transient monocular blindness (TMB); amaurosis fugax

Etiology

• transient ischemic attack (painless)
• temporal arteritis (elevated ESR)
• optic nerve disorders
  • optic neuritis
  • ischemic optic neuropathy
  • papilledema - pseudotumor cerebri
• ocular disorders
  • acute glaucoma (expectation of painful vision loss) [ABIM]
  • retinal artery branch occlusion
  • central retinal vein occlusion
  • retinal detachment
  • retinal artery vasospasm

Clinical manifestations

• may obscure only the upper or lower 1/2 of vision in one eye, the entire visual field in one eye, or may be perceived by the patient as a graying of vision
• retinal detachment may appear as a black curtain that progresses across the visual field

Diagnostic procedures

• dilated opthalmoscopy
  • abnormal visual acuity testing or visual field testing
  • eye pain
  • history of glaucoma or optic neuritis

Radiology

• carotid doppler ultrasound
• MRI of brain with diffusion weighted imaging (see TIA)

Complications

• predicts blindness in patients with temporal arteritis

Management

• treat transient ischemic attack (TIA) if likely cause
• prognosis
  • epsiode of transient monocular blindness confers lower risk of subsequent stroke than does hemispheric TIA
• carotid endarterectomy beneficial only for high-risk patients

More general terms

• blindness
• visual impairment