Boon Kwang Loh

A Prospective Study of Treatment Patterns and 1-Year Outcome of Asian Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy

Objective To study the treatment patterns and visual outcome over one year in Asian patients with choroidal neovascular membrane secondary to age-related macular degeneration (AMD-CNV) and polypoidal choroidal vasculopathy (PCV). Design Prospective cohort, non-interventional study. Methods 132 treatment-naïve patients who received treatment for AMD-CNV and PCV were included. All patients underwent standardized examination procedures including retinal imaging at baseline and follow-up. AMD-CNV and PCV were defined on fundus fluorescein angiography and indocyanine green angiography at baseline. Patients were treated according to standard of care.We report the visual acuity (VA) and optical coherence tomography (OCT) measurements at baseline, month 3 and month 12 The factors influencing month 12 outcomes were analyzed. Main Outcome Measure Type of treatment, number of Anti-vascular endothelial growth factor (VEGF) treatments, visual outcome over one year. Results Anti-VEGF monotherapy was the initial treatment in 89.1% of AMD-CNV, but only 15.1% of PCV. The mean number of anti-VEGF injections up to month 12 was 3.97 (4.51 AMD-CNV, 3.43 PCV, p = 0.021). Baseline OCT, month 3 OCT and month 3 VA were significant in determining continuation of treatment after month 3. At month12, mean VA improved from 0.82 (∼20/132) at baseline to 0.68 (∼20/96) at month 12 (mean gain 6.5 ETDRS letters, p = 0.002). 34.2% of eyes (38/113 eyes) gained ≥15 ETDRS letters and 14.4% (16/113 eyes) lost ≥15 ETDRS letters. There were no significant differences in visual outcome between AMD-CNV and PCV (p = 0.51). Factors predictive of month 12 visual outcome were baseline VA, baseline OCT central macular thickness, month 3 VA and age. Conclusions There is significant variation in treatment patterns in Asian eyes with exudative maculopathy. There is significant visual improvement in all treatment groups at one year. These data highlight the need for high quality clinical trial data to provide evidence-based management of Asian AMD.

Choroidal thickness and risk characteristics of eyes with myopic choroidal neovascularization

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Trends and factors related to outcomes for primary rhegmatogenous retinal detachment surgery in a large asian tertiary eye center.

Purpose: To describe trends and outcomes of vitreoretinal surgery for primary rhegmatogenous retinal detachment in a large Asian tertiary eye center. Methods: Retrospective review of 1,530 eyes with primary retinal detachment between 2005 and 2011 managed at the Singapore National Eye Center by one of the following: scleral buckling (SB), pars plana vitrectomy (PPV), and combined SB and PPV (SB + PPV). Anatomical and functional outcomes were assessed. Results: There was a trend toward PPV and PPV + SB as the primary reattachment procedure from 2005 to 2011. The primary anatomical success rate for PPV (78.6%) was worse than that for SB (88.8%) or SB + PPV (89.0%, P = 0.000). Final anatomical success rates were similar for all 3 procedures: SB 97.7%, PPV 95.2%, and SB + PPV 96.4%. Better functional success was achieved in the SB group (86.1%) than both the PPV (72.5%) and SB + PPV groups (77.5%, P = 0.000), partly attributable to the less complex nature of retinal detachments in the SB group. Older age and proliferative vitreoretinopathy were related to the poor functional outcomes in both phakic and pseudophakic eyes. Conclusion: There was an increasing trend toward PPV and PPV + SB as the primary retinal reattachment surgery from 2005 through to 2011. High rates of anatomical and functional outcomes were achieved with SB, PPV, and SB + PPV, proliferative vitreoretinopathy and older age were negatively correlated with the functional success in both phakic and pseudophakic eyes.

Prevalence and clinical correlates of focal choroidal excavation in eyes with age-related macular degeneration, polypoidal choroidal vasculopathy and central serous chorioretinopathy

Purpose To describe the prevalence and clinical characteristics of focal choroidal excavation (FCE) in patients with exudative maculopathy due to age-related macular degeneration with choroidal neovascularisation (AMD-CNV), polypoidal choroidal vasculopathy (PCV) and central serous chorioretinopathy (CSC). Methods Three hundred and forty-three patients (343 presenting eyes and 255 fellow unaffected eyes) from consecutive patients presenting with untreated AMD-CNV, PCV or CSC are prospectively recruited. Two independent retinal specialists masked to the clinical diagnosis graded the presence of FCE by examining the findings from spectral-domain optical coherence tomography (SD-OCT). The frequency and clinical characteristics of FCE in each of the three clinical diagnosis groups were compared. Results The diagnosis in the presenting eye was AMD-CNV in 92 patients, PCV in 149 patients, retinal angiomatous proliferation (RAP) in 3 patients and CSC in 99 patients; 255 fellow eyes free of clinical diseases were also graded. The prevalence of FCE was 2.3% (total 14 eyes; 10 presenting eyes, 4 fellow eyes) out of 598 eyes examined. In presenting eyes, FCE was most prevalent in PCV (6.0%), followed by AMD-CNV (1.0%) and CSC (0%), p=0.02. In fellow eyes, the prevalence of FCE was 2.9%, 0% and 1.2% in patients with PCV, AMD-CNV and CSC, respectively. Eyes with FCE had a significantly longer axial length (24.93±1.65 mm vs 23.49±1.10 mm, p<0.001), but otherwise, all other characteristics were similar. Conclusions FCE is more common in PCV than AMD-CNV and CSC. Disturbance in the choroid/retinal pigment epithelium/Bruch membrane interface affected by FCE may be linked to the pathogenesis of PCV and AMD-CNV.

SCLERAL BUCKLING VERSUS VITRECTOMY IN THE MANAGEMENT OF MACULA-OFF PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT: A Comparison of Visual Outcomes.

Purpose: To compare visual outcomes between pars plana vitrectomy (PPV) with or without scleral buckling (SB) and SB alone in the management of uncomplicated macula-off primary rhegmatogenous retinal detachment. Methods: Case–control study of 723 patients with uncomplicated macula-off primary rhegmatogenous retinal detachment seen at the Singapore National Eye Centre from 2005 to 2011. The primary outcome measure was the proportion of eyes achieving functional success, defined as logMAR best-corrected visual acuity of ⩽0.3 logMAR at 6 months postoperatively. Multivariable logistic regression analysis was performed adjusting for the following preoperative covariates: age, gender, race, lens status, number of tears found, presence of proliferative vitreoretinopathy, operative procedure, logMAR best-corrected visual acuity, and duration of symptoms. Results: Three hundred and eight eyes underwent SB alone, and 415 eyes underwent PPV ± SB. In the SB group, 133 eyes (43.2%) achieved functional success compared with 116 eyes (28.0%) in the PPV ± SB group. This difference was statistically significant on both univariate (P < 0.001) and multivariable analyses (OR: 1.51, 95% CI: 1.03–2.21, P = 0.03). Conclusion: Scleral buckling alone may achieve visual outcomes that are at least comparable with PPV ± SB in the management of macula-off primary rhegmatogenous retinal detachment.

Trends in age-related macular degeneration management in Singapore.

Purpose To describe the trends and patterns of anti–vascular endothelial growth factor (anti-VEGF) therapy and photodynamic therapy (PDT) use for age-related macular degeneration (AMD) in the National Eye Centre in Singapore over a 4-year period. Methods Data on the total number of intravitreal anti-VEGF injections and PDT treatment over a 4-year period at the Singapore National Eye Centre were obtained from centralized electronic records. Patients aged 40 years and older treated for AMD were included. Data retrieved included the annual treatment load in terms of number of new patients and total treatment episodes, and treatment burden for patients was studied in terms of number of injections per year and cumulative injection numbers over 3 years. Potential influence on retreatment by choice of drug, use of adjunct PDT, and diagnosis of polypoidal choroidal vasculopathy were further analyzed. Results From 2009 to 2012, a total of 6157 injections were performed on 1380 unique individual patients. The total number of injections performed per calendar year increased from 962 in 2009 to 2278 in 2012. The number of unique incident cases increased from 287 in 2009 to 446 in 2012. The mean number of injections over the first year increased from 2.62 in 2009 to 3.19 in 2012 (p < 0.001). Choice of anti-VEGF therapy did not significantly alter the cumulative injections required. Patients diagnosed as having polypoidal choroidal vasculopathy had similar injection episodes (p = 0.178), whereas choice of anti-VEGF and adjunct PDT had no effect on the overall treatment. Conclusions Anti-VEGF treatment of AMD continues to increase substantially year on year in the past few years, in alignment with experience from other countries. However, the cumulative number of injections per patient remains low, and many patients discontinue treatment within the first year. These data demonstrate that undertreatment remains a significant concern in clinical settings.

MYOPIC RETINOSCHISIS IN ASIANS: Structural Features and Determinants of Visual Acuity and Prognostic Factors for Progression.

Purpose: To describe microstructural changes and schisis extent in eyes with myopic retinoschisis and to determine their influence on visual acuity at baseline and follow-up. Methods: In this prospective observational study, 50 eyes of 38 patients with myopic retinoschisis were evaluated using spectral domain optical coherence tomography, and the patients were followed for at least 12 months. The presence of microstructural changes and the extent of retinoschisis at baseline on spectral domain optical coherence tomography, and the association between these parameters and the risk of visual acuity deterioration were analyzed. Results: Median presenting visual acuity and central retinal thickness were 0.31 logMAR (≈20/40) and 395 &mgr;m, respectively. Twenty-six eyes (52%) had entire macular area retinoschisis. Common microstructural changes included photoreceptor detachment (24%), foveal ellipsoid zone (EZ) disruption (34%), partial-thickness macular hole (26%), and full-thickness macular hole (16%). Visual acuity was poorer in eyes with photoreceptor detachment, EZ disruption, full-thickness macular hole, and central retinal thickness >300 &mgr;m. Eyes with entire macular area retinoschisis had the poorest visual acuity and thickest central retinal thickness, and they were more likely to have photoreceptor detachment, EZ disruption, and retinal detachment. Over a mean follow-up of 31.7 ± 7.7 months, 14 eyes (28%) had worsening visual acuity of ≥2 lines. Ten of these 14 eyes had entire macular retinoschisis at baseline. Conclusion: Most eyes with myopic retinoschisis remain stable. However, eyes with extensive retinoschisis involving the entire macular area are more likely to progress and have microstructural abnormalities and poorer vision. Early surgery should be considered for these eyes.