Purpose. The treatment of diabetic macular edema is based on the detection of retinal thickening. The present assessment of clinically significant macular edema (CSME), based on stereo-photography and ophthalmoscopy, is subjective and can be difficult. We have developed a method of rapid mapping of the retinal thickness and applied it to study retinal thickening in eyes with CSME. Methods. The measurements were performed on a commercial (Talia Technology Ltd., Israel) prototype of the Retinal Thickness Analyzer (RTA). Ten optical sections were digitized in 200 msec via a video camera. Nine macular areas were scanned to cover the central 20° of the fundus. The images were analyzed by an operator-free algorithm to yield a map of the retinal thickness. 31 eyes with diabetic CSME were examined clinically, photographed and scanned with the RTA. A masked reader trained in systematic methods of ETDRS grading drew the edematous areas from the photographs. These areas were compared to areas on the RTA map with thickening significantly above normal (p<0.025). Results. The foveal thickness with the RTA reached values between normal and 2.7 times normal (mean 1.5 times). The maximal retinal thickness in each eye varied between normal and 2.1 times normal. The maximal thickness within a disc diameter of the fovea correlated with Snellen visual acuity (r=0.7). There was an overall agreement between the RTA map and the masked reader as to the presence of CSME though there were cases without CSME on RTA. A quantitative and detailed comparison between the reader assessment and the RTA will be presented with the reasons for disagreement. Conclusion. Rapid mapping of the retinal thickness with the RTA provides a quantitative and objective assessment of retinal thickening and macular edema. The method may enhance the objectivity and reliability of the assessment of CSME.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Dec 1 1997|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience