Purpose: To use the retinal thickness analyzer (RTA) and optical coherence tomography (OCT) scanners for quantitative measurement of retinal thickness in eyes with macular disease.
Design: In a cross-sectional study, 44 patients (55 eyes) with macular disease and sufficient media clarity to visualize the fundus using clinical biomicroscopy underwent an ophthalmologic examination, fluorescein angiography, RTA, and OCT during the same visit.
Methods: Foveal and foveal center (foveolar) retinal thickness measurements were obtained by RTA and by OCT.
Results: Retinal thickness measurements were obtained by OCT in all 55 eyes and by RTA in 34 eyes (62%, primarily due to interference from media opacities). In the 34 eyes in which measurements were obtained by both instruments, mean foveal thickness was 291 and 269 microm for OCT and RTA, respectively; foveolar thickness was 277 and 265 microm, respectively. OCT and RTA measurements of foveal thickness were strongly correlated (intraclass correlation coefficient = 0.89), as were measurements of the foveolar thickness (intraclass correlation coefficient = 0.94). Topographic maps generated by the two techniques yielded qualitatively similar information.
Conclusions: Overall, there was excellent agreement between RTA and OCT measurements. Each technique has advantages that may make its use preferable in a particular subgroup of eyes or to describe a particular disease process. An important consideration is that media opacities create less interference for OCT than for RTA, so that in study populations with a moderate-to-high prevalence of media opacity, images can be obtained in a greater percentage of eyes by OCT than by RTA.