Retinal Nerve Fiber Layer Measurement Variability with Spectral Domain Optical Coherence Tomography.
- Author:
Jung Taeck HONG
1
;
Kyung Rim SUNG
;
Jung Woo CHO
;
Sung Cheol YUN
;
Sung Yong KANG
;
Michael S KOOK
Author Information
- Publication Type:Original Article
- Keywords: Optical coherence tomography; Reproducibility; Retinal nerve fiber layer; Tracking system
- MeSH: Adult; Algorithms; Anatomy, Cross-Sectional; Female; Humans; Male; Nerve Fibers; Ophthalmoscopes; Reference Values; Reproducibility of Results; Retinal Ganglion Cells/*cytology; Tomography, Optical Coherence/*methods
- From:Korean Journal of Ophthalmology 2012;26(1):32-38
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: To evaluate the effect of the scanning laser ophthalmoscope (SLO) guided re-test mode on short- and long-term measurement variability of peripapillary retinal nerve fiber layer (RNFL) thickness obtained by spectral domain-SLO optical coherence tomography (SD-SLO/OCT). METHODS: Seventy five healthy eyes were scanned 3 times per day (intra-session variability) by both the SLO guided re-test mode and the independent mode of SD-SLO/OCT. Subjects were scanned 3 times by both modes at visits within a 2-week interval (inter-session variability). For testing longitudinal variability, 3 separate exams were performed over 6 months by both modes. The coefficient of variation (CV), reproducibility coefficient (RC) and intraclass correlation coefficient of RNFL thickness were compared between the two modes. RESULTS: The intra-session RC and CV ranged from 5.4 to 12.9 microns and 1.76% to 5.72% when measured by independent mode and 5.4 to 12.5 microns and 1.75% to 5.58% by re-test mode, respectively. The inter-session RC and CV ranged from 5.8 to 13.3 microns and 1.89% to 5.78% by independent mode and 5.8 to 12.7 microns and 1.90% to 5.54% by re-test mode, respectively. Intra-session and inter-session variability measurements were not significantly different between the two modes. The longitudinal RC and CV ranged from 8.5 to 19.2 microns and 2.79% to 7.08% by independent mode and 7.5 to 14.4 microns and 2.33% to 6.22% by re-test mode, respectively. Longitudinal measurement variability was significantly lower when measured by the re-test mode compared to the independent mode (average, p = 0.011). CONCLUSIONS: The SLO guided re-test mode for RNFL thickness measurement in SD-SLO/OCT employing a tracking system improved long-term reproducibility by reducing variability induced by inconsistent scan circle placement.
