International Journal of Ophthalmology & Visual Science 2022; 7(1): 6-13 http://www.sciencepublishinggroup.com/j/ijovs doi: 10.11648/j.ijovs.20220701.12 ISSN: 2637-384X (Print); ISSN: 2637-3858 (Online) Comprehensive Foveal Avascular Zone and Retinal Evaluation with Their Correlation to Visual Acuity and Glycemic Control in Diabetics Without Macular Edema Mohamed M. Halfawy 1 , Abelrahman Gaber Salman 1 , Azza M. A. Said 1 , Tarek El Beltagi 2 , Marwa A. Karim 1 1 Faculty of Medicine, Ain Shams University, Cairo, Egypt 2 Research Institute of Ophthalmology, Giza, Egypt Email address: To cite this article: Mohamed M. Halfawy, Abelrahman Gaber Salman, Azza M. A. Said, Tarek El Beltagi, Marwa A. Karim. Comprehensive Foveal Avascular Zone and Retinal Evaluation with Their Correlation to Visual Acuity and Glycemic Control in Diabetics Without Macular Edema. International Journal of Ophthalmology & Visual Science. Vol. 7, No. 1, 2022, pp. 6-13. doi: 10.11648/j.ijovs.20220701.12 Received: December 31, 2021; Accepted: January 19, 2022; Published: January 25, 2022 Abstract: Background: Evaluating Foveal avascular zone by OCTA (Optical Coherence Tomography angiography) in diabetic patients, has a crucial role in early detection of pathophhsiological changes affecting the macular area, and has a pedective value for early retinal neuro degenerative changes. Materials and experiments: Aim: To evaluate dimensions of Foveal Avascular Zone (FAZ) at level of superficial and deep capillary plexuses (SCP/DCP) in patients with different grades of non proliferative diabetic retinopathy without Diabetic Macular Edema (DME) using OCTA. Eighty type II diabetes mellitus patients and 20 healthy control, ecxluding proliferative diabetic retinopathy and DME. Divided to four groups according to ETDRS Classification. All undewent: measurement of glycosylated hemoglobin level, standard Structural OCT for the macula and optic nerve head with OCTA for evaluation of FAZ in both SCP and DCP networks of all eyes using (Heidelberg engineering, OCT spectralis, Germany) (SD-OCT). Results: Mean FAZ in SCP in control group (0.32 ± 0.12) mm 2 versus (0.44 ± 0.17) mm 2 in patients` group, while FAZ IN DCP (0.23) mm 2 ± 0.12 in controls versus (0.34 ± 0.16) mm 2 in patients. There was a statistically significant wider FAZ in DR patients (P-value 0.003). Conclusion: Enlargement of FAZ in SCP and DCP in patients with moderate to severe NPDR without DME was detected using OCTA, Preceeded by reduction in thickness of ORL and GCC layer. This can be used to monitor the progression of the disease and to evaluate the response to treatment. Keywords: Diabetic Retinopathy, Foveal Avascular Zone, Optical Coherence Tomography Angiography 1. Background Diabetic retinopathy (DR) is the major preventable blindness cause between working-age individuals in most of the developed countries, affecting one in three diabetic patients [1, 2]. The most frequent ocular complication is diabetic retinopathy (DR), which may range from being asymptomatic and may progress to severe vision loss [3]. The diabetic maculopathy, which include diabetic macular oedema (DME) and diabetic macular ischemia (DMI) are considered the most serious sight-threatening complications of DR [4], Moreover PDR cosequential complications like - vitreous haemorrhage and retinal detachment. Early detection of DR and DME in routine screening of diabetics could be done by thorough analysis of retinal fundus digital images [5-7]. Although it has high sensitivity and specificity, it has a low negative predictive value [7]. Optical Coherence Tomography (OCT) is privileged by being a non-invasive, rapid imaging modality that uses low- coherence interferometry to capture high resolution two dimensional images from different retinal layers optical scattering, thus allows imaging of the cross-sectional structures of the retina [8] OCT considered a vital tool for DME detection and monitoring [9] besides evaluation of DMI and inner retinal thinning [10]. Optical coherence tomography angiography (OCTA) is a novel breakthrough, allows retina and choroid microvasculature visualization without dye injection [11]. Its mechanism depends on repeated scans at the same location with detection of OCT reflectance signal