Retinoschisis refers to the separation of the layers of the retina. The retina is the tissue inside the back of the eye that changes what you see into electrical signals that travel to the brain.
When the retina splits, tiny lumps called cysts form between the layers. These cysts damage nerves and keep light signals from reaching the brain. Damaged nerves can make your vision blurry.
There are two forms of this condition:
- Juvenile X-linked retinoschisis
- Degenerative (senile) retinoschisis
Juvenile X-Linked Retinoschisis
This rare condition, sometimes called XJR, mainly affects boys and men.
It damages an area in the middle of the retina called the macula. The macula gives you clear central vision, and lets you focus on things in front of you, like a book or computer. Sometimes the condition also can affect your side, or peripheral, vision.
Causes
XJR is caused by a change -- or mutation -- to a gene. If a girl gets the problem gene from a parent, they’ll carry the disorder but won't have symptoms. If a boy gets the gene, they’ll have the disorder.
If a mother has the gene, their female children have a 50% chance of being a carrier. Their male children have a 50% chance of having the disorder.
Men who have the gene can't pass it to their sons, but their daughters will be carriers.
Symptoms
XJR starts at birth and usually affects both eyes.
Symptoms can appear in the first few months of life. Some boys, though, aren't diagnosed until they start school and have trouble reading. Their vision often gets worse during childhood and then levels off for a while.
When a man reaches their 50s and 60s, their vision might start to worsen again. Some people lose a lot of their vision by adulthood, but it's rare for retinoschisis to cause blindness.
Other symptoms include:
- Eyes that look in different directions (strabismus)
- Poor close-up vision (farsightedness)
- Bleeding in your eye caused by damaged blood vessels
In rare cases, the retina will pull away from the eye completely. This is called retinal detachment, and it can lead to serious vision loss. People who have retinal detachment will need surgery to fix it.
Diagnosis
Your eye doctor will look for splits or tears in your retina. Tests for juvenile X-linked retinoschisis include:
- Optical coherence tomography (OCT): Light waves make pictures of the retina.
- Ultrasound: Sound waves create pictures of the eyes. This can show bleeding in the eye.
- Electroretinogram (ERG): This measures electrical activity in the retina. A special sensor is placed in each eye. While you look at a flashing light, the doctor will see how your retinas respond.
- Gene tests: These look for the RS1 gene that causes juvenile X-linked retinoschisis.
People with juvenile retinoschisis should get regular eye exams to check for vision loss.
Treatment
No medicine or surgery can treat a divided retina. Glasses can’t do much if your vision is bad because of nerve damage, but they can help if you’re nearsighted (can’t see far away) or farsighted. Large-print textbooks, computer screens, and other low-vision tools can help children in school.
Bleeding in your eye is treated with a laser or with cold (cryotherapy) to close damaged blood vessels in the retina. Surgery can fix a detached retina.
Researchers are testing new treatments for retinoschisis. One of these replaces the damaged gene with a copy of a healthy gene. Stem cell treatments are also being studied.
Degenerative Retinoschisis (Senile Retinoschisis)
This form, sometimes called SR, usually affects men and women in their 50s to 70s, but it can start earlier in life. It’s not as serious as the juvenile form and rarely causes vision loss.
Causes
SR isn't caused by a problem gene, and it's not passed down through families. Doctors don't know exactly why the retina becomes damaged as some people get older.
Symptoms
SR doesn't usually cause vision loss or other symptoms and, typically, is only found during an eye exam. Over time, some people lose a little of their side vision. In rare cases, the retina can become detached.
Diagnosis
Tests your eye doctor might recommend include:
- Visual acuity test to check how well you can focus
- Field of vision test to measure your central and side vision
- Ophthalmoscopy with dilation to look at the back of your eye, including the retina
- Slit lamp exam to get a large, three-dimensional (3-D) view of the different parts of your eye
Treatment
People with degenerative retinoschisis usually don't need treatment. See your eye doctor for regular checkups to make sure you don’t have any vision loss. If the retina detaches, your doctor will treat it with surgery.