Monocular Vision: Etiology, Symptoms and Rehabilitation
There are a variety of reasons why a person can develop sudden visual loss, including inflammation, vasculitis, trauma and mechanical dysfunction. However, the most common cause is ocular infarction—ischemic damage to the eye—that results in permanent vision loss.
The main consequences of this – monocular vision – are lack of depth perception and restricted peripheral vision in one eye. With the absence of this visual information, individuals will have difficulty in many aspects of his or her daily functioning, including walking and reading, and consequently will need to pay close attention to accomplish these tasks. For example, walking down stairs becomes difficult because these patients cannot determine how far down the stairs go. In addition, they might find it hard to locate new objects or even to pour a cup of water.
Inna Babaeva, OTR/L, an Occupational Therapist at Lighthouse Guild’s Healthcare Center, says “The reason that I decided to concentrate in this area is because therapy can really benefit and help patients a lot with their daily lives and functions, and can restore their safety and mobility. My goal is to make patients more functionally independent.”
There are several occupational therapy interventions that can help someone with Monocular Vision, including compensatory strategies for depth perception loss, activities for visual motor coordination that help to regain cues to depth and relearn through experience, and visual retraining to understand spatial relationships of stationary and moving objects in relation to one another. Another option is visual skills training, such as fixation, scanning, pursuit and saccades—in essence, learning how to compensate for lost visual field.
The first step in therapy, according to Ms. Babaeva, is to talk to the patients and make them aware of their limitations.
“You have to educate them about their situation, and they need strategies in terms of safety,” she said. “They need to do exercises for visual skills training and work on visual motor skills to help them to compensate for depth perception loss. The more they practice the suggested exercises the more they are able to evaluate their environment correctly.”
Going through rehabilitation and consistently practicing these exercises can really improve their visual function and can enable these patients to live normal lives, says Ms. Babaeva.
The idea of training is based on the concept of neuroplasticity. “We hope that patients will be able to retrain their brain to understand the space around them under changed visual abilities. This can be tough,” says Ms. Babaeva, “but it’s not impossible, and once achieved can really help patients to improve their functional independence.”