Comparison between Retinal Ophthalmoscopy Vs Fundus Photography with ETDRS Field for Clinical Screening of Diabetic Retinopahty

Abstract

BACKGROUND Screening of Diabetic retinopathy is essential for detection of diabetic retinopathy and its management. Diabetic retinopathy is a common and preventable cause of blindness in adults. Laser pan-retinal photocoagulation has been proven to have established efficacy in treating diabetic visual loss. Since India has a wide geographical area and there is a lack of trained ophthalmologists in peripheral India, there is an immense need for telemedicine in diabetic retinopathy screening. This study was done to evaluate the comparability of non-stereoscopic fundus photography with conventional fundoscopy for detection of diabetic maculopathy. METHODS All patients with diabetic retinopathy and mixed retinopathy presenting to Ophthalmology OPD at Sri Siddhartha Medical College between June 2020 and June 2021, were included in the study. The patients were evaluated for visual acuity on Snellen Visual Acuity Chart, Anterior Segment evaluation on a slit-lamp examination. Fundus was evaluated with 90 Diopter Volk lens with Slit Lamp biomicroscopy, Direct Ophthalmoscopy with Welch Allyn ophthalmoscope with medium size aperture, and the peripheral fundus was seen by an Indirect Ophthalmoscope with 20 Diopter lens Volk lens. ETDRS 7 Field Picture on Carl Zeiss Meditec AG VISUCAM SN model AA107 was taken. The observations were subjected to the statistical analysis of Cohen’s Kappa and the percentile description. RESULTS The commonest retinopathy was moderate non-proliferative diabetic retinopathy (NPDR), seen in 41.667 %. The commonest maculopathy found was the absence of maculopathy seen in 78.3 % of cases. There was perfect agreement (Kappa k-1.00) in the evaluation of background retinopathy on Conventional Fundoscopy and Fundus imaging, P-value < 0.001. There was moderate agreement (Kappa k-0.5) in the evaluation of maculopathy on Conventional Fundoscopy and Fundus imaging, Pvalue < 0.001, only for CSME and No maculopathy. However diffuse macular oedema and Ischemic Maculopathy were missed on Fundus Photography. CONCLUSIONS Non-Stereoscopic Fundus Photography is a good telemedicine tool for diabetic retinopathy screening, but there is under-diagnosis of it, though it can detect diabetic maculopathy. As a diagnosis”Absence of maculopathy” is inconclusive until and unless screened by Conventional Ophthalmoscopy. KEY WORDS Diabetic Retinopathy, Maculopathy, Clinically Significant Macular Oedema, NonStereoscopic Fundus Imaging, Ophthalmoscopy.