Optical Coherence Tomography Assessment of Macular and Choroidal Thickness in Patients with Proliferative Diabetic Retinopathy in Relation to HbA1C

Abstract

SUMMARY D iabetic retinopathy, also known as diabetic eye disease, is when damage occurs to the retina due to diabetes, It can eventually lead to blindness. Diabetic Retinopathy affects up to 80 % of all patients who have had diabetes for 10 years or more. Despite these intimidating statistics, research indicates that at least 90% of these new cases could be reduced if there were proper treatment and monitoring of the eyes. Each year in the United States, diabetic retinopathy accounts for 12% of all new cases of blindness. Diabetic Retinopathy is a progressive disease predominantly affects the integrity of the microscopic vessels found in the retina. Diabetic retinopathy can be broadly divided into two clinical stages: non proliferative and proliferative diabetic retinopathy. Proliferative diabetic retinopathy develops following the occlusion of retinal capillaries leading to retinal ischemia, which promotes the development of neovascularization, a process by which new blood vessels proliferate on the surface of the retina and these vessels are fragile and bleed easily. The resulting accumulation of blood in the vitreous cavity from these hemorrhaging vessels seriously impairs vision. This impairment of vision may be permanent due to further complications such as traction retinal detachment. It has been estimated that without treatment for proliferative diabetic retinopathy, 50% of all patients will become blind within 5 years following diagnosis. With the help of optical coherence tomography, it is now possible to measure the macular and choroidal thickness objectively and to follow the progression of diabetic retinopathy quantitatively. And periodic glycosylated haemoglobin measurements can reflect the long-term control of hyperglycaemia. Intensive glycemic control had been proved to be effective in decreasing incidence rate of development and progression of diabetic retinopathy in type 1 and type II diabetic mellitus as demonstrates by diabetes control and complication trials. We conducted our study to evaluate the relation of macular and choroidal thickness to glycosylated haemoglobin in patients with proliferative diabetic retinopathy The study included 72 eyes of 63 patients with a diagnosis of proliferative diabetic retinopathy. Patients have been recruited from Retinal clinic in Memorial Institute of Ophthalmological Research and were asked to participate in the study. The study was designed as an observational, cross-sectional and non-coherent study in the period from 2/2016 to 7/2016.