, the presence of pre-existing central corneal scarring will limit the vision-correcting potential of any contact lens—including sclerals. But appearances of scarring can be deceiving, and clinicians should still provide a diagnostic fitting for these patients; scleral lenses may still provide the best potential visual acuity. COMPLICATIONS As with any contact lens fitting, complications can occur with scleral lenses.13 Some include corneal neovascularization, limbal injection, corneal/conjunctival infection, corneal staining and corneal edema. To minimize complications, clinicians should provide a thorough initial fitting evaluation, patient education on proper disinfection and handling techniques, and careful follow-up procedures. In addition, the use of highly permeable materials and special solutions during application can minimize the chance of patients experiencing these complications. These instances, however, are rare and will occur less frequently with increased practitioner experience and confidence. CASE 1 A 56-year-old male was referred to me complaining of poor vision in the right eye, although his left eye is fine. He had a history of radial keratotomy in both eyes in 1992 and LASIK in the right eye in 2003. He stated he needed better vision for all activities, but especially for golf. He inquired about additional surgery, glasses or contact lenses. Other practitioners had tried a variety of CL fitting modalities over the past six years. The latest correction was a hybrid lens that provided good vision, but his comfort was not acceptable. FINDINGS • Unaided VA: OD 20/70-, OS 20/30+ • Refraction: -1.25 -4.75 x 140 20/50 OD; +0.50 -1.25 x 080 20/25 OS • Slit lamp: Eight radial RK incisional scars and two “T-cuts” superior and inferior, as well as trace LASIK flap interface visible, superiorly-hinged OD; eight RK incisional scars OS. • Topography: Irregular astigmatism with inferiornasal steepening OD. • Corneal diameter: 11.8mm evaluation went well as far as comfort and vision correction. I used an oblate back surface design to more closely parallel the post-refractive corneal topography. Corneal topography of the right eye. First lens ordered: • BC: 9.24 oblate design • OAD: 16.0 • Power: -7.00 • Sagittal depth:4.40mm At one-week follow-up he reported comfortable wearing time of eight hours, but he continued to wear them for a total of about 10 hours a day. He reported his visual acuity as quite good, and he read 20/25 with no distortions. Slit lamp evaluation showed moderate temporal hyperemia, 200 microns of central clearance and slight temporal conjunctival prolapse. I ordered a new lens with a toric landing zone (90 microns flatter in the horizontal meridian with no change vertically). With the new lens, one month SOLUTION After discussing and dismissing the potential of later, he reported excellent vision (20/25+), comfortsurgical correction and glasses, I educated him on able wearing time of 12 hours a day and only slight scleral lenses and how different they were than the and occasional redness. He also reported much betprevious contact lenses he had tried. Diagnostic ter vision on the golf course! 16 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 F itting your patients with irregular corneas with scleral lenses can be gratifying and is a worthwhile skill set to incorporate into your practice. Scleral lenses can provide comfortable lens wear, clear vision and longer wear time.9 As a practitioner, it is rewarding to hear patients who were unsuccessful in other contact lens modalities report clear vision and an improved quality of life with properly fit scleral lenses. Further, as sclerals are specialty lenses, they can generate greater revenue per patient for your practice from higher fitting fees and enthusiastic word-ofmouth referrals for other specialty patients. RCCL 1. Deloss KS, Fatteh NH, And Hood CT. Prosthetic replacement of the ocular surface ecosystem (PROSE) scleral device compared to keratoplasty for the treatment of corneal ectasia. Am J Ophthal. 2014;158:974-82. 2. Severinsky B, Behrman S, Frucht-Pery J, Solomon A. Scleral contact lenses for visual rehabilitation after penetratingkeratoplasty: Long term outcomes. Cont Lens Ant Eye. 2014;37:196-202. 3. Schornack MM, Baratz KH, Patel SV, Maguire LJ. Jupiter scleral lenses in the management of chronic graft versus host disease. Eye Cont Lens. 2008;34(6):302-5. 4. Rosenthal P, Cotter J. The Boston scleral lens in the management of severe ocular surface disease. Ophthalmol Clin N Am. 2003;16:89-93. 5. Segal O, Barkana Y, Hourovitz D, et al. Scleral lenses may help where other modalities fail. Cornea. 2003;22:308-10. 6. Stason WB, Razavi M, Jacobs DS, et al. Clinical benefits of the boston ocular surface prosthesis. Am J Ophthalmol 2010;149:54–61. 7. Schornack MM, Patel SV. Scleral lenses in the management of keratoconus. Eye Contact Lens 2010;36:39-44. 8. Bergmanson JP, Walker MK and Johnson LA. Assessing scleral contact lens satisfaction in a keratoconus population. Optom Vis Sci 2016;93. Epub ahead of print. 9. Ortenberg I, Behrman S, Geraisy W and Barequet I. Wearing time as a measure of success of scleral lenses for patients with irregular astigmatism. Eye Contact Lens. 2013;39:381-4. 10. Visser E-S, Visser R, van Lier H, Otten H. Modern scleral lenses part II: patient satisfaction. Eye Contact Lens. 2007;33:21-5. 11. Romero-Rangel T, Stavrou P, Cotter J, et al. Gas permeable scleral contact lens therapy in ocular surface disease. Am J Ophthal. 2000;130:2532. 12. Van der Worp E, Bornman D, Ferreira DL, et al. Modern scleral lenses: a review. Cont Lens Ant Eye. 2014;37:240-50. 13. Walker MK, Bergmanson JP, Miller WL, et al. Complications and fitting challenges associated with scleral contact lenses: A Review. Cont Lens and Ant Eye. 2015;39:88-96. CASE 2 A 29-year-old male was referred to me with a history of keratoconus in both eyes. When he was first diagnosed at 19, he was prescribed corneal GP lenses. He wore those for about five years with varying degrees of comfort. After hearing about new contact lens options for keratoconus, he pursued other modalities over the next five years, including: piggyback, Corneal topography of hybrid and special soft lenses. the left eye. He came in wearing the special soft lenses that provided good comfort, but he complained that vision was not acceptable and that he had to replace them every two months due to deposits. FINDINGS • Current corrected VA: 20/30- OD, 20/40 OS. • Refraction: -4.25 -4.75 x80 20/70 OD, -5.50 -5.25 x 115 20/80 OS. • Slit lamp: Apical thinning and 1-2+ vertical striae OD; apical thinning, 2+ vertical striae and trace hazy scar OS. • Topography: Irregular astigmatism with inferior temporal steepening and inferior temporal apex OU. • Corneal diameter: 12.0mm SOLUTION After discussing his history and various contact lens options, I recommended we proceed with scleral lenses. Diagnostic evaluation for fitting his left eye went well. He was happy with both the vision and comfort with the scleral lenses. I used a prolate back surface design in a 17.0mm lens. Initial diagnostic lens for the left eye: • Sagittal depth: - 4900 microns • Base curve: -7.8 • Diameter: 17.0 • Power: -2.00 • Over-refraction: 3.50 sph 20/20- Initial diagnostic lens showed small central bearing. The initial diagnostic lens showed slight central bearing but good limbal clearance and good edge alignment. The first lens I ordered had 150 microns greater sagittal depth than the diagnostic lens. First lens ordered for the left eye: • Sagittal depth: 5050 microns • BC; 7.80 prolate design • OAD: 17.0 • Power: -5.50 At one-week follow-up he reported comfortable wearing time of 14 hours and reported not needing to use any lubricating drops. He reported his visual acuity in his left eye as very good, and he read 20/20- with no distortions. Slit lamp evaluation showed minimal hyperemia that did not change with increased wearing time. The patient’s left eye after wearing the prescribed scleral lens for six hours. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 17 1 CE Credit (COPE Approval Pending) SURGICAL OPTIONS for the Correction of ASTIGMATISM Today’s sophisticated surgical tools and techniques offer dramatically improved outcomes over the imprecise early efforts of yesterday. By Kristen Brown, OD E ye care practitioners are familiar with corneal astigmatism, as this common refractive condition caused by unequal curvature along the two principal meridians greets us in the exam chair every day. Classified by axis, astigmatism is either with-therule (WTR), against-the-rule (ATR) or oblique; it can be further categorized as regular or irregular. These terms and their clinical manifestations are a part of routine practice; however, the advent of wavefront analysis in recent years has enhanced our understanding of irregular astigmatism with the classification of higher-order aberrations such as coma, trefoil and quadrafoil.1 The portfolio of options for the surgical correction of astigmatism has expanded significantly over the past two decades. Photorefractive procedures such as laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) are well established. The introduction of femtosecond-laser (FS) technology has opened the door for new surgical strategies including laser-assisted cataract surgery and the recently FDA approved small-incision lenticule extraction (SMILE) procedure. Meanwhile, incisional options such as astigmatic keratotomy (AK) continue to evolve as FS technology adds a level of precision not seen with manual techniques. FS lasers can be combined with toric intraocular lenses (IOLs) to address the growing demand for refractive cataract surgery. Surgical correction of astigmatism has a promising future. Improved strategies are evolving in the areas of topography-guided laser procedures, ray tracing, patterned corneal collagen crosslinking and toric multifocal intraocular lenses.2,3 THE RISING TIDE Astigmatism accounts for about 13% of all refractive error.4 As much as 90% of the world’s population has some degree of astigmatism, including 20% with 1.5D or more cylinder.5 Approximately 63% of individuals under 40 have 0.25D or more astigmatism, while most have less than 1D.6-8 Research reveals that myopia and astigmatism are increasing at an alarming rate, both surfacing at a younger age and growing in prevalence throughout the early and adolescent years.9,10 In the United States, myopia prevalence is nearly twice what it was 30 years ago.11-13 In 2015, investigators found that 50% of urban populations in East Asia were myopic, with 90% of university students displaying myopia or 18 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 myopic astigmatism.10 Research estimates that myopia—and presumably myopic astigmatism—will affect nearly six billion people by the year 2050.13 This astonishing rise has ramifications for eye care professionals around the world involved in the prevention, management and surgical correction of myopia and astigmatism. FROM AK TO SMILE: A RETROSPECTIVE ON SURGICAL METHODOLOGY Astigmatic keratotomy was one of the first forms of refractive surgery developed to correct astigmatism. AK became available in the United States shortly after radial keratotomy (RK) was introduced in 1978.14 During AK, peripheral arcuate incisions are made with a diamond blade knife along the steep axis of corneal astigmatism to flatten that axis.15 Though RK has fallen out of favor due to diurnal fluctuation in acuity and unpredictable longterm results, AK is still a conveABOUT THE AUTHOR Dr. Brown is clinical director of TLC Laser Eye Centers of Boston, MA, and Providence, RI. She is a member of the TLC Clinical Director Advisory Group and holds a faculty appointment at the New England College of Optometry. She is involved in clinical research, teaching and lecturing. Release Date: November 2016 Expiration Date: November 1, 2019 Goal Statement: Surgical correction of astigmatism has a promising future. This article discusses the improved strategies that are evolving in the areas of topographyguided laser procedures, ray tracing, patterned corneal collagen crosslinking and toric intraocular lenses. Faculty/Editorial Board: Kristen Brown, OD Credit Statement: COPE approval for 1 hour Preoperative topography of a patient’s left eye prior to having undergone a combined one-site cataract and trabeculectomy surgery with LRI. Regular 5.5D of with-therule astigmatism can be seen with an axis of 80°. Photo: Allister Gibbons, MD bances (ghosting, glare or halo) and residual refractive error are rare and most resolve after the first year.28 Customized ablation profiles materialized about a decade ago when aberrometers became available to measure the wavefront of the eye. Wavefront data is obtained by projecting a flat plane or “wave” of light into the eye and measuring the location of the corresponding light spots reflected from the retina. The relative location of reflected light is then used to calculate the power of the optical system where each spot of light enters the eye. The goal of custom or wavefront-guided (WFG) laser ablation is to reduce the imperfections or higher-order aberrations (HOAs) of the optical system.29 Original “conventional” laser ablation profiles with the very first excimer lasers did not aim to correct HOAs and tended to create an oblate (centrally flat) corneal profile. They were also more likely to induce postoperative HOAs like spherical aberration. Wavefrontoptimized (WFO) ablations were also designed to customize laser ablations but do not rely on wavefront measurement of the eye. WFO treatments are based on refraction data, keratometry and a peripheral ablation profile specific to each cornea. This peripheral algorithm results in a more prolate corneal shape Photo: Allister Gibbons, MD nient, relatively inexpensive procedure. Compared with LASIK or PRK, however, astigmatic keratotomy is less predictable and has a lower range of astigmatic effect.16-19 The application of FS lasers has given surgeons better control of the length, depth and location of AK incisions, leading to finer precision, less risk and better visual outcomes.20-23 A big advantage of FS AK is that cuts can be penetrating or intrastromal without a break in the epithelium. This allows for titration of the effect and better patient comfort.24 Low to moderate astigmatism (1D to 3D) can also be corrected with intracorneal ring segments (ICRS). The goal of ICRS implantation is typically to delay or prevent corneal graft surgery; it is most often employed in ectatic conditions such as keratoconus, post-LASIK ectasia and pellucid marginal degeneration.25 As with AK, ICRS can be done manually or with an FS laser to create tunnels that are more precise, more predictable and associated with fewer complications and similar visual outcomes.26 Photoablation with an excimer laser (i.e., LASIK and PRK) has become the prevailing surgical option for patients who desire an alternative to eyeglasses and contact lenses. The FDA first approved the excimer for spherical myopia in 1995, but the option to treat astigmatism and hyperopia didn’t become available until several years later. A 2004 study found that one to two million people in the United States undergo LASIK or PRK.27 US Military personnel opt for refractive laser surgery at twice the rate of the general population.28 Adverse events such as dry eye symptoms, night vision distur- The same patient three months after combined one-site cataract and trabeculectomy surgery with LRI. In retroillumination, we can verify the rotational stability of the lens at 80°. following laser ablation and is thought to induce fewer postoperative HOAs.30 Custom ablations are indicated for myopia as high as -12D with astigmatism up to -3.75D on of continuing education credit is pending for this course. Check with your state licensing board to see if this counts toward your CE requirements for relicensure. Joint-Sponsorship Statement: This continuing education course is jointsponsored by the Pennsylvania College of Optometry. Disclosure Statement: The author has no financial interest in any products mentioned in this article. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 19 SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM most wavefront-guided excimer laser platforms. Similarly, wavefront-optimized ablation profiles can correct up to -12D myopia and provide an expanded range of astigmatism correction—up to -6D, for example—with the Wavelight EX500 excimer laser (Alcon). Wavefront-guided visual outcomes have been excellent compared with conventional ablation profiles; however, they are dependent of aberrometry measurements which are affected by pupil size, pupil centration and accommodation.31 In addition, corneal, lens and vitreous opacities limit the ability to capture good wavefront data. As lenticular aberrations change over time, correcting the wavefront of the whole eye may not be an optimal strategy for treating irregular astigmatism and other HOAs. TOPOGRAPHY-GUIDED LASER ABLATION Refractive surgeons in the United States can now perform topography-guided laser ablation, which been growing in popularity outside the United States for many years.32 The FDA granted approval for topography-guided treatment on normal (i.e., previously untreated) eyes on the Nidek laser in October of 2013 and the Alcon laser system in 2015. Topography-guided ablation normalizes or smooths the corneal surface by correcting only the HOAs that arise from the cornea, leaving internal aberrations unchanged. Topography-guided technology integrates placido disc topography, keratometry and pupillometry in a single diagnostic device that integrates with planning software and excimer laser technology.32 Unlike with WFG ablations, informa- tion about sphere and regular astigmatism (the lower-order aberrations) is not captured by topography and must be obtained separately, by refraction, for example. Recent research evaluating the safety and effectiveness of topography-guided LASIK found that visual symptoms such as glare, halo and starbursts were reduced—and, more surprisingly, 30.9% of subjects gained one or more lines of uncorrected visual acuity compared with preoperative best corrected visual acuity.32 Outside the United States, topography-guided procedures can be conducted on highly aberrated eyes such as those with small or decentered optical zones from previous corneal refractive surgery, eyes with naturally occurring irregular corneal astigmatism or irregular astigmatism from trauma.33,34 With age, the axis of astigmatism shifts toward an ATR orientation primarily due to changes in the cornea, not the lens. A reduction in eyelid tension over time may partly explain this shift, as internal astigmatism remains relatively stable with age.35 Despite minimally invasive approaches, modern cataract surgery can induce corneal astigmatism even with the small incisions made in the peripheral cornea. Like AK, incisions made for cataract surgery entry wounds cause flattening in the meridian incised and steepening in the meridian 90 degrees away.36 Superior incisions cause flattening of the vertical meridian or an increase in ATR astigmatism, while temporal incisions lead to flattening in the horizontal meridian or an increase in WTR astigmatism. The amount varies with individual differences in corneal biomechan- 20 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 ical properties, surgical technique and type of surgery performed.37 Understanding and managing surgically induced corneal astigmatism (SICA) is necessary for surgeons to succeed in an era of patients opting for refractive cataract surgery, which includes post-op uncorrected emmetropia as a goal. Many have had previous LASIK or PRK and expect to return to post-laser, spectacle-free status. LRIs AND IOLs During cataract surgery, corneal astigmatism can be corrected with limbal relaxing incisions (LRIs), toric IOLs or a combination of the two. In addition, a femtosecond laser can be employed to assist the surgeon with steps that are typically performed manually. Laser-assisted cataract surgery (LACS) adds a level of precision to the procedure, which may improve visual outcomes and lessen the risk of postoperative complications such as endothelial cell loss and macular edema.38 LRIs are positioned more peripherally in the cornea than AK incisions and are preferred in cataract surgery since the same incision can be used for phacoemulsification. Compared with astigmatic keratotomy, LRIs are associated with less pain and less induced irregular astigmatism.39 Further, they are quick and effective at reducing up to 1.5D of corneal astigmatism. Toric IOLs are a better option for surgical correction of moderate (1.5D to 4.25D) astigmatism. Several toric IOLs of various material and astigmatic power are available in the United States, including the Staar Toric (Staar Surgical), Acrysof IQ Toric (Alcon), Tecnis Toric (AMO) and Trulign Toric (Bausch + Lomb). For successful correction of astigmatism, toric IOLs must be aligned with the visual axis and the steep meridian of the cornea. Some lenses can rotate, which will reduce the effectiveness and leave residual astigmatism at a new, often oblique, meridian. Anterior and posterior corneal astigmatism must both be considered when planning IOL surgery—particularly in patients who want less dependence on spectacle correction. Inaccuracies arise when posterior corneal astigmatism is measured with the assumption that there is a fixed-ratio relationship with the anterior corneal curvature.40 The Cassini Corneal Shape Analyzer (i-Optics) is a new topographer that uses LED ray tracing technology with 700 diode lights to measure anterior and posterior corneal astigmatism. Advances in cylinder and axis measurement precision can be useful for preoperative planning of toric IOL implants, particularly in post-laser refractive surgery patients.41 In addition, the use of intraoperative aberrometry can guide IOL power selection. The Optiwave Refractive Analysis system (Alcon) employs wavefront interferometry to produce a fringe pattern; distortions in this pattern are then translated into refractive values.42 Research on toric IOL power selection aided by intraoperative aberrometry reveals that patients were 2.4 times more likely to have less than 0.50D of residual refractive astigmatism when an intraoperative aberrometer was used.43 Advantages of LACS over manual cataract surgery include the customization of corneal incisions, precision and the centration of the capsulotomy for improved refractive stability and predictability. Fragmenting the lens before phacoemulsification is another advantage of LACS that is believed to be less likely to induce endothelial cell loss.43 For astigmatism greater than 4.25D at the corneal plane, it may be necessary to combine LRIs with toric IOLs or subsequent LASIK or PRK for up to 10D corneal astigmatism correction. The newest frontier combines Pre-op topography (Vario, Alcon) of a highly astigmatic patient to be treated with Wavelight FS200/EX500 (Alcon) wavefront optimized system. Left image: +4.25 -4.75x175 20/25 OD. Right image: +4.50 -5.25x005 20/25 OS. Pentacam imaging of the same WFO-treated patient (right eye only). Left image: pre-op OD. Right image: one month post-op OD. At one month post-op, UCVA is 20/20 plano -0.25x005 20/20 OD. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 21 SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM astigmatism and presbyopia treatment in one IOL. The recently FDA approved Tecnis Symfony Toric IOL (AMO) and the forthcoming Acrysof IQ Restor Toric (Alcon) are two early entrants into this emerging category. NO LONGER AN AFTERTHOUGHT Although significant astigmatism is typically defined as 1D or more, amounts as low as 0.25D can impact visual acuity or visual quality in some individuals. Planning and predicting the outcome of refractive surgery is the foremost challenge a surgeon faces. With the explosion of more advanced technology and improved surgical outcomes, there is increasing expectation that refractive procedures can and will provide excellent visual results with minimal risk, and that astigmatism correction must now be part and parcel of the surgical approach. Future advances will focus on corneal biomechanical properties and wound healing response, which is one of the few remaining limitations affecting the predictability and stability of refractive surgery. RCCL 1. Kelly JE, Mihashi T, Howland HC. Compensation of corneal horizontal/vertical astigmatism, lateral coma and spherical aberration by internal optics of the eye. J Vision. 2004;4:262–71. 2. Cummings AB, Kelly GE. Optical ray tracing-guided myopic laser in situ keratomileusis:1-year clinical outcomes. Clinical Ophthalmology. 2013;7:1181–91. 3. Ibrahim Seven MS, Sinha Roy A, Dupps WJ Jr. Patterned corneal collagen crosslinking for astigmatism: Computational modeling study. J Cataract Refract Surg. 2014 June;40(6):943–53. 4. Read SA, Collins MJ, Carney LG. A review of astigmatism and its possible genesis. Clin Exp Optom. 2007;90(1):5–19. 5. Porter J, Guirao A, Cox IG, Williams DR. Monochromatic aberrations of the human eye in a large population. J Opt Soc Am A. 2001;18:1793–1803. 6. Ferrer-Blasco T, Montés-Micó R, Peixoto-de-Matos SC, et al. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg. 2009;35:70-5. 7. Saunders H. Age-dependence of human refractive errors. Ophthalmic Physiol Opt. 1981;(1):159–74. 8. Fledelius HC, Stubgaard M. Changes in refraction and corneal curvature during growth and adult life. A cross-sectional study. Acta Ophthalmol. 1986;64:487–91. 9. Gwizada J, Grice K, Held R, et al. Astigmatism and the development of myopia in children. Vision Research. 2000;40:1019–26. 10. Smith MJ, Walline JJ. Controlling myopia progression in children and adolescents. Adolesc Health Med Ther. 2015;6:133-40. 11. Read SA. Ocular and environmental factors associated with eye growth in childhood. Optom Vis Sci. 2016;93:1031–41. 12. Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology. 2008;115:1279–85. 13. Holden BA, Fricke TR, Wilson DA. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016 May;123(5):1036-42. 14. Waring GO. Refractive keratotmy for myopia and astigmatism. St Louis, MO: Mosby-Year Book; 1992. 15. Hanna KD, Jouve FE, Waring GO 3rd, Ciarlet PG. Computer simulation of arcuate keratotomy for astigmatism. Refract Corneal Surg. 1992 MarApr;8(2):152-63. 16. Waring GO 3rd, Lynn MJ, McDonnell PJ. Results of the prospective evaluation of radial keratotomy (PERK) study 10 years after surgery. Arch Ophthalmol. 1994;112(10):1298-308. 17. Kemp JR, Martinez CE, Klyce SD, et al. Diurnal fluctuations in corneal topography 10 years after radial keratotomy in the Prospective Evaluation of Radial keratotomy Study. J Cataract Refract Surg. 1999 Jul;25(7):904-10. 18. Kohnen T, Buhren J. Corneal first-surface aberration analysis of the biomechanical effects of astigmatic keratotomy and a micro-keratome cut after penetrating keratoplasty. J Cataract Refract Surg. 2005;31:185–9. 19. Montes-Mico R, Munoz G, Albarran-Diego C, et al. Corneal aberrations after astigmatic keratotomy combined with laser in situ keratomileusis. J Cataract Refract Surg. 2004;30:1418–21. 20. Abbey A, Ide T, Kymionis GD, Yoo SH. Femtosecond laser-assisted astigmatic keratotomy in naturally occurring high astigmatism. Br J Ophthalmol. 2009;93(12):1566–9. 21. Hoffart L, Proust H, Matonti F, et al. Correction of post-keratoplasty astigmatism by femtosecond laser compared with mechanized astigmatic keratotomy. Am J Ophthalmol. 2009;147(5):779–87. 22. Oshika T, Shimazaki J, Yoshitomi F, et al. Arcuate keratotomy to treat corneal astigmatism after cataract surgery: a prospective evaluation of predictability and effectiveness. Ophthalmology. 1998;105(11):2012–6. 23. Aristeidou A, Taniguchi EV, Tsatsos M, et al. The evolution of corneal and refractive surgery with the femtosecond laser. Eye and Vision. 2015 Jul 14;2:12. 24. Bahar I, Levinger E, Kaiserman I, et al. IntraLase-enabled astigmatic keratotomy for post-keratoplasty astigmatism. Am J Ophthalmol. 2008;146(6):897–904. 25. Cosckunseven E, Kymionis GD, Tsiklis NS, et al. One-year results of intrastromal corneal ring segment implantation (KeraRing) using femtosecond laser in patients with keratoconus. Am J Ophthalmol. 2008;145(5):775–9. 26. Piñero DP, Alio JL, El Kady B, et al. Refractive and aberrometric outcomes of intracorneal ring segments for keratoconus: mechanical versus femtosecond-assisted procedures. Ophthalmology. 2009;116(9):1675–87. 27. Duffey RJ, Leaming D. Trends in refractive 22 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 surgery in the United States. J Cataract Refract Surg. 2004;30(8):1781–5. 28. Blitz JB, Hunt DJ, Cost AA. Post Refractive surgery complications and eye disease, active duty US armed forces 2005-2014. MSMR. May 2016;23(5). 29. Subbaram MV, MacRae SM. Customized LASIK treatment for myopia based on preoperative manifest refraction and higher order aberrometry: the Rochester nomogram. J Refract Surg. 2007 May;23(5):435-41. 30. Randleman JB et al. Outcomes of wavefront-optimized surface ablation. Ophthalmology 2007 May;114(5):983-8. 31. Sáles CS, Manche EE. One-year outcomes from a prospective, randomized, eye-to-eye comparison of wavefront-guided and wavefront-optimized LASIK in myopes. Ophthalmology. 2013 Dec;120(12):2396-402. 32. Stulting RD, Fant BS, The T-CAT Study Group. Results of topography-guided laser in situ keratomileusis custom ablation treatment with a refractive excimer laser. Cataract Refract Surg. 2016 Jan;42(1):11-8. 33. Alio JL, Belda JI, Osman AA, Shalaby AMM. Topography-guided laser in situ keratomileusis (TOPOLINK) to correct irregular astigmatism after previous refractive surgery. J Refract Surg. 2003;19:516–27. 34. Lin DT, Holland S, Tan JC, Moloney G. Clinical results of topography-based customized ablations in highly aberrated eyes and keratoconus/ectasia with cross-linking. J Refract Surg. 2012;28(11 suppl):S841-8. 35. Anstice J. Astigmatism—Its components and their changes with age. Am J Optom Arch Am Acad Optom. 1971;48:1001–6. 36. Simsek S, Yaşar T, Demirok A, et al. Effect of superior and temporal clear corneal incisions on astigmatism after sutureless phacoemulsification. J Cataract Refract Surg. 1998;24:515–8. 37. Dupps WJ Jr, Wilson SE. Biomechanics and wound healing in the cornea. Exp Eye Res. 2006;83(4):709-20. 38. Callou TP, et al. Advances in femtosecond laser technology. Clinical Ophthalmology 2016:10 697–703. 39. Settas G, Settas C, Minos E, et al. Photorefractive keratectomy (PRK) versus laser assisted in situ keratomileusis (LASIK) for hyperopia correction. Cochrane Database Syst Rev. 2012;(6): CD007112. 40. Koch DD. The posterior cornea: hiding in plain sight. Ophthalmology. 2015;122(6):1070–1. 41. Kanellopoulos J, Asimellis G. Distribution and repeatability of corneal astigmatism measurements (magnitude and axis) evaluated with color light emitting diode reflection topography. Cornea. 2015;34(8):937–44. 42. Huelle JO, Katz T, Druchkiv V, et al. First clinical results on the feasibility, quality and reproducibility of aberrometry-based intraoperative refraction during cataract surgery. British J Ophthalmol. 2014;98(11):1484-91. 43. Hatch KM, Woodcock EC, Talamo JH. Intraocular lens power selection and positioning with and without intraoperative aberrometry. J Refract Surg. 2015;31(4):237–42. CE TEST ~ NOVEMBER 2016 1. Which of the following procedures was first used to correct astigmatism? a. Toric intraocular lenses. b. LASIK. c. Astigmatic keratotomy. d. Small-incision lenticule extraction. 2. Which procedure is associated with fluctuation in vision and unpredictable results long term? a. PRK. b. Laser-assisted cataract surgery. c. Radial keratotomy. d. Astigmatic keratotomy. 3. Which statement is true regarding custom excimer laser ablation (LASIK/ PRK)? a. Custom laser ablation treats higher-order and lower-order aberrations. b. Custom laser vision correction treats only lower-order aberrations. c. Custom laser ablation treats only higher-order aberrations. d. Custom laser ablation treats neither higher-order nor lower-order aberrations. 4. Wavefront data is obtained by which device? a. Phoropter. b. Aberrometer. c. Keratometer. d. Pupillometer. 5. Topography-guided laser ablation corrects: a. Internal aberrations. b. Lenticular opacities. c. Hyperopia. d. Aberrations of the corneal surface. 6. Normalizing the corneal surface with topography-guided laser ablation: a. Has been associated with improved uncorrected acuity over preoperative best-corrected acuity in some patients. b. Has been associated with a high risk of losing best-corrected acuity in many patients. c. Is not currently FDA approved in the United States. d. Corrects only symmetric corneal astigmatism. 7. Toric Intraocular lenses are a good option for patients with: a. A low amount of internal astigmatism. b. A moderate to high amount of corneal astigmatism. c. Macular degeneration. d. A moderate amount of lenticular toricity. 8. Which statement is true regarding limbal relaxing incisions? a. Should never be combined with toric intraocular lenses. b. Should only be performed manually. c. Can be performed with an excimer laser. d. Can be performed with a femtosecond laser. EXAMINATION ANSWER SHEET Surgical Options for the Correction of Astigmatism Valid for credit through November 1, 2019 Online: This exam can also be taken online at www.reviewofcontactlenses.com. Upon passing the exam, you can view your results immediately. You can also view your test history at any time from the website. Directions: Select one answer for each question in the exam and completely darken the appropriate circle. A minimum score of 70% is required to earn credit. Mail to: Jobson Optometric CE, Canal Street Station, PO Box 488 New York, NY 10013 Payment: Remit $20 with this exam. Make check payable to Jobson Medical Information LLC. Credit: COPE approval for 1 hour of CE credit is pending for this course. Sponsorship: Joint-sponsored by the Pennsylvania College of Optometry Processing: There is an eight-to-10 week processing time for this exam. Answers to CE exam: A B C 1. A B C 2. A B C 3. A B C 4. A B C 5. 6. 7. 8. 9. 10. D D D D D A B C D A B C D A B C D A B C D A B C D Evaluation questions (1 = Excellent, 2 = Very Good, 3 = Good, 4 = Fair, 5 = Poor) Rate the effectiveness of how well the activity: 1 2 3 4 5 11. Met the goal statement: 12. Related to your practice needs: 1 2 3 4 5 13. Will help improve patient care: 1 2 3 4 5 1 2 3 4 5 14. Avoided commercial bias/influence: 15. How do you rate the overall quality of the material? 1 2 3 4 5 16. Your knowledge of the subject increased: Greatly Somewhat Little 17. The difficulty of the course was: Complex Appropriate Basic 18. How long did it take to complete this course? _________________________ 19. Comments on this course: _________________________________________ ___________________________________________________________________ 20. Suggested topics for future CE articles: ______________________________ ___________________________________________________________________ Identifying information (please print clearly): First Name Last Name Email The following is your: Home Address Business Address Business Name 9. Which statement is false regarding femtosecond laser technology? a. The use of FS lasers in ocular surgery has expanded significantly over the past 20 years. b. The use of FS lasers in ocular surgery peaked then faded in popularity over the past 10 years. c. FS lasers are used to create corneal flaps in LASIK, corneal incisions in cataract surgery and lenticule creation in the SMILE procedure. d. FS lasers are high-energy, high-speed lasers that can be used to improve the precision of ocular surgery. 10. Which statement is accurate regarding the surgical options for correction of astigmatism? a. Surgical correction of astigmatism is not relevant during cataract surgery. b. Correction of even small amounts of astigmatism is important in refractive surgery. c. The ability to correct mild to severe astigmatism has improved significantly over the past 20 years. d. Both b and c. Address City State ZIP Telephone # - - Fax # - - By submitting this answer sheet, I certify that I have read the lesson in its entirety and completed the self-assessment exam personally based on the material presented. I have not obtained the answers to this exam by fraudulent or improper means. Signature: ________________________________________ Date: _____________ Please retain a copy for your records. LESSON 113633, RO-RCCL-1116 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 23 CASE REPORT BY BRIAN CHOU, OD Solving Scleral Contact Lens Induced Pingueculitis The simplest option is often the best solution. A B ST R AC T This case report describes the steps taken to solve scleral lens-induced pingueculitis in a keratoconus patient by refitting the patient into a smaller diameter scleral lens. A discussion ensues on other possible treatments, including lens notching, micro vaults, increasing lens diameter and hybrid lenses. Keywords: Pinguecula, pingueculitis, scleral lens, contact lenses, keratoconus INTRODUCTION Keratoconus is the prototypical, naturally-occurring condition typified by elevated lower and higher-order aberrations due to a distorted cornea.1 The primary treatment for visual rehabilitation is a rigid contact lens to re-establish a smooth refracting surface so the tear lens underneath optically neutralizes the aberrations resulting from the irregular corneal surface.2 Although a simple concept, it is frequently undermined by a host of factors, including: inability to sustain comfortable lens wear; difficulty with lens handling; poor ocular physiology, such as corneal abrasions,3-9 corneal staining and other epitheliopathy, vascularized limbal keratopathy or DuBois ring; and lens dislodgement and ejection. Scleral contact lenses have gained popularity as an effective treatment to restore vision in keratoconus and other thinning disorders, including in patients who have previously failed in traditional corneal gas permeable (GP) and hybrid contact lenses.3,4 Patients wearing scleral lenses often report excellent comfort, most likely because the lenses vault the sensitive cornea and rest on the relatively insensitive conjunctiva and underlying sclera.3,5,6 A common challenge to successful scleral lens wear is the presence of a pinguecula on the conjunctiva, which may mechanically interact with the landing area of the lens, causing redness and discomfort.7,8 In one study, nearly half of the population had a pinguecula.9 While the elective contact lens wearer can discontinue contact lens wear and use glasses, most patients with keratoconus require the functional vision that only rigid-surface contact lenses can provide. The prospect of excellent vision at the cost of eye redness and discomfort is not acceptable—nor is poor vision with a comfortable, white eye. However, keratoconus patients with pingueculitis due to scleral contact lens wear can often remain in this modality with appropriate lens modification. CASE REPORT History A 39-year-old Caucasian male presented on referral for keratoconus care after relocating from another city. He reported wearing a contact lens (SynergEyes ClearKone) only in the right eye. He indicated an inability to tolerate wearing any contact lens in his left eye, including a corneal rigid lens, piggyback system with a corneal rigid lens and various hybrid contact lenses. He did not use any eyeglasses. Family ocular history was unremarkable, he denied taking any regular medication and had no known drug allergies. He had no previous ocular surgery, and general health was unremarkable. Diagnostic Data Unaided visual acuity was 20/100 OD and 20/400 OS. Autorefraction yielded readings of -2.50 -5.25X066 OD and no obtainable measurement OS. Manifest refraction was -2.506.00X065 OD yielding 20/30, and 24 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 gave no improvement OS. Corneal topography showed asymmetric corneal steepening OU, with significant irregularity, especially OS (Figure 1). Contact lens evaluation of his SynergEyes ClearKone lenses OU ABOUT THE AUTHOR Dr. Chou is a partner at EyeLux Optometry in San Diego, CA, where he directs a referral-based keratoconus clinic. CASE REPORT was performed, including assessment of his left lens, which he did not wear due to discomfort. High molecular weight fluorescein was applied and showed an optimal fluorescein pattern OD with good centration and approximately 150 microns of central vault, and an alignment relationship over the inner landing zone (ILZ). The fluorescein pattern OS showed hard apical bearing with inferior decentration, with an alignment relationship over the ILZ and no skirt fluting. Contact lens acuity was 20/25 OD with spherocylindrical overrefraction of +0.75-0.75X140 yielding 20/20, and 20/25 OS with spherical overrefraction of -0.50 DS yielding 20/25+. Biomicroscopy revealed that lids and lashes were normal, while the conjunctiva and sclera were unremarkable with no obvious conjunctival elevations. The right cornea showed iron deposition (Fleischer’s ring) and no apical scarring. The left cornea also showed a Fleischer’s ring, grade 2+ apical scarring and vertical folds at the level of Descemet’s (Vogt’s striae). Anterior chambers were deep and quiet, and the irides were healthy with normal anatomy. Dilated examination was performed using a 78D condensing lens and biomicroscope, and using a 20D condensing lens with binocular indirect ophthalmoscopy. Crystalline lenses were clear, and anterior vitreous showed no liquefaction. Optic nerves were healthy with full neuroretinal rim tissue with C/D ratios of 0.2. Retinal vasculature, maculae and retinal peripheries were normal as well. Diagnosis I diagnosed keratoconus OS > OD with contact lens discomfort OS attributable to the pronounced corneal distortion causing me- Fig. 1. Topography showing corneal irregularity, more in the left than right eye. chanical interaction with the hybrid lens. Treatment I did not prescribe glasses because the patient rejected the manifest refraction when in a trial frame. I conveyed information about the eye disease, including how significant progression was unlikely at his age, as keratoconus is known to arrest on its own by the third to fourth decade of life.10 I recommended prescribing scleral contact lenses for both eyes and he scheduled a diagnostic fitting visit. When he returned for diagnostic lens fitting, I started with Jupiter scleral lenses (Visionary Optics). The following initial lenses were applied with fluorescein (NaFl): OD: 7.50mm base curve, -5.00D power, 18.2mm diameter, standard peripheral system. OS: 6.25mm base curve, -14.00D power, 18.2mm diameter, standard peripheral system. The NaFl pattern OD showed excessive central bearing. Overrefraction was not performed. OS showed optimal fitting characteristics with good centration and approximately 250 micron central clearance extending toward the limbus and a scleral landing zone without any noted vascular blanching or edge lift. Spherical overrefraction OS was +1.00DS yielding 20/25. A new right diagnostic lens with greater sagittal depth was applied with 7.18mm base curve, -7.00D power, 18.2mm diameter and standard peripheral system. This lens showed an optimal NaFl pattern with slight inferotemporal decentration, approximately 250 microns of central clearance and light superonasal touch in the corneal periphery. The scleral landing zone appeared ideal without vasculature blanching or edge lift. Spherical over-refraction was -0.25DS yielding 20/25+. The final scleral lenses had the following parameters: OD: 7.18mm base curve, -7.25D power, 18.2mm REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 25 CASE REPORT Dispensing and Training Visit Roughly two weeks later, I dispensed the scleral lenses and trained him on proper application, removal and lens care. Contact lens acuity was 20/25+ with a spherical overrefraction of plano DS in each eye. A cursory evaluation using biomicroscopy showed a contact lens fitting relationship consistent with what I expected from the previous visit without air bubbles OU. He was cleared to wear his new contact lenses up to full waking hours, if well tolerated, and asked to return for a contact lens progress visit in one to two weeks. left lens showed centration with approximately 250 microns of central clearance with a relatively even post-lens tear film extending toward the limbus, but mild peripheral vascular blanching at the nasal scleral landing zone. A new left lens was ordered with identical parameters except the scleral landing curve was changed from 14.50/0.5 to 15.50/0.5. When he returned to exchange his existing OS scleral lens for the new lens, visual acuity in the eye was 20/25+ with a plano overrefraction. The new lens showed an improved fitting relationship with reduced nasal peripheral vascular blanching. There was no noticeable decrease in the central clearance. The patient was asked to report back within two weeks in the event there were any bothersome symptoms, but otherwise to return for routine examination in 12 months. Progress Visits A week and a half later, he returned reporting that both new lenses performed well with excellent vision. Comfort in the right eye was excellent, and comfort in the left eye had improved by 90% compared with his previous experiences with other modalities. He noted that there was some tolerable redness and soreness in the left eye, especially by the end of the day. Wearing time at this visit was four hours. Contact lens acuity was 20/25+ with a spherical overrefraction of plano DS in each eye. Fluorescein evaluation of the right lens showed slight inferotemporal decentration but an otherwise optimal fitting relationship with approximately 250 microns of central clearance and relatively even post-lens tear film distribution, but light superonasal peripheral touch. The Annual Examination with Contact Lens Evaluation When he presented the next year for his routine examination, he reported doing overall quite well wearing scleral contact lenses. However, he noted in the past one to two months the nasal conjunctival area of his left eye was red and sore. He stated that it was mostly a cosmetic issue and that on some occasions he would only wear the right scleral lens. Personal health history was unchanged with no regular medication and no known medication allergies. Contact lens acuity was 20/25 OD with an overrefraction of -0.50D giving 20/25+, and 20/25+ OS with a plano overrefraction OS. Biomicroscopy showed no changes to the right eye from the previous examination. However, the left eye showed an area nasally diameter, standard peripheral system, Boston XO Clear with drill dot. OS: 6.25mm base curve, -13.00D power, 18.2mm diameter, standard peripheral system, Boston XO Clear. 26 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 of raised and injected conjunctival tissue, which was interacting with the scleral lens edge (Figure 2). Another Diagnosis I diagnosed pingueculitis in the left eye related to mechanical interaction with the nasal edge of the scleral contact lens. He was scheduled to return for diagnostic contact lens prescribing into a smaller diameter lens in the left eye. Treatment When he returned for diagnostic fitting into new scleral lenses, the primary goal was to prescribe a smaller diameter lens in the left eye to reduce the amount of mechanical interaction against the small nasal pinguecula. The new lens design selected for the left eye was the 16.5mm diameter ICD scleral lens (Paragon Vision Sciences), as this diagnostic set was available in the office. Concurrently, I re-prescribed the right lens from the Jupiter design into the Europa design (Visionary Optics) which, according to the manufacturer, is an improved design with a larger optic zone, reverse geometry mid-peripheral reverse curve and an enhanced haptic profile.11 First diagnostic lenses (Europa design OD, ICD design OS): OD: 7.18mm base curve, -2.50D power, 18.0mm diameter, standard peripheral system. OS: 6.88mm base curve, -5.00D power, 16.5mm diameter, standard peripheral system, 4500 sag. The right lens showed slight inferotemporal decentration with approximately 250 microns of central clearance with some light superonasal peripheral thinning of the post-lens tear film. The CASE REPORT Fig. 2. Left eye after removal of 18.2mm diameter scleral lens showing conjunctival injection, especially nasally surrounding pingueculum, and also Charleux’s sign with retroillumination. Fig. 3. Left eye showing resolution of pingueculitis after the patient was prescribed the new 16.5mm diameter scleral lens. scleral landing zone was optimal. Spherical over-refraction OD was -5.50DS yielding 20/25+. The left lens showed centration and moderate central apical bearing. Due to the lack of central clearance, the following diagnostic lens with 300 microns of additional sagittal depth was then applied: OS: 6.62mm base curve, -8.00D power, 16.5mm diameter, standard peripheral system, sag: 4800 sag. This new left lens was centered with approximately 150 microns of central clearance and a relatively even post-lens tear film extending toward the limbus, with an ideal scleral landing relationship. Spherical overrefraction OS was -2.25 yielding 20/25. The following contact lenses were ordered (Europa OD, ICD OS): OD: 7.18mm base curve, -7.75D power, 18.0mm diameter, standard peripheral system, Boston XO Clear. OS: 6.62mm base curve, -10.25D power, 16.5mm diameter, standard peripheral system, 4800 sag, HDS100 Blue. When he returned for dispensing of his new scleral lenses, subjectively he reported excellent vision and felt that the smaller left lens was already more comfortable. Visual acuity was 20/25+ OD with a spherical overrefraction of plano DS and 20/25 OS with a spherical overrefraction of +0.50 OS yielding 20/25. Biomicroscopy showed centered lenses with the left lens edge sparing mechanical interaction with the nasal pinguecula. Fluorescein evaluation was not performed. He was asked to return in one week for a contact lens progress visit, and to come in wearing his new scleral contacts for at least an hour. Progress Visit When he returned for his contact lens progress visit, he had been wearing his lenses for three hours and reporting that he was pleased with the new scleral lenses. He estimated that the redness and discomfort in the left eye had resolved by 98% with the smaller diameter scleral lens. For the right eye, there was no appreciable subjective difference in his wearing experience with the new design. Subjective vision was excellent in both eyes, with comfortable wear for full waking hours. Contact lens visual acuity was 20/25+ OD with spherical overrefraction of plano DS, and 20/25 OS with spherical overrefraction of +0.50 OS yielding 20/25+. Biomicroscopy showed the left bulbar conjunctiva had significantly reduced injection and the inflamed nasal pinguecula had subsided in size (Figure 3). There was no significant corneal staining. Fluorescein evaluation with the right scleral lens showed approximately 250 microns of central clearance with a relatively even post-lens tear film extending to the limbal clearance zone. The scleral landing zone was optimal. The left lens showed approximately 150 microns of central clearance, also with an even post-lens tear film extending to the limbal clearance zone. The scleral landing zone was optimal as well. A new left lens was ordered, accounting for the +0.50 overrefraction, and he was released to routine annual examination following the lens exchange. DISCUSSION Pingueculae are the most common conjunctival lesion, occurring in 48% of patients.9 They can mechanically interact with the landing zone of a scleral contact lens, leading to redness and discomfort.7,8 Although prescribing topical corticosteroid therapy would quell the inflammatory component of pingueculitis, it would not eliminate the underlying mechanical interaction against the conjunctival elevation and could require chronic dosing. The risk of chronic corticosteroid therapy, even with the ester-based corticosteroid loteprednol, is the potential for cataract formation and increased IOP.12 For this reason, although suitable as a REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 27 CASE REPORT Photo: Alden Optical periodic adjunct, a more sensible approach is modifying the lens to address the root cause of scleral lens–induced pingueculitis. A review of the literature describes lens-based modifications, such as adding an edge notch on the scleral lens to resolve the problems with pingueculae.7,8,14 However, because these edge notches are introduced using a hand tool, there is variability with lens reproducibility. MicroVaults (Alden Optical)—designed and manufactured with CAD/CAM technology—may overcome the problems of reproducibility found with traditional hand-notching, according to the manufacturer. (Figure 4).15 With both handnotched lenses and MicroVaults, the patient must apply the notches in the proper orientation to correspond with the location of the pinguecula. Finally, although not the case with this patient, hybrid lenses may afford resolution of the mechanical interaction on the pinguecula due to draping of the soft skirt over the conjunctival elevation. As illustrated by this case report, ordering a smaller diameter scleral lens was a simple and effective treatment for this patient’s pingueculitis, particularly because it was peripherally located. The benefit of decreasing lens diameter is that it is simple, can minimize further cost to the patient, and removes the burden of applying the lens with the notch or MicroVault in the same location of the pinguecula. While decreasing diameter may seem an intuitive solution, interestingly, another purported strategy is to prescribe an even larger diameter scleral lens to compress the pinguecula.13 Scleral contact lenses are very well tolerated by most patients Fig. 4. Just like scleral lenses with an edge notch, MicroVault lenses require lens application with rotational registration such that the MicroVault aligns with the conjunctival elevation. with keratoconus due to good comfort and vision, especially when compared to corneal gas permeables and other types of contact lenses.6 The high rate of success of scleral lenses should remind clinicians to educate those with keratoconus about the importance of ultraviolet (UV) light protection to minimize the risk of developing pingueculae. Although the aforementioned modifications to scleral lenses can help patients with pingueculae to remain in scleral lens wear, it is best if patients never develop these conjunctival lesions in the first place. Although UV light may have a therapeutic effect in mitigating keratoconus progression by facilitating collagen crosslinking, it is likely outweighed by the risks of UV exposure, including certain eyelid growths, pingueculae, pterygia, cataract and retinal damage.16 S cleral contact lenses are well tolerated by most keratoconus patients, but conjunctival lesions, including pingueculae, can pose an obstacle to success. For some patients, reducing the lens diameter to eliminate or reduce interaction of the lens edge with the conjunctival lesion—especially if the lesion is located peripherally—is the simplest treatment option. Conversely, for others with pingueculae, enlarging the scleral lens diameter to deliberately compress the conjunctival elevation may help. If 28 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 these treatments are unsatisfactory, edge notching and MicroVaults are the next logical step, which involves greater complexity due to additional position specification of these lens modifications. RCCL 1. Alió JL, Shabayek MH. Corneal higher order aberrations: a method to grade keratoconus. J Refract Surg. 2006;22(6):539-45. 2. Barnett M, Mannis MJ. Contact lenses in the management of keratoconus. Cornea. 2011;30(12):1510-6. 3. Schornack MM, Patel SV. Scleral lenses in the management of keratoconus. Eye Contact Lens. 2010;36(1):39-44. 4. Van der Worp E, Bornman D, Ferreira DL, et al. Modern scleral contact lenses: A review. Cont Lens Anterior Eye. 2014;37(4):240-50. 5. Visser ES, Visser R, van Lier HJ, et al. Modern scleral lenses part II: patient satisfaction. Eye Contact Lens. 2007;31(1):21-5. 6. Bergmanson JPG, Walker MK, Johnson LA. Assessing scleral contact lens satisfaction in a keratoconus population. Optom Vis Sci. 2016;93(8[Epub ahead of print]. 7. Messer M. Getting creative with scleral lenses: Part 1. Review of Cornea & Contact Lenses. 2012;148(1):7. 8. Denaeyer GW. Designing lenses to work around scleral obstacles. Contact Lens Spectrum. August 2012. Available at www.clspectrum.com/articleviewer.aspx?articleID=107286. Accessed May 24, 2016. 9. Viso E, Gude F, Rodríguez-Ares MT. Prevalence of pinguecula and pterygium in a general population in Spain. Eye (Lond). 2011;25(3):350-7. 10. Rabinowitz YS. Keratoconus. Surv. of Ophthalmol. 1998;42:297–319. 11. Visionary Optics. Europa Scleral Overview. Available at www.visionary-optics.com/products/ scleral-lens-for-irregular-corneas/europa-scleral. Accessed May 30, 2026. 12. Comston TL, DeCory HH. Advances in corticosteroid therapy for ocular inflammation: loteprednol etabonate. Int J Inflam. 2012;2012:789623. 13. Barnett M. Case study: scleral lenses post glaucoma surgery. Optometric Management. December 1, 2014. Available at www.optometricmanagement. com/articleviewer.aspx?articleID=112072. Accessed May 24, 2016. 14. Messer B. Utilizing MicroVaults to improve comfort and cosmesis in scleral lens wearers with pingueculae. Poster. Available at www.aldenoptical. com/docs/zenlens/Zenlens_Poster.pdf. Accessed May 24, 2016. 15. Van der Worp E. A guide to scleral lens fitting, Version 2.0 [monograph online]. Forest Grove, OR: Pacific University; 2015:51. Available from: http:// commons.pacificu.edu/mono/10/. 16. Behar-Cohen F, Baillet G, de Ayguavives T, et al. Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF®), a new ultraviolet protection label for eyewear. Clin Ophthalmol. 2014;8:87-104. Advances in Understanding Tear Film Dynamics Let’s gain some perspective on the components, modalities and methodology of dry eye. By Will Smith, OD D ry eye disease (DED) is a massive but often under-appreciated problem. Data suggests as many as 35% of Americans have some degree of DED.1,2 While there is a surfeit of information on DED treatment, diagnosis and observation seem to be the more challenging aspects. The ocular tear film is often observed, but rarely qualified. This qualification is one of the most challenging parts of managing DED. The ocular tear film provides lubrication and visual clarity and is also the first barrier of protection for our eyes. Any vehicle is markedly limited without a windshield, but if the windshield it has is covered in dirt or mud, it is useless. Knowing the anatomical characteristics of the tear film builds the framework for a better understanding of ocular surface disease. TEAR FILM ANATOMY: A REFRESHER All clinicians know that the tear film is comprised of three dynamic layers—mucin, aqueous and lipid—but some of its specifics may elude us in routine practice. The mucin layer is 0.02µm to 0.05µm thick and provides an anchor for tear film foundation, while the aqueous layer resides between both mucin and lipid layers and is the thickest layer, at 0.7µm. The most superficial is the lipid layer, which helps protect the tear film from decomposition.3 Tears are produced from the lacrimal gland under the influence of the parasympathetic and sympathetic nervous system.4 Through dynamic tear film interferometry we know tear fluid is spread over the ocular surface from temporal to the nasal segments of the eye.5,6 The distribution of tears is dependent on lid blink, and facilitation of drainage is through the lacrimal puncta.5,7 The tear film takes one of three outputs: evaporation, drainage or absorption. Evaporation is inevitable, but accelerated by poor lipid tear layer.8 Drainage through the nasolacrimal system can be impeded by anatomical morphology such as scarring or cautery. Absorption is suggested through corneal permeability in the absence of compromised corneal function and is reported as minimal, roughly 15% absorption.9,10 Collectively, the tear film supplies the ocular surface with many nutrients and wound healing properties such as fibronectin, vitamins and growth factors.11 These elements support and modulate proliferation, migration and differentiation of the conjunctival and corneal epithelium. AQUEOUS-DEFICIENT VS. EVAPORATIVE DED The Dry Eye Workshop defined two modalities of DED: aqueous deficient and evaporative.12 Of these two subcategories, evapora- tive dry eye represents the majority of cases.13,14 Evaporative dry eye disease, which results from increased ocular surface exposure and meibomian gland dysfunction (MGD), is commonly associated with an inflammatory process.12 During inflammation, proteins are released into the tears, which serve to support opsonization (i.e., targeting) and phagocytosis of microbes by macrophages and lymphocytes. Ultimately, damage to the meibomian or sebaceous glands comes from androgen dysregulation, microbe invasion and excretory duct obstruction due to hyperkeratinization and increased viscosity of meibum.15,16 Tears serve a lubricating and mechanical clearance function, but also possess epitheliotropic and antimicrobial properties.17,18 The importance of identifying these underlying processes and how they contribute to tear film ABOUT THE AUTHOR Dr. Smith is an optometric physician with a special interest in dry eye management, therapeutic contact lenses and surgical comanagement. Currently, he practices at the Veterans Affairs outpatient clinic in Jacksonville, VA, where there is great demand for emergency eye care and management of chronic ocular disease. Dr. Smith has served as a board member and volunteer for many organizations, including: Volunteer Optometric Services to Humanity (VOSH), Jefferson County Community Participation Board and Equal Access Birmingham. He is a member of Florida Optometric Association and American Optometric Association and is a National Association of Veterans Affairs optometrist. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 29 ADVANCES IN UNDERSTANDING TEAR FILM DYNAMICS Fig. 1. Transillumination of lower lid, showing meibomian gland structure with blue and white arrows. dysfunction cannot be overstated. Diagnostic tools have advanced to allow proper quality assessment of tear film dynamics, and they help to standardize a protocol for diagnosis and management. OBSERVING THE GLANDS Meibomian gland observation can be performed by meiboscopy, interferometry and meibography. Meiboscopy is performed with basic transillumination of the lids (Figure 1).20 Although this method is quick, effective and available to all practitioners, newer techniques and tools provide better visualization of meibomian gland structure. Meibography allows for the evaluation of the number and morphology of the meibomian glands from their point of origin through to the ductal termination at the orifices (Figure 2). There are two principles in meibography: transillumination of the everted lid and direct illumination, or non-contact meibography. Slit-lamp microscopy (Topcon), portable noncontact meibography (Shenzhen LYD Technology), LipiScan (TearScience), LipiView II (TearScience) and Keratography 5M (Oculus) are all instruments designed to perform meibography. Only gross imaging scales exist for grading at this time (Figure 3).21 Although rudimentary, they are effective in documenting baseline meibomian status by comparing the patient’s gland structure with the closest associated grading. Studies show methods of grading meibography images demonstrate good within-reader reliability and fair between-reader reliability.22 Researchers observed normal aging changes of meibomian glands such as acinar (glandular) density reduction and an evident decrease of the acinar diameter without significant modifications of the glandular orifice diameter.23 They also observed morphological changes in disease states; with MGD, acinar density was reduced but diameter was increased, and orifice diameter was dilated.23 Interferometry allows for micro observation of the tear film’s lipid layer. Basic optical theory of reflectance and thin film interferometry can indicate the hue and saturation seen as a function of the thickness of the transparent layer, causing the interference phenomena.24 Lipiview II (TearScience) is the only commercial instrument designed to provide real-time visualization of the lipid layer thickness, lid closure and blink rate with one scan. Research shows a thin lipid layer correlates with dry eye disease symptoms.25 HYPEROSMOLARITY Tear film hyperosmolarity is considered by some researchers to be the primary cause of discomfort, 30 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 ocular surface damage and inflammation in dry eye.26 Osmolarity can be measured with TearLab’s handheld osmometer. A clinical cut-off of 312mOsm is suggested as the diagnostic level for aqueous-deficient and evaporative dry eye.27 Any decrease in meibum or aqueous secretion contributes to increases in osmolarity, thus complicating diagnostic specificity. Researchers evaluated whether tear film osmolarity could be used as a reliable diagnostic tool for dry eye in patients with rheumatoid arthritis (RA). They found that 66% of patients with RA have osmolarity of greater than 316mOsm, serving as an indication for work-up of systemic inflammatory diseases.28 Matrix metalloproteinase-9 (MMP-9)—a nonspecific marker of inflammation—is a proteolytic enzyme that comes from stressed epithelial cells on the ocular surface.29 In healthy control individuals, MMP-9 is normally found at low levels; however, in those with DED, levels rise to more than 40ng/ml.29,30 MMP-9 can be measured by InflammaDry (Rapid Pathogen Screening, RPS). To perform this point-of-care test, swab the palpebral conjunctiva, and place the swab into the RPS Fig. 2. Meibography of normal gland structure (top) and gland truncation or scarring (bottom). Questionnaire Osmolarity (TearLab) Interferometry InflammaDry (RPS) Meibography Schirmer's Slit Lamp Exam (Careful lid evaluation) Staining Fig 4. Example of an ocular surface work-up protocol. cassette, where a buffer is applied to complete the test. Although eye care practitioners have long been able to identify dry eye patients by clinical observation of ocular surface disruption, osmolarity and MMP-9 testing— particularly when used in combination—increase the precision we can bring to our assessment and management plan. Meiboscale Area of Loss Fig. 3. Five-grade meiboscale.14 STANDARDIZED PROTOCOL Diagnostic technologies still lack the ability to determine the ideal course of disease management— that remains a clinical responsibility. As providers, we seek certainty to provide the most targeted and cost effective care. Not all technologies provide equal value, but all increase our knowledge. The best strategy with DED testing is to keep follow-up care consistent with a standardized protocol (Figure 4) that provides information about tear production, ocular surface grade and meibomian gland function. RCCL 1. Improving screening, Diagnosis, And Treatment of Dry Eye Disease: Expert Recommendations From the 2014 Dry Eye Summit. National Eye Institute. Facts about dry eye. Availabe at www. nei.nih.gov/health/dryeye/dryeye. Accessed September 7, 2016. 2. The Epidemiology of Dry Eye Disease: Report of the Epidemiology Subcommittee of the International Dry Eye WorkShop. 2007;5(2):93-107. 3. Creech J, Do L, Ratt I, Radke C. In vivo tear film thickness and implications for tear film stability. Curr Eye Res. 1998 Nov;(11):1058-66. © 2012, 2016 Dr. Heiko Pult — Optometry & Vision Research, Germany, www.heiko-pult-de, used with permission. 4. Dartt DA. Dysfunctional neural regulation of lacrimal gland secretion and its role in the pathogenesis of dry eye syndromes. The Ocular Surface. 2004;2:76-88. 5. Clinch TE, Benedetto DA, Felberg NT, Laibson PR. Schirmer’s test. A closer look. Arch Ophthalmol. 1983;101:1383-6. 6. Doane MG. An instrument for in vivo tear film interferometry. Optom Vis Sci. 1989;66:383-8. 7. Tsubota K. Tear dynamics and dry eye. Prog Retin Eye Res. 1998;17:565-96. 8. Lozato PA, Pisella PJ, Baudouin C. The lipid layer of the lacrimal tear film: physiology and pathology. J Fr Ophtalmol. 2001;24(6):643-58. 9. Joshi A, Maurice DM, Paugh JR. A new method for determining corneal epithelial barrier to fluorescein in humans. Invest Ophthalmol Vis Sci. 1996;37:1008-16. 10. Goebbels M, Spitznas M. Corneal epithelial permeability of dry eyes before and after treatment with artificial tears. Ophthalmology. 1992;99:873-8. 11. Geerling G, MacLennan S, Hartwig D. Autologous serum eyedrops for ocular surface disorders. Br J Ophthalmol. 2004;88(11):1467–74. 12. The definition and classification of dry eye disease: report of the Definition and classification Subcommitee of the International Dry Eye WorkShop. Ocul Surf. 2007;5(2):75-92. 13. Shimazaki J, Sakata M, Tsubota D. Ocular surface changes and discomfort in patients with Meibomian gland dysfunction. Arch Ophthalmol. 1995;113:1266-70. 14. Lemp M, Crews L, Ron A, et al. Distribution of aqueous deficient and evaporative dry eye in a clinic-based patient population. Cornea. 2012 May;31(5):472-8. 15. Gilbard JP. The diagnosis and management of dry eyes. Otolargngol Clin N Am. 2005;38;5:87185. 16. Thody AJ, Shuster S. Control and function of sebaceous glands. Physiol Rev. 1989;69:383-416. 17. Sullivan D, Sullivan BD, Ullman MD, et al. Androgen influence on the meibomian gland. Invest Ophthalmol Vis Sci. 2000;41:3732-42. 18. Ng V, Cho P, Mak S, Lee A. Variability of tear protein levels in normal young adults: between-day variation. Graefes Arch Clin Exp Ophthalmol. 2000;238:892–9. 19. Liu S, Richards S, Lo K, et al. Changes in gene expression in human meibomian gland dysfunction. Inv Ophthmol Vis Sci. 2011;52:272-4. 20. Tapie R. Etude biomicroscopique des glandes de meibomius. Ann Oculistique. 1977;210:637–48. 21. Pult H, Riede-Pult B. Neues zur Meibographie. Die Kontaktlinse. 2011;6:24–5. 22. Nichols JJ, Berntsen DA, Mitchell GL, Nichols KK. An assessment of grading scales for meibography images. Cornea. 2005;24:382–8. 23. Fasanella V, Agnifili L, Mastropasqua R, et al. In vivo laser scanning confocal microscopy of human meibomian glands in aging and ocular surface diseases. Biomed Res Int. 2016;7432131. 24. Doane M, Lee E. Tear film interferometry as a diagnostic tool for evaluating normal and dryeye tear film. In: Lacrimal gland, tear film, and dry eye syndromes 2. 1998;438:297-303. 25. Tomlinson A, Khanai S. Assessment of tear film dynamics: quanification approach. 2005;3(2):81-95. 26. Blackie CA, Solomon JD, Scaffidi RC, et al. The relationship between dry eye symptoms and lipid layer thickness. Cornea. 2009;28(7):789-94. 27. Gilbard JP, Farris RL, Santamaria J 2nd. Osomolarity of tear microvolumes in keratoconjunctivitis sicca. Arch Ophthalmol. 1978;96:688-91. 28. Schargus M, Wolf F, Tony H, et al. Correlation between tear film osmolarity, dry eye disease, and rheumatoid arthritis. Cornea. 2014;33:125761. 29. Chotikavanich S, de Paiva CS, Li de Q, et al. Production and activity of MMP-9 on the ocular surface increase in DTS. Invest Ophthalmol Vis Sci. 2009;50:3203-9. 30. Acera A, Rocha G, Vecino E, et al. Inflammatory markers in the tears of patients with OSD. Ophthalmic Res. 2008;40:315-21. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 31 Practice Progress By Mile Brujic, OD, and Jason Miller, OD, MBA Breaking Habits Remain current with technological advancement so your patients and practices can thrive. W hile new technology is exciting at first glance, it often fails to make a lasting impact in our practices. Many of us forget about new technological advancements, falling back into our comfort zone, particularly with contact lens fits. But early adopters to change will develop the culture of “being ahead of the curve” and reap the rewards of increased revenue for that technology. Many of us have heard the phrase, “if it’s not broke, don’t fix it.” While that holds true for some scenarios, it’s not always the smartest approach to contact lens fitting. It’s worth taking a broader perspective that incorporates technological advancement when addressing certain contact lens situations. You may find a better way of doing things. This month, we look at two cases and discuss ways to break some habits many of us may have developed over time—regardless of efficacy. CASE 1: CHILDREN AND CONTACT LENSES A 10-year-old male patient wants to start wearing contact lenses. His myopic correction has just jumped from a -1.00DS OU to a -2.00DS OU in the past eight months. Old habits. The most familiar method for this case would be to discuss the various options of contact lenses—from dailies to the reusable two-week or one-month modalities. After that discussion, let the parents decide what they think would work best for their child. Without any information on the differences between CLs, most patients would choose the least costly modality. New habits. If, on the other hand, we incorporate a broader End-of-day dryness and limbal injection from significant digital device use demonstrates signs of contact lens-related complications. 32 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 perspective and take into account the current state of technology, we would start with making a strong recommendation for the new, innovative daily disposable lenses. Research demonstrates that three in five contact lens wearers do not wash their hands prior to handling the lenses.1 The minimized handling that comes with daily disposable lenses is just one reason they are the healthiest and most convenient choice and are now considered the lens of choice for this younger population. Next, consider taking a step further to discuss contact lenses for myopia control. It is proving worth our time to educate patients (or their parents) on certain contact lens options now available that are beneficial for slowing refractive changes at a young age. Myopia control contact lenses offer much promise and may be the next big thing in the contact lens industry. This area is one of untapped potential and could form the foundation for future treatments for children with developing myopia. Many studies are currently looking at the possibilities, but if we could tell parents they could reduce their child’s vision impairment by a certain percentage (working toward a design or treatment that would reduce myopia by 50%), that would be a drastic improvement worth exploring. These lenses work by slowing down the patient’s predicted axial length elongation. Through a complicated process, the peripheral retina can mediate refractive development centrally. The peripheral Photo: Paul M. Karpecki, OD Dryness from incomplete blinks can happen at any age, especially for digital device users. hyperopia can be a stimulus and may even precede the development of myopia. Current theories are aimed at preventing this peripheral defocus at an early age.2 Questions obviously remain, but many researchers are evaluating the role of genetic predisposition, amount of near work, lag of accommodation, vitamin D levels and the amount of time spent outdoors.3,4 Other new treatments such as light filtering spectacle lenses, soft or rigid bifocal or multifocal contact lenses, orthokeratology lenses and pharmaceutical agents (atropine, pirenzepine, 7-methylxanthine) are under thorough evaluation. As eye care professionals, we see similar cases on a daily basis. Having the tools, technology and research to back up our recommendations is critical. Don’t get stuck in the same old habits or wait too long. CASE 2: DIGITAL DEVICE USER A 30-year-old female patient is currently wearing monthly disposable contact lenses and wants to renew her contact lens prescription. She says she is happy with her current lenses. Old habits. The most familiar route would consist of performing the examination, checking the patient’s refraction and renewing the same prescription. Rather than trying to upgrade the patient into a newer contact lens technology, it is often quicker and easier to just renew the prescription if everything looks up to par and the patient has no complaints. This is, unfortunately, the more common approach in many offices. New habits. If we want to remain ahead of the curve and consider the best option available to us, we should start by getting the whole story. Upon further questioning, you find out that this patient works at a bank and spends eight to 10 hours a day on the computer. She has intermittent blurriness (due to a reduced blink rate and incomplete blinking) throughout the day and her eyes look red at the end of the day. The general consensus, after a more thorough session, would be that our patient’s current contact lens regimen is not, in fact, good at all. As a result of extensive digital device use, today’s patients put new visual health demands on their eyes. Despite all of the advances in contact lens technology, patient discomfort remains a problem. Many are reticent to complain and would rather continue with what they have than deal with alternatives. Patients often imagine the worst, and so avoid confronting the idea of change. This case provides a great oppor- tunity to upgrade the patient into more technologically advanced contact lenses. Patients need a contact lens that can provide all-day visual clarity and comfort. Instead of providing the same contact lens prescription, consider refitting this patient in a newer design and modality. Many new daily disposable contact lenses have moisture agents embedded in the matrix of the contact lens to help reduce end-of-day dryness and improve all-day comfort. Additionally, consider using a lens that provides improved optical correction while on the computer. This may be an aspheric or a low multifocal design to help with the accommodative demand throughout the day. E ye care professionals can choose from a wide variety of contact lens materials, designs and modalities that can improve ocular health and visual clarity. Innovative products and research will continue to drive the market. It is vital we stay current with ongoing research in an attempt to break old habits and integrate new and improved methodologies into our practices—a shift that is sure to provide improved health to our patients and growth to our practices. RCCL 1. Stone R. The importance of compliance: focusing on the key steps. Poster presented at the annual meeting of the British Contact Lens Association; May 31-June 2, 2007. 2. Mutti DO, Sholtz RI, Friedman NE, Zadnik K. Peripheral refraction and ocular shape in children. Invest Ophthalmol Vis Sci. 2000:41(5):1022-30. 3. Mutti DO, Marks AR. Blood levels of vitamin D in teens and young adults with myopia. Optom Vis Sci. 2011;88:377-82. 4. Mutti DO, Mitchell GL, Sinnott LT, et al. Corneal and crystalline lens dimensions before and after myopia onset. Optom Vis Sci. 2012;89:251-62. REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 33 Out of the Box By Gary Gerber, OD Four Keys to Building Your Practice These commonalities indicate you are ready to venture out on your own—and that you will be successful when you do. O ver the last few years, our consulting company has helped an array of doctors start their own practices. Many are transitioning from corporate to private practice, while others are working for ODs and are now ready to venture out on their own. Looking back on these practices and seeing what they did to become successful made me realize they all had four things in common: 1. BUILD A STRONG BRAND They know who they are and what they want. More specifically, they have a strong brand, mission and optical providers offer frames not readily found elsewhere, making the buying experience distinctive. 2. BECOME A GREAT LEADER These doctors are great leaders. Many are naturals, but most aren’t. Rather, most became great leaders by staying hyper-focused on their brands to ensure every employee is keyed in to the specific nature of the practice. So, instead of just holding a staff meeting and saying, “We are going to change the way we book appointments from Y to Z,” they use this as a brand teaching moment: “Because our brand is about X, and because every decision and GET FOCUSED, EMPLOY A TEAM INVESTED IN YOUR BRAND AND REMAIN APPROACHABLE—THEN WATCH YOUR PRACTICE THRIVE. values. These practices unequivocally stand for something. They are known in their communities for doing one particular thing better than other practices. That one thing may be clinical (specialty contact lenses, dry eye treatment or pediatrics) or experiential (exemplary, memorable service; unique optical selection; strong involvement in the community). Notably, they are willing to perform this métier to the exclusion of others. For example, specialty lens practices de-emphasize eyeglass offerings to increase referrals from other practitioners, and pediatric practices don’t see adults. Unique fiber of this practice involves some component of X, we are changing the way we book appointments from Y to Z.” When staff members overhear these leaders talking to patients, sales reps, family or friends, the brand messaging is infused in every conversation. They set an example of what it means to live the brand. From that, their staff sees an unwavering commitment to the practice brand and values, which results in a staff that wants to be a part of something meaningful. 3. WELCOME CHANGE Change is welcomed, encouraged 34 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 and happens quickly. Staff members are constantly challenged to offer suggestions on how to improve the brand. Even though most of these practices open their doors with only one staff member, that person isn’t simply a robot tasked with answering the phones and verifying insurance claims. Rather, they are a source of new ideas—which are always solicited and genuinely welcomed. If that person rarely has new ideas, they are quickly replaced. While training new staff is never an easy task, it’s usually easier for new practices because of the extra time available. Smart owners use this downtime to train staff on technical aspects of their own culture and brands. 4. AVOID BUREAUCRACY As these practices grow, they do so with the mindful intent of avoiding an impenetrable bureaucracy. The owner creates a culture in which they are always an approachable, brand-savvy CEO without adding barriers and layers of documents and policies that would stunt growth. There are fewer departments and managers in these practices than others, and their teams work better together without the stifling corporate structure. T hese four characteristics mark successful transitions into private practice. Reviewing them can shed light for other ODs wishing to branch out into their own practice. Get focused, employ a team invested in your brand and remain approachable—then watch your practice thrive. RCCL Exceptional comfort unites with a proven multifocal design INTTRODUCING G ® Bausch + Lomb ULTRA for Presbyopia MoistureSeal® technology • Helps maintain 95% of lens moisture for a full 16 hours1 Provide your patients clarity through consistency Learn more at www.Bausch.com/UFP 3-Zone Progressive™ Design • Provides outstanding near, intermediate, and distance vision2 • Offers easy, predictable fitting where 80% of patients were successfully fit in one visit2,3* *When the ECP followed the fitting guide for the 3-Zone Progressive™ Design of PureVision®2 for Presbyopia lens. REFERENCES: 1. Data on file. Bausch & Lomb Incorporated. Rochester, NY; 2013. 2. Data on file. Bausch & Lomb Incorporated. Rochester, NY; 2015. 3. Thirty-nine ECPs (from 10 countries) refitted 422 existing soft contact lens wearing presbyopes into PureVision®2 Presbyopia lenses. Patients returned for follow-up visits after 1-2 weeks. ECP assessment of lens performance including ease of fit, and patient satisfaction with lenses in real-world conditions, were measured using a 6-point agreement survey. Bausch + Lomb ULTRA, MoistureSeal, PureVision, and 3-Zone Progressive are trademarks of Bausch & Lomb Incorporated or its affiliates. ©2016 Bausch & Lomb Incorporated. UFP.0146.USA.16 RO0516_B & L Ultra.indd 1 4/25/16 11:45 AM The most comprehensive GP lens care system available. Introducing LacriPure Menicon’s new rinsing and insertion saline solution. Indicated for use with soft, hybrid and rigid gas permeable lenses, LacriPure is a sterile, non-preserved saline which provides an alternative to tap water rinsing. Packaged in a 5ml unit-dose vial, LacriPure has been cleared as a scleral lens insertion solution and provides the patient with exceptional sterility. 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