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Abstract Diabetic macular ischemia is a not only a vision-threatening complication of diabetic retinopathy (Mansour et al. 1993), but also affects the response to treatment and the final visual outcome (Jonas et al. 2005, Chung et al. 2008). FFA is the current gold-standard in the diagnosis and management of diabetic retinopathy (ETDRS 1991a). However, besides its invasive nature, its utility in DMI is limited by its inability to view the intra-retinal vascular networks separately, and by the dynamics of dye transit (such as leakage) which may obscure or superimpose areas of ischemia and the borders of the FAZ (de Carlo et al. 2015). OCTA has the ability to rapidly and non-invasively form segmented images of the macula, allowing visualization of each vascular plexus separately. The vascular flow maps are generated by split-spectrum amplitude-decorrelation angiography (SSADA) which utilizes a motion contrast technology able to detect the flow of RBCs through the intra-retinal capillaries (Jia et al. 2012). We decided to conduct this cross-sectional study on 63 diabetic and 11 control eyes. DMI was quantified in OCTA images of the SCP, ICP, and DCP using four parameters, namely FAZ area, FAZ CI, VAD and VLD. These parameters were then correlated with LogMAR BCVA, age, controls versus diabetics, and duration of diagnosis of DM. Also ICC was calculated between manual and automated measurements and between two graders for ten eyes. We considered our results to be reliable in light of the high ICC recorded between graders and between manual and automated measurements. CI, and VAD were able to differentiate diabetics from non-diabetics. Automated CI was consistently correlated with LogMAR BCVA in diabetic eyes. However, a higher significance was achieved on combination of CI with the other automated parameters. Therefore, OCTA can reliably measure ischemia in diabetic eyes and can correlate these measurements with visual acuity. Further prospective study to investigate the prognostic significance of these results is warranted. |