3-D localization of Diabetic Macular Edema using OCT thickness maps

This paper presents a novel automated system that segments 3-D thickness maps of sub-retinal layers from healthy and abnormal OCT image stacks with Diabetic Macular Edema (DME). These automated thickness maps are well correlated (r > 0.7) with the manually segmented thickness maps. The thickness maps demonstrate highly irregular regions in the inner and outer nuclear layers for patients with DME when compared to the healthy images. The combined area of irregularity in the inner and outer nuclear layers can thereby be extracted as a novel metric with correlation r = 0.99 to track the severity of DME. No other existing automated algorithm has extracted inner sub-retinal layer thickness maps from OCT image stacks of DME patients. The proposed system is fast and robust in locating the sub-retinal changes caused by DME in the 3-D sub-retinal micro-structure.