RESUMO
Purpose. To investigate the diagnostic accuracy of machine learning classifiers (MLCs) using retinal nerve fiber layer (RNFL) and optic nerve (ON) parameters obtained with spectral domain optical coherence tomography (SD-OCT). Methods. Fifty-seven patients with early to moderate primary open angle glaucoma and 46 healthy patients were recruited. All 103 patients underwent a complete ophthalmological examination, achromatic standard automated perimetry, and imaging with SD-OCT. Receiver operating characteristic (ROC) curves were built for RNFL and ON parameters. Ten MLCs were tested. Areas under ROC curves (aROCs) obtained for each SD-OCT parameter and MLC were compared. Results. The mean age was 56.5 ± 8.9 years for healthy individuals and 59.9 ± 9.0 years for glaucoma patients (P = 0.054). Mean deviation values were -1.4 dB for healthy individuals and -4.0 dB for glaucoma patients (P < 0.001). SD-OCT parameters with the greatest aROCs were cup/disc area ratio (0.846) and average cup/disc (0.843). aROCs obtained with classifiers varied from 0.687 (CTREE) to 0.877 (RAN). The aROC obtained with RAN (0.877) was not significantly different from the aROC obtained with the best single SD-OCT parameter (0.846) (P = 0.542). Conclusion. MLCs showed good accuracy but did not improve the sensitivity and specificity of SD-OCT for the diagnosis of glaucoma.
RESUMO
PURPOSE: To evaluate the intrasession, intersession, and interexaminer variabilities of retinal nerve fiber layer measurements (RNFL) with spectral-domain optical coherence tomography (OCT). METHODS: A total of 32 healthy individuals and 34 patients with chronic glaucoma underwent RNFL measurements with the Cirrus HD-OCT Model 4000 (Carl Zeiss Meditec, Dublin, CA, USA) 5 times during the same sitting by one examiner to assess intrasession variability. The same examiner performed RNFL measurements in the same patients on 5 different days to assess intersession variability. A second examiner performed RNFL measurements in the same patients to assess interexaminer variability. The coefficients of variation and intraclass correlation coefficients were obtained for the following parameters: average thickness, quadrant thickness, and Clock hour thickness measurements. RESULTS: Intrasession variability: In patients with glaucoma, coefficients of variation ranged from 4.51% to 11.84%. Intraclass correlation coefficients ranged from 0.74 to 0.99. In healthy individuals, coefficients of variation ranged from 2.92% to 6.99%. Intraclass correlation coefficients ranged from 0.89 to 0.98. Intersession variability: In patients with glaucoma, coefficients of variation ranged from 3.68% to 10.50%. Intraclass correlation coefficients ranged from 0.82 to 0.99. In healthy individuals, coefficients of variation ranged from 3.13% to 6.92%. Intraclass correlation coefficients ranged from 0.87 to 0.99. Interexaminer variability: In patients with glaucoma, coefficients of variation ranged from 2.62% to 14.94%. Intraclass correlation coefficients ranged from 0.55 to 0.98. In healthy individuals, coefficients of variation ranged from 2.04% to 7.31%. Intraclass correlation coefficients ranged from 0.86 to 0.98. CONCLUSIONS: These findings indicate that RNFL measurements with spectral-domain OCT display excellent reproducibility, with low intrasession, intersession, and interexaminer variabilities.