Sudden Visual Loss Workup

Updated: May 18, 2016
  • Author: Gino A Farina, MD, FACEP, FAAEM; Chief Editor: Edsel Ing, MD, MPH, FRCSC  more...
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Laboratory Studies

Individualize the evaluation of patients with transient monocular visual loss (TMVL).

Because common causes of TMVL are ischemic, cardiac and cerebrovascular related laboratory studies should be evaluated.

Laboratory studies should include blood counts and coagulation studies.

Obtain erythrocyte sedimentation rate, C-reactive protein level, and platelet count in patients older than 55 years with suspected giant cell arteritis.


Imaging Studies

Treating transient monocular blindness (TMB) and atherosclerosis is important because they increase the risk of stroke.

Noninvasive evaluation of the carotid artery and heart (eg, echocardiography, carotid Doppler) is useful in patients older than 40 years; this evaluation provides information on the degree of stenosis. Noninvasive study of the heart can detect abnormal valves, dyskinetic wall segments, and arrhythmias, all of which predispose to the formation of emboli.

Ulceration is more difficult to detect noninvasively than invasively, so angiography remains the diagnostic standard for detecting carotid atherosclerotic disease.

Fluorescein angiography is helpful for detecting embolic retinal vascular occlusion. The most common embolic particles are cholesterol crystals, which are often small; they disappear rapidly but not without damaging the vessel wall.

Fluorescein angiography may show hyperfluorescent crystals or areas of fluorescein leakage that are caused by crystal-related endothelial damage.


Other Tests

Holter monitoring is the preferred method to screen for intermittent cardiac arrhythmias.

Temporal artery biopsy is performed often to rule out giant cell arteritis. A clinician should perform biopsies frequently. The risk of missing the diagnosis of giant cell arteritis far outweighs the minor inconvenience of this very benign procedure.