Patients with macular diseases experience the loss of their straight ahead vision because the macula, which is a very tiny spot near the center of the retina, has become damaged. As a result many people with advanced macular degeneration will experience what is called a central scotoma.  It may start as a smudge in the center of one’s vision and progress to a gray or black spot.  The size of the scotoma can change becoming larger as one’s AMD progresses.   However, usually the rest of the retina is undamaged and remains healthy.  Many of these patients compensate naturally for this disturbed central vision by shifting their vision slightly so that they can see things sharper and try to “look around” the scotoma.  They may not know what it is called, but these patients are using what is called the Preferred Retinal Locus (PRL).

The PRL allows a person with a damaged macula to use a different part of the retina other than the fovea or macula.  Patients who learn to use their peripheral vision, called Eccentric Viewing, are actually teaching their rod cells to take over the tasks that their now damaged cone cells use to perform.  Low vision specialist Dr. Randy Kinkade describes the PRL as “a retinal area that acts as a pseudofovea by providing better vision than the diseased fovea/macula.”

Dan Roberts, who has AMD and is the author of The First Year: Age-Related Macular Degeneration: An Essential Guide for the Newly Diagnosed explains that eccentric viewing can greatly enhance one’s detailed vision, “with proper training, concentrated practice and proper adaptations.”

Training

Low vision rehabilitation services offer training that teach a patient how to identify “the best” area of the retina to use and how to shift their visual field from straight ahead to their peripheral vision. The Trained Retinal Locus (TRL) is somewhat different from the PRL.  Trained Retinal Locus is a specific area of the retina that has been identified with the help of a low vision specialist that is more advantageous to reading.

Practice at Home

Practice and repetition are necessary to learn this new way of seeing. Low vision therapists can provide patients with assignments to use at home or one can find self-training exercises online.

Proper Adaptations

Proper adaptations consist of maximizing one’s useable vision using contrast, lighting and magnifiers. Bold, black letters on stark white background, reading magnifiers, and improved lighting combined with the use of one’s PRL or TRL greatly enhances one’s usable vision. To learn more about eccentric viewing training visit:

Self Training in Eccentric Viewing

Leslie Degner, RN, BSN

www.WebRN-MacularDegeneration.com