Branch Retinal Vein Occlusion (BRVO) Workup

Updated: Sep 28, 2018
  • Author: Lihteh Wu, MD; Chief Editor: Douglas R Lazzaro, MD, FAAO, FACS  more...
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Laboratory Studies

The authors of the Branch Vein Occlusion Study (BVOS) have recommended against extensive testing in patients with typical BRVO. [19]

Certain laboratory studies may be useful in atypical cases (ie, bilateral cases, those in young patients, those in patients with a personal or family history for thromboembolism). Determinations of the following may be helpful:

  • Prothrombin time (PT) and activated partial thromboplastin time (aPTT)

  • Protein C, protein S, factor V Leiden, and antithrombin III

  • Homocysteine

  • Antinuclear antibody (ANA), lupus anticoagulant, and anticardiolipin

  • Serum protein electrophoresis (SPEP) results


Imaging Studies

Fluorescein angiography

A fluorescein angiogram is obtained as soon as the hemorrhages have cleared if the patient's vision is still depressed. The test is usually performed 3 months after the event.

The purpose is to determine the cause of the visual loss (eg, macular edema, macular ischemia). If the visual loss is secondary to macular edema, laser photocoagulation in a grid pattern may be of benefit. Conversely, if macular ischemia is responsible for the visual loss, laser photocoagulation should not be offered.

Fluorescein angiograms should be performed periodically to assess for retinal nonperfusion. Wide-angle angiograms are preferred.

Angiogram images are shown below.

Patient with an old branch retinal vein occlusion Patient with an old branch retinal vein occlusion in which the hemorrhages have cleared. Note lipid exudation and evidence of cystoid macular edema.
Arterial phase of an angiogram demonstrates the la Arterial phase of an angiogram demonstrates the lack of filling in the first branch arteriole of the superior temporal artery.
Late phase of an angiogram demonstrates late leaka Late phase of an angiogram demonstrates late leakage in the macular area.

Optical coherence tomography (OCT)

Given its ability to measure retinal thickness in a quantitative fashion, OCT is a useful adjunct in the follow-up of patients with macular edema secondary to BRVO.

See the images below.

Optical coherence tomography (OCT) of a patient wi Optical coherence tomography (OCT) of a patient with macular edema secondary to branch retinal vein occlusion (BRVO) prior to the initiation of anti-VEGF therapy. The visual acuity was 20/150.
Optical coherence tomography (OCT) following 3 mon Optical coherence tomography (OCT) following 3 monthly intravitreal bevacizumab injections (1.25 mg). The visual acuity improved to 20/30.

Optical coherence tomography angiography (OCTA) is a new imaging modality that can visualize the microcirculation of the retina. Unlike fluorescein angiography, OCTA does not require dye injection and clearly delineates the different retinal capillary plexuses. In a small series of 10 eyes with BRVO, foveal avascular zone enlargement was seen in both the superficial and deep capillary plexuses. Capillary nonperfusion was mostly documented in the superficial capillary plexus. [20]


Histologic Findings

Histopathologic studies confirm the importance of arteriovenous crossings in the pathogenesis of this condition. Inner retinal ischemic atrophic areas have been described distal to the occlusion site. Variable degrees of arteriolar sclerosis have been reported. An intravascular fresh or recanalized thrombus is often found at the site of venous occlusion.