Polypoidal choroidal vasculopathy: evidence-based guidelines for clinical diagnosis and treatment.

BACKGROUND: Polypoidal choroidal vasculopathy (PCV) is an exudative maculopathy affecting vision, with clinical features distinct from neovascular age-related macular degeneration. Currently, no evidence-based guidelines exist for its diagnosis and treatment. METHODS: A panel of experts analyzed a systematic literature search on PCV together with results of the EVEREST trial, the only published randomized controlled clinical trial in PCV. At a subsequent Roundtable meeting, recommendations for the management of PCV were agreed based on this analysis and their own expert opinion. RESULTS: Diagnosis of PCV should be based on early-phase nodular hyperfluorescence from choroidal vasculature visualized using indocyanine green angiography. Recommended initial treatment of juxtafoveal and subfoveal PCV is either indocyanine green angiography-guided verteporfin photodynamic therapy or verteporfin photodynamic therapy plus 3 × 0.5 mg ranibizumab intravitreal injections 1 month apart. If there is incomplete regression of polyps by indocyanine green angiography, eyes should be retreated with verteporfin photodynamic therapy monotherapy or verteporfin photodynamic therapy plus ranibizumab. If there is complete regression of polyps by indocyanine green angiography, but there is leakage on fluorescein angiography and other clinical or anatomical signs of disease activity, eyes should be retreated with ranibizumab. CONCLUSION: Practical guidance on the clinical management of PCV is proposed based on expert evaluation of current evidence.

Angiographic characteristics of acute central serous chorioretinopathy in an Asian population.

INTRODUCTION: Acute central serous chorioretinopathy (CSCR) afflicts young middle-aged males in the Western population. We aimed to analyse patient demographics and to determine the angiographic characteristics of acute CSCR in an Asian population. MATERIALS AND METHODS: This is a retrospective study of all patients presenting with acute CSCR who had fundal fluorescein angiograms performed within a 4-year period (between 1 January 1998 and 31 December 2001). RESULTS: The fluorescein angiograms of 128 patients were analysed. The majority were male (109/128) with a male-to-female ratio of 5.7:1. The age range of patients was 26 to 60 years, with a mean age of 41 years. The majority of patients (84%) were aged 30 to 50 years. With regard to racial distribution, 83% were Chinese, 6% were Malays and 11% were Indians or of other races. Unilateral disease was found in 74 patients (58%) and 52 had bilateral disease. The macula was the most common site of fluorescein leakage and was found in 97 patients (76%). Almost half the patients (44%) had more than one site of disease involvement (i.e., multifocal). The inkblot leakage pattern was found in 103 patients (80%). CONCLUSIONS: The patient demographics of acute CSCR in our population were compared to that reported in the West. The gender ratio was similar, with males being afflicted 6 to 10 times more compared to females. There was no racial predilection found for acute CSCR in the local population. We also found a significant proportion of patients with bilateral and multifocal disease compared to the West. The inkblot pattern of leakage was the most common pattern seen on angiography. There were a significant number of cases with bilateral and multifocal involvement, exceeding those reported in non-Asian populations.

Characterization of Bietti crystalline dystrophy patients with CYP4V2 mutations.

PURPOSE: Mutations of the CYP4V2 gene, a novel family member of the cytochrome P450 genes on chromosome 4q35, have recently been identified in patients with Bietti crystalline dystrophy (BCD). The aim of this study was to investigate the spectrum of mutations in this gene in BCD patients from Singapore, and to characterize their phenotype. METHODS: Nine patients with BCD from six families were recruited into the study. The 11 exons of the CYP4V2 gene were amplified from genomic DNA of patients by polymerase chain reaction and then sequenced. Detailed characterization of the patients' phenotype was performed with fundal photography, visual field testing, fundal fluorescein angiography, and electroretinography (ERG). RESULTS: Three pathogenic mutations were identified; two mutations, S482X and K386T, were novel and found in three patients. The third mutation, a previously identified 15-bp deletion that included the 3' splice site for exon 7, was found in all nine patients, with six patients carrying the deletion in the homozygous state. Haplotype analysis in patients and controls indicated a founder effect for this deletion mutation in exon 7. Clinical heterogeneity was present in the patients. Compound heterozygotes for the deletion in exon 7 seemed to have more severe disease compared to patients homozygous for the deletion. There was good correlation between clinical stage of disease and ERG changes, but age did not correlate with disease severity. CONCLUSIONS: This study identified novel mutations in the CYP4V2 gene as a cause of BCD. A high carrier frequency for the 15-bp deletion in exon 7 may exist in the Singapore population. Phenotype characterization showed clinical heterogeneity, and age did not correlate with disease severity.

Photodynamic therapy for polypoidal choroidal vasculopathy.

The first effective therapy for exudative macular degeneration (AMD) was Photodynamic Therapy (PDT). Diagnosis of the disease was to a large extent by fluorescein angiography (FA). Distinguishing between the leaky choroidal neovessels (CNV) associated with exudative AMD, and the polypoidal structures associated with Polypoidal Choroidal Vasculopathy (PCV) is not always easy using FA alone. The switch to Indocyanine Green angiography helped to pinpoint PCV, and thus to study the efficacy of photodynamic therapy of this particular form of retinal disease, which is more frequently encountered among pigmented individuals. The results appear to be quite promising, and in the year following treatment only a small fraction of the patients had to be retreated. Alternatively, treating PCV with repeated intravitreal VEGF blocking agents was not as successful as it was in the treatment of wet AMD. However, combining PDT-induced angio-occlusion of the polypoidal lesions with anti-vascular endothelial growth factor therapy was shown to be quite effective, and the combination of PDT with an anti-angiogenic agent as well as a steroid, in a triple therapy, was recently also shown to be a quite promising option. In the present article we review the data on PDT of PCV, including combination therapies and alternative treatments. We also report on similarities and differences between AMD and PCV.

The ON/OFF-response in retinopathy of prematurity subjects with myopia.

Retinopathy of prematurity (ROP) is often associated with myopia. Electrophysiological findings have shown that an imbalance of the ON- and OFF-response in subjects with ROP is associated with their refractive status. Nevertheless, the extent of these functional changes is still unclear. The aim of this study was to determine the extent of the ON- and OFF-response attenuation in ROP subjects with myopia. Fast and slow m-sequence multifocal electroretinogram were recorded on 14 eyes in 8 subjects with various degrees of myopia using the VERIS system. The spherical equivalent of refractive error ranged from -0.25 to -13.50 D. All ERG recordings were made using DTL electrodes with dilated pupils. A 19 retinally scaled hexagon stimulus was used. The findings showed that the ON- and OFF-response are reduced differently in ROP subjects with myopia. The ON-response attenuation is dependant on the severity of myopia, whereas, the OFF-response attenuation is influenced by retinal eccentricity as well as the degree of myopia. The contributions of these findings toward the understanding of retinal mechanisms controlling ocular growth need to be further explored.