T H Lim

Polypoidal choroidal vasculopathy: an angiographic discussion

The understanding of polypoidal choroidal vasculopathy has evolved rapidly in the past three decades. The hallmark of the disease is the presence of typical hyperfluorescent nodules in the early phase of indocyanine green angiography. Although the classical clinical presentation is recurrent serosanguinous detachment of the retinal pigment epithelium, it may present with clinical features indistinguishable from exudative age-related macular degeneration secondary to choroidal neovascularization. Some cases may present initially with submacular haemorrhage, but later with features of exudative age-related macular degeneration. Studying the associated network of vessels using confocal scanning laser ophthalmoscopy indocyanine green dynamic angiography revealed in many cases feeder vessels, branching pattern, and leakage similar to choroidal neovascularization. Owing to the overlap of clinical and angiographic features, it may be considered as a vascular subtype of exudative age-related macular degeneration. However, having seemingly better natural history, better response to photodynamic therapy, and incomplete response to anti-vascular endothelial growth factor therapy suggests that it should be studied as a separate entity from choroidal neovascularization. Combining angio-occlusion of the polyps using photodynamic therapy and anti-permeability effect of anti-vascular endothelial growth factor therapy on the branching vascular network may provide a synergistic effect. We await the result of EVEREST trial, a multi-centre randomized controlled trial comparing photodynamic therapy, with or without ranibizumab, with ranibizumab monotherapy.

Epidemiology of pterygium on a tropical island in the Riau Archipelago

ObjectivesTo describe the epidemiology of pterygium among residents of an island in Indonesia and to examine the roles of age and gender as determinants of bilaterality and severity of the disease.MethodsVoluntary eye screening on Pulau Jaloh, Riau Archipelago, Indonesia. Gender difference was tested using the χ2 test. The difference in age between subjects with and without disease was tested using unpaired Students t-test. Odds ratio (relative risk) for gender was calculated using logistic regression model with adjustment for age.ResultsOf the 550 inhabitants, 477 (86.7%) responded to the eye screening. The overall prevalence rate of pterygium was 17.0%. Out of 211, 48 male (22.7%) and 33 out of 266 female subjects (12.4%) had the disorder, with the gender difference being statistically significant. Adjusted for age, the risk of disease was 3.1-fold higher among the males. In all, 71.6% of subjects with pterygium had bilateral disease. Subjects with pterygium were significantly older, their mean age being 42.9 years compared to 18.7 years among those without disease. The prevalence rates in male subjects increased from age 20 to reach a plateau of 63.6% at age 35 and remained stable thereafter. In the female subjects, the rates also increased with age, albeit at a slower rate, from age 20 to reach a plateau of 46.7% at age 55 and remained stable thereafter.ConclusionsThere is a high prevalence rate of pterygium among the study subjects, with the rates increasing rapidly with age.

Validity of EuroQOL-5D, time trade-off, and standard gamble for age-related macular degeneration in the Singapore population

Background/aimsUtility values of age-related macular degeneration (AMD) in Asian patients are unknown. This study aims to assess utility values and construct validity of the EuroQOL-5D (EQ-5D), time trade-off (TTO), and standard gamble (SG) instruments in the Singapore multi-ethnic AMD population.MethodsCross-sectional, two-centre, institution-based study. Visual acuity (VA), clinical AMD severity, and utility scores on the EQ-5D, TTO, and SG were obtained from 338 AMD patients. VA was analysed in terms of the better-seeing eye (BEVA), worse-seeing eye (WEVA), and weighted average of both eyes (WVA). We evaluated SG on the perfect health-death (SG(death)) and binocular perfect vision-binocular blindness (SG(blindness)) scales. Construct validity was determined by testing a priorihypotheses relating the EQ-5D, TTO, and SG utility scores to VA and clinical AMD severity.ResultsThe mean utilities on the EQ-5D, TTO, SG(death), and SG(blindness) were 0.89, 0.81, 0.86, and 0.90, respectively. EQ-5D scores correlated weakly with BEVA, WEVA, and WVA (Pearsons correlation coefficients −0.291, −0.247, and −0.305 respectively, P<0.001 for all). SG(death) and SG(blindness) demonstrated no correlation with BEVA, WEVA, or WVA (Pearsons correlation coefficients, range −0.06 to −0.125). TTO showed weak association only with WEVA and WVA (correlation coefficients −0.237, −0.228, P<0.0001), but not with BEVA (correlation coefficient −0.161). Clinical AMD severity correlated with EQ-5D and SG(death), but not with TTO and SG(blindness) (P=0.004, 0.002, 0.235, and 0.069, respectively).ConclusionsAMD has a negative impact on utilities, although utility scores were high compared with Western cohorts. EQ-5D, TTO, and SG showed suboptimal construct validity, suggesting that health status utilities may not be sufficiently robust for cost-utility analyses in this population.

Dengue retinopathy manifesting with bilateral vasculitis and macular oedema

granuloma as a result of local CD8þ infiltration and that this regressed with commencement of HAART and topical steroids. Scleral granulomas have been found in association with different systemic conditions. To our knowledge this is the first report of scleral granuloma occurring in the presence of presumed DILS. During HIV infection the immune system becomes dysfunctional because of the coexistence of immunodeficiency and immune hyperactivity, and a disregulated production or activity of cytokines, thereby explaining the development of the DILS. Clinicians need to be aware of this entity, which is gaining in significance.

Resolution of severe macular oedema in adult Coat's syndrome with high-dose intravitreal triamcinolone acetonide

ObjectiveTo report the clinical outcome of a patient who received high-dose intravitreal triamcinolone acetonide as treatment for severe macular oedema secondary to adult Coats syndrome.MethodCase report.ResultsA 74-year-old Indian man complaining of chronic gradual blurring of vision in the left eye was found to have adult Coats syndrome with severe macular oedema. He received 25 mg of intravitreal triamcinolone acetonide following unsuccessful resolution with grid laser. Optical coherence tomography (OCT) demonstrated up to 75% decrease in macular oedema that was evident even after 9 months follow-up. However, there was no significant improvement in visual acuity.ConclusionIntravitreal triamcinolone is a reasonable option in reducing severe macular oedema in cases of adult Coats syndrome.

Abnormalities on the multifocal electroretingram may precede clinical signs of hydroxychloroquine retinotoxicity

Abnormalities on the multifocal electroretingram may precede clinical signs of hydroxychloroquine retinotoxicity

Comparison of foveal-sparing with foveal-involving photodynamic therapy for myopic choroidal neovascularization

PurposeTo evaluate the visual outcomes of choroidal neovascularization (CNV) secondary to pathological myopia in eyes treated with photodynamic therapy (PDT), and to determine the effect of lesion location and foveal involvement on visual prognosis.MethodsInterventional case series of 24 consecutive patients with myopic CNV treated with PDT. The main outcome measure was final LogMAR visual acuity (VA).ResultsOf 24 eyes, the CNV lesion was subfoveal in 11 and extrafoveal in 13. Overall, the mean LogMAR VA at 24 months was 0.72. Extrafoveal CNV lesions achieved significantly better final VA compared with subfoveal CNV (LogMAR 0.45 vs 1.05, P=0.012). Eyes with extrafoveal CNV lesions were subdivided into foveal-sparing PDT (where the PDT laser spot did not involve the foveal center) and foveal-involved PDT (where the PDT laser covered the fovea). At all time points, the group with foveal-sparing PDT had significantly better VA compared with the foveal-involved group. The final LogMAR VA for the foveal-sparing PDT group was 0.26 compared with 1.00 for the foveal-involved PDT group (P=0.003). At 24 months, 77.8% of foveal-sparing PDT cases achieved VA of ≥20/40, compared with 25% of foveal-involved PDT cases and 9.1% of subfoveal CNV lesions (P=0.006).ConclusionFor patients with myopic CNV, foveal-sparing PDT results in significantly better long-term visual outcomes compared with those with foveal-involved PDT. Foveal-sparing PDT may be of value for treatment of myopic CNV patients who are not suitable for treatment with anti-vascular endothelial growth factor injections.

Factors affecting visual outcome of myopic choroidal neovascularization treated with verteporfin photodynamic therapy.

AIM To evaluate the visual outcomes of choroidal neovascularization (CNV) secondary to pathological myopia and the impact of novel risk factors affecting the final visual outcome. METHODS Interventional case series of 18 consecutive patients with pathological myopia treated with photodynamic therapy (PDT). Inclusion criteria were spherical equivalent -6D or worse or features of pathological myopia on retinal examination. The main outcome measure was final best-corrected visual acuity (BCVA). RESULTS Of 18 eyes, 13 (72.2%) avoided moderate visual loss (≥3 lines of LogMAR BCVA) and 5 eyes (27.8%) improved by at least 1 line after 1 year. Patients with LogMAR BCVA ≤0.3 (Snellen equivalent 20/40) at one year were younger than those with BCVA >0.3 (mean age 39.0 vs 61.6 years, P=0.001). A higher proportion of eyes with greatest linear dimension (GLD) of ≤1000µm avoided moderate visual loss (100% vs 50%, P=0.026). Among patients who were treated within 2 weeks of visual symptoms, 88.9% avoided the loss of 3 or more lines compared to 55.6% for those who presented later. The mean improvement in LogMAR BCVA of those with GLD ≤1000µm was +0.12 compared to a loss of 0.55 LogMAR units for those with GLD >1000µm (P=0.02). Visual outcomes were not associated with gender or refractive error. CONCLUSION Good visual outcome in myopic CNV is associated with younger age, smaller lesion size and earlier initiation of treatment. These factors are relevant for ophthalmologists considering treatment options for myopic CNV.