Abstract
Purpose: :
The OCT ophthalmoscope can take serial C scan images of the retina, and a three dimensional (3D) image of retina can be constructed from the serial C scan images. From this 3D image, the retinal thickness can be measured anywhere within the area of the image. The purpose of this study was to determine the optimal conditions to measure retinal thickness by OCT ophthalmoscope and to evaluate the efficacy of this method.
Methods: :
The topography mode of the OCT ophthalmoscope (OTI, NIDEK) was used. The area of the C scan image was 15x15° and the recording time was either 2 or 4 seconds. The recording thickness was 1.5 mm. Within the 2 or 4 sec, 100 C scan slices were recorded serially. In normal volunteers, we compared the foveal thickness with recording times of 2 or 4 sec. We also compared foveal thickness with a recording time of 2 seconds with the foveal thickness recorded with the OCT 3000(Carl Zeiss).
Results: :
The foveal thickness measured with the OCT ophthalmoscope ranged from 120 to 190 µm. There was a good correlation between foveal thickness measured in 2 seconds and 4 sec. In normal subjects, all data were from 120 to 200 µm by both methods.
Conclusions: :
The 3–D images obtained by OCT ophthalmoscopy can be used to obtain valid measurements of the foveal thickness, and a recording time of 2 sec is sufficient to measure foveal thickness.
Keywords: retina • macula/fovea • diabetic retinopathy