Transient Binocular Visual Loss
Abrupt temporary loss of vision in both eyes that lasts from seconds to hours Causes are migraine , transient ischemic attack, seizure, systemic hypertension or hypotension, papilledema
Blank, fuzzy, dark, bright, or flickering area covering all or part of visual field of both eyes, but... If visual loss is homonymous hemianopia, patients often mistakenly assign it to eye with temporal visual field loss Migraine often causes flickering zigzag ("fortification scotoma ") that migrates across visual hemifield of both eyes over a period of 20 to 30 minutes Migraine visual disturbance does not consistently affect same hemifield in successive attacks Migraine headache follows visual symptoms, but does not always occur ("acephalgic migraine") Migraine may cause migrating hemibody numbness or language difficulty but they follow visual symptoms First episode of migraine usually occurs within first three decades of life Transient ischemic attack causes blank spots or flickering spots but no zigzags or migration across visual field Transient ischemic attacks may affect both hemifields in same attack or same hemifield in repeated attacks Transient ischemic attacks last seconds to minutes Seizures cause stationary and sometimes colored flickers of variable duration Seizures may also cause head and eye deviation to one side and may lead to tonic-clonic movements and loss of consciousness Abnormally high or low blood pressure causes symptoms that mimic transient ischemic attack Papilledema causes ultra-brief (seconds) visual black-outs provoked by sitting or standing
Try to confirm that transient visual loss affected both eyes by asking if symptom was hemianopic, if disturbed vision was present with either eye closed, or if reading was disturbed Try to distinguish migraine If diagnosis not clearly migraine, refer promptly for ophthalmologic examination mainly to exclude papilledema Measure blood pressure to detect systemic hypertension or hypotension
Migraine is benign unless patient is smoker or is using birth control pills; either increases risk of stroke Transient ischemic attack carries risk of stroke Seizures suggest structural lesion of occipital lobe Poorly controlled systemic hypertension is grave risk to health Papilledema indicates increased intracranial pressure
