Retinitis pigmentosa (RP) is a group of rare, genetic disorders that cause a breakdown and loss of cells in the retina. The disorder affects 1 in 4000 people worldwide. Retinitis pigmentosa is caused by genetic mutations and harmful changes to any one of more than 50 genes that are responsible for the process of making proteins that are needed in the cells of the retina. The retina is the light sensitive tissue that lines the back of the eye. Common symptoms include difficulty seeing in dim light and at night and a loss of peripheral vision or narrowing of the field of vision. This has also been described as tunnel vision.
Symptoms typically begin in late childhood with difficulty getting around in the dark and slow adjustment to changes in lighting. Field loss may not be noticeable at first but certain behavioral signs can indicate the onset of field loss. The progression of loss of vision can vary greatly from person to person.
Eventually retinitis pigmentosa can lead to total blindness.
There is no cure for retinitis pigmentosa, but there are some treatments that professionals believe can slow the progression including Vitamin A supplements. There are also adaptive vision aids that can maximize existing vision.
A retinal implant, known as a “bionic eye,” is being used in some cases of RP. The prosthetic device does not cure the disease but can restore partial sight for individuals with RP.
It is a common misperception that RP together with a hearing loss is a result of Usher syndrome. Usher syndrome is a genetic condition (see description under Conditions Related to Deaf-Blindness) that involves hearing loss and RP. However, it is important to note that RP can happen in conjunction with a hearing loss and not be a result of Usher syndrome.
A person who is dealing primarily with RP will likely have many challenges related to mobility and completing daily or work-related tasks. Communication will be impacted because the person may not be able to access facial or body expressions, maintain eye contact or follow the social flow of a conversation with a group. When a person’s fields become severely restricted there are concerns about tripping over objects on the ground or bumping into things on the right, left or above, beyond the visual fields.
Practical Implications
Having RP along with a hearing loss can create intense challenges. A person who is hard of hearing with RP may lose access to the facial expressions or lip movements that they use to assist them in conversations. Someone who is deaf with RP may eventually need to move to tactile sign language because they can no longer see the signs. Strategies such as signing at a distance or signing in a small space may be necessary when RP progresses. At some point, many people who are deaf with RP move to tactile sign language. Sometimes this progression is slow, beginning by only using tactile sign language at night or in low lighting and then moving to full time tactile sign as needed.