Comparitive Study between OCT in Normal Persons and OCT in Diabetic Patients with no Clinical Diabetic Retinopathy

Abstract

Diabetic retinopathy (DR) is commonly viewed as a microvascular complication of diabetes mellitus. In addition to vascular changes, structural neurodegenerative changes such as neural apoptosis, loss of ganglion cell bodies, glial reactivity, and reduction in thickness of the inner retinal layers have been described in the earliest stages of DR. This loss of neural tissue agrees with previous functional studies showing neuroretinal deficits in patients with diabetes including electroretinogram abnormalities, loss of dark adaptation and contrast sensitivity, color vision disturbances, and abnormal microperimetry. The introduction of optical coherence tomography (OCT) has allowed imaging and measuring of retinal thickness (RT) with high accuracy, and several studies have shown that total RT is decreased in diabetic patients with no DR compared to normal controls. The high resolution of spectral domain OCT (SD-OCT) allows measurement of the thickness of all individual retinal layers after automated three-dimensional segmentation. The aim of the study is the early detection of diabetic retinopathy before clinical signs appear by determining which retinal layers are most affected by diabetes. Forty eyes were included in this study; they were selected from patients who came to the outpatient clinic of the Giza Ophthalmic hospital between March 2015 and May2015. Twenty eyes of diabetic patients with no DR and twenty eyes of normal control persons didn’t have any history of diabetes, other systemic disease or eye pathology.Patients were included if they had a history of diabetes type 2 for 10 years with no DR and exclusion criteria were Refractive errors more thanS+5D or less thanS-8D, Significant media opacity, Previous ocular surgery and any other ocular pathology like glaucoma, uveitis, retinal disease or any other systemic disease.