Optical coherence tomography angiography (OCTA) analysis of peripapillary choroidal neovascularization

Abstract

Purpose : Many studies till date that have examined macular CNV vessels using OCTA; exclude or fail to analyze the specific subgroup of peripapillary CNV patients which account for nearly 10 % of the total CNV patients. In a first ever study of peripapillary CNV patients using OCTA, we conducted a cross sectional, observational clinical study to determine the changes in OCTA vessels in a long-term cohort of treated and untreated peripapillary CNV patients to help understand the clinical progression of such patients.

Methods : We analysed 13 eyes treated with anti vegf injections, and 6 untreated eyes imaged on the Spectralis OCT (Spectralis OCT2+HRA; Heidelberg, Germany) over a long term follow up. This was a single center retrospective study of OCTA scans in a cohort of patients’ eyes with peripapillary CNV. We selected OCTA scans free of imaging artifacts for the study. We selected two scans of each eye, one at baseline and one at final visit. Mean interval of follow up for the two groups was 11.9 months for the treated group and 8.08 months for the untreated group. We did manual segmentation correction and analysed the CNV vessels using validated, open source software ImageJ (National Institutes of Health, Bethesda, MD) and Angiotool.

Results : Peripapillary CNV vessels seem to progress over time if left untreated, showing significant increase in lesion area (p=0.036, paired t-test) on imageJ which correlated with angiotool analysis (p=0.0013, paired t-test). In contrast, peripapillary cnv vessels of treated eyes on ImageJ (p<0.0001) and Angiotool(p=0.0004) analysis demonstrated significant reduction after treatment. We found no significant changes in average vessel length in both the groups from baseline to final visit.

Conclusions : Our study shows that peripapillary cnv vessels if left untreated show a trend towards growing over time. These vessels do tend to regress in size after treatment with anti Vegf injections. These findings are the first ever results of peripapillary CNV patients studied using OCTA and will help clinicians get a better understanding of the disease.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

OCTA images of untreated eye at baseline and final visit

 

OCTA images pre and post treatment