Background
The aim was to compare the ability of confocal scanning laser ophthalmoscopy (CSLO), scanning laser polarimetry (SLP), and
optical coherence tomography (OCT) to discriminate eyes with ocular hypertension (OHT), glaucoma-suspect eyes (GS) or early
glaucomatous eyes (EG) from normal eyes.
Methods
Ocular hypertension, GS, and EG were defined as normal disc with intraocular pressure >21 mmHg, glaucomatous disc without
visual field loss, and glaucomatous disc accompanying the early glaucomatous visual filed loss respectively. Ninety-three
normal eyes, 26 OHT, 55 GS, and 67 EG were enrolled. Optic disc configuration was analyzed by CSLO (version 3.04), whereas
retinal nerve fiber layer thickness was analyzed by SLP (GDx-VCC; version 5.3.2) and OCT-1 (version A6X1) in each individual.
The measurements were compared in the four groups of patients. Receiver operating characteristic curve (ROC) and area under
the curve (AUC) discriminating OHT, GS or EG from normal eyes were compared for the three instruments.
Results
Most parameters in GS and EG eyes showed significant differences compared with normal eyes. However, there were few significant
differences between normal and OHT eyes. No significant differences were observed in AUCs between SLP and OCT. In EG eyes,
the greatest AUC parameter in OCT (inferior—120; 0.932) had a higher AUC than that in CSLO (vertical cup/disc ratio; 0.845;
P=0.017). In GS, the greatest AUC parameter in OCT (average retinal nerve fiber layer [RNFL] thickness; 0.869; P=0.002) and SLP (nerve fiber indicator [NFI]; 0.875; P=0.002) had higher AUC than that in CSLO (vertical cup/disc ratio; 0.720).
Conclusions
Three instruments were useful in identifying GS and EG eyes. For glaucomatous eyes with or without early visual field defects,
SLP and OCT performed similarly or had better discriminating abilities compared with CSLO.
Keywords Glaucoma - Optical coherence tomography - Scanning laser polarimetry - Confocal scanning laser ophthalmoscopy - Early stage