vision rehabilitation

Neuro-Optometric Rehabilitation: A Specialty Worth Examining

A leader in the field explains the role of vision rehabilitation in physically challenged people.

BY LESLIE GOLDBERG, Associate Editor

Vision is the process of deriving meaning from what is seen. When a patient has a traumatic brain injury or suffers from stroke, autism, multiple sclerosis or cerebral palsy he will often have a visual processing problem and experience what William V. Padula, O.D., FAAO, FNOR, DPNAP calls "a spatial collapse." The job of a neurooptometrist is to assess the way the brain processes information sent by the eyes and provide rehabilitation of these visual, perceptual and motor disorders.

Dr. Padula, of the Padula Institute of Vision, in Guilford, Conn., is a pioneer in the field of neurooptometric rehabilitation. He treats patients who require treatment for symptoms that include focusing problems, double vision, dizziness or imbalance. Dr. Padula says that there are nearly 50 million people in the United States with a neurological problem and that many of these individuals have a visual processing problem. "That's why neurooptometric rehabilitation is a prime area for specialty within optometry," he says.

The patient is an ex-Marine who has had a TBI. He is suspended by the LiteGait (Mobility Research) to support him to walk on a weight-bearing pressure sensitive treadmill. Dr. Padula is using this device to measure and treat Visual Midline Shift Syndrome.

The Founding of Neuro-Optometric Rehabilitation

Dr. Padula, who has been a practicing optometrist for more than 30 years, chose to do his residency in vision development of children because he had an interest in working in low-vision. During his residency, he donated time at the local Easter Seals, treating physically challenged children. When he left the institute, he maintained a relationship with the organization and set up the first not-for-profit clinic in Connecticut.

He thought this would be a low vision clinic, but with his Easter Seals' patients the primary issue he saw was physical disability from cerebral palsy, Parkinson's disease, and traumatic brain injury, so his patients had a wide variety of issues.

"As I worked with each impaired person, it became clear to me rather quickly that these people had a very different need," says Dr. Padula. "The issues they had were 'How am I going to balance better?' and 'How am I going to walk?' They were having difficulty talking about their spatial environment." Up to this point, ophthalmologists and optometrists treating physically challenged people looked at the health of the eye, but did not address the greater issues, says Dr. Padula.

"I would speak to my wife about what I was encountering and she finally asked if I had spoken to anyone else about my findings. I said 'no' and she recommended that I contact the other six or seven optometrists who were working in this field and meet with them." In 1989, these optometrists, spread all over the country, met in Chicago to compare notes. They found some common ground and some differences. "We continued to meet and other doctors wanted to join our group, which we were not in favor of at first, but eventually we realized the importance of collaborating and this led to the development of the Neuro-Optometric Rehabilitation Association (NORA)."

A New Way of Treating Patients

"I began to work with patients using new approaches — lenses and prisms, sectoral and partial occlusion and saw immediate results," says Dr. Padula. The founding president of NORA began to see more and more neurologically challenged children and adults. It became a major part of his practice and patients began traveling great distances to see him. Dr. Padula is quick to explain that neurooptometric rehabilitation is not vision therapy, but a whole new specialty area in optometry. "It is a vision-processing problem in the brain. When I began to realize this, I changed my approach and began to work with visual processing," he says.

Two Visual Processing Systems

Dr. Padula works with brain processing dysfunctions using lenses, prisms and special techniques to reorganize one of two visual processing systems. "This is not a long-term approach," explains. "It is a paradigm shift — a whole new approach for dealing with visual problems for the neurologically-challenged population."

There are two visual processing systems: the focal system, which Dr. Padula says is related to attention and concentration and is used for identification. "It is related to higher cognitive processing and higher order perception, but is not the first visual system that you are born with," he explains. The second is the ambient visual process, which is the first visual system that you are born with. "This is a spatial visual process," says Dr. Padula. "It is delivered primarily from the peripheral part of the eyes and it sends information to the mid-brain to match up with sensorimotor information. This part of the system is preconscious." He explains that the ambient visual process sends information to probably 99% of the cerebral cortex to preprogram spatial information. "If that system is not there, all you have is a focal process," says Dr. Padula. "If you don't have the preconscious system working for you, the whole system jams and you have spatial collapse. This is what happens following a brain injury."

In research that he published in the Journal of Brain Injury in 1994,¹ Dr. Padula demonstrated through use of visual evoked potentials (VEP) that following a brain injury there is a spatial collapse. "The ambient system collapses, leaving the person over-focalized. We termed this syndrome Post-Trauma Vision Syndrome," he says. "Once a patient has the collapse, the eye muscle problems begin. Before we recognized this, optometrists treated patients with vision therapy."

Dr. Padula now recognizes this as an embedding problem. He treats Post-Trauma Vision Syndrome with low amounts of prism and bi-nasal occlusion will get an immediate change in the VEP amplitude. "This demonstrates that you are re-establishing the spatial visual system," says Dr. Padula. "We found almost immediate improvement with convergence, focusing and attention as the ambient system began to support the higher visual process."

Another Piece of the Puzzle

Dr. Padula explains that there is a second component to this collapse of the ambient visual process. "If you have a patient who has had a stroke or brain trauma, their concept of mid-line — or how the body moves laterally, anteriorly and posteriorly becomes distorted, so the body has trouble remaining upright against gravity. In a moment's time, information is sent from one side of the body differently than to the other. The ambient process steps in and changes the space. It expands size on one side and takes it away from the other — it pulls the mid-line away from the paralyzed side."

Dr. Padula explains that when you watch this physically challenged person walk, they will be leaning away from the paralyzed side. "For years, I would ask neurologists why this was and they would say it must be neurological. Well it is, but it happens to be a (neurological) vision processing dysfunction. When the ambient system pushes the midline off to the side, part of the brain is literally thinking that the floor is tilted," he says.

When Dr. Padula realized this, he used two prisms facing in the same direction (a yoked prism) and gave them to the person with the stroke. The patient began to weight-bear immediately. This has been termed Visual Midline Shift Syndrome.

The Movement to Acceptance

Dr Padula has spent the last 8 years doing research on visual midline shift syndrome and his research was just accepted by the Journal of Brain Injury. It will be published in the next year. He says that neurooptometric rehabilitation is now more widely known in other professions.

"We have published more in the neurology journals than in our own field," says Dr. Padula. "Optometry has oriented more to vision therapy — but this is a paradigm shift. This shift will encompass an interdisciplinary model for optometry."

Dr. Padula is beginning to see a shift in this belief. The AOA House of Delegates recently approved the change of name for the Low Vision Rehabilitation Section to the Vision Rehabilitation Section (VRS). This was done to enable neuro-optometric rehabilitation for neurologically challenged persons to become part of the VRS plan for the AOA.

"The wheels are starting to turn, but it's taken 20 years," says Dr. Padula. "We need board certification in this specialty in order to move forward in today's healthcare system." OM

1. Padula W, Argyris S, Ray J. Visual evoked potentials evaluating treatment for post-trauma vision syndrome in patients with traumatic injuries. Brain Injury 1994;8:125-133.