Adrian Koh

EVEREST study: efficacy and safety of verteporfin photodynamic therapy in combination with ranibizumab or alone versus ranibizumab monotherapy in patients with symptomatic macular polypoidal choroidal vasculopathy.

Purpose: To assess the effects of verteporfin photodynamic therapy (PDT) combined with ranibizumab or alone versus ranibizumab monotherapy in patients with symptomatic macular polypoidal choroidal vasculopathy. Methods: In this multicenter, double-masked, primarily indocyanine green angiography–guided trial, 61 Asian patients were randomized to verteporfin PDT (standard fluence), ranibizumab 0.5 mg, or the combination. Patients were administered with verteporfin PDT/placebo and initiated with three consecutive monthly ranibizumab/sham injections starting Day 1, and re-treated (Months 3–5) as per predefined criteria. The primary endpoint was the proportion of patients with indocyanine green angiography–assessed complete regression of polyps at Month 6. Secondary endpoints included mean change in best-corrected visual acuity at Month 6 and safety. Results: At Month 6, verteporfin combined with ranibizumab or alone was superior to ranibizumab monotherapy in achieving complete polyp regression (77.8% and 71.4% vs. 28.6%; P < 0.01); mean change ± standard deviation in best-corrected visual acuity (letters) was 10.9 ± 10.9 (verteporfin PDT + ranibizumab), 7.5 ± 10.6 (verteporfin PDT), and 9.2 ± 12.4 (ranibizumab). There were no new safety findings with either drug used alone or in combination. Conclusion: Verteporfin PDT combined with ranibizumab 0.5 mg or alone was superior to ranibizumab monotherapy in achieving complete regression of polyps in this 6-month study in patients with symptomatic macular polypoidal choroidal vasculopathy. All treatments were well tolerated over 6 months.

Polypoidal choroidal vasculopathy and neovascular age-related macular degeneration: Same or different disease?

Neovascular age-related macular degeneration (nAMD) is the commonest cause of severe visual impairment in older adults in Caucasian white populations. Polypoidal choroidal vasculopathy (PCV) has been described as a separate clinical entity differing from nAMD and other macular diseases associated with subretinal neovascularization. It remains controversial as to whether or not PCV represents a sub-type of nAMD. This article summarizes the current literature on the clinical, pathophysiological and epidemiological features and treatment responses of PCV and compares this condition to nAMD. Patients with PCV are younger and more likely Asians, and eyes with PCV lack drusen, often present with serosanguinous maculopathy or hemorrhagic pigment epithelial detachment, and have differing responses to photodynamic therapy and anti-vascular endothelial growth factor (VEGF) agents. There are also significant differences in angiographic and optical coherence tomography features between PCV and nAMD. Histopathological studies suggest differences in the anatomical details of the associated vascular abnormalities in the retina and choroids and the relative role of VEGF. There is emerging evidence of common molecular genetic determinants involving complement pathway and common environmental risk factors (e.g. smoking). Such information could further assist clinicians involved in the care of elderly patients with these conditions.

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.

Association Analysis of CFH, C2, BF, and HTRA1 Gene Polymorphisms in Chinese Patients with Polypoidal Choroidal Vasculopathy

PURPOSE Polypoidal choroidal vasculopathy (PCV) is a major cause of serosanguinous maculopathy in Chinese patients with age-related macular degeneration (AMD). Variants in the CFH and HTRA1/LOC387715 genes are strongly associated with AMD in Caucasians and Chinese. Variants in the C2 and BF genes have been found to confer a significantly reduced risk of AMD. This study was undertaken to determine whether these associations occur in Chinese patients with PCV. METHODS Patients of Chinese ethnicity with clinically and angiographically diagnosed PCV and normal control subjects were recruited from the Singapore National Eye Centre. Five single-nucleotide polymorphisms (SNPs) in the CFH gene, two each within the C2 and BF genes and two variants located in the LOC387715 and HTRA1 genes, were screened in all patients and control subjects. RESULTS Seventy-two patients with PCV and 93 normal control subjects were studied. A significant association was noted with CFH variants rs3753394 and rs800292 among the PCV cases (P = 0.0015 and P = 0.0045, respectively). Individuals homozygous for the TT genotype of rs3753394 had a significantly higher risk (P = 0.0076) of PCV (OR = 4.29; 95% CI: 1.47-12.50) than those carrying a single copy of the T allele (P = 0.3210; OR = 1.69; 95% CI: 0.60-4.78), after adjustment for such risk factors as age and sex. The genotype frequencies of rs11200638 and rs10490924 in HTRA1 and LOC387715, respectively, were also found to be significantly different between patients with PCV and normal control subjects (P = 0.00032 and P = 0.003, respectively). The AA genotype of rs11200638 and TT genotype of rs10490924 conferred a 4.9-fold (95% CI: 1.85-12.95) and 4.89-fold (95% CI: 1.85-12.90) increased risk of PCV, respectively, after adjustment for age and sex. The Y402H variant of CFH (rs1061170) and the BF and C2 variants were not significantly different in patients and normal control subjects. CONCLUSIONS The SNPs rs3753394 and rs800292 of CFH and rs11200638 of HTRA1 are significantly associated with the risk of PCV in Chinese patients.

Interventions to retard myopia progression in children: an evidence-based update.

TOPIC To evaluate the efficacy of interventions such as eyedrops, bifocal lenses, or contact lenses in retarding the progression of myopia in myopic children. CLINICAL RELEVANCE Myopia is a common ocular disorder, and high myopia (myopia at least -6.0 diopters) is associated with potentially blinding conditions. At present, there are no general guidelines on interventions that may decrease myopia progression in children, but some interventions such as contact lenses are offered on an ad hoc basis. METHODS OR LITERATURE REVIEWED: English and non-English language articles published from 1968 to 2000 were retrieved using a keyword search of MEDLINE, Embase, Cochrane Library, and Science Citation Index databases. Randomized controlled trials with comparisons of the effectiveness of interventions to decrease myopia progression in myopic children were reviewed. RESULTS Ten clinical trials of different interventions to retard myopia progression were reviewed, including three trials that evaluated atropine and one trial that evaluated soft contact lenses. Atropine eye drops of 0.5% concentration were effective in clinical trials, but no significant effect was found for tropicamide or timolol eyedrops. Five of the six trials on bifocal spectacle lenses with various additions failed to show significant retardation, and results of the remaining trial were barely significant (P = 0.047). A trial of soft contact lenses failed to show significant effects. CONCLUSIONS The latest evidence from randomized clinical trials does not provide sufficient information to support interventions to prevent the progression of myopia. Long-term large-scale double-masked randomized clinical trials, including cycloplegic refraction, are needed before any recommendations about interventions in clinical practice to prevent high myopia in myopic children are considered.

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.

Efficacy and Safety of Ranibizumab With or Without Verteporfin Photodynamic Therapy for Polypoidal Choroidal Vasculopathy: A Randomized Clinical Trial

Importance Polypoidal choroidal vasculopathy (PCV) is a common subtype of exudative age-related macular degeneration among Asian individuals. To our knowledge, there are no large randomized clinical trials to evaluate intravitreal ranibizumab, with and without verteporfin photodynamic therapy (vPDT), for the treatment of PCV. Objective To compare the efficacy and safety of combination therapy of ranibizumab and vPDT with ranibizumab monotherapy in PCV. Design, Setting, and Participants A double-masked, multicenter randomized clinical trial of 322 Asian participants with symptomatic macular PCV confirmed by the Central Reading Center using indocyanine green angiography was conducted between August 7, 2013, and March 2, 2017. Interventions Participants were randomized 1:1 to ranibizumab, 0.5 mg, and vPDT (n = 168; combination therapy group) or ranibizumab, 0.5 mg, and sham PDT (n = 154; monotherapy group). All participants received 3 consecutive monthly ranibizumab injections, followed by a pro re nata regimen. Participants also received vPDT/sham PDT on day 1, followed by a pro re nata regimen based on the presence of active polypoidal lesions. Main Outcomes and Measures Step 1 assessed whether combination therapy was noninferior (5-letter margin) to monotherapy for change in best-corrected visual acuity from baseline and superior in complete polyp regression. If noninferiority was established, step 2 assessed whether combination therapy was superior to monotherapy measured by best-corrected visual acuity change at month 12. Results Baseline demographics of the 322 participants were comparable between the treatment groups. Mean (SD) age of the patients was 68.1 (8.8) years, and overall, 69.9% of the patients were men. At baseline, the overall mean best-corrected visual acuity and mean central subfield thickness were 61.1 letters and 413.3 &mgr;m, respectively. At 12 months, mean improvement from baseline was 8.3 letters with combination therapy vs 5.1 letters with monotherapy (mean difference, 3.2 letters; 95% CI, 0.4-6.1), indicating that combination therapy met the predefined criterion for noninferiority as well as being superior to monotherapy (P = .01). Combination therapy was also superior to monotherapy in achieving complete polyp regression at month 12 (69.3% vs 34.7%; P < .001). Over 12 months, the combination therapy group received a median of 4.0 ranibizumab injections compared with 7.0 in the monotherapy group. Vitreous hemorrhage was the only ocular serious adverse event (combination therapy group, 1 [0.6%]; monotherapy group, 3 [2.0%]). Conclusions and Relevance After 12 months, combination therapy of ranibizumab plus vPDT was not only noninferior but also superior to ranibizumab monotherapy in best-corrected visual acuity and superior in complete polyp regression while requiring fewer injections. Combination therapy should be considered for eyes with PCV. Trial Registration clinicaltrials.gov Identifier: NCT01846273.

Toll-Like Receptor 3 Polymorphism rs3775291 Is Not Associated with Choroidal Neovascularization or Polypoidal Choroidal Vasculopathy in Chinese Subjects

Background/Aims: Age-related macular degeneration (AMD) is a leading cause of visual impairment. A single-nucleotide polymorphism (SNP; rs3775291) in the Toll-like receptor 3 (TLR3) gene has recently been implicated in the pathogenesis of AMD in Caucasian populations. The aim of this study was to examine this association in Chinese persons with choroidal neovascularization (CNV) secondary to AMD and polypoidal choroidal vasculopathy (PCV). Methods: This was an observational cross-sectional study in Singapore. Study subjects were of Chinese ethnicity and included patients with exudative maculopathy and normal control subjects. The diagnoses of CNV and PCV were made based on fundus examination, fluorescein angiography and indocyanine green angiography findings. Genomic DNA was extracted, and genotypes were determined by bidirectional DNA sequencing. We compared the allele and genotype frequencies between subjects with CNV and PCV with controls using the software PLINK. Results: A total of 246 subjects with exudative maculopathy (consisting of 126 with CNV and 120 with PCV) and 274 normal control subjects were recruited. The distribution of rs3775291 SNP genotypes for CNV and PCV was not significantly different from that for normal controls. Conclusion: This study indicates that the TLR3 rs3775291 gene polymorphism is not associated with CNV and PCV in Singaporean Chinese patients.

Bietti’s crystalline dystrophy in Asians: clinical, angiographic and electrophysiological characteristics

This article describes nine Chinese patients with Bietti’s crystalline dystrophy, including two families, one consisting of three siblings and the other a pair of sisters. All patients had the classic refractile deposits located in all layers of the retina, with varying degrees of pigment epithelium atrophy. However, paralimbal crystals were not seen in the anterior corneal stroma. We describe clinical, angiographical and electrophysiological characteristics, and also review the literature on Bietti’s crystalline dystrophy. All patients had full eye examination, including best corrected visual acuity, biomicroscopy, applanation tonometry and dilated funduscopy. Fluorescein angiography and indocyanine green angiography were performed, together with visual fields and electrophysiologic studies. All nine of our patients were phenotypically heterogeneous, with varying age and symptoms at presentation, as well as different degrees of progression. Age was not found to be a predictor of severity. The differences in disease severity, even within sibling groups, suggested that perhaps other factors were at play in phenotypic expression. We found that in early ICGA, all stages of BCD had delayed choroidal filling, which has not been previously described. We also observed a relative derangement of inner choroidal circulation as evidenced by late hypofluorescence on the ICGA. However, it is as yet unclear whether this circulatory disturbance is due to primary involvement of the posterior ciliary arteries, or secondary to choroidal and/or retinal pigment epithelial atrophy. While the FA and ICGA findings were similar, we found that the true extent of the atrophic areas was better delineated by ICGA. ICGA was also superior in outlining the degree and extent of choroidal vascular compromise.

Polypoidal Choroidal Vasculopathy: Definition, Pathogenesis, Diagnosis, and Management

Polypoidal choroidal vasculopathy (PCV) is an age-related macular degeneration (AMD) subtype and is seen particularly in Asians. Previous studies have suggested disparity in response to intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents between PCV and typical AMD, and thus, the preferred treatment for PCV has remained unclear. Recent research has provided novel insights into the pathogenesis of PCV, and imaging studies based on OCT suggest that PCV belongs to a spectrum of conditions characterized by pachychoroid, in which disturbance in the choroidal circulation seems to be central to its pathogenesis. Advances in imaging, including enhanced depth imaging, swept-source OCT, en face OCT, and OCT angiography, have facilitated the diagnosis of PCV. Importantly, 2 large, multicenter randomized clinical trials evaluating the safety and efficacy of anti-VEGF monotherapy and combination with photodynamic therapy (PDT) recently reported initial first-year outcomes, providing level I evidence to guide clinicians in choosing the most appropriate therapy for PCV. In this review, we summarize the latest updates in the epidemiologic features, pathogenesis, and advances in imaging and treatment trials, with a focus on the most recent key clinical trials. Finally, we propose current management guidelines and recommendations to help clinicians manage patients with PCV. Remaining gaps in current understanding of PCV, such as significance of polyp closure, high recurrence rate, and heterogeneity within PCV, are highlighted where further research is needed.