Phenotypic and genetic variations between Asian and Caucasian polypoidal choroidal vasculopathy

Imaging characterization of the fellow eye in patients with unilateral polypoidal choroidal vasculopathy

INTRODUCTION

New insights on polypoidal choroidal vasculopathy (PCV) have shed light regarding its pathophysiology and associations. However, PCV characterization is still incomplete in Caucasians, which is due to presumed lower prevalence in this population. Features typically associated with AMD such as drusen, retinal pigmentary changes or atrophy are seen in PCV, as precursors and in the fellow eye. Pachychoroid spectrum, predisposing to PCV, also presents with chronic changes in the retinal pigment epithelium (RPE), such as drusen-like deposits (DLD), and in the choroid. The purpose of this study is to perform a multimodal imaging characterization of unaffected fellow eyes in a sample of Caucasian patients with unilateral PCV.

METHODS

Multicenter retrospective cohort study with a sample of 55 unaffected fellow eyes from patients diagnosed with unilateral PCV confirmed by indocyanine green angiography. The sample was characterized in the baseline by color fundus photography, spectral domain optical coherence tomography (SD-OCT), fluorescein angiography and indocyanine green angiography. Morphological characteristics of both the retina and the choroid were evaluated. The SD-OCT of the last follow-up visit was also evaluated in order to exclude evolution to PCV or choroidal neovascularization. All images captured underwent evaluation by two independent graders. Informed consent was obtained from all participants.

RESULTS

Fifty-five patients (median age, 74 ± 15 years) were included. After 15.5 ± 6.4 months of follow-up, only one developed disease (1.9%). Soft and/or hard drusen were present in 60% and pachydrusen in 23.6%. Pachychoroid signs were present in 47.2%, the double-layer sign in 36.4%, disruption of the RPE changes in 16.4% and RPE atrophy in 10.9%. ICGA revealed choroidal vascular dilation in 63.6% and punctiform hyperfluorescence in 52.7%. Branching vascular networks were identified in only 1.9% of cases.

CONCLUSION

The identification of pachychoroid signs in the OCT and ICGA were present in over half of the cases and the presence of the double-layer sign in more than a third provide crucial insights for enhanced characterization of this pathology and deeper understanding of its pathogenesis. These findings contribute significantly to the current knowledge, offering valuable markers to discern various phases of the pathology's progression.

Macular neovascularization and polypoidal choroidal vasculopathy: phenotypic variations, pathogenic mechanisms and implications in management

Advances in imaging have led to improved ability to characterize variations in clinical sub-phenotypes of macular neovascularization (MNV) in Age-related macular degeneration (AMD). Polypoidal choroidal vasculopathy (PCV) was initially described based on characteristic features observed in indocyanine green angiography (ICGA) and was thought to be a distinct entity from AMD. However, subsequent careful observations based on confocal scanning laser ophthalmoscopy-based ICGA, optical coherence tomography (OCT) and OCT angiography have led researchers to appreciate similarities between PCV lesion and type 1 MNV in typical neovascular AMD. Concurrently, clinical trials have shown that anti-VEGF monotherapy can achieve favourable visual outcome in the majority of eyes with PCV. These learnings have led to a shift in the way PCV is managed over the past decade. Recent studies have supported the use of non-ICGA based imaging modality to screen for PCV and the adoption of anti-VEGF monotherapy as initial therapy for PCV. A focus of recent research has been in the understanding of the role of choroidal alterations in the pathogenesis of PCV. The concept of pachychoroid in leading to outer retinal ischemia has garnered increasing support. Future research in this area should evaluate the potential of choroidal morphology in guiding personalized therapy in PCV.

Polypoidal Choroidal Vasculopathy: Updates on Risk Factors, Diagnosis, and Treatments

There have been recent advances in basic research and clinical studies in polypoidal choroidal vasculopathy (PCV). A recent, large-scale, population-based study found systemic factors, such as male gender and smoking, were associated with PCV, and a recent systematic review reported plasma C-reactive protein, a systemic biomarker, was associated with PCV. Growing evidence points to an association between pachydrusen, recently proposed extracellular deposits associated with the thick choroid, and the risk of development of PCV. Many recent studies on diagnosis of PCV have focused on applying criteria from noninvasive multimodal retinal imaging without requirement of indocyanine green angiography. There have been attempts to develop deep learning models, a recent subset of artificial intelligence, for detecting PCV from different types of retinal imaging modality. Some of these deep learning models were found to have high performance when they were trained and tested on color retinal images with corresponding images from optical coherence tomography. The treatment of PCV is either a combination therapy using verteporfin photodynamic therapy and anti-vascular endothelial growth factor (VEGF), or anti-VEGF monotherapy, often used with a treat-and-extend regimen. New anti-VEGF agents may provide more durable treatment with similar efficacy, compared with existing anti-VEGF agents. It is not known if they can induce greater closure of polypoidal lesions, in which case, combination therapy may still be a mainstay. Recent evidence supports long-term follow-up of patients with PCV after treatment for early detection of recurrence, particularly in patients with incomplete closure of polypoidal lesions.

Different Morphology of Branching Neovascular Network in Polypoidal Choroidal Vasculopathy: A Swept-Source Optical Coherence Tomography Angiography Study

Purpose: To evaluate the classification system of branching neovascular network (BNN) morphology in polypoidal choroidal vasculopathy (PCV) patients based on swept-source optical coherence tomography (SS-OCT) and swept-source optical coherence tomography angiography (SS-OCTA), and analyze the morphological features in each group as potential prognostic features. Methods: A total of 32 PCV eyes were included in this retrospective study. SS-OCT and SS-OCTA images of 6 mm × 6 mm centered on the foveal of each eye were analyzed. PCV cases were classified into three types ("trunk", "glomeruli", and "stick" type) based on the morphological features of BNN. OCT and OCTA features were compared among the three groups. The correlation of OCT/OCTA features with visual acuity at 12 months after anti-VEGF treatment was also analyzed. Results: Type 1 group had the largest BNN area and the largest numbers of polypoidal lesions. Type 2 group has the largest pigment epithelial detachment (PED) area, PED volume, subretinal fluid (SRF) area, and SRF volume. Type 3 group had better baseline BCVA, the smallest BNN area, the smallest PED size, and the smallest SRF size. Type 1 was also featured by a clear break on Bruch's membrane which corresponded to the origin of neovascular tissue. BCVA at 12 months was not significantly different among groups. Baseline BCVA and baseline central macular thickness were correlated with the final BCVA. Conclusions: The current classification system based on BNN morphology on SS-OCTA was highly applicable and revealed distinct characteristics in each group. The BNN type was not correlated with BCVA at 12 months after treatment.

Real-world cost-effectiveness of anti-VEGF monotherapy and combination therapy for the treatment of polypoidal choroidal vasculopathy

OBJECTIVES

For patients with polypoidal choroidal vasculopathy (PCV), intravitreal anti-vascular endothelial growth factor (anti-VEGF) combination therapy has been shown to be cost-saving relative to monotherapy in a clinical trial setting. However, whether this also applies to real-world settings is unclear. We aim to compare the real-world functional outcomes and cost-effectiveness of intravitreal anti-VEGF combination therapy relative to monotherapy, to investigate whether combination therapy is truly cost-saving.

METHODS

We used a Markov model to simulate a hypothetical cohort of PCV patients treated at Singapore National Eye Centre. Model parameters were informed by coarsened exact matched estimates of a two-year retrospective study of patients who initiated treatment in 2015. Treatment options included intravitreal aflibercept, bevacizumab, or ranibizumab, as monotherapy or in combination with full-fluence verteporfin photodynamic therapy.

RESULTS

The two-year logMAR letters gains were significant for combination therapy ( + 10.6, P = 0.006) but not monotherapy (-2.2, P = 0.459). Over 20 years, a PCV patient would cost the health system SGD 48,790 under monotherapy and SGD 61,020 under combination therapy. Quality-adjusted life-years (QALYs) were estimated to be 7.41 for monotherapy and 7.80 for combination therapy. The incremental cost-effectiveness ratio of combination therapy was SGD 31,460/QALY, which is less than the common willingness-to-pay threshold of per capita gross domestic product of Singapore (SGD 88,990/QALY). Sensitivity analysis showed that combination therapy remained incrementally cost-effective, but not cost-saving.

CONCLUSIONS

Our study shows that combination therapy is good value for money but is likely to increase costs when applied in real-world settings.

Current Trends in Clinical Characteristics, Diagnosis, and Treatment of Polypoidal Choroidal Vasculopathy: A Perspective from Vietnam

Polypoidal choroidal vasculopathy (PCV) is a common choroidal disease in the Asian population including Vietnam and is characterized by subretinal red-orange nodules, pigmented epithelium detachment, and massive subretinal hemorrhage. The recent focus on PCV in Vietnam can be attributed to advancements in PCV diagnosis and treatment. However, there is a scarcity of published literature and clinical data on PCV in the Vietnamese population, highlighting a key knowledge gap in this region. In order to address this gap, we gathered the opinions of experienced clinicians and retinal experts in Vietnam and reviewed available medical literature with the aim of: (i) providing an overview of PCV in the Vietnamese population—in terms of epidemiology, clinical characteristics, and management; (ii) tailoring international/national guidelines for the diagnosis and management of PCV, in line with available resources and medical equipment in Vietnam; and (iii) identifying gaps in clinical data in order to guide future PCV research in Vietnam and other countries with similar clinical conditions. The present review will enable healthcare providers and researchers to gain insight into current clinical practices and the limitations of PCV management in Vietnam and provide optimal and effective solutions.

Thermal Laser Monotherapy for Extrafoveal Polypoidal Choroidal Vasculopathy

INTRODUCTION

Polypoidal choroidal vasculopathy (PCV) is a vascular disease of the choroid. Diagnosis is mainly based on polypoidal aneurysm-like lesions seen in indocyanine green (ICG) angiography. Various therapeutic options have been proposed.

METHODS

Outcomes of 10 cases with extrafoveal PCV and consecutive macular edema treated with thermal laser are reported. Diagnosis of PCV was confirmed by ICG angiography.

RESULTS

Upon successful occlusion of the polyps in 10 eyes after thermal laser treatment demonstrated in ICG angiography, a regression of central foveal edema was seen in optical coherence tomography and color fundus photography. Visual acuity improved from logMAR 0.8 to logMAR 0.3. Follow-up ranged from 4 months to 15 years, with a median of 1 year. Two eyes had a recurrence of exudative maculopathy 5 and 7 years after laser treatment, respectively.

CONCLUSION

A careful differentiation between various subforms of exudative maculopathy using fluorescein and ICG angiography can identify certain selected patients with extrafoveal PCV, for whom thermal laser monotherapy can be a therapeutic option.