What is Retinoschisis?
Separation of the layers of the retina is known as retinoschisis. The tissue present inside the back of the eye is retina. Retina transforms a person’s visuals into electrical signals which travel to the brain. When there is separation of retina, there is formation of cysts or tiny lumps between the retinal layers. These cysts cause nerve damage and prevent the light signals from being transmitted to the brain. Additionally the damaged nerves cause blurry vision in the patient.
What are the Types of Retinoschisis?
There are two types of Retinoschisis: Degenerative (Senile) Retinoschisis and Juvenile X-linked retinoschisis.
What is Juvenile X-Linked Retinoschisis?
Also known as XJR, this is a rare condition and primarily affects boys and men. Juvenile X-Linked Retinoschisis causes damage to macula, which is a region in the middle of the retina. The macula is responsible for providing clear central vision, and allows a person to focus on things in front of them such as computer or a book. In some patients, Juvenile X-Linked Retinoschisis can also affect the peripheral vision.
What are the Causes of Juvenile X -Linked Retinoschisis?
Juvenile X-Linked Retinoschisis occurs as a result of gene mutation. If a parent passes the defected gene to their girl, then she will become a carrier of Juvenile X-Linked Retinoschisis, but will not have symptoms. If the defected gene passes to the boy, then he will suffer from Juvenile X -Linked Retinoschisis.
If the mother has the problematic gene, then her daughter will have a 50% chance of being a carrier of X -Linked Retinoschisis and the sons will have 50% chance of having X -Linked Retinoschisis. Men carrying the X -Linked Retinoschisis gene will not pass it to their sons; however, their daughters will be carriers.
What are the Symptoms of X -Linked Retinoschisis?
- Symptoms develop in the first few months of the child’s life.
- X -Linked Retinoschisis commonly affects both the eyes and starts at birth.
- In some cases, the patient is not diagnosed until after starting school where they will have problems with reading.
- Patient’s vision commonly worsens during childhood and then plateaus after some time.
- After a man reaches the ages of 50 to 60, his vision starts deteriorating again. There are some patients who lose a lot of their vision by the time they reach adulthood. Retinoschisis, however, rarely causes blindness.
- Patient will have strabismus, i.e. eyes which look in different directions.
- Patient suffers from far-sightedness.
- The damaged blood vessels cause bleeding in the eye.
- Rarely, the retina completely separates from the eye. This is known as retinal detachment and is a serious condition as it can lead to loss of vision. Surgery is needed to fix retinal detachment.
How is the Diagnosis of X -Linked Retinoschisis Made?
- Eye examination is done where the patient’s eye is checked for tears or splits in the retina.
- Ultrasound uses sound waves to generate pictures of the eyes and is helpful in detecting bleeding in the eye.
- Optical Coherence Tomography (OCT) uses light waves to generate pictures of the retina.
- Electroretinogram (ERG) measures the electrical activity in the retina. The doctor places a special sensor in each eye and while the patient is looking at a flashing light, the patient’s eye is checked to see how the retinas respond.
- Gene tests are done to look for the RS1 gene which is responsible for causing juvenile X-linked retinoschisis.
- Regular eye exams are highly recommended for patients with juvenile retinoschisis to check for vision loss.
What is the Treatment of X -Linked Retinoschisis?
- A divided retina cannot be fixed with any medicine or surgery.
- Glasses also don’t help if nerve damage is the cause of bad vision; however, glasses help if the patient is farsighted or nearsighted. For school children, large-print computer screens, textbooks and low-vision tools are helpful.
- Laser or cryotherapy is used to treat bleeding in the eye. This treatment will close the damaged blood vessels of the retina.
- Surgery is required to fix a detached retina.
- Research is going on regarding new treatments for X -Linked Retinoschisis. One of the new treatment consists of replacing the damaged gene with a copy of a healthy gene. Research is also going on regarding stem cell treatment for X -Linked Retinoschisis.
What is Degenerative Retinoschisis (Senile Retinoschisis)?
Senile Retinoschisis or Degenerative Retinoschisis (also referred to as SR) commonly affects men and women in the ages between 50 to 70; however, it can also start earlier in life. Degenerative Retinoschisis is not as serious as the juvenile form and it rarely causes loss of vision.
What are the Causes of Degenerative Retinoschisis?
The cause of Degenerative Retinoschisis is not a defected gene and neither does it pass from parents to their children. The exact cause of Degenerative Retinoschisis is not known as to why there is damage to retina with aging.
What are the Symptoms of Degenerative Retinoschisis?
Patients with Degenerative Retinoschisis do not experience any symptoms or vision loss. Degenerative Retinoschisis is often detected during an eye exam. As time goes on, there is loss of some peripheral vision in some patients. The retina can become detached in rare cases.
How is the Diagnosis of Degenerative Retinoschisis made?
The following tests are done to diagnose degenerative retinoschisis.
- Field of vision test is done to measure patient’s side vision and central vision.
- Visual acuity test helps in checking how good the patient’s focus is.
- Slit lamp exam helps in getting a large, three-dimensional (3-D) image of the various parts of the eye.
- Ophthalmoscopy is done look at the posterior side of eye, including retina.
What is the Treatment for Degenerative Retinoschisis?
Treatment is usually not needed for patients with degenerative retinoschisis. Patient should get regular eye checkups done to detect any vision loss. If there is detachment of the retina, then surgery is done to fix it.