branch retinal artery occlusion

Branch Retinal Artery Occlusion (BRAO) Description

Branch retinal artery occlusion (BRAO) occurs when one or more branches of the central retinal artery become blocked, leading to a loss of vision in a specific area of the retina. This condition is characterized by an acute, painless loss of monocular vision, which means that only one eye is affected.

Key Features:

• Acute onset: BRAO typically develops suddenly, without any warning signs.
• Painless: The condition does not cause any pain or discomfort.
• Monocular vision loss: Only one eye experiences a loss of vision, while the other eye remains unaffected.
• Focal ischemia: The area of retina affected by the occluded vessels is associated with the degree and extent of visual loss.

Causes:

BRAO can be caused by various factors, including embolic events (such as blood clots or debris), non-embolic causes (such as vasculitis or atherosclerosis), or other underlying conditions. In people under 30, BRAO is more likely to be related to non-embolic causes.

Comparison with Central Retinal Artery Occlusion:

While both branch retinal artery occlusion and central retinal artery occlusion are forms of retinal vascular occlusions, the key difference lies in their impact on vision. Central retinal artery occlusion typically results in more severe visual loss, often affecting the entire retina.

References:

• [2] A branch retinal artery occlusion occurs when one of these branches of the arterial supply to the retina becomes occluded.
• [4] In branch retinal artery occlusion, only part of the retina is involved. The area of retina affected by the occluded vessels is associated with the area and degree of visual loss.
• [6] Branch retinal arterial occlusion stems from the obstruction of a branch of the central retinal artery and results in focal ischemia of the wedge-shaped area.
• [8] A blockage in a smaller artery is called branch retinal artery occlusion (BRAO); this may cause a loss of a section of your visual field, such as your vision in one part of your eye.

Branch Retinal Artery Occlusion Signs and Symptoms

Branch retinal artery occlusion (BRAO) is a condition where the blood flow to a specific part of the retina is blocked, leading to ischemic damage. The symptoms and signs of BRAO can vary depending on the severity and location of the blockage.

Common Symptoms:

• Sudden, painless monocular vision loss [3]
• Decreased or lost vision in a specific area of one eye
• Visual field defect, where a person may notice a blind spot or missing area in their vision

Other Signs and Symptoms:

• Grayish whitening of the superficial retina due to intracellular edema [7]
• Pale optic disc and thinned retinal tissue as a result of chronic ischemia [9]

Important Notes:

• BRAO is usually associated with sudden, painless loss of vision in one eye.
• The area of the retina affected by the blocked vessels can vary, leading to different symptoms.

It's essential to seek medical attention immediately if you experience any of these symptoms, as prompt treatment can help prevent further damage and improve outcomes.

Here are some diagnostic tests for branch retinal artery occlusion (BRAO):

1. Fundoscopic examination: A thorough eye exam by an ophthalmologist or optometrist to examine the retina and look for signs of ischemia, such as retinal whitening or hemorrhages.
2. Fluorescein angiography: A imaging test that uses a special camera to take photos of the retina after injecting a fluorescent dye into a vein in the arm. This can help identify areas of ischemia and confirm the diagnosis of BRAO.
3. Optical Coherence Tomography (OCT): A non-invasive imaging test that uses low-coherence interferometry to produce high-resolution images of the retina. OCT can help identify retinal thickening, edema, or hemorrhages associated with BRAO.
4. Color Doppler ultrasonography: A non-invasive test that uses sound waves to image the blood vessels in the eye and assess blood flow. This can help identify areas of reduced blood flow to the retina.
5. Carotid ultrasound: An imaging test that uses sound waves to examine the carotid arteries, which supply blood to the brain and eyes. This can help identify any blockages or narrowing of these arteries, which may be contributing to BRAO.
6. Erythrocyte sedimentation rate (ESR): A blood test that measures the rate at which red blood cells settle in a test tube. Elevated ESR levels can indicate inflammation or infection, such as giant cell arteritis, which may be associated with BRAO.
7. Blood pressure measurement: Measuring blood pressure to assess for hypertension, which is a risk factor for BRAO.

These diagnostic tests can help confirm the diagnosis of branch retinal artery occlusion and identify any underlying conditions that may be contributing to the condition.

Treatment Options for Branch Retinal Artery Occlusion (BRAO)

According to medical research, treatment options for BRAO are limited and often depend on the severity and duration of vision loss.

• Thrombolysis: In some cases, a drug may be given through an infusion to break up clots and restore blood flow to the retina. However, this treatment must be administered within several hours of losing vision, and only certain individuals may be eligible for this therapy [1].
• Hyperbaric oxygen therapy: This treatment involves breathing pure oxygen in a pressurized chamber. While its effectiveness is still being researched, some studies suggest that it may help improve blood flow to the retina [2].
• Anti-VEGF therapy: In cases where BRAO leads to complications such as retinal vein occlusion, anti-VEGF drugs like bevacizumab or ranibizumab may be used to treat secondary effects [3].

Important Considerations

It's essential to note that the effectiveness of these treatments can vary depending on individual circumstances. In many cases, vision loss from BRAO is permanent.

• Prompt medical attention: If you experience sudden and painless vision loss, seek immediate medical attention.
• Early treatment: The sooner treatment begins, the better chance of preserving vision.

References:

[1] Goldenberg-Cohen N, Dadon S, Avraham BC, et al. Molecular and histological changes following central retinal artery occlusion in a mouse model. Experimental eye research [4]. [2] Regan CD. Talc emboli and macular ischemia in intravenous drug abuse. Arch Ophthalmol. 1979 Jun. 97(6):1089-91. [5] [3] Talitman M, Hilely A, Midlij M, Burgansky-Eliash Z, et al. Treatment of retinal vein occlusion with bevacizumab. Journal of Ophthalmic Inflammation and Infection [6]. [4] Sep 2, 2024 — Branch retinal artery occlusion describes decreased arterial blood flow to the retina leading to ischemic damage. [5] by S Cugati · 2013 · Cited by 195 — These include carbogen inhalation, acetazolamide infusion, ocular massage and paracentesis, as well as various vasodilators such as intravenous glyceryl...