When a driver gets into a life-threatening car wreck, temporary blindness can be one of the side-effects. The condition, known as Terson syndrome, occurs when a hemorrhage in the brain triggers a hemorrhage in the eye. Vitreous gel—clear, gooey stuff that forms between the lens and the retina—mixes with blood, preventing the retina's photoreceptor cells from sensing light signals that enter the eye. Often, the result is legal blindness.
Recovering from such traumatic incidents can take months. The longer the wait, the greater the degree of uncertainty that tends to settle in among patients. "These patients often have other issues related to brain injury, and we can't work on the eye until [they've] stabilized," said Rajendra S. Apte, a professor of ophthalmology at Washington University School of Medicine, in a press release. Apte and her team looked at 20 cases from three medical centers around the world where doctors performed a vitrectomy, a surgical procedure that involves removing the blurry vitreous gel and replacing it with a clear saline solution. Vitrectomies, it's worth mentioning, aren't new. They've been used to treat Terson syndrome in people with brain aneurysms since 1963. But the Washington University study represents the largest review to date of vitrectomies as a treatment for blindness that results from a traumatic brain injury. Before the surgery, most of the patients had 20/1290 vision, which means they must be 20 feet away to see an object that people with perfect vision can see from 1290 feet away. In almost every instance, the procedure fully restored 20/20 vision. Another significant finding was that time spent in recovery—up to three months in some cases—had no impact on the odds of success once the surgery was eventually performed. "It was important to learn how long we could wait to operate without having a negative effect on vision," Apte said. "In the majority of cases, it appears vision can be restored, even if the surgery is done several months after a traumatic brain injury."