DETECTION OF MORPHOLOGICAL RETINAL VASCULAR CHANGES IN DIABETIC RETINOPATHY USING FUNDOSCOPY AND OCTA

Abstract

Diabetic Retinopathy (DR) is a prevalent complication of Diabetes mellitus (DM) that primarily affects the microvasculature of the retina. However, the early stages of retinal microvascular changes can be challenging to diagnose during clinical examinations. Fundoscopy is currently considered the standard method for detecting DR. To address this issue, Optical Coherence Tomography Angiography (OCTA) has emerged as a novel approach for visualizing capillaries in real-time. This study aimed to demonstrate a link between morphological alterations in the retinal vasculature and HbA1c levels using two techniques, fundoscopy and OCTA, also assessing the utility of OCTA in objectively staging DR based on retinal microvascular changes and the potential of OCTA in detecting subclinical disease that may not be visible with fundoscopy. It involved a cross-sectional design with a sample size of 79 DM patients who fulfilled the inclusion criteria. Participants were required to provide written consent after being informed about the study. Detailed medical and ophthalmic histories were recorded, including HbA1c levels. Fundoscopy was done first then, OCTA imaging was performed to visualize the retinal vasculature. Various quantitative parameters were analyzed using specialized software. Statistical analysis was done to look at the relationship between morphological alterations and level of HbA1c. The results offered an insightful information about the correlation between retinal vascular integrity and glycemic control. Our study found a strong correlation between the stages of DR and vascular parameters acquired from OCTA. With different characteristics like the area, perimeter, and circularity of the FAZ and VD showing progressive microvascular abnormalities. There were only weak relationships found between HbA1c levels and OCTA parameters. OCTA parameters, including RE Circularity and LE FAZ Area, and several VD measurements showed statistically significant association with DR stages. Thus OCTA provides an early detection of retinal microvascular changes as compared to fundoscopy. The study also showed weak relationship between HbA1c and duration of diabetes with stages of diabetic retinopathy.