The Retinal Nerve Fiber Layer Thickness in Ocular Hypertensive, Normal, and Glaucomatous Eyes With Optical Coherence Tomography

Abstract

OPTICAL COHERENCE tomography (OCT) is one promising technology that has been developed to assess tissue thickness in vivo, such as that of the retinal nerve fiber layer (RNFL). This technology was initially designed for fiberoptic use.¹ Early biological uses of this technology involved imaging of the human anterior chamber, peripapillary retina, and coronary artery.^2-4 Optical coherence tomography has been demonstrated to detect changes in tissue thickness with micrometer-scale sensitivity.^3,5 With a prototype instrument, OCT data were reported to correlate with the known topography of human retinas.⁶ This instrument also performed well in detecting induced RNFL lesions in monkeys.⁷ Reproducibility studies using an OCT prototype have shown SDs of measurement of RNFL and retinal thicknesses of approximately 10 to 20 µm (10%-20%) in normal and glaucomatous eyes.^8-10 Finally, visual field loss correlated with RNFL thickness as determined by this OCT prototype in glaucomatous eyes.⁸