Macular retinal dystrophy is a rare genetic eye disorder that causes vision loss. Macular retinal dystrophy affects the back of your eye, or retina. It leads to cell damage in an area called the macula, which controls how you see what’s out in front of you. When it happens, you have trouble seeing straight ahead. This makes it tough to read, drive, or do other daily activities that require you to look straight ahead.
It’s caused by a pigment that builds up in the macula’s cells. Over time, this substance can damage cells that play a key role in clear central vision. Your sight gets blurry or warped. But your side, or peripheral, vision isn’t harmed. So you won’t be totally blind.
Macular corneal dystrophy, is an unrelated and separate, rare genetic condition, affects the cornea, the transparent layer on the front of the eye. Cloudy areas form on the cornea, leading to severe visual impairment, usually when a person is in their 50s.
Who Gets It?
There are two types of macular retinal dystrophy. A form called Best disease usually appears in childhood and causes different amounts of vision loss. The second usually affects you in mid-adulthood. It causes vision loss that slowly gets worse.
People with Best disease usually have a parent who has it. Parents pass the gene on to their children.
It’s less clear how adult-onset macular retinal dystrophy is passed from parent to child. You may not have any other family members with the condition.
What Causes It?
Changes in your genes (your doctor will call these genetic mutations) are to blame. Some people have two specific genes that are affected.
Changes in the BEST1 gene cause Best disease and sometimes adult-onset macular retinal dystrophy. Mutations in the PRPH2 gene cause adult-onset macular retinal dystrophy. However, it’s hard to tell which gene is affected. That means the exact cause is unknown.
We don’t know how these gene changes cause pigment buildup in the macula. Doctors also don’t know why only central vision is harmed.
How Is It Treated?
There’s no effective treatment for this condition. Vision loss usually develops slowly over time. There’s new research that involves the use of stem cells.