Branch retinal artery occlusion (BRAO) is a rare retinal vascular disorder in which one of the branches of the

central retinal artery The central retinal artery (retinal artery) branches off the ophthalmic artery, running inferior to the optic nerve within its dural sheath to the eyeball. Structure The central retinal artery pierces the eyeball close to the optic nerve, sendin ...

is obstructed.

Presentation

Abrupt painless loss of vision in the visual field corresponding to territory of the obstructed artery is the typical history of presentation. Patients can typically define the time and extent of visual loss precisely. Retinal whitening that corresponds to the area of

ischemia Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems wi ...

is the most notable finding. In chronic phase the retinal whitening disappears.

Risk factors

Risk factors include: *

Hypertension Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...

* Elevated lipid levels *

cigarette smoking Tobacco smoking is the practice of burning tobacco and ingesting the resulting smoke. The smoke may be inhaled, as is done with cigarettes, or simply released from the mouth, as is generally done with pipes and cigars. The practice is believed ...

Diabetes Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ap ...

* Susac's syndrome - This is one of the key symptoms of the disease.

Diagnosis

Ancillary testing is not usually necessary to make the diagnosis.

Fluorescein angiography Fluorescein angiography (FA), fluorescent angiography (FAG), or fundus fluorescein angiography (FFA) is a technique for examining the circulation of the retina and choroid (parts of the fundus) using a fluorescent dye and a specialized camera. S ...

reveals an abrupt diminution in dye at the site of the obstruction. Visual field testing can confirm the extent of visual loss.

Treatment

No proved treatment exists for branch retinal artery occlusion. In the rare patient who has branch retinal artery obstruction accompanied by a systemic disorder, systemic anti-coagulation may prevent further events.

Epidemiology

The mean age of affected patients is 60 years. The right eye is affected more commonly than the left eye which probably reflects the greater possibility of cardiac or aortic emboli traveling to the right carotid artery. Most of the cases are due to

emboli An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule ( fat embolism), a bubble of air or other gas (gas embolism), amniotic fluid ( amni ...

to the retinal circulation. Three main types of retinal emboli have been identified: Cholesterol, calcific, and fibrin-platelet.

References

External links

{{Medical resources , ICD10 = , ICD9 = , ICDO = , OMIM = , DiseasesDB = , MedlinePlus = , eMedicineSubj = artery , eMedicineTopic = 1223362 , MeSH = , GeneReviewsNBK = , GeneReviewsName = , Orphanet = Diseases of arteries, arterioles and capillaries Disorders of choroid and retina