The Problem
A Central Retinal Vein Occlusion (CRVO) is when the main veins that drain blood away from the retina are blocked. You can think of it like a traffic jam that blocks the major highways in they eye. This blockage disrupts blood flow in your eye leading to vision problems. This can be noted as a sudden blurring or vision loss in the eye.
A Branch Retinal Vein Occlusion (BRVO) is when part of the veins in he eye are blocked. This causes sudden blurring or vision loss in part of the eye.
A vein occlusion is the blockage of veins carrying blood out of the eye by a hardened artery. Therefore, even though it is the vein that is blocked, this should be thought of as being due to an arterial disease. Dr. Adatia would like your family doctor to check your blood pressure, cholesterol, and blood sugar to ensure these are controlled.
In patients younger than 50 years old, additional testing will be suggested. In general, this should be thought of like a stroke in the eye. In fact, these are the same risk factors for stroke and heart attack.
When the vein is blocked by an artery, the area before the blockage tends to explode with blood leaking out and damage occurring to the vein. The vein can heal over time.
Treatment is to help remove the leakage into the retina, or light sensitive tissue at the back of the eye, from the blocked vein while the vein heals. The fluid that leaks out of the vein reduces vision.
The Procedure
Treatment is with anti-VEGF injections in the eye to reduce the leakage.
Treatment is to help remove the leakage from the blocked vein while the vein heals. The fluid that leaks out of the vein reduces vision. Although treatment has been demonstrated to improve vision by decreasing leakage, it can not undo damage done to the retina from lack of blood flow. This damage can sometimes limit visual improvement.
Risks?
Treatment is with anti-VEGF injections in the eye to reduce the leakage.
The main risk is 1 in 5,000 of bleeding, infection, or retinal detachment. The eye can feel itchy or scratchy on the day of the injection; this usually improves by the following day. The eye is frozen, so most people do not feel the treatment. After the treatment, Dr. Adatia suggests using preservative free artificial tears every 15 minutes for 2 hours. The reason for this is that, as the eye is frozen, we do not blink normally, and the eye can get dry and painful from decreased blinking. Using the drops help prevent that and often people will remain comfortable even on the day of treatment.
If there is persistent pain and decreased vision that does not improve on the following day, Dr. Adatia would like to see you back right away. Often this is just from a scratch or an abrasion on the cornea or front of the eye. However, infection would need to be ruled out. If pain and decreased vision persists and does not improve the next day, please call in to see Dr. Adatia. If it is an evening or a weekend, patients are advised to go to the Rockyview Emergency Department in Calgary.
Otherwise, the white of the eye can be red if there is a small bruise around the injection site. Like a bruise, this typically changes color and goes away on its own over the next few weeks.
At the time of the injection, you may notice floating material; that is the medication, and it should disperse over hours.
In general, this is a very safe and common procedure.