At-home visual therapy system targets stroke, TBI patients
Imagine a patient with a stroke or a traumatic brain injury (TBI) getting visual stimulation by sitting in front of a screen twice a day at home. This is the concept behind Vision Restoration Therapy from NovaVision Inc.
“VRT (Vision Restoration Therapy) gives me an option for treating visual fields in patients who in the past were limited to prism glasses or other prism systems that basically shifted the images around,” Kevin M. Chauvette, OD, FCOVD, who specializes in neuro-optometric rehabilitation in Merrimack, N.H., said in an interview. “With VRT, I now have a treatment that can [partially] restore visual fields.”
Patients with neurological field loss from stroke, head injury or brain tumor may benefit from VRT. “This field loss is usually bilateral and homonymous,” Dr. Chauvette added.
VRT is cleared by the Food and Drug Administration and customized for each patient. Three in-office, field-visual tests on the VRT device are averaged to determine individual border zones, stimuli size and fixation target.
“The patient is then shipped a unit that arrives at our office,” Dr. Chauvette said. “We teach the patient how to use the device and run through one session with him or her in the office.”
Dr. Chauvette has been prescribing VRT since the beginning of the year and currently has seven patients on the program. The initial course of therapy is 6 months (two 30-minute sessions a day).
“It is recommended that patients break at least 4 to 6 hours between sessions,” Dr. Chauvette said.
Candidates must also be able to sit at a screen for the entire session and must possess adequate attention skills.
During treatment, patients stare at something similar to a computer screen, with a fixation spot in the center of the screen.
“Lights of different sizes and intensities are either moved in from where they can see into the region where they cannot see, or flashed right at the border of their seeing and non-seeing areas,” Dr. Chauvette said.
Patients push a mouse button when they detect a flashing light or the center light changes color. “By constant repeated stimulation of that border zone, patients are able to detect light where they could not before,” Dr. Chauvette said. “When the border zone shifts over slightly, the patient’s field is opened up a little bit.”
NovaVision (Boca Raton, Fla.) tracks the patient’s visual progress remotely at the patient’s home via a telephone line and redesigns the parameters once a month. “Revised therapy is based on that new border zone, which might be 1º or 2º from the left of where it started,” said Dr. Chauvette, who receives a monthly patient report from NovaVision.
In a recent study of NovaVision VRT, Marshall and colleagues found that functional magnetic resonance imaging data showed increased activity in visual processing areas of the brain in six patients (ages 35 to 77) with bilateral homonymous hemianopia caused by stroke or traumatic brain injury. The researchers identified this enhanced activity 1 month after treatment started.
In another study, Romano and colleagues found that 70% of study patients achieved an average of 4.8º of visual field improvement after 6 months. “However, 83% of my patients have improved by at least 5º – some of whom have been on therapy for only 3 or 4 months,” Dr. Chauvette said. “Although it seems like a lot of time and effort, patients are really eager to get their vision back and become more independent.”
Two stroke patients show promise
Kauser V. Sharieff
Kauser V. Sharieff, OD, FCOVD, in private practice in Yorba Linda and Orange, Calif., has treated two patients with VRT since May. The first patient is a 65-year-old woman with right homonymous hemianopia who suffered a stroke about 1 year ago. After 1 month of VRT treatment, she had some degree of visual field improvement.
“It is not a complete recovery yet, but there is the possibility of restoration,” Dr. Sharieff told PCON.
The second patient is a woman in her mid-60s with left homonymous hemianopia from a stroke approximately 4 years ago. “This patient is doing slightly better than the first patient after 1 month because of increased compliance,” Dr. Sharieff said.
“Until now, we haven’t had a real treatment option for people with severe visual loss. We only had compensation strategies to try to help the patient minimize the impact or the effect of the loss,” said Dr. Sharieff, who treats acute neurorehabilitation patients at St. Jude Medical Center in Fullerton, Calif. “VRT offers the possibility of regaining central vision. I am also getting a few more referrals for this condition from neurologists and the rehabilitation team, including occupational therapists and physical therapists. VRT is a wonderful, concrete option. It has great potential, but the word needs to get out.”
Dr. Chauvette expects about half of his seven patients will require a second 6-month VRT module.
“VRT sets my practice apart by offering a cutting-edge technology,” he said. “It has also helped to solidify me as a specialist in my geographic area for those with field loss. We get referrals from neurologists, physiatrists and other rehab therapists. It’s rare that optometrists receive referrals from MDs, so when we do it is exciting. I’ve even gotten a referral from an ophthalmologist.”
For more information:
- Kevin M. Chauvette, OD, FCOVD, can be reached at 401 Daniel Webster Hwy., Merrimack, NH 03054; (603) 424-0404, ext. 17; fax: (603) 424-1147; e-mail: email@example.com.
- Kauser V. Sharieff, OD, FCOVD, can be reached at 17524 Yorba Linda Blvd., Yorba Linda, CA 92886; (714) 996-6210; fax: (714) 996-6212; e-mail: firstname.lastname@example.org. Dr. Sharieff has no direct financial interest in the products mentioned in this article, nor is she a paid consultant for any of the companies mentioned.
- NovaVision Inc. can be reached at 3651 FAU Blvd., Ste. 300, Boca Raton, FL 33431; (888) 205-0800; fax: (561) 620-2545; Web sites: www.novavision.com and email@example.com.
- Kasten E, Wust S, Behrens-Baumann W, Sabel BA. Computer-based training for the treatment of partial blindness. Nature Medicine. September 1998;9:1083-1087.
- Marshall RS, Ferrara JJ, Barnes A, et al. Brain activity associated with stimulation therapy of the visual borderzone in hemianopic stroke patients. Neurorehabil Neural Repair. 2007;27:in press.
- Romano JG. Visual field changes after Vision Restoration Therapy (VRT). Paper presented at: American Academy of Neurology Annual Meeting; May 2, 2007; Boston, MA.