Abstract
Purpose: :
To compare the accuracy of the PERG to that of standard automated perimetry (SAP), short-wavelength automated perimetry (SWAP) and frequency-doubling technology perimetry (FDT) for discriminating between healthy eyes and those with glaucomatous optic neuropathy (GON).
Methods: :
83 eyes of 42 healthy recruits (with normal appearing optic discs by clinical examination and masked stereophotograph assessment) and 93 eyes of 54 glaucoma patients (with glaucomatous appearing optic discs by masked stereophotograph assessment; SAP MD = -1.39 dB, 95% CI = -2.95, -1.30) from the UCSD Diagnostic Innovations in Glaucoma Study (DIGS) were tested with PERG (Glaid PERGLA, Lace Elettronica, Rome, Italy), SAP, SWAP, and FDT within 9 months. Dependent variables were PERG amplitude (µV) and both mean deviation (MD in dB) and pattern standard deviation (PSD in dB) for all psychophysical tests. ROC curve analyses were used to describe the diagnostic accuracy of each variable.
Results: :
At the time of PERG testing, patients were significantly older than healthy participants by 6 years (68.8 years and 63.3 years, respectively; p = 0.02) and IOP was similar between GON eyes and healthy eyes (15.0 mmHg and 14.2 mmHg, p = 0.52). All dependent variables were significantly different between groups (p ≤ 0.001) except SWAP MD (p = 0.06). The ROC curve area for PERG amplitude was 0.74 (0.67, 0.82). ROC curves areas for MD and PSD were 0.79 (0.72, 0.85) and 0.79 (0.72, 0.85) respectively, for SAP; 0.57 (0.49, 0.66; chance discrimination likely due to mild cataract in some eyes) and 0.73 (0.66, 0.81) respectively, for SWAP; and 0.79 (0.72, 0.85) and 0.82 (0.76, 0.88) respectively, for FDT.
Keywords: electrophysiology: clinical • visual fields • perimetry