Other retinal conditions

A Branch Retinal Vein Occlusion (BRVO) is a common retinal condition. It occurs when there is a blockage in one of the veins that drains blood from the retina. Depending on the location of the vein, this can result in complications such as retina haemorrhages, macular oedema, macular ischaemia and neovascularisation (new vessel growth).

If the blockage is in the periphery the patient may be asymptomatic. If the blocked vein causes central macular oedema (thickening of the retina) or macular ischaemia, patients usually present with blurred vision in that eye. Occasionally the new vessels may bleed causing floaters or complete loss of vision.

BRVOs usually occur at the point a vein and an artery cross and are commonly associated with hypertension, diabetes, smoking and high cholesterol. Other rarer associations include some forms of ocular inflammation and blood disorders.

Dr Cohn can diagnose a BRVO by examining the back of the eye and taking detailed retinal images. Occasionally a fluorescein angiogram is performed to identify new vessels and the areas of blockage.

If the blockage is away from the centre of the retina and there are no new vessels, patients can often be safely monitored.

If there is macular oedema affecting the vision, first line treatment involves intravitreal injections. This is where a drug such as an anti-vascular endothelial growth factor (VEGF) or a steroid is injected into the back of the eye. This is done in the doctor’s rooms with local anaesthetic. Anti-VEGF medications are special antibodies that blocks a substance called vascular endothelial growth factor that causes blood vessels to grow and leak fluid. There is a small chance of a complication with intravitreal injections such as an infection, cataract or retinal detachment, however these are very rare. Often multiple injections are required to stabilise the vision.

Dr Cohn will discuss the best treatment option for you.

There is no treatment for macular ischaemia.

If new vessels develop, scatter laser photocoagulation may be performed to reduce the risk of vitreous haemorrhage and other complications.

A Central Retinal Vein Occlusion (CRVO) occurs when the main vein that drains blood away from the retina becomes blocked. The severity varies but usually results in retinal haemorrhages, macular oedema, macular ischaemia and occasionally new blood vessel growth on the iris at the front of the eye.

Patients usually present with loss of vision in the affected eye. Occasionally the presentation is with a painful type of glaucoma called neovascular glaucoma.

CRVOs are associated with hypertension and other risk factors such as smoking, poorly controlled diabetes and high cholesterol. There are also rarer causes in younger people.

Dr Cohn can diagnose a CRVO by examining the back of the eye and taking detailed retinal images. Occasionally a fluorescein angiogram is performed to identify new vessels and the areas of blockage.

Macular oedema in CRVOs is commonly treated with intravitreal injections of either anti-vascular endothelial growth factor (VEGF) medications or steroid. These are performed in Dr Cohn’s rooms with local anaesthetic and often need to be repeated to stabilise the vision.

There is no treatment for macular ischaemia.

If new vessels are seen on the iris, urgent pan-retinal laser may be required to prevent neovascular glaucoma.

Central Serous Chorioretinopathy (CSCR or CSR) is a common condition that usually affects young people between the ages of 20-50. It is more common in males.

Fluid accumulates underneath the retina and if this occurs at the central macular it results in blurred vision. Patients usually present with central distortion or blurred vision in one eye.

In most cases, a clear cause is never identified. However, stress and use of steroid medications are thought to be associated in certain cases.

Patients usually have a dilated retinal examination as well as tests such as Optical Coherence Tomography (OCT). Fluorescein angiography (FA) and Indocyanine Green (ICG) may also be used to investigate leakage and related retinal changes.

In most cases CSCR resolves spontaneously and no treatment is required. More than 90% of patients return to normal or near-normal vision within 3 to 4 months, although some may continue to notice reduced colour vision, night vision or distortion.

If fluid persists, treatment can be considered when there is no spontaneous improvement.

Laser photocoagulation may be used when a small area of leakage is identified away from the central macula, while photodynamic therapy (PDT) with Verteporfin may be used when the centre of the macula is involved.