Review of OCT and fundus images for detection of Macular Edema

Abstract

Macula is an oval shaped area near the center of human retina that covers the area of 5500 microns and at its center, there is a small pit known as fovea with the diameter of 1500 microns. Macular disorders involve group of diseases that damages macula resulting in blindness or vision loss. Macular Edema `ME' is the most common disease related to macula. The symptoms for this disease usually appear in final stages to patient when it is very difficult to cure it and at that time it causes severe damage to central vision. However if it is detected in early stages then it can be easily cured. Different techniques that are used to detect ME are Fundus Photography (also known as Fundography), Fundus Fluorescein Angiography `FFA' and Optical Coherence Tomography `OCT'. Earlier, Fundography was the most widely used test to detect ME. But now a days OCT is being widely used for detecting ME due to its ability to detect small changes in sub-retinal layers. In this paper, we present a detailed comparison between Fundography and OCT imaging technology for the detection of Macular Edema using our own dataset provided to us by Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi. Total 64 patients were studied in this experiment by examining their fundus and OCT images where 15 patients had ME while 49 were healthy persons. OCT images provide an objective evaluation of early macular edema as compared to Fundography. Keywords: Retina, Diabetes, Optical imaging, Coherence, Diseases, Photography