Branch Retinal Vein Occlusion (BRVO)

*Please note that this information is for illustrative purposes only, providing a general overview on the topics listed. For any specific questions or concerns regarding your condition, please contact our office so that you can consult with the appropriate person or department to address your needs.


A branch retinal vein occlusion (BRVO) occurs suddenly as loss of vision in an area of your visual field. A BRVO originates from the compression of a branch retinal vein from an overlying branch retinal artery.

Blood normally enters the eye through the central retinal artery that comes out of the center of the optic nerve. Blood then flows through the four retinal arteries, into smaller retinal arterioles and into capillaries where oxygen is exchanged into the retinal tissues. The blood then flows from the capillaries to the smaller retinal venules and into one of the four large retinal veins. Each of these four retinal veins flow into the central retinal vein in the optic nerve.   

Pathogenesis (Origin and Development of a Disease)

Branch retinal vein occlusion (BRVO) occurs in some patients, typically those with hypertension or hypercholesterolemia, from progressive hardening of retinal arteries that occurs with age over time. The hardened retinal arteries cross over and compress softer retinal veins on the surface of the retina and share a common retinal sheath.

A BRVO occurs at an arterial/venous crossing when the overlying artery compresses the underlying vein and blocks the blood from exiting the retina. This allows blood to flow through the artery but prevents the blood from flowing out of the retina because of the compression of the branch retinal vein.

The pressure in the retina builds up and blood, serum and exudate spill into the retina in the area supplied by the retinal vein and artery.  Excessive fluid builds up in the center of the macula and causes Cystoid Macular Edema (CME).

Subtypes of BRVO

There are two types of BRVO’s.  In a Non-Ischemic BRVO the retinal circulation is mostly intact.  In an Ischemic BRVO the occlusion is so severe that there is permanent loss of capillaries in the microcirculation in the macula and/or peripheral retina.

Complications of BRVO

Ischemic BRVO can lead to the development of abnormal growth of blood vessels on the retina (Neovascularization Elsewhere or NVE). These new blood vessels are weak and can rupture open and cause a Vitreous Hemorrhage (VH) to develop.

Ischemic BRVO can also lead to development of abnormal growth of blood vessels in the front of the eye on the iris called Rubeosis Iridis (RI) and over the trabecular meshwork called Neovascularization of the Angle (NVA) which is the drain where fluid exits the eye. When the trabecular meshwork gets blocked aqueous fluid cannot get out of the eye and the intraocular pressure increases causing a condition called Neovascular Glaucoma (NVG).


The development of a Branch Retinal Vein Occlusion (CRVO) causes symptoms such as the sudden onset blurry vision or loss of vision, sometimes associated with new floaters. The visual loss typically affects a portion of the central vision and an area of the peripheral visual field.

Diagnostic Testing

Optical Coherence Tomography (OCT) is used to evaluate the macular anatomy and to rule out swelling in the center of the macula called cystoid macular edema (CME) or macular thinning from poor circulation and ischemic maculopathy (IM) in BRVO patients.

Fundus Photography (FP) is used to document the level of retinopathy and for comparision to evaluate progression at future exams.

Fluorescein Angiography (FA) is used to evaluate the macular and peripheral circulation.  Many patients with BRVO have dye leakage in the center of the macula (CME) and/or a staining of microaneuryms and loss of normal capillary circulation called macular ischemia (MI) on the FA.

B-Scan Ultrasound (B-Scan) is used to evaluate the retina in patients with a poor view of the retina (in the back of the eye) secondary to corneal opacities, cataracts, retinal hemorrhage or any other condition that makes visualization of the retina difficult with indirect ophthalmoscopy.


The treatment of a non-ischemic BRVO includes a complete medical work-up looking into underlying causes such as hypertension, hypercholesterolemia, or hypertriglyceridemia.

The treatment of ischemic BRVO’s include panretinal photocoagulation (see link to PRP) for patients who present with neovascularization elsewhere in the retina (NVE), neovascularization on the iris (NVI), and neovascular glaucoma (NVG).

Surgical Treatment Options

Vitrectomy surgery with physical removal of the vitreous gel (and vitreous hemorrhage when present) is the treatment for a BRVO with a dense vitreous hemorrhage.

The procedure is performed under local anesthesia, at one of our outpatient surgical centers or local hospitals.

The surgery is performed through three 25-gauge ports (about the width of a wire paper clip). The surgery begins by placing an infusion canula, a light pipe & a vitrectomy cutter through each of the 3 ports. The infusion cannula keeps a constant pressure in the eye while the vitrectomy cutter removes the vitreous gel and vitreous hemorrhage. As the gel is removed, balance salt solution replaces the gel in the vitreous cavity. The gel that is adherent to the retina is gently lifted off the optic nerve and macula to separate the vitreomacular adhesions. The light pipe is used by the surgeon to visualize the vitreous while it is being removed inside the eye.

After the hemorrhage and gel are removed, your physician will identify any abnormal retinal vessels called retinal neovascularization and cauterize these blood vessels. Panretinal photocoagulation will be placed in the peripheral retina to treat ischemic areas where there has been permanent damage (loss of capillaries) to the retinal circulation.

After enough vitreous is removed, the surgeon removes the surgical instruments and trocars (3 ports) and the operation is complete. No sutures are typically needed in up to 95% of cases. Antibiotic ointment and a patch are placed over the eye for one night and removed the following day in our office.

Risks & Benefits of Surgery

The benefits of vitrectomy surgery, in general, are the potential for improved vision, prevention of worsening vitreous hemorrhage (VH) and neovascular glaucoma (NVG), as well as reduction or elimination of floaters.

Some of the risks of vitrectomy surgery include:
• More rapid cataract progression (in up to 20% of patients the lens may harden or become cloudy more rapidly after the vitreous gel is removed) that may require cataract surgery 1-2 years after the vitrectomy procedure.
• Vitreous (less than 5%) or choroidal (less than 1%) hemorrhage
• Retinal break or tear (less than 5%) or Retinal Detachment (less than 1%)
• Infection/Endophthalmitis (less than 1 in 500 patients)
• Permanent loss of vision/Blindness (approx. 1 in 10,000)
• These are some of the more common and serious side effects of surgery, but there are additional risks of surgery not listed above.

Post-Operative Care

Patients are typically started on antibiotic and steroid eyedrops the day after surgery.  The frequency of these drops will be determined by the surgeon on the first post-operative day.  Some patients have a temporary increase in intraocular pressure after even uncomplicated surgery and may require additional pressure lowering drops or oral medication.

Post-Operative Expectations

Vision is usually blurry the first day after surgery but typically improves to equal or better than the pre-operative vision about a week after surgery.  Continued visual improvement often occurs over the first 6-8 weeks but some patients experience improvement even up to 6 months after surgery.

Patients typically experience little to no pain following surgery.  Surface or external irritation (feeling of having something in your eye) is common.  A deeper or more intense eye pain in not typical and may signal a more serious issue such as high intraocular pressure, serous or hemorrhagic choroidals or infection.  A deeper or more intense eye pain needs to be reported to your surgeon immediately.

Post-Operative Restrictions

Post-operative restrictions are for 4 weeks after surgery and include:
• Anything that creates a Valsalva Maneuvers such as coughing, sneezing, blowing your nose, straining with bowel movements or exertion, and some of the following:
• Bending at the waist putting your head below your belt line (such as bending to tie your shoes).  Bending at the knees with your head up is allowed.
• Heavy lifting greater than 15-20 lbs.
• Strenuous activity (including lifting weights, running, yoga, pilates, aerobics, yard work, snow shoveling, laundry, housecleaning, sexual intercourse) is not recommended as it will increase your risk of developing a retina tear or detachment. Walking, for exercise, after surgery is allowed (in patients who do not require post-operative head down position).
• Showering is allowed immediately after surgery, but be sure to keep your eyes closed to prevent shower water from entering your eye.
• Swimming after surgery should be avoided for 4 weeks.  You should not put your head under water for the first 4 weeks.
• Working restrictions are job dependent.  Patients with desk jobs or who perform light stationary office work may sometimes resume work 2-3 days after surgery.  Patients with jobs that require heavy lifting or strenuous activity may be required to be out of work for 2-4 weeks. Ask your physician about your individual work restrictions.  We will be happy to provide you with a doctor’s note for your work and/or complete your temporary disability paperwork.
• Driving restrictions will be dependent on your post-operative vision and should be discussed with your physician after surgery.

*Please note that this information is for illustrative purposes only, providing a general overview on the topics listed. For any specific questions or concerns regarding your condition, please contact our office so that you can consult with the appropriate person or department to address your needs.