Optic Disc and Macular Vessel Density Measured by Optical Coherence Tomography-Angiography in Diabetic Patients

Introduction: Diabetes mellitus is a global epidemic, affecting millions of individuals and posing substantial challenges to public health worldwide. Beyond its systemic impact, diabetes gives rise to a myriad of complications, with diabetic retinopathy (DR) emerging as a primary cause of visual impairment and blindness, particularly among the working-age population. DR is a progressive microvascular complication characterized by alterations in the retinal vasculature that can lead to severe vision loss if left untreated. The optic disc and macula, critical components of the retina, are particularly susceptible to these vascular changes, making their comprehensive evaluation imperative for understanding the trajectory of diabetic retinopathy. Optical Coherence Tomography-Angiography (OCT-A) has made it possible to assess and measure early microvascular damage in diabetes, such as capillary nonperfusion and ischemia. While various factors alter the vascular tissue's shape, little is known about how the ocular, systemic, and demographic aspects of diabetes patients affect OCT-A metrics. The study aims to assess the capabilities of Optical Coherence Tomography Angiography (OCTA) to comprehensively investigate optic disc and macular vascular changes in diabetic patients. Materials and methods: Eighteen, 11 Type 1 and 7 Type 2 diabetic patients with or without prior ocular pathology and eight matching healthy individuals were recruited from the clinics at Tobruk Medical Centre. Clinical refractometry, fundus examinations, and imaging by OCT were performed. Results: The foveal thickness was not statistically significant among the studied groups (p =.275), but the central foveal thickness showed a statistical difference among the studied groups (p =.043). Intergroup pairwise comparison revealed that the proliferative diabetic retinopathy (PDR) group had statistically significantly lower central foveal thickness than the severe DR group (p =.045). Conclusion: Different OCT measurements, including focal thickening, may be useful for the early detection of macular thickening and may be indicators for a closer follow-up for diabetic patients.