Abstract
Purpose :
To compare the performances of Compass Fundus Automated Perimetry (FAP) and Humphrey Field Analyzer (HFA) in glaucoma patients.
Methods :
120 experienced glaucoma patients underwent one FAP and one HFA perimetric test over the central 24° on one eye. The chosen eye and sequence were randomized and only reliable examinations were considered for analysis. Global indices of mean deviation (MD), pattern stardard deviation (PSD), Visual Field Index (VFI), and the area of absolute scotoma were compared between perimeters. A Glaucoma Staging System (GSS2) was analysed by means of k-test.
Results :
Mean sensitivity difference (FAP – HFA) was -1.0±2.81 dB (p<0.001, CI95% -1.61, -0.60 dB), MD difference was +0.27±2.84 dB (P=0.36, CI95% -5.30, 5.83 dB), PSD difference was +0.48±1.95 dB (P=0.0075, CI95% -3.37, 4.33 dB), and VFI difference was +2.4%±8.4% (P=0.003, CI95% -14.0%, +18.8% dB). Weighted kappa for GSS2 was 0.87. Locations with null sensitivity were 9.9±10.2 with FAP and 8.2±8.9 with HFA (difference of location 1.7±4.0 locations, P=0.013).
Conclusions :
Mean sensitivity with FAP is 1 dB lower than HFA, a finding due to different threshold strategies. Differences of global indices for FAP and HFA are small, which makes the two perimeters equivalent in the clinical setting. However FAP seems more severe in evaluating glaucomatous damage being absolute scotoma areas larger than with HFA. We raise the hypothesis that such difference may be the result of the active compensation of eye movements available with FAP.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.