Driving with glaucoma? Some patients increase scanning to adapt for impaired vision

Some people with glaucoma-related binocular (both eyes) vision loss can pass a standard driving test by adopting increased visual scanning behavior, reports a study in the October issue of Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Wolters Kluwer.
Increased scanning–particularly more frequent head and eye movements–was a key strategy to compensate for visual impairment due to glaucoma, reports the study by Enkelejda Kasneci, PhD, of University of Tübingen, Germany, and colleagues. “Like most people, many glaucoma patients with simulated driving test loss can make useful adaptations for their condition,” comments Anthony Adams, OD, PhD, Editor-in-Chief of Optometry and Vision Science.
Drivers with Glaucoma Adapt by Moving Their Eyes and Head
In a state-of-the-art virtual reality driving simulator at a Mercedes-Benz technology center, six patients with glaucoma and binocular vision loss performed a simulated driving test. With real acceleration, 360-degree visual projection, and a real car body, the moving-base simulator provided a “close-to-realistic driving experience.”
During the 40-minute test, drivers encountered various traffic situations and nine different hazardous situations–for example, pedestrians suddenly appearing behind parked cars or risky passing maneuvers by oncoming cars. Subjects who failed any of the nine hazardous situations failed the driving test.
Eight subjects with normal vision were studied for comparison. In both groups, sophisticated measures of the subjects’ eye- and head-tracking movements were obtained and compared with performance on the driving simulation.
Three of the six glaucoma patients passed the driving test, with performance indistinguishable from that in subjects with normal vision. Compared to patients who failed, passing drivers showed “increased visual exploration”–they made more head movements and more eye movements……….
Read more: http://www.eurekalert.org/pub_releases/2015-10/wkh-dwg102715.php
Source: EurekAlert