Comparison of Foveal Avascular Zone Parameters in Diabetic Retinopathy and Normal Retina on Optical Coherence Tomography Angiography Using Automated Software
DOI:
https://doi.org/10.51985/Keywords:
Angiography, Diabetic retinopathy, Optical coherence tomographyAbstract
Objective: To compare Foveal Avascular Zone (FAZ) metrics comprising of FAZ area, perimeter and circularity between individuals afflicted with diabetic retinopathy and those exhibiting healthy, normal retinal profile by using built in algorithm of Optical coherence tomography angiography (OCT-A)
Study Design and Setting: It was an observational study. Conducted at the Ophthalmology Department, PNS Shifa Hospital, Karachi from October 2023 to December 2024.
Methodology: 60 patients participated which included 30 type 2 diabetics with mild to moderate non proliferative diabetic retinopathy (NPDR), without macular involvement and 30 non diabetics age matched normals. FAZ parameters of OCTAngio Optopol revo nx130 (Area, Circularity and Perimeter) were calculated and compared between two groups using automated built in software. FAZ parameters of mild and moderate NPDR were compared within diabetic group.
Results: Mean age in diabetics was 55.33 ± 6.85 years and in non-diabetics 55.30± 4.94 years. On comparison of FAZ parameters the area and perimeter were statistically significantly enlarged as compared to non-diabetics FAZ parameters (p < 0.001). The circularity index was lower among diabetics as compared to non-diabetics (p < 0.001). Among the diabetic patients there was a statistically significant enlargement of FAZ area in moderate NPDR versus mild NPDR (p <0.001) and difference of FAZ perimeter (p = 0.07) and circularity index (p =0.60) were statistically insignificant.
Conclusion: Diabetic patients with mild to moderate NPDR having clinically normal appearing maculae show deranged FAZ parameters on OCT-A as compared to age matched normal healthy retinae
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