Analysis of foveal avascular zone in different stages of non/proliferative diabetic retinopathy at a tertiary eye care hospital

To evaluate changes seen in Foveal Avascular Zone (FAZ) on Fundus Fluorescein Angiography in different stages of Non-proliferative Diabetic Retinopathy (NPDR) and its association with systemic conditions like hyperlipidemia, hypertension and nephropathy.

All diabetic patients visiting our MS Ramaiah hospital were screened for diabetic retinopathy from September 2012 to September 2015. The sample size was 30 eyes of 21 patients and duration of study was 2 years.

Among 21 patients 80% of the study populations were males. Majority of patients (53%) were in the age group of 51 to 60 years. In our study, poor glycemic control is significantly associated with severe Non-proliferative Diabetic Retinopathy with p<0.001. In severe NPDR 50% patients had grade 2 outline, 20% had grade 3 outline and in moderate NPDR 60% patients had grade 2 outline. Thus, greater incidence of macular ischemia was seen in patients with more advanced forms of NPDR. 16.6% had altered renal profile in our study of which 60% had grade 2 FAZ outline changes and 40% had grade 3 FAZ outline changes. Thus a significant association was found between FAZ outline and nephropathy.

Macular ischemia thus appears to be a marker for the severity of diabetic retinal disease and other systemic disorders like nephropathy. As is proven in our study the presence of structural and morphologic changes in the perifoveal circulation correlates significantly with changes in visual function and presence of metabolic disorders like nephropathy. Effective screening of all diabetic patients may aid in early diagnosis of diabetic maculopathy and nephropathy and thereby prevent the associated ocular and systemic morbidity and mortality.