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Evaluation of Retinal Vascularity Index in Patients with COVID-19: A Case-Control Study
Sandy Zhou Wenting1, Ankita Shrivastav2, Trupti Gilada3,4
1Khoo Teck Puat Hospital, Ophthalmology and Visual Science, National Health Group Eye Institute, Tan Tock Seng Hospital, Singapore, 308433, Singapore.
Introduction:
The purpose of this study was to evaluate the impact of COVID-19 infection on retinal microvasculature by topographically mapping the retinal arteriole-to-venule ratio (AVR).
Methods:
In a comparative cross-sectional case-control study, fundus photos were obtained in COVID-19-infected patients and healthy controls. AVT was measured over 16 points across the retina using retinal vascularity index (RVI)-a novel semi-automated computerized parameter based on retinal vasculature.
Results:
A total of 51 COVID-19-positive patients and 65 healthy controls were enrolled in the study. Overall, the mean RVI of all 16 points across the retina was 0.34 ± 0.02 in patients with COVID-19 and 0.33 ± 0.02 in control subjects (p = 0.64). Out of the 16 points being measured, three points had a statistically significant greater value in patients with COVID compared to normal controls.
Conclusion:
Localised greater RVI values were found in some of the points in COVID-19-positive patients, which likely indicates a more focal change of the vasculature.
