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This paper describes a new digital image processing algorithm which is concerned with the automatic detection and measurement of the foveal avascular zone (FAZ) in.Fundus Fluorescein Angiographies (FFA). FFA is used in ophthalmic practice to evaluate vascular retinopathies and choroidopathies. In the proposed algorithm, projection in the horizontal and vertical directions will be applied to determine the location of the dark regions in the test image that represents the region of interest (FAZ). Then. image is segmented based on its gray level values by using thresholding techniques. Morphological operators and Sobel edge detector are then used to detect and localize the contour of the FAZ.

Background: Diabetic retinopathy is one of the common microvascular complications of diabetes. The formation of advanced glycation end products (AGE) exerts deleterious effects by acting directly to induce cross-linking of proteins promoting vascular damage. Hyperglycemia causes disturbance in glycogenesis pathway resulting in reduction of glucose to sorbitol which is converted to fructose by sorbitol dehydrogenase. Methods: The levels of advanced glycation end products (AGE), lipid profile, and glycosylated Hb were estimated in 266 type I diabetic patients without retinopathy, patients with nonproliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy patients (PDR).The association between genotypes of two polymorphisms of sorbitol dehydrogenase gene (SDH) was estimated in the promoter region: a C/G transversion located at _1214 position and a G/C transversion at _888 position. This study showed allele-specific PCR for C-1214G polymorphism and restriction fragment length polymorphism (RFLP) technique for a G/C transversion at _ 888 position. Results: Significant increase was detected in glycosylated Hb levels in diabetic group, both with retinopathy and without retinopathy. Also, a significant increase in Hb1c in PDR group compared to NPDR. Significant increase in total cholesterol, HDL, TG, and AGE in PDR group compared to the group without retinopathy. No significant change was observed in the same parameter between PDR and NPDR group. Significant increase in AGE in both PDR and NPDR group compared to the group without retinopathy. No significant change in PDR group compared to NPDR. The results of this study showed no significant difference in genotype distribution (C/C, C/G, G/G) of the C˗1214G polymorphism between the two groups of patients with and without DR A2-. There was no statistically significant difference between the three genotypes (CC, CG, and GG) of the C˗1214G polymorphism in relation to DR severity in male genders. However, there was a statistically significant difference in female gender with increased frequency of CC genotype (2.7%, 21.9%, and 23.7%). There was no significant difference in genotype distribution (C/C, G/C, and G/G) of the G˗888C polymorphism between the two groups of patients with DR and without DR. However, the CC genotype occurred more frequently in patients with DR than patients without DR (6.7% vs. 3.9%), and G/G genotype occurred more frequently in

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Background: Diabetic retinopathy is a multistage event, and the most important of it is angiogenesis. The possible association between vascular endothelial growth factor (VEGF) +405G/C gene polymorphism and various diseases, in which angiogenesis might be critical in disease development, encourages many investigators to study its role in diabetic retinopathy (DR) development in diabetics. The aim of this work is to investigate +405G/C polymorphism of VEGF gene in Egyptian patients with type 1 diabetes mellitus (T1DM) and to assess its possible role as a predictor for the development and progress of diabetic retinopathy. A cross-sectional, observational study was undertaken in a sample of type I diabetic patients who attend diabetes polyclinic of RIO Hospital, Giza, Egypt, between October 2012 and December 2016 and who were willing to participate. Two hundred and sixty-six type 1 diabetic patients were studied (108 males and 158 females). All subjects were analyzed for VEGF +405G/C polymorphism by real-time PCR using TaqMan pre-designed single nucleotide polymorphism (SNP) genotyping assay. Results: There were increased serum levels of VEGF in T1DM suffering from DR compared to those without. Also, there was increased +405 C/C of VEGF polymorphism and C allele frequency related to the severity of DR (nonproliferative retinopathy (NPR), proliferative diabetic retinopathy (PDR), and macular edema (ME)) and type C phenotype (ischemic) in T1DM suffering from DR. Conclusion: Serum levels of VEGF and its +405G/C polymorphism could be used in the evaluation, development, and progression of DR.