MONDAY, Nov. 12 (HealthDay News) -- Drivers with vision loss caused by advanced glaucoma had twice as many vehicle crashes as people with normal vision when using a driving simulator, according to a small, new study.

Glaucoma is an age-related eye disease that affects peripheral vision. Drivers need good peripheral vision to keep up with traffic, stay in the correct lane, and see stop lights, vehicles and pedestrians, the researchers noted.

The findings from the study -- which included 36 people with advanced glaucoma and 36 people with normal vision -- suggest that people who want to obtain or renew a driving license should have to pass a visual field test to ensure they have adequate peripheral vision, the researchers said.

The study was presented Sunday at the annual meeting of the American Academy of Ophthalmology in Chicago.

"To help ensure everyone's safety on our roadways, we would like to create mandatory vision-testing guidelines for glaucoma patients," lead researcher Dr. Shiho Kunimatsu-Sanuki, of the Tohoku University Graduate School of Medicine in Sendai, Japan, said in an academy news release. "We now know that integrating the visual field test into the requirements for a driver's license could save lives."

With proper care, many people with glaucoma can maintain a level of vision that would enable them to drive safely.

In the United States, visual field requirements for drivers vary from state to state. Twelve jurisdictions restrict licenses for people with visual impairments, and some states or territories require these drivers to install additional mirrors on their vehicles.

More than 2.7 million Americans aged 40 and older have glaucoma, which is the second leading cause of blindness worldwide, the news release noted.

Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

More information

The U.S. National Eye Institute has more about glaucoma.