Central & Branch Retinal Artery Occlusions

Key Features

Essentials of Diagnosis

• Sudden monocular loss of vision

• No pain or redness

• Widespread or sectoral retinal pallid swelling

General Considerations

• In patients aged 50 years or older with central retinal artery occlusion, consider giant cell arteritis

• Carotid and cardiac sources of emboli must be sought so that treatment can be given to reduce the risk of stroke

• In young patients, causes include

  • Migraine

  • Oral contraceptives

  • Systemic vasculitis

  • Congenital or acquired hypercoagulable states (thrombophilia) (see below)

• Internal carotid artery dissection should be considered when there is neck pain or a recent history of neck trauma

• In all patients, consider

  • Diabetes mellitus

  • Hyperlipidemia

  • Systemic hypertension

Clinical Findings

Symptoms and Signs

• Central retinal artery occlusion

  • Presents as sudden profound monocular visual loss

  • Visual acuity is usually reduced to counting fingers or worse

  • Visual field is restricted to an island of vision in the temporal field

• Branch retinal artery occlusion

  • May also present with sudden loss of vision if the fovea is involved, but more commonly sudden loss of visual field is the presenting complaint

  • Fundal signs of retinal swelling and adjacent cotton-wool spots are limited to the area of retina supplied by the occluded artery

• Identify risk factors for a cardiac source of emboli including arrhythmia, particularly atrial fibrillation, and cardiac valvular disease; and check the blood pressure

• Clinical features of giant cell arteritis include

  • Jaw claudication (which is very specific)

  • Headache

  • Scalp tenderness

  • General malaise

  • Weight loss

  • Polymyalgia rheumatica: shoulder and hip girdle pain

  • Tenderness or thickening of, or absence of pulse in, the superficial temporal arteries

Diagnosis

Laboratory Tests

• Test for diabetes (fasting serum glucose, hemoglobin A_1C) and hyperlipidemia (fasting serum cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) in all patients

• Erythrocyte sedimentation rate and C-reactive protein are usually markedly elevated in giant cell arteritis but one or both may be normal

• Consider testing for other types of vasculitis (eg, antinuclear antibody, rheumatoid factor, anticytoplasmic neutrophil antibody)

• In younger patients, consider tests for congenital or acquired hypercoagulable states (thrombophilia)

  • Antiphospholipid antibody syndrome (lupus anticoagulant)

  • Activated protein C resistance/Factor V Leiden

  • Protein C, protein S deficiency

  • Antithrombin deficiency

  • Hyperprothrombinemia (G20210A prothrombin gene mutation)

  • Increased Factor VIII activity

  • Hyperhomocysteinemia

Imaging Studies

• Obtain duplex ultrasonography of the carotid arteries, ECG, and echocardiography (with transesophageal echocardiography, if necessary), to identify carotid and cardiac sources of emboli

• When indicated, obtain CT or MR angiography studies for internal carotid artery dissection

Diagnostic Studies

• Central artery occlusion: Ophthalmoscopy

  • Reveals pallid swelling of the retina with a cherry-red spot at the fovea

  • The retinal arteries are attenuated, and "box-car" segmentation of blood may be seen in the retinal veins

  • Occasionally, emboli are seen in the central retinal artery or its branches

• Optical ...