by Iris Winston
Concern that drivers who have had laser eye surgery may have difficulty driving at night is unwarranted, according to the Canadian Opthalmolgical Society.
“Current scientific evidence does not support any contraindication to driving related to refractive surgery,” says Dr. Duncan Anderson of the Department of Opthalmology at St. Paul’s Hospital, Vancouver.
The society mentioned laser surgery as one of several possible causes of some reduction in visual acuity and contrast sensitivity in a section of the Canadian Medical Association’s “Determining Medical Fitness to Drive”, published earlier this year. (Other factors include age or cataracts.)
“The reaction was to make it sound as though this was a much bigger problem than it is,” says University of Ottawa Eye Institute Director General Dr. Bruce Jackson. “In some cases, a few patients may experience some difficulty with night vision, but it is usually related to high risk factors.”
He explains that patients with very large pupils (hyperopia) or in need of “a high degree of correction” (because of severe myopia, for instance) may notice a halo effect when driving at night after the surgery. Other patients find that the halo effect is reduced after the surgery and that their night vision improves.
The key factor, he says, is to screen patients to ensure that they are good candidates for the surgery and to explain possible results very clearly.
“Then it is their decision,” says Dr. Jackson, pointing out that most candidates for the surgery see the possibility of a slight, temporary blurring of vision at night as an acceptable trade-off to wearing glasses.
Certainly, this is the case for Calgary journalist Louis Hobson, who had laser surgery on one eye in 1992 and on his second eye earlier this year. “I do have a slight halo effect at night,” he says. “But I had a very bad astigmatism before the surgery and the halo is actually less noticeable than it was. And even if I have a slight blurring, it is a small price to pay for 20/20 vision.”
Dunrobin resident Jenefer Haynes has come to the same conclusion. She plans to have the surgery in the spring and has just completed a round of counselling, including being paired with a mentor who underwent the surgery last year.
“I am so impressed with the way I have been treated,” she says. “All my questions have been answered.”
Dr. David Edmison of the Focus Eye Centre, Ottawa, points out that “fewer than two percent of patients treated are aware of any reduction in night vision.”
“If you look at it scientifically, there can be up to 30 percent reduction in contrast acuity for up to six months (after the surgery) and a very small group of patients – perhaps one in a 1,000 take longer than that before they are back to normal,” he says. “From a practical point of view, very few patients treated are aware of any reduction.”