Less than 7.1% of patients presenting to the emergency department with dizziness and 6.4% complaining of syncope or near-syncope benefited from head CT say researchers at Kaiser Foundation Hospital in Honolulu. The use of head CT as part of a screening examination, rather than as a diagnostic tool, likely stems from increased pressure on emergency physicians to evaluate and differentiate between benign and life-threatening causes of dizziness and syncope.

Head CT scans are not recommended unless the loss of consciousness is suspected not to be syncope. Using CT in cases of uncomplicated syncope should be avoided unless physical or historical features of CNS dysfunction are present. However, use of head CT scans obtained to evaluate patients with syncope in the emergency department appears to be a common practice with little evidence of benefit.

"Most patients with mild symptoms of dizziness or syncope do not require a head CT," says Myles M. Mitsunaga, principal investigator and resident at the John A. Burns School of Medicine, University of Hawaii. "If a careful history and physical examination do not find persistent neurologic signs, then a follow-up clinic visit the next day may be all that is necessary."

The study, "Head CT Scans in the Emergency Department for Syncope and Dizziness," appears in the January 2015 issue of the American Journal of Roentgenology.