Reproducibility of Spectral-Domain Optical Coherence Tomography RNFL Map for Glaucomatous and Fellow Normal Eyes in Unilateral Glaucoma

PURPOSE:To compare the reproducibility of the optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness map between glaucomatous and fellow normal eyes of unilateral glaucoma patients. METHODS:In this prospective case-control study, Cirrus HD-OCT was performed for 79 unilateral glaucoma patients 3 times on the first visit and on 3 subsequent visits within a 2-month period. Test-retest standard deviation (TRT-SD) and tolerance limit based on the 1.645×√2×TRT-SD formula were derived for RNFL thicknesses at the respective superpixels of the RNFL thickness map. RESULTS:The TRT-SDs and tolerance limits of the glaucomatous eyes (TRT-SD2.75 to 20.25 μm; tolerance limits6.40 and 47.11 μm) were significantly smaller than those of the fellow normal eyes (TRT-SD2.73 to 26.49 μm; tolerance limits6.35 and 61.63 μm) in the superotemporal, inferotemporal, and superonasal areas (P