Abstract

Background: Optical coherence tomography angiography (OCTA) is a novel non-invasive application of OCT to study the dynamic function of retinal vasculature. Diabetic retinopathy is a sequelae of microvascular changes in the retina and OCTA can be used to assess these changes at the level of superficial (SCP) and deep capillary plexus (DCP).

Methods: A prospective, comparative observational study of 60 eyes of 49 patients (30 eyes of 19 patients with NPDR and 30 eyes of healthy subjects) attending Ophthalmology outpatient clinic at Research Institute of Ophthalmology, Giza, Egypt between September 2018 to April 2019. All patients underwent spectral domain optical coherence tomography (SD-OCT) and angiography (OCTA) of the macula using Heidelberg Spectralis OCT, Germany.

Results: Thirty eyes of 19 patients with NPDR were compared with 30 eyes of healthy subjects as the control group. There was a clinically significant difference noticed in foveal avascular zone (FAZ) surface area, horizontal and vertical diameter and central macular thickness (CMT) in diabetic group compared to the healthy subjects at both SCP and DCP levels.

Conclusion: This study suggest that OCTA has a role as a non-invasive tool in early detection of macular microvascular changes in diabetic patients and to study the superficial and deep capillary plexus without the need for Fluorescein angiography (FA).

Keywords: Optical Coherence Tomography (OCT); Optical Coherence Tomography Angiography (OCTA); Foveal Avascular Zone (FAZ); Superficial Capillary Plexus (SCP); Deep Capillary Plexus (DCP)

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