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Updated: Jan 20, 2026

Dissection of Human Retina and RPE-Choroid for Proteomic Analysis
Published on: November 12, 2017
New Insights on Choroidal Vascularity: A Comprehensive Topographic Approach
Abhilash Goud1, Sumit Randhir Singh1,2, Niroj Kumar Sahoo1
1LV Prasad Eye Institute, Hyderabad, India.
Purpose:
To obtain a choroidal vascularity index (CVI) map of macular area on an Early Treatment Diabetic Retinopathy Study (ETDRS) grid.
Methods:
The study was a cross-sectional study involving 30 eyes of 30 healthy individuals. In brief, a shadow-compensated automated algorithm was used to segment and binarize the individual optical coherence tomography (OCT) B-scans. This was followed by three-dimensional reconstruction of these processed B-scans to obtain the overall thickness and vascularity maps. ETDRS grid was overlaid on both the extrapolated thickness and vascularity maps to obtain the corresponding sector-wise CVI. The main outcome measure was to evaluate the topographical variation of CVI in the macular area.
Results:
The mean age of the study participants was 44.33 ± 16.29 years (range, 18-70 years). CVI showed no significant difference in different rings, subfields, or quadrants of the ETDRS map. CVI had a negative correlation with age (r = -0.384, P = 0.03). There were no statistically significant differences between CVI of both eyes in either rings or the full ETDRS grid (P = 0.30) among normal subjects.
Conclusions:
The variation in CVI does not follow similar patterns as seen in choroidal thickness (CT) in various locations. The novel choroidal vascularity mapping in the macular area may expand understanding on regional differences of choroidal vasculature in healthy eyes.
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