Abstract
Abstract: :
Purpose:To validate the reproducibility of retinal mapping program using the newly developed optical coherence tomography, NeOCT EG–Scanner (EG) (Microtomography Inc.) and to compare the results with Humphrey OCT 2000 (OCT2000). METHODS: (1) Standardized Study: To standardize retinal thickness measurements by 2 OCT's (EG and OCT2000), we compared the measurement results of the slide grass, which thickness is determined by the precision gauge, by 2 OCT's. The accuracy of measurement was assessed. (2) Reproducibility Study: We repeatedly scanned the macular area in 22 eyes of 11 normal subjects using EG retinal mapping program in different time, 0, 5, 15 minutes, 1, 3, 6, 9 and 24 hours, in a same day by one examiner. The reproducibility was calculated. (2) Comparison Study: We observed the macular area of normal volunteer (n=3), diabetic macular edema (n=7) and branched retinal vein occlusion with macular edema (n=14) using EG and OCT2000, one after another at the same time in a same day. The retinal mapping results were compared between 2 OCT's. Results: (1) The measurement of the slide grass by EG and OCT2000 was significantly correlated with the precision measurement and the linear regression formula were {EG} = 1.01 X {slide grass} (R2=0.999) and {OCT2000} = 0.95 X {slide grass} (R2=0.999), respectively. (2) In the normal subjects, the reproducibility of retinal mapping program was good. The reproducibility in the measurement in the central area was especially good (Friedman test, p=0.83). (3) The measurement results in 9 areas of the retinal mapping program by EG and OCT2000 were compared. The mean thickness by EG was 365.3 (±103.2) a mark of micrometer and that by OCT2000 was 371.1 (±100.6) a mark of micrometer. The measurement results of 2 OCT's were significantly correlated (R=0.77, P=<0.001). The linear regression formula: {Thickness by EG} = 0.99 X {Thickness by OCT2000}. Conclusions: The measurement of retinal mapping program using EG was well reproducible in the multiple measurements in a same day. The measurement of retinal mapping program u sing EG was slightly thinner than OCT2000, and that by EG was closer to direct measurement than OCT2000.
Keywords: imaging/image analysis: clinical • macula/fovea • retina