The morphology of choroidal neovascularization in chronic central serous chorioretinopathy presenting with flat, irregular pigment epithelium detachment

Predict and Protect: Evaluating the Double-Layer Sign in Age-Related Macular Degeneration

INTRODUCTION

Advanced age-related macular degeneration (AMD) is a major cause of vision loss. Therefore, there is interest in precursor lesions that may predict or prevent the onset of advanced AMD. One such lesion is a shallow separation of the retinal pigment epithelium (RPE) and Bruch's membrane (BM), which is described by various terms, including double-layer sign (DLS).

METHODS

In this article, we aim to examine and clarify the different terms referring to shallow separation of the RPE and BM. We also review current evidence on the outcomes associated with DLS: firstly, whether DLS is predictive of exudative neovascular AMD; and secondly, whether DLS has potential protective properties against geographic atrophy.

RESULTS

The range of terms used to describe a shallow separation of the RPE and BM reflects that DLS can present with different characteristics. While vascularised DLS appears to protect against atrophy but can progress to exudation, non-vascularised DLS is associated with an increased risk of atrophy. Optical coherence tomography (OCT) angiography (OCTA) is the principal method for identifying and differentiating various forms of DLS. If OCTA is unavailable or not practically possible, simplified classification of DLS as thick or thin, using OCT, enables the likelihood of vascularisation to be approximated. Research is ongoing to automate DLS detection by applying deep-learning algorithms to OCT scans.

CONCLUSIONS

The term DLS remains applicable for describing shallow separation of the RPE and BM. Detection and classification of this feature provides valuable information regarding the risk of progression to advanced AMD. However, the appearance of DLS and its value in predicting AMD progression can vary between patients. With further research, individualised risks can be confirmed to inform appropriate treatment.

Pachychoroid neovasculopathy versus macular neovascularization in age-related macular degeneration with and without shallow irregular pigment epithelial detachment

To compare the choroidal neovascular features of individuals with pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) with and without shallow irregular pigment epithelial detachment (SIPED). Using optical coherence tomography angiography, the choroidal neovascular complexes of 27 patients with PNV, 34 patients with nAMD and SIPED, and 15 patients with nAMD without SIPED were analyzed with FIJI and AngioTool software. PNV compared to nAMD with SIPED had a greater vessel percentage area (P = 0.034), junction density (P = 0.045), average vessel length (P < 0.001), and fractal dimension (P < 0.001). PNV, compared to nAMD without SIPED, had a greater total vessel length (P = 0.002), total number of junctions (P < 0.001), junction density (P = 0.034), and fractal dimension (P = 0.005). nAMD with SIPED, compared to nAMD without SIPED, had greater vessel area, total number of junctions, total vessel length, and average vessel length (all P values < 0.001). Patients with nAMD plus SIPED and individuals with nAMD without SIPED have similar fractal dimension values (P = 0.703). Biomarkers of choroidal neovascular complexity, such as fractal dimension, can be used to differentiate PNV from nAMD with or without SIPED.

EFFECTS OF HALF-DOSE PHOTODYNAMIC THERAPY ON CHRONIC CENTRAL SEROUS CHORIORETINOPATHY WITH OR WITHOUT MACULAR NEOVASCULARIZATION ASSESSED USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To assess the effects of half-dose photodynamic therapy on subretinal fluid and macular neovascularization (MNV) using optical coherence tomography angiography in patients with chronic central serous chorioretinopathy.

METHODS

Clinical information on 168 patients (168 eyes) with chronic central serous chorioretinopathy obtained before and 6 months after treatment with half-dose photodynamic therapy was retrospectively analyzed. Patients were categorized into a success (145 eyes) or failure (23 eyes) group based on the absence or presence of subretinal fluid, respectively, and clinical data were compared between them. Macular neovascularization was studied in 147 cases with available optical coherence tomography angiography images. P < 0.05 indicated statistical significance.

RESULTS

The success group showed a younger patient age, better posttreatment best-corrected visual acuity, and thicker pretreatment central choroidal thickness (all, P < 0.047) than did the failure group. Regarding MNV analysis, nine, eight, and 130 eyes had definite, possible, and no MNV, respectively, at baseline; among them, 100.0%, 75.0%, and 2.3%, respectively, had MNV at 6 months posttreatment. Patients with definite MNV at baseline were less likely to show successful subretinal fluid resolution.

CONCLUSION

Although half-dose photodynamic therapy is generally effective for the treatment of chronic central serous chorioretinopathy, coexisting MNV may compromise the outcome; thus, optical coherence tomography angiography-based assessment of chronic central serous chorioretinopathy is important.