In a recent driving simulation, people with advanced glaucoma had twice as many accidents as those with normal vision.
The study, conducted at Tohoku University Graduate School of Medicine in Sendai, Japan, matched two 36-person groups for age, driving experience and more.
The most common type of accident for both was a collision with a child, car or other object that entered the scene suddenly from the side. But the drivers with glaucoma had more than twice as many collisions as the normal-vision drivers.
The problem is that glaucoma can reduce peripheral vision, whether partially or severely, without harming central vision. People with advanced glaucoma often pass the visual acuity test given in most countries and in most of the United States, because it checks only straight-ahead distance vision.
A visual fields test could prevent those with severe peripheral vision loss from renewing their license. Or it could trigger a requirement for special mirrors to be installed on their vehicles, to help them overcome their side vision loss.