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Choroidal Vascularity Index in Retinitis Pigmentosa: An OCT Study
Background And Objective:
To evaluate structural changes in the choroid of patients with retinitis pigmentosa (RP) using swept-source optical coherence tomography (OCT) scans.
Patients And Methods:
A prospective study was conducted comparing 35 eyes of 35 patients with RP and 26 eyes of 26 normal patients. OCT images of the choroid were binarized into luminal and stromal areas to derive choroidal vascularity index (CVI). Subfoveal choroidal thickness (CT) was also measured and compared.
Results:
There was a significant decrease in the mean CVI among eyes with RP as compared to normal eyes (56.91 ± 1.43% vs. 59.47 ± 1.55%; P < .0001). Mean subfoveal CT was significantly greater in eyes with RP as compared to normal eyes (262.82 μm ± 69.69 μm vs. 194.65 μm ± 23.55 μm; P < .0001).
Conclusion:
Patients with RP showed a significant reduction in CVI and an increase in CT as compared to normal eyes. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:191-197.].
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