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Global issues ijor shifts in corneal transplantation procedures in north China: 5316 over 12 years L Xie, F Qi, H Gao, T Wang, W Shi, J Zhao State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Qingdao, PR China Correspondence to: Dr L Xie, Shandong Eye Institute, 5 Yanerdao Road, Qingdao 266071, PR China; [email protected] Accepted 7 May 2009 Published Online First 24 June 200S ABSTRACT ^ Aims: To investigate the major shifts in the ratio of lamellar keratoplasty (LKP) to penetrating keratoplasty (PKP) and in the preoperative indications for each procedure. Methods: Medical records of patients who received LKP and/or PKP at Shandong Eye Institute between 1996 and 2007 were categorised and reviewed. The time period was divided into intervals of 1996-8,1999-2001, 20024 and 2005-7. Results: A total of 4346 patients (5316 eyes) with integrated clinical records were included in the study. LKPs and PKPs were performed on 1558 eyes (29.3%) and 3758 eyes (70.7%), respectively. Within the first 3-year interval, the top three indications for LKP were chemical burns, keratoconus and corneal dermoid; the top reasons for PKP were viral keratitis, suppurative keratitis and corneal scarring. Within the last interval, suppurative keratitis, keratoconus and viral keratitis became most common indications for LKP and suppurative keratitis, viral keratitis and bullous keratopathy for PKP. The ratio of LKP to PKP operations tended to increase. Conclusion: Following proper indications, the use of LKP has increased in number in north China and has become particularly frequent in the management of corneal infections, keratoconus, corneal degeneration, and stro-mal dystrophy. Corneal transplantations are the main procedures performed to treat corneal blindness. Traditionally, penetrating keratoplasty (PKP) has been the procedure selected for corneal diseases such as suppurative keratitis, keratoconus and corneal stromal dystrophy. However, immune rejection, which can lead to graft opacity, remains a major problem after PKP. Even "normal" graft may have chronic corneal allograft dysfunction.' With the accumulation of knowledge on corneal diseases, corneal endothelia and corneal surgery procedures, as well as the development of microsurgical technology, lamellar keratoplasty (LKP) has become more valued. Although today it is well accepted that LKP should be preferred over PKP in as many cases without major problems with the corneal endothelia as it is possible to prevent endothelium-related problems such as immune rejection and chronic corneal allograft dysfunction, we have not yet seen a clinical report with a large number of cases to support the existence of this shift. To track this spontaneous change in procedure preference, we retrospectively reviewed the corneal transplantation cases from Shandong Eye Institute over 12 years and evaluated procedural shifts and indications for each operative procedure. fir J Ophthalmol 2009:93:1291-1295. doi:10.1136/bjo.2008.148981 METHODS Medical records of patients who received corneal transplantation at Shandong Eye Institute, including Qingdao Eye Hospital and Shandong Eye Hospital, from January 1996 to December 2007 were reviewed. Shandong Eye Institute is an important clinical centre for corneal diseases in north China, with patients mainly from across the northern provinces. The corneal diseases were categorised into suppurative keratitis (fungal, bacterial and amoebic infections), viral and other keratitis (viral infection, Mooren ulcer and stromal keratitis), corneal degeneration, dystrophy and congenital anomaly, keratoconus, corneal injury and others.2 All data were divided into four time intervals according to the admission date: January 1996 to December 1998, January 1999 to December 2001, January 2002 to December 2004 and January 2005 to December 2007. Clinical features of patients, preoperative diagnosis and surgical procedure were collected. Proportions of LKP versus PKP within each interval and major preoperative diagnoses were analysed. The f2 test was used for statistical analysis with SPSS10.0. A p value of less than 0.05 was considered statistically significant. RESULTS A total of 4346 patients (5316 eyes) were included. They were 1312 women and 3034 men, aged from 6 months to 91 years. LKP and PKP were performed on 1558 eyes (29.3%) and 3758 eyes (70.7%), respectively. Changes in procedural preference There were 982 corneal transplantations including 236 LKPs (24.0%) and 746 PKPs (76.0%) during the period 1996-8, 1300 transplantations including 352 LKPs (27.1%,) and 948 PKPs (72.9%) during 1999 and 2001, 1641 transplantations including 438 LKPs (26.7%) and 1203 PKPs (73.3%) during 2002 and 2004, and 1393 transplantations including 532 LKPs (38.2%) and 861 PKPs (61.8%) during 2005 and 2007 (x,2 = 74.79, p = 0.00). The proportions of LKP to PKP increased (figs 1, 2). Trends in major preoperative diagnoses Over the 12 years, 1631 eyes with suppurative keratitis underwent corneal transplantation, including 1046 eyes (64.1%) with fungal keratitis, 563 (34.5%) with bacterial keratitis and 22 (1.3%) with amoebic keratitis. Across the four time intervals, LKP was given in 7.5%, 33.7%, 29.9% and 36.9% of eyes with fungal infection (^=47.70, p<0.01), 7.6%, 32.3%, 30.8% and 1291 Clinica Spectacle use after routine cataract surgery M R Wilkins,1 B Allan,1 G Rubin,1'2 Moorfields IOL Study Group ' Moorfields Eye Hospital, 2 London, UK; UCL Institute of Ophthalmology, NIHR Faculty, Biomedical Research Centre for Ophthalmology, London, UK Correspondence to: Or M Wilkins, Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK; [email protected] Accepted 13-March 2009 Published Online First 7 May 2009 ABSTRACT Aims: To measure spectacle dependence following bilateral monofocal intraocular lens (IOL) implantation and assess how it is predicted by postoperative refraction. Methods: 300 cataract patients had bilateral phacoemulsification surgery with monofocal IOL implantation. A spherical equivalent of 0 to -0.5 D was targeted. Three months after surgery, patients answered a questionnaire and had a spectacle refraction. Refractions were converted into vector notation. Logistic regression was used to evaluate whether spectacle dependence for near and distance was related to overall refractive error, spherical error, signed spherical error and astigmatic error. Results: 169 patients attended for assessment. 38 wore distance glasses, and 160 wore reading glasses either some or all of the time. The mean right spherical equivalent was —0.03 D, and the mean right cylinder was —0.64 D. Left outcomes were similar. Patients were 34 times more likely to always use distance glasses per dioptre of astigmatic error in the better eye (p<0.003), but there was no significant increase in the likelihood of wearing distance glasses with spherical error (odds ratio = 3,85, p>0.15). Similar effects were seen for both the better and worse eyes. Nearspectacle use was not dependent on astigmatic error (odds ratio = 0.22, p> 0.12). It was only related to the signed spherical error in the worse eye with hypermetropic patients 6.74 times more likely to always wear spectacles per dioptre of positive spherical error (p<0.005). Conclusions: Following bilateral monofocal intraocular lens implantation, small levels of overall refractive error, in either eye, particularly astigmatism, predict distance-spectacle dependence, whereas spherical ammetropia in the range of +1.0 D does not. Hypemnetropia in the worse eye, but not astigmatism, predicts reading-spectacle dependence. The standard treatment tor patients undergoing routine cataract surgery is to insert a monofocal or fixed focus intraocular lens (IOL). When inserting such an IOL we frequently select an IOL power that will leave the patient with an emmetropic or low myopic prescription. Following bilateral pha-coemulsification surgery where emmetropia has been targeted, spectacle dependence for distance is at least 40%.'2 What is not clear is what factors in the postoperative refraction predict whether a patient will be spectacledependent for near or distance. Knowledge of such factors would allow the surgeon, by changing the IOL power selected, or by managing preoperative astigmatism, to reduce spectacle dependence. routine bilateral sequential phacoemulsification. Three hundred cataract patients were entered into a prospective study of visual outcomes after bilateral cataract surgery. Patients were randomised to sequential implantation with either the Tecnis Z9000 or the Acrysof MA60AC monofocal intraocular lenses. Computer-generated randomisation using a non-blocked coin-toss protocol was used to allocate patients to sequential bilateral implantation of the Z9000 IOL or MA60AC IOL. A spherical equivalent from 0 to -0.5 D was targeted in each eye. This study has been reported in detail elsewhere.3 Inclusion criteria were: age 30 years and above and presence of bilateral visually significant cataracts. Exclusion criteria were: ocular co-pathology which might influence postoperative vision, congenital cataracts or a history indicative of amblyo-pia and preoperative astigmatism greater than 1.5 D as measured by the lOLMaster keratometer. Wherever cataract density permitted, biometry was performed using the lOLMaster; otherwise A-scan biometry was performed. Manufacturers' ultrasound A constants were used throughout. Information on the biometry technique used was retrospectively collected by examining the notes. Four months after the second eye was operated on, patients were interviewed about whether they wore spectacles for near and distance visual tasks and underwent a subjective refraction. Patients were asked whether they wore distancespectacles "always," "tor driving/TV only" or "never." They were also asked if they wore reading glasses "always," "for fine print only," or "never." Binocular uncorrected visual acuity (UCVA) and binocular best spectacle corrected visual acuity (BSCVA) were tested using Early Treatment of Diabetic Retinopathy Study (ETDRS) log minimum angle of resolution (logMAR) letter charts projected on a high-resolution liquid crystal display 4 m from the subject. Refractions were performed by two trained ophthalmic technicians, using a precise protocol. The duochrome technique was not used. All retractions were recorded in minus cylinder format. Near acuities were not recorded, as the original primary aim of the study was to assess the effect of two IOL designs on distance visionrelated quality of life. Spherocylindrical powers were converted to a threedimensional vector notation that included astigmatism and sphere powers (M, Jo and ]^}.' The spherical error (M) refers to the spherical equivalent; JO and J45 refer to Jackson crossed cylinders with orientations of 0 and 45° respectively. The values for M, Jo and ]4s specify a point in space, and the distance of this point from the origin represents overall refractive error (D). The astigmatic error (J) is half the cylindrical power. METHODS T.-,i3 study is an analysis of data collected from a ;:^dv to examine vision-related quality of life after ^•B-..- 1307 Ten years after photorefractive keratectomy (PRK) and Saser in situ keratomileusis (LASIK) for moderate to high myopia (control-matched study) Institute Oftalmologico de Alicante, Vissum (Department of Refractive Surgery) and Division of Ophthalmology, Miguel Hernandez University, Medical School, Alicante, Spain; Ankara University School of Medicine, Ankara, Turkey Correspondence to: Professor J L Alio, Institute Oftalmologico de Alicante Avda De Denia s/n, |EdificioVISSUM) 03016, Alicante, Spain; [email protected] Accepted 31 January 2008 Published Online First 3 December 2008 J L Alio,1 D Ortiz,1 0 Muftuoglu,2 M J Garcia1 threatening.6 7 Consequently, excimer laser superficial ABSTRACT keratectomy techniques such as photorefractive keratectomy Objective: To compare the long(FRK), laser subepithelial keratectomy (LASEK) and term outcomes of photorefractive epithelial laser in situ keratomileusis (Epi-LASIK) have gained popularity in recent years to correct myopia to refrain keratectomy (PRK) and laser in situ from possible complications of LASIK such as corneal keratomilesis (LASIK) for myopia ectasia.4 a 9 between -6 and -10 D. Given that refractive surgery is mostly performed on Methods: A retrospective, control- young and healthy eyes of patients with high expectations, matched study including 68 eyes, 34 long-term safety and which underwent PRK and 34 LASIK, with myopia between -6 and 10 D, operated using the VISX 20/20 excimer laser, was performed. Optical zones of 5.5 to 6 mm were used. All PRK-treated eyes were matched with LASIK-treated eyes of the same age, spherical equivalent within ±1.25 D, sphere within ±1.5 D and cylinder within ±2.5 D. All patients were evaluated 3 months, 1 year, 2 years, 5 years and 10 years after surgery. The main outcomes measures were refractive predictability and stability, safety, efficacy and re-treatment rate. Results: At 10 years, 20 (71%) and 23 (88%) were within ± 1.00 D after PRK and LASIK respectively. The retreatment rate was 35% and 18% respectively. No eye lost more than two lines of BSCVA in both groups. The efficacy was 0.90 for PRK and 0.95 for LASIK. Conclusions: Both PRK and LASIK were safe for moderate myopia. LASIK demonstrated slightly better efficacy, predictability, and less rate of retreatment after 10 years. The technical improvements should be taken into account when comparing these results with those obtained more recently. Photorefractive keratectomy (PRK) to correct myopia was introduced in. the late 1980s.'2 Because of severe postoperative pain and relatively slow recovery after FRK, laser in situ keratomilesis (LASIK) was introduced in the early 1990s and became the most performed refractive surgery modality in the 2000s with claimed advantages over PRK such as quick visual rehabilitation, higher predictability, minimal postoperative discomfort and absence of corneal haze." Although, studies with short-term followup reported that the risks associated with LASIK were considered to be low, postoperative flap-related complications and corneal ectasia can be sight- efficacy are the greatest concerns.410 Despite millions of procedures having been performec. there is a great lack of data about the long-terr'-comparison of PRK and LASIK." Previous studies comparing PRK and LASIK outcomes, up to 1 year after surgery, found similar or slightly better safety and efficacy outcomes for LASIK.""16 The aim of the present study is to perform a comparative analysis of the evolution of the corneal curvature and the refractive stability 10 years after myopic PRK and LASIK for moderate myopia by means of a control-matched retrospective study. METHODS Patient population A total of 4800 charts of eyes that underwent PRK or LASIK between April 1992 to December 1995 a: the Institute Oftalmologico de Alicante (Spain; were reviewed. Our database was compiled including 509 eyes of 356 patients treated with myopic PRK and 294 eyes of 178 patients treated with myopic LASIK that returned for follow-up at 3 months, 1 year, 2 years, 5 years and 10 years after the initial procedure, either spontaneously or after telephone calls (particularly at 10 years). Among this group, 34 (17 right, 17 left) PRK-treated eyes of 33 patients and 34 (15 right, 19 left) LASIK-treated eyes of 32 patients who had Br J Ophthalmol 2009:93:1313-1318. doi:10.1136/bjo.2007:131748 a preoperative spherical equivalent between —6 and 10 D were matched using the following criteria: (1) same age, (2) preoperative spherical equivalent (SE) within ±1.25 D, (3) preoperative sphere (S) wit;--;-. ±1.50 D and (4) preoperative cylinder (C) wi;r_--±2.50D. Patient demographics, refraction, mean optical zone and ablation depth at the time c.f treatment are given in table 1. The study was approved by the institutional review board (Ethical Committee of Clinical Investigation of Institute Oftalmologico de Alicante) and followed the tenets of Helsinki Declaration. Surgical procedure Inclusion criteria for surgery were: no contact lens wear 4 weeks before the surgery and stable refractive error for at least 6 months before surgery, normal peripheral retina or treated with photocoagulation when necessary, no previous ocular surgery, and no corneal diseases, glance—.; or history of ocular trauma. Exclusion criteria ::r surgery were: evidence of keratoconus or kerato-conus suspect as evidenced by corneal topography. active ocular or systemic disease likely to affec: corneal wound healing, pregnancy and nursing. 13-; Use of Anterior Segment Optical Coherence Tomography to Study Corneal Changes After Collagen Cross-linking MURIEL DOORS, NAYY1RIH G. TAHZIB, FRED A. EGGINK, TOS T. J. M. BERENDSCHOT, CARROLL A. B. WEBERS, AND RUDY M. M. A. NUIJTS • PURPOSE: To investigate the stromal demarcation line after corneal KERATOCONUS IS A BILATERAL, PROGRESSIVE COR-neal cross-linking using anterior segment optical coherence tomography (AS- disease with a multifactorial cause and a classical onset at puberty.1 It is OCT) and its influence on the short-term results of cross-linking in characterized by corneal collagen structure changes, decreased corneal patients with progressive keratoconus. rigidity, and corneal thinning, leading to a progressive corneal defor- • DESIGN: Prospective, nonrandomized study. • METHODS: Twenty-nine eyes of 29 patients with progressive mation (conical protrusion) and decreased vision.2 Early treatment options are correction of the refractive error by spectacles or contact keratoconus (n = 28) or after laser in situ keratomileusis ectasia (n =1) lenses (such as soft, rigid, or scleral lenses).3 In contact lens-intolerant were included and treated with comeal cross-linking at our institution. patients with mild to moderate keratoconus, the implantation of Measurements at 1, 3, 6, and 12 months after comeal cross-linking were: intracorneal ring segments can be considered because they lead to a refraction, best-corrected visual acuity (BCVA), tonome-try, corneal flattening effect of the cornea and can increase contact lens tolerance.4 topography, aberrometry. However, these treatment options do not interfere with the progression of Demarcation line depth was measured centrally, 2 mm temporally, and 2 AS-OCT, specular microscopy, and the disease and therefore are insufficient in cases of progressive mm nasally by two independent observers using AS-OCT and was keratoconus. In advanced cases of keratoconus (eg, with corneal scars, correlated with clinical parameters. thin, bulging corneas, or both), penetrating or lamellar keratoplasty • RESULTS: The stromal demarcation line was visible with AS-OCT at procedures are the only solution. Until now, keratoconus remains one of 1 month after surgery in 28 of 29 eyes. Pairwise comparisons between the leading indications for keratoplasty.5 For progressive, nonadvanced the two observers of the AS-OCT measurements did not show a cases, corneal collagen cross-linking has become available, leading to a statistically significant difference. After an initial steepening of maximal mechanical strengthening of the cornea and thereby achieving a keratometry values and a decrease in BCVA at 1 month after surgery stabilization of the disease. This may delay the need for keratoplasty in (both with P < .012), no significant changes were found at 3, 6, and 12 this young, nonadvanced patient group. months after surgery compared with before surgery. Refractive cylinder, Comeal cross-linking, which combines riboflavin eye-drops and topographic astigmatism, aberration values, endothelial cell density, and ultraviolet A (UVA) radiation, was first described by Spoeri and intraocular pressure remained stable during all postoperative visits. A associates in 1998.6 UVA radiation in combination with riboflavin deeper demarcation line depth was associated with a larger decrease in generates reactive oxygen species, leading to the formation of cross-links corneal thickness (r = -0.506; P = .012). between the corneal collagen fibers. The primary goal of corneal cross- • CONCLUSIONS: AS-OCT is a useful device to detect the stromal linking is to increase corneal rigidity by increasing the mechanical demarcation line after corneal cross-linking. At 3 to 12 months follow- stability of the corneal stroma. Wollensak and associates reported a 4.5- up, all clinical parameters remained stable, indicating stabilization of the times increase in biomechanical rigidity in human corneas after corneal keratoconic disease. (Am J Ophthalmol 2009;148:844-851. © 2009 by cross-linking, with a primary treatment effect in the anterior 300 (Jim of Elsevier Inc. All rights reserved.) the comeal stroma.7 In current practice, patients with progressive keratoconus or post-laser in situ keratomileusis (LASIK) ectasia may be eligible for corneal cross-linking, provided that their corneas are clear Accepted for publication Jim 28, 2009. From the Department of Ophthalmology, University Medical Center Maastricht, Maastricht, The Netherlands. Inquiries to Rudy M. M. A. Nuijts, Department of Ophthalmology, University Medical Center Maastricht, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands; e-mail: [email protected] 844 and not too thin.8"10 In 2003, Wollensak and associates reported the first clinical shortterm results of corneal cross-linking in patients with progressive keratoconus.9 They found that the progressive nature of keratoconus was at least stopped in all ' 2.009 BY ELSEVIER INC. ALL RIGHTS RESERVED. Endothelial Growth Factor as a Thickening Following Cataract "-' With Diabetes Mellitus Aqueous ¥. Predictor of Surgery & 1»K3it3»LA5 TnSKHAM, LAUREN PAYNTER, PETE GEISEN, CATt KOCH, AND KENNETH L. COHEN M. ELLZH CYSTOID MACULAR EDEMA (CME) AND EXACER-bated diabetic PURPOSE: To aqueous vascular ;-- 1 /•••TflirffcilBBIl^1'1111'**''^ insulin-like 11 1 grow-th -i---' 1 " •wE.'-sh. measured with ;~; . -BeaBigim; following phacc=~- 1 - Lair1 ilEli • DESIGN; Cohc" •-.. • METHODS: A :-_ - macular edema (DME) can adversely affect visual outcomes following cataract ^rgery in patients with diabetes mellitus (DM).1"5 With :e;hnical improvements in cataract surgery, better glyce-mic control in patients with diabetes, and preoperative la5er treatment for clinically significant macular edema (CSME), long-lasting macular edema (ME) following IOL in 1 eye bv i:1^11; -ii.cpai.a: ! •1 • 111 li lliii 11 ~A Carolina conser-'er - cataract surgery is reported less often now than in the past, but the .-gis'iti1 - problem of postoperative ME still exists.3'6 A 30% increase in the center . Four patients point thickness as measured by optical coherence tomography (OCT) was <—:, •aHWW^^'ws OCT central '•_-"- _ , T •sr.si'.-rr-'s'—^'a. and aqueous ar-i : . '•'•^." (CSME) receive correlations we-e : reported in 22% of patients with diabetes at 1 month postcataract mean CSF or & ; CSF (>11% c: T-months extraction. More than half had resolution at 3 months in this study. postope-;: However, delay in treatment of macular edema has been shown to reduce 1 visual improvement following cataract extraction in some patients.8'9 • RESULTS: Th^-; cases of CSME -: "gBiiir Tm iir r ciaa in patients with : r increased with :~ .:• preoperative C''1-,~Z and the greatest OK erative correlatic-^? more severe rer^:---3« absent (r = 0.41-: ? = VEGF and C?},^ - = postoperative, a;-:1 . n'anii" Twainawith >11% chanCSME status '- = associations ex:—• CONCLUSION' - . _ia—, •» tively associate J -- . in diabetic pat^r: Therefore, preoperative measurements that identify patients at risk for J'y ••«i««»——r:i;iaiiff Accounting for pre.:B-ther study is in^^i-sn*-1 895-901. © 2C03 ^ E ME after cataract surgery may be beneficial to initiate treatment early and reduce vision loss from ME. Vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) have been implicated in the pathogenesis of ME and diabetic retinopathy (DR). VEGF is a vasopermeability factor10 and has been associated with DME.11 Intravitreous injections of agents that neutralize the bioactivity of VEGF have stabilized or improved visual acuity (VA) and reduced central subfield thickness (CSF) as measured by OCT in phakic patients with DME12 and have had mixed reports in nondiabetic pseudophakic patients with CME.13'14 Another study reported that elevated aqueous levels of VEGF, IL-6, and protein were associated with exacerbated fluorescein leakage in the maculas of diabetic patients 6 months following cataract surgery. A recent report showed that 8 patients with diabetes who had had intravitreous bevacizumab (Avastin; Accepted for pu't-":: From the Dep.— K.L.C.) and BK--- Chapel Hill, Nc^ ^ Inquiries to M. ^._ JI North Carolina. 27599; e-me:: - Genentech Inc, South San Francisco, California, USA) for CSME prior to cataract surgery had reduced aqueous VEGF levels at the time of surgery 2 months later, but only a transient reduction in CSF.16 The efficacy of : . NC -mi—fcsaEBl?" -•:•»- : B C-'T •"T^-"^, ALL RIGHTS RESERVED. M02-9394/09/S3^ :•: Fsr- doi:10.1016/j.ajo._:C- --.. T3L, ..3BCMEa- anti-VEGF treatment for prevention or treatment of postoperative CME or exacerbation of CSME from cataract surgery in patients with diabetes remains indeterminate and may require further study. 895 A simple and evolutional approach proven to recanalise the nasolacrimai duct obstruction D Chen,1 J Ge,2 L Wang,2 Q Gao,2 P Ma,2 N Li,2 D-Q Li,3 Z Wang2 10 See Editorial, p 1416 ABSTRACT Aini: To evaluate a new created in 1994. Since then, this approach has been widely adopted by many in China for its simplicity, ' Department of ENT, First approach of recanalisation of safety, efficacy andophthalmologists minimal invasion.""15 In the present study, Affiliated Hospital, Sun Yatnasolacrimai duct obstruction (RC- we report the long-term follow-up results of RC-NLDO in the sen University, Guangzhou, PR China; 2 State Key NLDO) in the treatment of the clinical treatment for 506 cases of NLDO and chronic Laboratory of nasolacrimai duct obstruction (NLDO) dacryocystitis, as well as the histopathological evidence from Ophthalmology, Zhongshan animal experiments. The relative indication, contraindication, and chronic dacryocystitis. surgical technique, postoperative care, complications, Ophthalmic Center, Sun Yat-sen University, Methods: 583 patients with 641 eyes advantages and disadvantages of the RC-NLDO are discussed. Guangzhou, PR China; suffering from NLDO and chronic Sullen Eye Institute, MATERIALS AND dacryocystitis were enrolled in this Department of Ophthalmology, Baylor METHODS Patients study. The RC-NLDO was performed College of Medicine, This study adhered to the tenets of the Declaration of Helsinki in 506 eyes, with 135 eyes undergoing Houston, Texas, USA and was approved by the Institutional Review Board external dacryocystorhinostomy (EX(IEJB)/Ethics Committee of Zhongshan Ophthalmic Center, Correspondence to: DCR) as controls. Patient follow-up for Sun Yat-sen University. All cases were chosen from Dr Z Wang, Zhongshan Ophthalmic Center, Sun 54 months was evaluated by symptoms, outpatients who were diagnosed as having NLDO and/or Yat-sen University, No 54 S dacryocystitis. Every patient underwent preoperatively dye disappearance test, lacrimal chronic Xianlie Road, Guangzhou comprehensive ophthalmic and intranasal examination. irrigation and digital subtraction Dacryocystogram or digital subtraction dacryocystogram was 510060, PR China; [email protected] dacryocystogram. The RC-NLDO was performed in some cases. also performed in 12 rhesus monkeys A total of 641 eyes of 583 consecutive patients were Accepted 20 February 2009 from July 2003 to June 2006 with their signed for histopathological examination. recruited Published Online First 4 informed consent forms, including 135 eyes of 126 patients May 2009 Results: The clinical success rates were undergoing the EX-DCR and 506 eyes of 457 patients 93.1% in 506 cases of RC-NLDO and undergoing the RC-NLDO. There were no statistical 91.11% in 135 cases of EX-DCR, The differences in patient demographics between these two groups. male-to-female ratio was approximately 1:3, and the success rates for second surgery were The average age was 50 years. The duration of symptoms ranged achieved in 85.19% on RC-NLDO and from 6 months to 26 years (mean 5.1 years) in the RC-NLDO 40.0% on EX-DCR. No major intra- or group and from 6 months to 17 years (mean 4.7 years) in the postoperative complications were EX-DCR group. Nasolacrimai duct obstruction (NLDO) and chronic dacryocystitis are common ophthalmic diseases. The external dacryocystorhinostomy (EX-DCR) has been the most effective and standard surgery in treating these conditions since 1904 when it was reported by Toti.' However, EX-DCR is an invasive, relatively complex and time-consuming procedure that causes a facial cutaneous scar. Many patients prefer to suffer tearing rather than undergo this surgery.2 3 The improvement on DCR has been made recently, such as the endonasal DCR and endocanalicular laser DCR. These approaches were promising but still necessitate bone removal and require costly equipment. These surgical procedures were reported to have less effective results than EX-DCR and involve a marked learning curve.^9 The approach of the EX-DCR and these new procedures is to create a bypass draining system, rather than to restore the obstructed nasolacrimai duct. Recanalisation of nasolacrimai duct obstruction (RC-NLDO) was an evolutionally developed surgical approach for treating these conditions to restore the native nasolacrimai duct, using a simple instrument, the lacrimal canaliser, which we This paper is freely available online under the BMJ Journals unlocked scheme, see http:// bjo.bmj.com/site/abouV unlocked.xhtml instrument used for RC-NLDO The instrument used for recanalisation of nasolacrimai duct obstruction was the lacrimal canaliser consisting of a console and its accessories (fig 1). The console can discharge a power current (50-150 W) with 500kHz frequency. The high-frequent lacrimal (HFL) probe is made of copper-silver alloy 1.2 mm in diameter and 140 mm in length. Its tip is 2.0 mm long, smooth, blunt and naked (without an insulating coat on the surface), features allowing it to cauterise blocked tissue in a nasolacrimai duct. Surgicai procedures EX-DCR was performed under local anaesthesia in a standardised fashion.9 The RC-NLDO was 1438 Ctiiteal SsBr Macular thickness decreases with age in normal eyes: a on the macuSar thickness map protocol in the Stratus OCT U Eriksson, A Aim Department of Neuroscience, Ophthalmology, University Hospital, Uppsala, Sweden Correspondence to: Dr U Eriksson, Akademiska sjukhuset, Ogonmottagningen, ing 70, University Hospital, S-701 85 Uppsala, Sweden; urban.eriksson@akademisk a.se Accepted 11 June 2008 Published Online First 19 November 2008 ABSTRACT Background/aim: Retinal and retinal nerve fibre layer (RNFL) thinning with age have been described in histological studies. In vivo techniques like optical coherence tomography (OCT) have shown thinning of optic nerve RNFL and the retina in specific areas. One would expect thinning of the total macula, but so far, no correlation with the quantitative OCT macular map tool and age has been found. Methods: Sixty-seven healthy individuals underwent three repeated scans in both eyes with the macular thickness map protocol in the Stratus OCT. That protocol divides the macula area into nine ETDRS fields. The RNFL was measured in one specific location close to the optic disc. Correlations between retinal, RNFL thickness, macular volume and age were determined. Results: We found a statistically significant negative relationship between retinal thickness and age for all ETDRS areas, total macular volume and RNFL thickness. Retina] thickness decreased by 0.260.46 urn, macula volume 0.01 mm3 and RNFL 0.09 u.m per year. Conclusion: Retinal thickness within the area covered by the macular map significantly decreases with age. In the area examined in the papillomacular bundle, 20% of the retinal thinning is due to the RNFL, and 80% is due to thinning of other layers of the retina. Histological studies of the human retina and optic nerve have shown a decreased density of photo-receptors, ganglion cells, retinal pigmentepithelium and optic nerve fibres with age.*"3 With optical coherence tomography (OCT), both qualitative and quantitative measurements of the retina can be made.^7 A macular mapping technique that has shown a good reproducibility is implemented into the OCT 2000 and OCT3 scanners, which are in clinical use today.8"13 Observations based on single scan measurements have shown a decrease in retinal and RNFL thickness with age. In a pilot study, Schuman et al reported that the peripapillary retinal nerve fibre layer (RNFL) decreases with age using OCT I.14 Poinoosawmy and coworkers also demonstrated a progressive reduction in the nerve fibre layer thickness with age using scanning laser polarime-try (GDx).15 In an OCT study by Alamouti and Funk, both retinal and RNFL thickness decreased slightly with age.16 Finally, Kanai and coworkers also found that retinal thickness decreases with age.17 None of these investigators, however, used the OCT mapping technique. Based on the findings in postmortem and in vivo studies, one would expect a slight thinning of the total retina. Surprisingly, studies on normal retinal thickness with the mapping protocol have so far not shown any significant correlation between retinal thickness and age.8"" Therefore, we wanted to examine the relation between retinal thickness and age with the macular map technique. SUBJECTS The study was conducted in accordance with the guidelines of the Declaration of Helsinki, and the protocol was approved by the ethics committee of Uppsala University. A total of 134 eyes from 67 healthy Caucasian subjects (43 women (64%) and 24 men (36%), median age 34.4 years (range 12-74)), recruited among the staff and their families at the department of ophthalmology, University Hospital, Uppsala, were included. All subjects underwent three measurements with the map protocol in both eyes. Before inclusion, a thorough medical history was obtained, and all subjects underwent a routine ophthalmological examination including visual acuity, slit-lamp examination and dilated fundus examination with the 60-dioptre lens in the slit lamp. Subjects with a history of any ophthalmological condition or positive findings on a routine eye examination were excluded. A visual acuity below 1.0 (20/20) and a refractive error of more than 6 dioptres spherical and/or more than 3 dioptres cylindrical were exclusion criteria. METHODS The pupils were dilated with 0.5% tropicamide, and all subjects underwent a dilated slit-lamp examination. The latest commercially available OCT model, Stratus OCT 3 (Carl Zeiss Meditec. Dublin, California) with software 4.0.1, was used. In Stratus OCT, there are three different map protocols. The macular thickness map protocol was used in this study. OCT is a non-invasive, non-contact technique by which to obtain high-resolution images from the anterior and posterior segments of the eye.4"6 Utilising the principles of ultrasound, OCT measures backscattered low-coherent light from intraocular structures as an A-scan. Cross-sectional tomographic images (B-scans) are constructed from repetitive axial Ascans while the probe beam scans across the retina. The retinal thickness is defined as Br J Ophthalmol 2009;93:1448-1452. doi:10.1136/bjo.2007.131094 1448 EDITOR'S CHOICE Intravitreal injection of pegaptanib sodium for proliferative diabetic retinopathy V H Gonzalez, G P Giuliari. R M Banda, D A Guel Valley Retina Institute, PA, McAllen, Texas, USA Correspondence to: Or V H Gonzalez, Valley Retina Institute, PA, 1309 East Ridge Road, Suite 1, McAllen, TX 78503, USA; [email protected] Received 5 December 2008 Published Online First 18 August 2009 ABSTRACT Background: To compare the efficacy of intravitreal pegaptanib (IVP) with panretinal laser photocoagulation (PRP) in the treatment of active proliferative diabetic retinopathy (PDR). Methods: A prospective, randomised, controlled, open-label, exploratory study. Twenty subjects with active PDR were randomly assigned at a 1:1 ratio to receive treatment in one eye either with IVP (0.3 mg) every 6 weeks for 30 weeks or with PRP laser. Efficacy endpoints included regression of retinal neovascularisation (IW), changes from baseline in best-corrected visual acuity (BCVA) and foveal thickness. Safety outcomes included observed and reported adverse events. Results: In 90% of randomised eyes to IVP, retinal IW showed regression by week 3. By week 12, all IVP eyes were completely regressed and maintained through week 36. In the PRP-treated group, at week 36, two eyes demonstrated complete regression, two showed partial regression, and four showed persistent active PDR. The mean change in BCVA at 36 weeks was +5.8 letters in pegaptanibtreated eyes and -6.0 letters in PRP-treated eyes. Only mild to moderate transient ocular adverse events were reported with pegaptanib. Conclusions: IVP produces short-term marked and rapid regression of diabetic retinal IW. Regression of NV was maintained throughout the study and at the final visit. Diabetic retinopathy (DR) is a major cause of blindness in the Western world.'2 Research into the aetiology of ocular neovascular diseases such as DR has identified a pivotal role for vascular endothelial growth factor (VECE) in promoting both angiogenesis and increased vascular permeability.3 4 Intravitreal injection of VECP induces many of the pathological changes characteristic of DR, including intraretinal and preretinal neovascularisation, microaneurysm formation, intraretinal haemorrhage, macular oedema and areas of capillary non-perfusion with endothelial cell hyperpla-sia.5 Elevated intraocular levels of VEGF have been reported in patients with DR. Moreover, this elevation is more pronounced in PDR than in non-proliferative diabetic retinopathy (NPDR)/ 7 The Isoform.165 of VECF-A (VECFi®) is particularly potent in promoting ocular neovascularisation and breakdown of the blood-retinal barrier (BRB) through a leucocyte-dependent mechanism.8 " Pegaptanib sodium is a selective anti-VECF aptamer that binds to VECE^.10 Preclinical studies demonstrated that intravitreal injections of pegaptanib (IVP) can inhibit pathological ocular neovascularisation while leaving physiological vascularisation unimpaired.8 In a recent Phase II study of pegaptanib for the treatment of diabet:: macular oedema (DME), findings suggested ths-IVP may be capable of halting and even reversing pathological retinal neovascularisation (NV)." " | We hypothesised that in patients with active ' PDR, IVP would cause marked reduction ir vitreous levels of VECFi® with regression or pathological NV, thereby hindering the progressior. of PDR. In this report we present the final results from our pilot, study to test this hypothesis. METHODS Study design This study was a randomised, prospective, open-label direct comparison of pegaptanib alone to PRP alone in patients with PDR. It was approved by the Sterling Institutional Review Board, and conducted in conformity to the principles of the Declaration of Helsinki. Subject selection Eligible subjects had active FDR, in one or both eyes, with at least one of the following high-risk characteristics as defined by the Diabetic Retinopathy Study (DRS): (1) new vessels within one disc diameter of the optic nerve head that are larger than a third of the disc area and/or (2) vitreous or preretinal haemorrhage associated with either less extensive new vessels at the optic disc, or with new vessels elsewhere half the disc area or larger.13 In addition, at the screening visit, the best-corrected visual acuity (BCVA; measured by the Early Treatment Diabetic Retinopathy Study (ETDRS) chart) was s'24 letters (approximately 20/320) and <85 letters (approximately 20/20). Eyes with mild preretinal haemorrhage or vitreous haemorrhage (VH) that did not interfere with visualisation of the macula and optic disc were eligible for inclusion. Subjects could participate in the study only if, in the opinion of the evaluating physician, PRP could be safely withheld for 4 weeks. Exclusion criteria included the following: haemorrhage or media opacity obscuring visualisation of the macula and optic nerve; significant epiretinal membranes (ERM) involving the macula; proliferative diabetic membranes along the major retinal arcades sufficiently extensive to cause either significant vitreomacular traction or significant impairment in BCVA; any tractional retinal detachment; severe ischaemia involving the foveal avascular zone; neovascular glaucoma; study eye treated with intravitreal steroid injections within 6 months prior to baseline and/or PRP treatment within 90 days of baseline. tWmlcal science] Predicting visual success in macular hole surgery B Gupta; D A H Laidlaw,1 T H Williamson,1 S P Shah,2 R Wong,1 S Wren1 predicting restoration of good visual acuity (VA) (better than ABSTRACT ' Department of 20/40; 6/12 UK Snellen) and to present these data in a Aim: Data on the outcome of surgery facilitate Ophthalmology, St clinically usable format for use in preoperative counselling. Thomas's Hospital, London, informed preoperative patient counselling. Most 2 studies on the outcome of surgery for idiopathic UK; International Centre As surgical techniques are known to differ widely,7"9 in for Eye Health, Clinical full thickness macular hole surgery have building the cohort we only included patients that had the Research Unit, London concentrated on rates of anatomical closure. The same surgical technique and postoperative instructions, so that School of Hygiene and aim of this study was to identify factors predicting this study had one of the largest cohorts of patients Tropical Medicine, London, visual success (better than 20/40; 6/12 Snellen) undergoing standardised macular hole surgery. UK following macular hole surgery. Methods: A retrospective study of 133 patients undergoing Correspondence to: standardised macular hole surgery with at least 3 METHODS Mr D A H Laidlaw, months of postoperative follow-up. All patients A retrospective case note review of all phakic patients Department of underwent preoperative measurement of the undergoing surgery for IFTMH under one consultant-led Ophthalmology, St maximum macular hole diameter using optical surgical team from March 2004 until October 2007 was Thomas's Hospital, coherence tomography. Results: Multivariable performed. Only the first operation on the first operated eye of Lambeth Palace Road, regression analysis identified that age, each patient was included in the analysis. Exclusion criteria London SE1 7EH, UK; preoperative visual acuity and macular hole size included macular holes in association with trauma, any Alistair. were significant predictors of visual success. The previous intraocular surgery and a history of other [email protected] resulting model correctly classified the visual limiting eye conditions such as age-related macular outcome of 80% of cases. Predicted rates of degeneration, glaucoma and amblyopia. Accepted 7 May 2009 visual success varied from 93% in patients <60 Published Online First Data collected included: age, sex, laterality, duration of years old with visual acuity better than 6/24 and 26 July 2009 visual symptoms, preoperative VA, preoperative maximum a hole diameter of <350 u.m, to 2% in patients linear dimension (MLD), those >79 years old with visual acuity of 6/60 or worse and hole diameter of >500 urn. Conclusion: The results provide a simple and clinically useful model to employ when counselling patients on macular hole surgery. Data on the outcome of surgery facilitate informed grade of operating surgeon, intra- and postopera-1 tive complications, postoperative anatomical do- j sure and VA at 3 months (table 1). ! Preoperative MLD of the IFTMH was measured : using optical coherence tomography (OCT) (Stratus OCT, Zeiss (Carl Zeiss Meditec, Inc., Dublin, California, USA) and Topcon 3D OCT-1000 (Topcon Medical Systems, Paramus, New Jersey, USA)) and was defined as the greatest linear distance along the smallest hole aperture (fig 1). All cases underwent phacoemulsification and intraocular lens implantation followed by 20-gauge three-port pars plana vitrectomy with induction of a posterior vitreous detachment when not already present. Indocyanine green (ICC)-assisted internal limiting membrane peeling was performed in all cases, using 0.5 ml of 0.5 mg/ml (0.05%) ICG and minimal retinal exposure time followed by fluid to air to 16% CgFg gas exchange. All patients were instructed to maintain an upright postoperative posture during the day and to strictly avoid sleeping in a supine position. Follow-up was performed at day 1, 2 weeks and 3 months. Anatomical closure was determined at 3 months after surgery using indirect slit lamp biomicro-scopy. Statistical analysis Snellen acuities were converted to logMAR units for analysis. LogMAR values of 2.0 and 3.0 were used for vision of counting finger and hand movement, respectively. Distribution analysis revealed postoperative vision and MLD to be non-normally distributed. In order to make prediction probabilities easier for application in a clinical setting a binary outcome variable "visual success" was defined, consistent with previous literature,10 as postoperative VA of <0.3 logMAR (better than 6/12) at 3 months. MLD was categorised into quartiles (<350, s'350 to <400, 3=400 to <500, 3=500 urn), age into decades, and preoperative VA as ss0.3 to <0.6, ss0.6 to <0.9 and &0.9 logMAR. Logistic regression analysis was used to determine which explanatory variables were to be included in the predictor for visual success. The multivariable model was built using a forward manual stepwise method by adding the most significant variable first. The significance level for removal from the model was p=0.1. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived from this model. All p values were two-sided. Prediction models using logistic regression were evaluated by establishing a cut-off point; predicted probabilities below the cut-off point were treated as predictors of no event and predictions at or above the cut-off point were considered to be predictors of the event." A cutoff point of 0.50 was usually chosen. Using the 0.5 prediction cut-off points, we fir J Ophthalmol 2009:93:1488-1491. doi:10.1136/bjo.2008.153189 ^^.^.^^.^^..^.......MsVSKU Cataract surgery and primary intraocuiar lens implantation in children <2 years old in the UK and Ireland: finding of national surveys A L Solebo,1'2 I Russell-Eggitt,2'3 K K Nischal,2-3 A T Moore,™ P Cumberland,1-2 J S Rani,1'2'3'4'5 on behalf of the British Isles Congenital Cataract Interest Group ' MRC Centre of Epidemiology for Child Health, UCL Institute of Child Health, London, UK: 2 Ulverscmft Vision Research Group, UGL Institute of Child Health, London, UK; clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK; ''Moorfields Eye Hospital, 5 London, UK: UCL Institute of Ophthalmology, London, UK ABSTRACT Background: Current patterns of practice relating to primary intraocular lens (IOL) implantation in children <2 years old in the UK and Ireland are investigated. Methods: National postal questionnaire surveys of consultant ophthalmologists in the UK and Ireland. Results: 76% of 928 surveyed ophthalmologists replied. 47 (7%) of the respondents operated on children aged < 2 with cataract. 41 (87%) of respondents performed primary IOL implantation, but 25% would not implant an IOL in a child under 1 year old. 88% of surgeons used limbal wounds, 80% manual capsulotomies, 98% posterior capsulotomies and 100% hydrophobic acrylic lenses. The SRK/T formula was most commonly used (70%). Exclusion criteria for primary IOL torrespondence to: implantation varied considerably and included Or J Rahi, MRC Centre of microphthalmos (64% of respondents), anterior Epidemiology for Child and posterior segment anomalies (53%, 58%), and Health, UCL Institute of glaucoma (19%). Discussion: Primary IOL Child Health, 30 Guilford Street, London WG1N 1EH, implantation in children <2 has been widely adopted in the UK and Ireland. There is UK; [email protected] concordance of practice with regards to surgical technique and choice of IOL model. However, Accepted 7 May 2009 there is some variation in eligibility criteria for Published Online First primary lOLs: this may reflect a lack of consensus 16 June 2009 on which children are most likely to benefit. Thus, there is a need for systematic studies of the outcomes of primary IOL implantation in younger children. Primary intraocular (IOL) implantation has become accepted practice for older children with cataract.'2 While primary IOL implantation is being increasingly undertaken in children in the first 2 years of life,3 4 the long-term benefits and the factors associated with positive and negative outcomes are unclear.'2 5-9 The British Isles Congenital Cataract Interest Croup (BCCIG), a research network comprising British and Irish ophthalmic consultants, was established in 1995 in order to study the incidence, detection, causes, management and outcomes of congenital and infantile cataract.10-14 A national epidemiological study to investigate outcomes following primary IOL implantation in children < 2 years old with congenital and infantile cataract is now being undertaken through the BCCIG. As a foundation for this research, we have investigated the surgical management of .cataract in younger children in the UK and Ireland, with a focus on primary IOL implantation. the Royal College of Ophthalmologists and Irish consultant ophthalmologists with a known interest in congenital cataract, were contacted using postal questionnaires accompanied by hand-addressed cover letters and postage-paid reply envelopes. Members of the BCCIG who did not respond to the mailing were sent reminders. We sought to discover the number of children < 2 years old with congenital or infantile cataract managed over the previous year, the number undergoing surgery with and without primary IOL implantation and the details of surgical management. Respondents were asked to estimate the number of children managed over the preceding year. Exclusion criteria for primary implantation in children <2 were requested, as were preferred IOL model and IOL power calculation formulae together with details of surgical technique including lens aspiration and vitrectomy approaches and capsulotomy practices. The postoperative measurement of axial length was also investigated. Statistical analysis Free text answers on exclusion criteria were coded. A descriptive analysis of the responses was undertaken. RESULTS Thirty-two of the 960 distributed questionnaires were returned as undeliverable. Of the remaining 928 contacted consultants, 709 (76%) replied to the survey. Replies were received between October 2008 and January 2009. Of the 709 respondents, 47 (7%) stated that they operated on children <2 years old, estimating that over the preceding year they had operated on a total of 301 children. Six (13%) of the 47 surgeons did not perform primary IOL implantation in any child <2. The 41 surgeons who did perform primary IOL implantation estimated that in the preceding year they had operated on 268 children (116 with unilateral, 152 with bilateral cataract), undertaking primary IOL implantation in 65% (table 1). Exclusion criteria Exclusion criteria for primary IOL implantation in children <2 were provided by 36 of the 41 respondents. Six (17%) surgeons did not mention any ocular anomaly among their stated exclusion criteria. Twenty-three (64%) described specific anomalies which would prevent them from METHODS In October 2008, 960 consultants comprising all members of the BCCIG, all consultant members of Br 5 J Ophthalmol 2009:93:1495-1498. doi:10.1136/bjo.2009.160069 149 Comparison of long-term surgica/ success of Ahmed Valve implant versus trabecu/ectomy in openangle glaucoma D H Iran/ C Souza,1-2 M J Ang,' J Loman,1 S K Law/ A L Coleman,1 J Caprioli1 ' Glaucoma Division, Jules Stein Eve Institute, David Geffen S^'^v of Medicine, University of ;s -omia Los Angeles, Los Angeles, USA; 2 Ophthalmology Dspartment, Federal University v Sao Paulo, Sao Paulo, Brazil ABSTRACT Aim: To compare the long-term intraocular pressure (IOP) outcomes of Ahmed Glaucoma Valve (AGV) implantation to trabeculectomy with mitomycin C (MMC) in open-angle glaucoma fOAGj. Methods: 78 OAG patients who underwent AGV implantation were matched with respect to age, preoperative surgery, preoperative IOP and preoperative medicines to 88 OAG patients who underwent trabecu;-:"3saondence to: lectomy with MMC with a minimum of 3 years' follow~-.~ - CaB'ioli, Glaucoma up. The cumulative probability of success between the Division, . - 55 S-sn Eye two groups with different criteria was analysed: (1) an Institute, 100 S:;' ^azs, Los IOP<21 mm Hg and a reduction of IOP5s'15% from Angeles, ^ 9:Ca5, USA; baseline; and (2) an IOP < 18 mm Hg and a reduction of :2:-: ^'ss'.ucla.edu ,^£C2a a Fsbruary 2009 IOPss20% from baseline. No loss of light perception, no additional glaucoma surgery and no hypotony were also Ptasres Offline Frst) required. July 2009 Results: The 5-year cumulative probability of success was not statistically significant between eyes that had an AGV or trabeculectomy with MMC when success was defined as criteria A (p == 0.094). However, when success was defined according to criteria B, eyes undergoing trabeculectomy with MMC had a higher rate of success (p = 0.024). Conclusions: Trabeculectomy with MMC has a significantly higher 5-year cumulative probability of success compared with AGV implants when greater reduction IOP is necessary. It is estimated that by 2010, 60 million people worldwide will suffer from some type of glaucoma. Open-angle glaucoma (OAG) accounts for 74% of these cases.' In OAG, the intraocular pressure (IOF) is frequently controlled with medications. However, when medications and lasers fail to control IOP, surgical management is necessary. Two surgical treatments with the longest success records are trabeculectomy with mitomycin C (MMC) and glaucoma drainage devices (GDD). Prior studies have reported 40-90% success rate with trabeculectomy in OAC." However, the majority of the studies with GDD include patients with neovascular, uveitic, developmental and mixed glaucoma (referred to as refractory, intractable or complicated glaucoma).7'17 furthermore, there are fewer studies comparing the two surgical modalities, and only one of them is in patients with OAC. Currently, there is an ongoing prospective study comparing the 350 mm2 Baerveldt glaucoma implant to trabeculectomy with MMC in patients with OAG and chronic angle-closure •glaucoma (CACG).18 The treatment outcomes in the Tube Versus Trabeculectomy study reported a higher 1-year success rate in patients with the Baerveldt compared with trabeculectomy with MMC. One study comparing Ahmed Glaucoma Valve (AGV) implant with trabeculectomy with MMC in patients with primary OAG, secondary OAG and primary angle-closure glaucoma (PACG) reported no difference between the two groups with follow-up times of 6-13 months.8 Another study, by the same group, also reported no difference between the two groups at 31 months in patients with primary OAG and FACG.20 There is only one prior study comparing cataract extraction combined with Molteno implant or trabeculectomy in patients with OAG.21 Molteno and coauthors also reported no difference between the two groups at 8 years. As far as we are aware, there is currently no data comparing ACV with trabeculectomy with MMC in patients with OAG beyond 3 years. The purpose for this study is to compare the long-term surgical success of ACV implantation with trabeculectomy in OAG. PATIENTS AND METHODS This is a retrospective case-controlled study of patients with OAC, which includes primary open-angle (POAG), pseudoexfoliation glaucoma '(PXPG) and pigmentary dispersion glaucoma (PDG), who underwent ACV implantation (New World Medical, Rancho Cucamonga, California) or trabeculectomy with MMC at the Jules Stein Eye Institute, University of California, Los Angeles with a minimum of 3 years' follow-up time. The surgery was performed by three experienced surgeons (JC, ALC or SKL) from 1994 to 2004. One hundred and eighty-eight eyes from 166 patients followed at the Jules Stein Eye Institute from 1994 to 2007 were identified. OAG eyes that had ACV implantation were matched with OAC eyes who had trabeculectomy with MMC with respect to age, preoperative IOF, preoperative medicines and prior surgeries (no prior surgery, cataract surgery and one or more glaucoma surgeries). The study protocol was approved by the Human Subject Protection Committee at the University of California, Los Angeles, and all study procedures adhered to the recommendations of the Declaration of Helsinki. Data collection Preoperative data collected were age at the time of the surgery, gender, race, self-reported history of hypertension and diabetes, best-corrected visual acuity (BCVA), mean intraocular pressure (IOP) Br J Ophthalmol 2009;93:1504-1509. doi; 10.1136/bJ0.2008.150870 Turnover rate of tear-film lipid layer determined by fluorophotometry 1 Division for Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan; 2 Department of Ophthalmology, Keio University School of Medicine, Tokyo. Japan Correspondence to: Dr M Yamada, Division for Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo 1528902, Japan; yamadamasakazu@kankak uki. go-IP Accepted 1 July 2009 Published Online First 18 August 2009 H Mochizuki,1 M Ya.mada,1 S Hatou,1'2 K Tsubota2 16 Of these, ABSTRACT of evaporation from the ocular surface." observation of lipid layer characteristics by interferometric Aim: This study was performed to methods has been well established."'17 In various pathological conditions, such as meibomian gland dysfunction, the independently assess of the lipid layer can change. Lipid layer thickness, the turnover rates of aqueous and lipid appearance measured by interferometry, has been reported to correlate layers of the tear with tear-film evaporation, tear-tilm breakup time, and clinical 3 la We have previously reported that the film. symptoms. concentration of lipocalin in tears from patients with Methods: Two fluorescent dyes, meibomian gland dysfunction was significantly lower than in fluorescein sodium and 5- normal controls.19 Thus, lipids in tears, both in the lipid layer dodecanoylaminofluorescein (DAF), and in the aqueous layer held by lipocalin, are important when the pathophysiology of evaporative dry eye, such which is a free-fatty-acid conjugate of considering as meibomian gland dysfunction. Until now, however, there fluorescein, were applied to the right has been no information about the flow rate of tear-film lipid eye of 12 healthy volunteers. layer. Fluorescent intensity of the precorneal Aqueous tear flow is determined by several aspects of tear including tear production, tear volume, tear tear film was measured at the central dynamics evaporation and tear outflow.20 Tear flow can be assessed by cornea every minute for 10 min for introducing a dye or radioactive substance into the fluorescein sodium, and every 5 min for conjunctival sac and measuring the decay in concentration 21 50 min for DAF. The turnover rate was over a certain period. Since the report of Mishima et al, measurement using fluorescein sodium as a calculated by plotting fluorescent fluorophotometric tracer has been the gold standard to quantify tear flow.16 20 The intensity against time in a semilog plot elimination rate of fluorescein sodium essentially represents and expressed as %/min. Results: the bulk aqueous flow because the dye is hydrophilic; Turnover rates of fluorescein sodium however, the turnover of a certain tear component may not The precorneal tear film has traditionally been described as consisting of an outer lipid layer, a middle aqueous layer and an inner mucus layer. Although this remains valid, some modifications have been proposed.''3 In the current model of the tear film, the aqueous-mucin layer is covered by two thin layers of lipids. Polar lipids such as phospholipids lie adjacent to the aqueous-mucin layer, and non-polar lipids such as cholesterol and wax ester are present at the tear-air interface. In addition, tears contain proteins that possess lipid-binding properties, such as tear lipocalin.4-" Although lipids in tears are primarily located in the tear-film lipid layer, some lipids are presumably bound by lipocalin in the aqueous layer. Tear lipocalin is thought to have an important role in stabilising the tear-film lipid layer by transferring lipids to it from the aqueous layer.""6 Despite comprising a very small proportion of the overall tear-film thickness, the lipid layer is important for retarding evaporation and maintaining tear-film stability.2 3 Where the lipid layer is absent or where the integrity of the lipid layer is compromised, the evaporation rate of tears increases, accompanied by tear-film instability.7 8 To assess the lipid layer of tears, several techniques have been developed, including observation of lipid layer characteristics by interferometric methods,sl-n quantitative measurement of meibomian lipid on the lid margin by meibometry12 13 and measurement parallel the bulk aqueous flow. For example, we recently reported differences between the bulk aqueous flow of hyaluronic acid and the turnover of hyaluronic acid, suggesting that hyaluronic acid remains on the ocular surface independent of the bulk aqueous flow.22 Accordingly, we hypothesised that the flow rate of the tear lipid layer might be different from that of aqueous tear layer. In this study, we tested this hypothesis using fluorescein sodium and a free-fatty-acid conjugate of fluorescein. Fluorescein was used to assess the aqueous flow, and the conjugated dye was used as a tracer to determine the How rate of the tear lipid layer. METHODS Fluorescent dye and fluorophotometer 5-Dodecanoylaminofluorescein (DAF; Molecular Probes, Eugene, Oregon) is a lipophilic and water-insoluble free-tattyacid conjugate of fluorescein. This dye has the longestwavelength absorption maximum at 495 nm, and an emission spectrum that peaks at 518 nm. A DAF emulsion (50 mg/ml) was prepared in sterile 0.067 M phosphate-buffered saline (PBS), pH 7.4, with 1% Tween 80 This paper is freely available online under the BMJ Journals unlocked scheme, see http;// bjo.bmj.com/site/about/ unlocked.xhtrril « Br J Ophthalmol 2009:93:1535-1538. doi:10.1136/bjo.2008.156828 1535 Comparison of Outcomes of Lamellar Keratoplasty ano Penetrating Keratoplasty in Keratoconus DAPHNE C. Y. HAN, JODHB1R S. MEHTA, YONG M1NG POR, HLA MYINT HTOON, AND DONALD T. H. TAN • PURPOSE: To compare outcomes after penetrating ker-atoplasty (PK) PENETRATING KERATOPLASTY (PK), THE FULL-THIC-ness and two techniques of deep anterior lamellar keratoplasty (DALK) in replacement of a diseased cornea with -r_ allograft donor cornea, has patients with keratoco- been a well-accepte-surgical treatment for keratoconus over the past few nus. decades.1"4 However, it can be complicated by allograr endothelial • DESIGN: Retrospective cohort study. • METHODS: One hundred and twenty-five corneal transplantations subsequent risk of graft failure Deep anterior lamellar keratoplasty comprising 100 PK and 25 DALK procedures for keratoconus at the (DALK), which r.-volves replacing the anterior part of a diseased corner Singapore National Eye Centre from. April 1992 through December 2006 while retaining the healthy deeper tissue, has the advantage of reducing were included. DALK was performed with the modified An-war the risks of graft rejection and intraocular complications. It is, however, technique (descemetic or DALKa group) in 14 eyes and manual lamellar more technically demanding and may result in suboptimal visual keratoplasty (predescemetic or DALKm group) was performed in 11 outcomes because c:" interface and refractive irregularities. eyes. rejection, which will lead to concomitar--endothelial cell loss with Over the past few decades, several techniques of anterior lamellar • RESULTS: At 12 months, the DALKa and PK groups achieved a keratoplasty (ALK) have been described.5' These include the earlier logarithm of the minimum angle of resolution mean best spectacle- predescemetic procedures in which some stromal tissue and Descemet corrected visual acuity (BSCVA) of 0.15 and 0.27, respectively (P = .26), membrane (DM) are left behind, such as in the manual forms of DALK in whereas the mean BSCVA of the DALKm group was 0.41 compared which manual lamellar surgical dissections were performed. A recent with the PK group (P = .12). Significance level was achieved between the innovation of predescemetic DALK is automated lamellar therapeutic DALKa and DALKm groups (P = .013). There was no significant keratoplasty, which uses microkera-tome instrumentation to perform difference in the mean spherical equivalent (P = .72) and astigmatism (P lamellar dissection. Most recently, descemetic lamellar keratoplasty = .88) between the PK and DALK groups. The DALK group had a procedures have been described in which total stromal removal is at- significantly lower incidence of complications compared with PK cases, tempted, leaving only the DM and endothelium behind, which includes including allograft rejection and glaucoma. Graft survival rate of both the the Anwar big-bubble technique. PK and DALKa groups was 100%, whereas that of the DALKm group This study aimed to compare the optical results of PK and two was 73% at 3 years after surgery (P = .000 between PK and DALKm subgroups of ALK in patients with keratoconus, that is, predescemetic groups). and descemetic techniques. In our population, keratoconus is the fourth • CONCLUSIONS: Visual acuity outcomes of the DALKa technique are most common indication for corneal grafting after pseudophakic and comparable with those of PK for keratoconus, whereas DALK surgery aphakic bullous keratopathy, postinfectious scarring, and regrafts.1 results in fewer postoperative complications than PK. DALKa is Because keratoconus represents low-risk keratoplasty and patients emerging as a preferred choice among the lamellar techniques for better usually are young and free of other ocular pathologic features, they optical outcome. Further studies are required to provide long-term provide an ideal cohort to study success and visual outcomes between analysis of these results. (Am J Ophthalmol 2009;148:744-751. © 2009 lamellar keratoplasty and PK. by Elsevier Inc. All rights reserved.) METHODS A COMPARATIVE COHORT STUDY WAS PERFORMED IN which See accompanying Editorial on page 629. Accepted for publication May 20, 2009. clinical data were retrieved from computerized database of the From the Singapore National Eye Centre (D.C.Y.H., J.S.M., Y.M.P., prospective Singapore Corneal Transplant Study.1 A total of 168 D.T.H.T.); the Singapore Eye Research Institute, Singapore (j.S.M., keratoconus patients underwent H.M.H., D.T.H.T.); and the Department of Ophthalmology (D.T.H.T.), Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore. Inquiries to Donald T. H. Tan, Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore 168751, Republic of Singapore; e-mail: [email protected] 744 0002-9394/09/$36.00 2009 BY ELSEVIER INC. ALL RIGHTS RESERVED. doi:10.101 G/j.ajo.2009.05.028