Vision Training May Help Patients With Glaucoma See Better

Larry Hand

February 11, 2014

Computer-based vision training may improve vision for patients with glaucoma, possibly because of plasticity in the retina and vision-related areas of the brain, according to an article published online February 6 in JAMA Ophthalmology.

Bernhard A. Sabel, PhD, and Julia Gudlin, PhD, from the Institute of Medical Psychology, Medical Faculty, Otto-von-Guericke University of Magdeburg, Germany, analyzed the results of a prospective, double-blind, randomized, placebo-controlled trial conducted between March 2004 and August 2007.

The trial involved 30 patients with glaucoma randomly assigned either to vision restoration training for glaucoma (gVRT) or to placebo (n = 15 each). Two patients in each group were lost to follow-up.

Of 14 men and 16 women aged 39 to 79 years, 20 had primary chronic open-angle glaucoma, 5 had normal-tension glaucoma, 1 had angle-closure glaucoma, and 4 had secondary glaucoma. No significant differences existed at baseline for age, time of first diagnosis, or intraocular pressure and visual acuity. Both eyes were affected in 26 patients.

Using computer-based high-resolution perimetry (HRP), the researchers measured natural visual field variability for 2 days before training began. They also used an eye tracker to measure eye movements during HRP to determine fixation stability before and after training.

Training

The gVRT group completed computer-based training, consisting of a classic vision restoration training variant developed in the 1990s at Magdeburg. Responding to luminance increment stimuli, patients pressed the spacebar when they detected a stimulus. Researchers adapted parameters on a monthly basis for levels of difficulty.

The training "can be used for the round-shaped visual field loss found in glaucoma patients," Dr. Sabel told Medscape Medical News. He said his group is in the process of offering the training for anyone to use.

For the placebo group, training consisted of using a line segment bar, always presented within the central visual field in 1 of 4 random orientations, which patients could identify by pressing a key.

Patients trained 6 days a week for 3 months, for 30 minutes twice a day, using commercially available personal computers with adaptive adjustments online. Seventeen patients trained with the right eye and 13 with the left.

Detection Rate and Reaction Time

For patients in the gVRT group, the mean HRP detection rate significantly increased, going from 37.45 detections (SD, 21.85) at baseline to 44.17 (SD, 24.39) after gVRT (P = .007) compared with a nonsignificant increase from 38.69 (SD, 27.03) to 39.84 (SD, 29.15) for the placebo group (P = .48).

As a control, researchers measured detection changes in nontrained eyes but found no significant changes for either group.

The gVRT group also showed significant increases in HRP reaction time, with mean values improving from 579.73 (SD, 72.97) milliseconds at baseline to 541.67 (SD, 74.78) milliseconds after training (P = .009) compared with a change from 558.53 (SD, 71.28) milliseconds to 559.53 (SD, 61.1) milliseconds for the placebo group (P > 99).

The gVRT group also showed improvements in visual field tests for white-on-white and blue-on-yellow perimetry.

Clinically Useful

The researchers conclude that their finding is clinically useful. "Whatever the mechanism, we can now be more optimistic that the course of vision loss in glaucoma is not simply pointed downhill but has considerable uphill potential. This new understanding justifies additional research and provides evidence to support routine use of gVRT in the clinical setting."

"It is important to understand that the disease as such is not influenced by the training, but the training improves the way the brain processes information," Dr. Sabel told Medscape Medical News. "The brain's intelligence to compensate damage, called plasticity, together with an intelligent, game-like computer program, is what does the trick."

He wrote that he was actually surprised at the high degree of improvement, "given that the lesion is so peripheral in the eye."

A Step Forward

"This was the first promise, I think, of perhaps actually improving the current way that people are perceiving vision once they've lost some from glaucoma," Shuchi Patel, MD, assistant professor of ophthalmology at Loyola University Stritch School of Medicine in Maywood, Illinois, and a glaucoma expert, told Medscape Medical News.

"Everyone's been focusing more on trying to slow the progression of glaucoma or look for nerve regeneration to cure glaucoma, but not as many people are focusing on what we can do to visually rehabilitate people who already have glaucoma or vision loss from it," she continued. "I thought this was a very interesting approach to glaucoma and its treatment. Until we do come up with ways to reverse vision loss, even the best we're going to be able to do is keep people at a standstill."

Getting the vision testing into widespread use, however, would take a great effort, she said. "It did sound like quite a time commitment, and so I feel you'd just have to have a very motivated patient. All the patients in their study were well-controlled patients who did not need surgical intervention and were patients who could do visual training."

Although the results from their tests were promising, patients did not necessarily report improvements in quality-of-life questionnaire answers also done as part of the study, she added.

"They explained that in the paper that possibly because, even pretreatment, they were not at a place where they felt significantly vision-impaired...the slight amount of improvement was not enough to make them notice a big difference functionally," Dr. Patel said. "But I think if you are asking for an hour commitment of your day for a long period of time, and patients are not noticing a significant improvement in their function, then compliance is going to be an issue."

This research was funded by NovaVision Inc, Braingames Online GmbH, and a predoctoral fellowship of the University of Magdeburg. The authors and Dr. Patel have disclosed no relevant financial relationships.

JAMA Ophthalmol. Published online February 6, 2014. Abstract

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