Optical coherence tomography: limits of the retinal-mapping program in age-related macular degeneration

Abstract

Aim: The retinal-mapping program of Stratus optical coherence tomography (Carl Zeiss Meditec, Dublin, CA, USA) calculates the retinal volume of the central region between the retinal surface and the retinal pigment epithelium (RPE). This study evaluates the retinal-mapping program for studies dealing with AMD.

Methods: The scans of both eyes of patients examined from August to October 2006 because of macular degeneration were evaluated retrospectively. Independent examiners tested whether the two lines indicating the retinal surface and the RPE were positioned correctly by the threshold algorithm that corresponded with correct measurements.

Results: The scans of 233 eyes of 117 patients were evaluated (39.3% were men and 60.7% women, with a mean age of 76.9 years). Overall, in 57.1% both lines were positioned correctly. False-positioned lines were recorded in 9.0% due to low scan quality and in 33.9% due to a doubled or interrupted hyper-reflective band of the RPE. Threshold algorithm misinterpretation was significantly more frequent in occult lesions with and without fibrosis than in non-exudative lesions, and were significantly correlated to distance acuity (p<0.0001).

Conclusion: The retinal-mapping program for examination of AMD provided correct results in only 57.1% of eyes. A manual correction of false-positioned lines would be needed to improve accuracy.