Lit Matters #1: Use of Neuroimaging for Patients with Dizziness in Outpatient Clinics vs Emergency Departments

Head CT has poor sensitivity for posterior fossa stroke in dizzy patients, and neuroimaging for dizziness is common despite a low diagnostic yield. In U.S. claims data, emergency departments image far more often and earlier than outpatient clinics, with MRI driving most of the spending.

Dizziness Neuroimaging in Emergency Care

• Low-yield imaging pattern: Neuroimaging for dizziness was obtained within 6 months in 35% of ED visits versus 15% of outpatient presentations, a large practice gap that raises real value and overuse concerns.
• Same-day ED scanning: ED patients were usually imaged the same day, while clinic patients were scanned around day 10, highlighting how setting strongly shapes both testing intensity and timing.
• CT sensitivity problem: Noncontrast head CT is a weak rule-out test for posterior fossa infarct, with about 16% sensitivity, so a normal scan can falsely reassure clinicians facing possible central vertigo.
• MRI limits and cost: Diffusion-weighted MRI is substantially better for ischemia detection, around 83% for posterior fossa infarct, yet early studies can still miss small strokes and MRI accounts for most spending.
• Who merits concern: Central causes cluster in dizziness with neurologic features such as gait instability, visual symptoms, focal sensory or motor deficits, or sudden hearing loss. We get into the bedside red flags in the episode.
• HINTS exam caution: The HINTS exam can outperform early imaging in the right hands, but misapplication is common outside true acute vestibular syndrome, making indiscriminate use a setup for error.