Purpose: To evaluate and compare the diagnostic specificities of peripapillary retinal nerve fiber layer (RNFL) thickness, macular ganglion cell-inner plexiform layer (GC-IPL) thickness, and optic nerve head (ONH) measurements in nonglaucomatous myopic individuals.
Methods: In a prospective, cross-sectional study, participants underwent a complete ophthalmic examination, a screening automated visual field test, and axial length measurement. The study eye then underwent optic nerve head and macular scanning using spectral-domain optical coherence tomography (OCT) instrumentation to determine RNFL thickness, GC-IPL thickness, and ONH measurements. False-positive rates for each of the OCTderived parameters, using predefined criteria for an abnormal test, were calculated. Comparative analysis was performed using the McNemar test.
Results: Data from 43 eligible subjects were analyzed. The mean age was 30±6.8 years (range, 22 to 50 y) with an average axial length of 25.26±1.21mm (range, 23.06 to 29.07mm) and mean spherical equivalent of -4.50±1.93D (range, -1.00 to -9.00 D). The falsepositive rate was higher when using RNFL parameters compared with both ONH (47% vs. 7%, respectively; P<0.001) and GC-IPL (47% vs. 26%, respectively; P=0.049) parameters. The false-positive rate was higher when using GC-IPL parameters, compared with ONH parameters (26% vs. 7%, respectively; P=0.039).
Conclusions: Caution should be exercised when relying on OCTderived RNFL and GC-IPL thickness values to diagnose glaucoma in myopic individuals. OCT-derived ONH parameters perform better than RNFL and GC-IPL parameters and may increase diagnostic specificity in this population.
- Ganglion cell
- Optic nerve
- Optical coherence tomography
- Retinal nerve fiber layer
ASJC Scopus subject areas