Artery & Vein Occlusions
Retinal Artery & Vein Occlusion
To function properly and make vision possible, the retina requires a continuous supply of oxygenated blood to flow through the retinal vascular system, which consists of the central retinal artery, branches, and blood vessels.
A retinal artery occlusion occurs when the central retinal artery or one of its branches becomes blocked, typically by a small blood clot or cholesterol plaque. A central retinal artery occlusion (CRAO) is sometimes referred to as an “eye stroke.” A retinal vein occlusion is when the blockage occurs in the central retinal vein or one of its branches. If an occlusion occurs near the macula, it can cause a sudden decrease in vision, blurriness, or distortion. However, if the macula is not impacted, symptoms may not be noticeable.
Risk factors for retinal artery and vein occlusions include:
- High blood pressure
- High cholesterol
- Blood clotting disorders
- Heart disease
- Carotid arteries disease
In severe cases, especially in cases of CRAO, patients can experience advanced loss of vision. It’s important to note that CRAO is a medical emergency that requires immediate care. Furthermore, CRAO increases your likelihood of having a cerebral stroke.
How are retinal artery and vein occlusions diagnosed?
Retinal artery and vein occlusions are diagnosed through a comprehensive eye exam, which includes eye dilation and ophthalmoscopy. Your doctor will also capture images of your retina using optical coherence tomography (OCT), which is an imaging technique that uses infrared light. Your doctor may also perform fluorescein angiography, which involves injecting a dye into the bloodstream to highlight the retinal vascular system and find the presence of abnormal blood vessel growth or leakage.
Can retinal artery and vein occlusions be treated?
Currently, there is no cure for retinal artery and vein occlusions. Doctors typically recommend that patients who are at risk for developing a retinal artery or vein occlusion practice preventative measures by managing underlying medical issues such as high blood pressure or cholesterol. In some cases, anti-vascular endothelial growth factor (anti-VEGF) medications may be injected into the eye to slow the growth of abnormal blood vessels. Laser therapy may also be used to seal leaking blood vessels, treat swelling (edema) or new blood vessel growth.
Retinal vein occlusion
Retinal vein occlusion refers to a blockage or slow-down of blood flow through one of the blood vessels in the retina that is taking the blood out of the eye and back towards the heart. This can happen to the central retinal vein or one of its branches, and leads to an abrupt decrease in vision if it involves the macula at the center of the eye. If it does not involve the macula it may not have any associated symptoms.
The risk factors for a retinal vein occlusion include high blood pressure, glaucoma, heart disease, obesity, and clotting disorders. It can occur at any age, but most commonly happens after the age of 50.