Predicting Driving Performance using the Performance-Centered Portable Test (PERCEPT) in Patients with Glaucoma

Abstract

Purpose : The Performance-Centered Portable Test (PERCEPT) is a portable visual performance test investigating spatiotemporal and attentional mechanisms relevant to vision. The purpose of this study was to evaluate the ability of PERCEPT and standard automated perimetry (SAP) to predict simulated driving performance in patients with glaucoma.

Methods : This was a cross-sectional study involving 36 patients with bilateral glaucomatous visual field loss and 27 control healthy subjects. All subjects had SAP, driving simulation, and PERCEPT evaluation. The PERCEPT task consists in recognizing the orientation of a central tumbling E while also simultaneously identifying the position of a peripheral Gabor patch. The duration of stimulus presentation is progressively decreased until a reliable threshold for task performance can be obtained. Driving performance was evaluated on a driving simulator with curve negotiation and car following tasks. A summary index of driving performance was extracted through principal component analysis of simulator data. Linear regression models were used to evaluate the association between results from PERCEPT and objective driving performance and adjust for confounding variables.

Results : Mean age in the glaucoma and control groups was 68.3 ± 9.1 years vs. 55.5 ± 14.8 years, respectively (P<0.001). Average SAP mean deviation of the better and worse eye of glaucoma patients were -5.1 ± 7.1 dB and -9.1 ± 7.3 dB, respectively. PERCEPT processing speed was significantly higher (worse) in glaucoma patients compared to controls (688.1 ± 712.0 ms vs. 149.6 ± 303.6 ms, respectively; P<0.001). Simulated driving performance was significantly worse in glaucoma patients than controls (0.86 ± 3.38 vs. -0.89 ± 2.00; P=0.020). PERCEPT was more strongly associated with simulated driving performance (R²=35%; P<0.001) than SAP binocular MS (R²=20%; P<0.001). In a multivariable model adjusting for age, gender, and SAP binocular MS, PERCEPT processing speed was still significantly predictive of simulated driving performance (P=0.002).

Conclusions : PERCEPT was significantly predictive of driving performance as assessed on a driving simulator, providing additional information besides standard perimetry in predicting performance. These findings suggest that PERCEPT could be an effective test for evaluating functional performance in patients with glaucoma.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.