Features

Branch retinal vein occlusion

Disease

DESCRIPTION, SYMPTOMS, SIGNS, PREVALENCE, SIGNIFICANCE, DIFFERENTIAL DIAGNOSIS

See Branch retinal vein occlusion - Assessment.

MANAGEMENT

Urgent

Initial management relates to any underlying systemic disease or possible glaucoma. Treatment may help to reduce the risk of stroke (cerebrovascular accident) or an additional subsequent ocular vascular occlusion.

Blood tests
Patients need a full blood workup to treat any underlying systemic risk factors such as hypertension, diabetes, carotid stenosis or cardiovascular disease.

Oral medication
Review antihypertensive and other medications, and consider daily aspirin. Discontinuation of oral contraceptives might be considered.

Ocular tests
Risk factors for glaucoma should be evaluated, and intraocular pressure reduced if necessary. Assess for neovascularisation of the disc or elsewhere on the retina. Neovascularisation of the iris, anterior angle or neovascular glaucoma are rarer complications.

Fluorescein angiography may be indicated to assess retinal capillary non-perfusion; the presence of an area of more than five disc diameters is a risk for development of neovascularisation. Usually a fluorescein angiography is indicated 2-3 months after a BRVO, once the haemorrhages have cleared.

Laser treatment
In many patients with BRVO, no laser treatment may be necessary. However, recognised indications are macular oedema or neovascularisation. Grid argon laser treatment for macular oedema is indicated in the presence of:

  • Reduced visual acuity (<20/40)
  • Good macular perfusion, with intact capillaries evident on angiography
  • Resolution of most of the adjacent haemorrhages (Branch retinal vein occlusion study; BRVOS).

Posterior segment neovascularisation is always a risk in BRVO if significant areas of ischaemic retina are present. If neovascularisation of the disc or retina develops after BRVO, scatter argon laser photocoagulation of the non-perfused sector is usually indicated. Such laser treatment of the affected area reduces the likelihood of complications such as vitreous haemorrhage, fibrosis or retinal traction. Prophylactic argon laser treatment to prevent neovascularisation is not usually conducted.

There is a low risk of anterior segment neovascularisation in BRVO; however, the development of iris neovascularisation may require sectorial or panretinal photocoagulation.

Collateral blood vessels are not photocoagulated because they facilitate improved vascular circulation. They may be differentiated from neovascularisation by means of fluoroscein angiography, as collateral blood vessels are typically not leaky. Photocoagulation of a retinal arterial macroaneurysm may be considered if it is persistently leaky for several months, causing macular oedema, haemorrhage or exudation.

Advice and review
The visual prognosis is usually good, unless the BRVO has caused chronic macular oedema or significant macular capillary loss is present with poor perfusion. There should be follow-up of any underlying medical conditions. Consider regular review at 1-2 month intervals for the first 12 months to monitor visual acuity, and to check for macular oedema or neovascularisation. The patient may be provided with a home Amsler grid to check for subjective macular changes.