The type of homonymous visual field loss in stroke patients may not be as useful of a tool to assess driving ability as a standardized driving simulator. Photo: Mohammad Rafieetary, OD. Click image to enlarge.

Visual field loss, a common side effect of stroke, often limits an individual’s ability to drive. In a recent study, data showed that the type of homonymous visual field loss could not predict driver safety. The findings also demonstrated the potential of a standardized driving simulator test to assess an individual’s ability to drive.

In this cross-sectional analysis, researchers retrospectively compared data on performance and safety from a traffic simulator test for 153 participants with withdrawn driver’s licenses due to visual field loss from stroke and 83 healthy individuals without visual deficits. A national accident database was then used to follow 93 individuals in the stroke group who had regained their driver’s license after a successful simulator test.

The study found that 65% of participants in the stroke cohort passed the simulator test and that younger patients were more successful than their older counterparts. However, the study authors observed that type of homonymous visual field loss and side of visual field loss were not predictors of driver safety. They reported that none of the participants who regained their licenses were involved in motor vehicle accidents three to six years after the test.

“In this large cohort, driver safety could not be predicted from the type of homonymous visual field loss. Even individuals with severe visual field loss might be safe drivers,” the study authors concluded in their paper. “Therefore, it seems reasonable to provide an opportunity for individualized assessments of practical fitness to drive in circumstances of licensing issues.”

A standardized driving simulator could be a useful tool when assessing an individual’s driving fitness, according to the study authors, who also noted that the optimal cut-off level for such a test remains unknown.

Bro T, Andersson J. The effects of visual field loss from stroke on performance in a driving simulator. Optom Vis Sci. August 1, 2022. [Epub ahead of print].