Glaucoma patients pose crash risk, despite passing eye test

Researchers from Wills Eye Hospital (WEH) in Philadelphia examined the crash rate of glaucoma patients by following 161 people – with an average age of 64  – over four years with moderate open angle glaucoma in at least one eye.The study evaluated several aspects of vision including visual acuity, peripheral vision and contrast sensitivity.It also considered patients’ ability to conduct normal daily activities, such as reading street signs and finding objects on a crowded shelf. Each year, patients were asked if they were, as a driver, involved in a vehicle accident the previous year.{{quote-A:R-W:400-I:2-Q:“What we found was between 5% and 10% of these glaucoma patients were involved in motor vehicle accidents each year despite still having vision good enough to legally qualify for driving”-who:Dr Jonathan Myers, Wills Eye Hospital}}“What we found was between 5% and 10% of these glaucoma patients were involved in motor vehicle accidents each year despite still having vision good enough to legally qualify for driving,” study researcher and WEH glaucoma service chief Dr Jonathan Myers said.According to the research, this compares to a 1.1% crash rate for drivers of a similar age – 61-65 years old – as reported in 2017 Pennsylvania Crash Facts.Myers added: “Interestingly, one standout finding was that peripheral vision in the worst eye made the biggest difference. That suggests that in some study patients, significant blind spots existed which could have been a liability for driving.”For most US states, the legal vision requirents for driving are 20/40 for night and 20/70 for daytime driving, although daytime driving thresholds vary. Some states also require between 120 and 140 degrees of side-to-side vision.Myers said the study highlighted “a very common predicament” for eye doctors and families to consider, as many countries grapple with aging populations.“It’s increasingly common to address driving with families. Driving isn’t simply about driving, it’s also about independence for an aging population so these can be very difficult and otional conversations. As doctors, we need to care for the whole patient and be part of the care team with the family,” he said.In Australia, glaucoma is now one of the most common reasons for driving cessation, with a 3.6 times increased crash risk, largely connected to visual field loss.In closed-road circuit testing, glaucoma patients required twice the number of driving instructor interventions than control patients did, with the greatest probls being drifting out of lanes and issues with traffic lights. More reading:Drawing a line on driving standards