Download Optometry*s Role in Laser Vision Correction

By The Right Contact Team
http://www.therightcontact.com
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Although optometrists do not perform laser
vision correction here in the United States, they
can still provide a valuable role in this procedure
that is gaining unprecedented popularity.
According to recent data, a record 16 million
people have had LASIK vision correction in the US
though 20111.
This is an amazing opportunity for optometry.
Whether it is screening good candidates, comanaging post-ops or managing complications,
there is a lot the optometric profession has to
offer.
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LASIK
Wavefront LASIK
Intralase
LASEK
EPI-LASEK
PRK
 Pre-Op
 Post-Op
 Complications
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There many issues that a practitioner should
review when considering candidacy for laser
vision correction.
The following are a few concerns to be
addressed prior to referring the patient for
the procedure.
◦ Candidacy as defined by the FDA
◦ Anterior surface concerns
◦ Patient habits
Who is a good candidate for laser vision correction?
Since its FDA approval in 19952, many factors have remained
unchanged
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INDICATIONS
*Age 18 years of age or older with stable refraction for one year.
*Myopia (nearsightedness) up to -14 diopters either without astigmatism or from -0.5 to -5
diopters of astigmatism
*Hyperopia (farsightedness) from +1 to +4.5 diopters with less than 1 diopters of astigmatism
*No history of eye disease, corneal scarring or retinal problems
*Not pregnant or nursing for 3 months and not planning a pregnancy in the 3 months
following surgery
CONTRAINDICATIONS
Laser refractive surgery is contraindicated:
* in patients with collagen vascular, autoimmune or immunodeficiency diseases.
* in pregnant or nursing women.
* in patients with signs of keratoconus or abnormal corneal topography
* in patients who are taking one or both of the following medications: isotretinoin (Accutane®)
or amiodarone hydrochloride (Cordarone®).
Dry Eye
 Ideally you want to identify dry eye during the pre-op period
 Spend at least a few weeks to months treating it.
 Utilizing tools such as artificial tears, punctal plugs, cyclosporine
eye drops and nutritional therapy (omega-3 fatty acids) 3 can
prove very useful.
Blepharitis
 Laser vision correction causes significant inflammation in normal
eyes. Consider the consequences surgery can have when
handling patients that already suffer from anterior surface
disease.
 Treatment options include
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oral tetracycline
topical macrolide antibiotics
combination steroid/antibiotic drops
nutritional options (such as flaxseed oil).
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Does the patient work or live in environments
of excessive heat?
Does the patient suffer from allergies or
habits that pre-dispose them to eye rubbing?
Avoiding these issues can greatly
affect the potential outcome of
the procedure.
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Most surgeons recommend a very specific
follow-up schedule to ensure proper healing.
An average schedule would include
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1st day
1st week
1st month
3 – 6 months
Each post-op appointment has very specific
concerns that are to be addressed.
Each visit should take the opportunity to reeducate the patient on their status and the
overall healing process.
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During this visit, the practitioner will access vision and make a
corneal evaluation. The corneal evaluation will obviously vary
depending on the procedure performed.
◦ If the patient has undergone LASIK, than flap evaluation will take place.
◦ If PRK or LASEK was performed, the corneal evaluation will be done under
the bandage contact lens.
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Patient instruction is very specific at this visit.
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Aggressive rubbing should be addressed.
◦ Remind the PRK and LASEK patients that discomfort within the first few
days is common but will subside. After a discussion about all topical
post-op medications, patient’s activities need to be discussed.
◦ The patient should be discouraged from performing any tasks that could
potentially hit the eye. Be specific, state avoiding things like water striking
the eye during bathing, make-up (no mascara or eyeliner), sports, and
exercise. The patient should wear a protective shield at night. Provided
the vision is adequate, the patient is definitely able to resume deskwork or
driving immediately.
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At this visit a re-assessment of vision and
corneal integrity is taken.
As compared to their first post-op, patients
that underwent PRK and LASEK should note a
dramatic increase in comfort and vision.
Many times topical medications are
discontinued at this visit.
The patient is often informed that they can
begin a moderate level of activities including
exercise, swimming, hot tubs and contact
sports.
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The 1 month post-op evaluation again
evaluates the vision and corneal surface.
At this stage the cornea should be completely
attached and the patient is able to resume all
activities.
◦ These activities would include those that were
previously restricted such as gardening, scuba
diving, etc.
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These visits are routine health evaluations.
At this time, many doctors will have to
manage issues associated with dryness.
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When discussing any type of surgery you
always have to be aware of the risks
associated with the procedure.
Even though laser vision correction has a very
good track record, sometimes there are
unfortunate results that have to be
addressed.
The following is a listing of possible
complications that can occur with laser vision
correction.
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Doctors are trained not to be over concerned about
initial signs of overcorrection.
◦ This is because immediate post-ops can show correction
issues secondary to expected corneal swelling.
◦ The patient should be educated that these symptoms will
subside within a few days to two weeks.
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Despite extensive pre-testing, sometimes the eyes do
not respond in a predictable fashion. Regardless of
the reason, the patient still has options.
◦ If the patient is interested in additional surgery, an
enhancement may be considered.
◦ Non-surgical treatment options include glasses and
contacts.
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Visual distortion can arise from several areas.
Quite often this is related to the size of the
treatment zone5.
◦ If the pupil is wider than the treatment zone the
patients may report glare or haze.
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Retreatment is a possibility, but optic zone
size can also be addressed with topical drops.
◦ The patient may be given a drop that has mitotic
effects for things like night driving.
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Wrinkles
Epithelial Ingrowth
DLK (Diffuse Lamellar Keratitis)
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During surgery, if the flap is not made correctly,
either to thin or to thick, it may not correctly
adhere to the corneal surface.
◦ This can cause microscopic wrinkles, or striae which will
interfere with the patient’s visual outcome.
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Wrinkles may also occur due to patient
compliance issues. A patients rubbing or
squeezing the eye too tightly within the first few
hours of the procedure could also result in
wrinkles.
◦ Patients should be discouraged from this behavior for
the first 24-48 hours after the procedure.
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Epithelial ingrowth is another rare but
potentially serious complication.
◦ Studies continue to show that early detection is
vital.
◦ The use of optical coherence tomography has
proven to be a useful tool in diagnosing this
abnormal finding6.
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Not all cases of epithelial ingrowth need to be
treated and therefore careful monitoring is
required.
Surgical removal of epithelial accumulation is
indicated before the formation of a scar7.
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Diffuse lamellar keratitis (Sands of Sahara) is accumulation of white
blood cells between the flap and stroma. These cells develop at the
stromal interface and create unwanted inflammation.
◦ This presentation is usually evident 1-5 days after LASIK but can occur many months
after the procedure8.
◦ With slit-lamp evaluation this finding appears as waves of sand.
◦ Patients present with pain, photophobia, foreign body sensation, and /or decreased
vision.
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The cause of diffuse lamellar keratitis is unknown.
◦ These infiltrates are sterile, but the cornea attacks them causing serious damage.
Because these infiltrates are not alive, these cells are able to elude proper sterilization
techniques.
Quick diagnosis is a must, and topical or oral treatment is often
adequate. Common treatment would include topical antibiotics and
steroids.
◦ Accepted dosaging is every 2 hours on both, and possibly an ointment at night.
◦ If topical treatment is inadequate re-lifting the flap, and removal of the infiltrates
may be required.
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Subconjuntival hemorrhages
◦ These often occur with no long term side effects.
◦ No topical treatment is required.
◦ The most important issue would be educating the
patient on its presentation.
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Keratectasia is a very difficult complication to
mange. This finding results in an increase in
refractive error due to the progressive
steepening of the cornea9.
Corneal ectasia can occur as quickly as one
week after the procedure but can also
manifest several years post-operatively.
Managing this condition may eventually begin
with specialty contact lenses, but may mature
to the need for additional surgery like a
penetrating keratoplasty or intacs10.
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Technology continues to advance. One of the more recent
advances would involve wave front technology. These
methods now allow for an extremely precise individualized
vision correction.
◦ The procedure addresses higher order aberrations, something
earlier designs couldn’t come close to affecting.
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Post-operative care is also being modified. Researchers
are looking at developing contact lenses designed to
release a continuous supply of medication during the
post-op period. These designs use vitamin E to help
release the drugs automatically overtime11.
Although optometrists cannot perform
the procedure, as you can see, we can
play quite an active role in the patient
pre- and post care.
1. 2011 Market Scope, LLC
2. FDA. (2010). FDA-Approved Lasers for PRK and Other Refractive Surgeries. Retrieved from
http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/SurgeryandLifeSupport/LASIK/ucm192110.htm
3. Saadia Rashid, MD; Yiping Jin, MD, PhD; Tatiana Ecoiffier, MSc; Stefano Barabino, MD, PhD; Debra A. Schaumberg, ScD, MPH; M. Reza Dana, MD, MSc, MPH. Topical Omega-3 and
Omega-6 Fatty Acids for Treatment of Dry Eye. Arch Ophthalmol. 2008;126(2):219-225.
4. Goldman D. Treating blepharitis to maximize surgical success. Cataract Refractive Surgery Today. 2009 May:61-3.
5. Gregory W. Schmidt, MD; Michael Yoon, MD; Gerald McGwin, PhD; Paul P. Lee, MD, JD; Stephen D. McLeod, MD. Evaluation of the Relationship Between Ablation Diameter, Pupil
Size, and Visual Function With Vision-Specific Quality-of-Life Measures After Laser In Situ Keratomileusis. Arch Ophthalmol. 2007;125(8):1037-1042.
6. Alissa Coyne, O.D., and Joseph Shovlin, O.D.AS-OCT Technology: Analyzing the Anterior Segment. Review of Optometry. Continuing Education. April 2012;
7. Irene Naoumidi, PhD; Thekla Papadaki, MD; Ioannis Zacharopoulos, MD; Charalambos Siganos, MD, PhD; Ioannis Pallikaris, MD, PhD. Epithelial Ingrowth After Laser In Situ
KeratomileusisA Histopathologic Study in Human Corneas. Arch Ophthalmol. 2003;121(7):950-955.
8. Bennie H. Jeng, MD; Jay M. Stewart, MD; Stephen D. McLeod, MD; David G. Hwang, MD. Relapsing Diffuse Lamellar Keratitis After Laser In Situ KeratomileusisAssociated With
Recurrent Erosion Syndrome. Arch Ophthalmol. 2004;122(3):396-398.
9. Beeran Meghpara, BA; Hiroshi Nakamura, MD; Marian Macsai, MD; Joel Sugar, MD; Ahmed Hidayat, MD; Beatrice Y. J. T. Yue, PhD; Deepak P. Edward, MD. Keratectasia After Laser In
Situ KeratomileusisA Histopathologic and Immunohistochemical Study. Arch Ophthalmol. 2008;126(12):1655-1663.
10. George D. Kymionis, MD, PhD; Charalambos S. Siganos, MD, PhD; George Kounis, BSc; Nikolaos Astyrakakis, OD; Maria I. Kalyvianaki, MD; Ioannis G. Pallikaris, MD, PhD.
Management of Post-LASIK Corneal Ectasia With Intacs InsertsOne-Year Results. Arch Ophthalmol. 2003;121(3):322-326.
11. Peng CC, Burke MT, Chauhan A. Transport of topical anesthetics in vitamin e loaded silicone hydrogel contact lenses. Langmuir. 2012 Jan 17;28(2):1478-87. Epub 2011 Dec 22.