There are two types of RVO:

• Central retinal vein occlusion (CRVO): Blockage of the main retinal vein
• Branch retinal vein occlusion(BRVO): Blockage of one of the smaller branch veins

n Non-ischemic (perfused)
n Ischemic (nonperfused)

What causes RVO?

The blockages that occur with retinal vein occlusion are often due to the hardening of arteries and blood clots. As the arteries and veins intersect over one another within the retina, a hardened artery can push against a vein. This narrows the opening of the vein, causing uneven blood flow and creating blood clots. Additionally, this may lead to haemorrhages (bleeding) and leakage of fluid from the blocked blood vessels.

The risk factors of retinal vein occlusion are:

• Old age (RVO is commonly detected among the elderly)
• Diabetes
• Glaucoma
• High blood pressure (hypertension)
• Atherosclerosis
• Smoking
• Overweight
• Vitreous haemorrhage
• Trauma to the eye

What are the symptoms of Retinal Vein Occlusion?

• Pain or pressure felt in the eye
• Noticeable dark spots or lines floating in your vision
• Partial or total blurriness in vision. Loss of vision is also a possibility. The degree of blurriness or vision loss may be mild at the beginning but will get worse in as soon as a few hours or days. There is also a possibility of complete sudden blindness.

Due to the severity of the condition, schedule an appointment immediately with Eyecentric specialists if you notice such symptoms. RVO can cause permanent retina damage and may lead to other eye problems.

Retinal Vein Occlusion diagnosis

After asking about your medical history, the ophthalmologist will first use some eye drops to dilate your pupils. This is to enable the specialist to use an ophthalmoscope to check your retina for any blockage or bleeding.

The ophthalmologist may decide to conduct a fluorescein angiography as an additional precaution. A harmless dye is injected into your arm and as the dye travels through your bloodstream and into the retina, the eye doctor will take special photographs of the eye for closer examination of the blood vessels.

An optical coherence tomography test may also be suggested, which involves the use of an advanced scanning ophthalmoscope (resolution of 5 microns) that produces high-definition images of your retina.

What is the treatment for Retinal Vein Occlusion?

There is no known way of unblocking affected retinal veins. However, your doctors will be able to treat the complications that commonly arise due to the condition and help protect your vision.

• Intravitreal injection of anti-vascular endothelial growth factor (VEGF) drugs – A specific drug that targets substances that cause the fluid build-up in your retina. Administration can help reduce the swelling taking place
• Intravitreal injection of corticosteroid drugs – Steroid administration to help with inflammation
• Focal laser therapy – Laser is used to seal off blood vessels that lie near the macula and stop them from leaking
• Pan-retinal photocoagulation therapy – A laser is used to create tiny burns on the retina to stop blood vessels from leaking and growing

It is important to note that like all surgeries, the degree of success varies among patients. Some patients may experience little improvement while others may regain some of the vision loss after a few months.

What can I do to prevent Retinal Vein Occlusion?

RVO usually occur among patients who have an underlying medical condition. For this reason, it is crucial to always maintain overall health with regular exercise, a low-fat healthy diet, controlling your blood pressure and cholesterol levels, not smoking and maintaining a healthy weight. People with diabetes are advised to undergo eye checks annually.

At Eyecentric based at Bukit Tinggi Medical Centre, our team of seasoned ophthalmologists and eye surgeons is dedicated to delivering the best care possible to help you maintain your vision. Book an appointment if you have concerns regarding your eyesight.