Correlation between Findings of Optical Coherence Tomography And Optical Coherence Tomography Angiography in Patients with Diabetic Macular Ischemia

Abstract
Background: Diabetic Macular Ischemia (DMI) is a variant of diabetic maculopathy that can be overlooked but has serious implication on management of Diabetic Retinopathy (DR) and Diabetic Macular Edema (DME).
Aim of Study: The aim of the study was to study the findings of OCT (optical coherence tomography) and OCTA (optical coherence tomography angiography) in patients with DMI and correlate them.
Patients and Methods: A cross sectional study that included 30 eyes: 20 eyes with DMI as diagnosed by FFA (fundus fluorescein angiography) and 10 healthy eyes as control. Both groups underwent OCT and OCTA imaging. OCT images were assessed for thickness and structural abnormalities. Macular perfusion was quantified using OCTA images by 2 parameters: FAZ (foveal avascular zone) area and VAD (vessel area density) at 2 levels; SCP (superficial capillary plexus) and DCP (deep capillary plexus).
Results: A statistically significant difference as regard values of FAZ area and VAD in both SCP and DCP, using OCTA, was found between patients and control groups.
There was a statistically significant correlation between the retinal thickness of ischemic macular areas and SCP FAZ area, SCP VAD and DCP VAD. DRIL (disorganization of retinal inner layers) was found in 55% of patients. A statistically significant correlation was found between the presence of DRIL and both SCP FAZ area and SCP VAD (r=0.755, pConclusion: OCTA is able to detect and quantify DMI and it can substitute FFA for that purpose. OCT can detect ischemic areas of the macula as these areas appear to be thinner than normal and to show disorganization of its inner retinal layers.