Assessment of Retinal Microvascular Changes by OCT Angiography in Diabetic Retinopathy

This observational cross-sectional study aims to assess retinal microvascular changes using optical coherence tomography angiography (OCTA) in patients with diabetic retinopathy. The study will evaluate retinal vessel density and foveal avascular zone parameters and investigate their correlation with best-corrected visual acuity and glycemic control (HbA1c) across different stages of diabetic retinopathy. The findings may improve understanding of retinal microvascular alterations and their clinical significance.

Inclusion Criteria: \- Inclusion Criteria: * Adults aged 18 to 80 years. * Patients diagnosed with diabetic retinopathy. * Ability to undergo complete ophthalmic examination including OCT and OCT angiography. * Availability of HbA1c measurement within the study period. * Ability and willingness to provide written informed consent. Exclusion Criteria: * Previous vitreoretinal surgery. * Significant media opacity affecting image quality (e.g., dense cataract or vitreous hemorrhage). * Other retinal vascular diseases (e.g., retinal vein occlusion). * Glaucoma or optic nerve diseases affecting visual function. * High myopia (\>6 diopters). * Poor-quality OCTA images due to motion artifacts or poor fixation. * Refusal or inability to provide informed consent. Exclusion Criteria: \-