Yield of CT angiography and contrast-enhanced MR imaging in patients with dizziness

Dizziness is a common symptom in emergency and outpatient settings. The purpose of our study was to compare the diagnostic and therapeutic efficacy of CTA of the head and neck, contrast-enhanced MR imaging of the brain (CE-MR), and contrast-enhanced MR imaging of the internal auditory canals and temporal bones in patients with isolated dizziness, to determine which of these modalities should be preferred in the evaluation of dizziness. We retrospectively identified patients presenting with dizziness from January 2011 to June 2012 who underwent a CTA, CE-MR, or MRIAC. We excluded patients with signs or symptoms suggestive of other neurologic pathology or a history of an abnormality known to cause dizziness. We calculated the proportion of patients with abnormal findings on a study, tabulated the nature of the abnormality, and reviewed the medical records to determine whether imaging changed management. Two hundred twenty-eight CTAs, 304 CE-MRs, and 266 MRIACs were included. Five patients (2.2%) with CTAs, 4 (1.3%) with CE-MRs, and 4 (1.5%) with MRIACs demonstrated significant findings that related to the history of dizziness or were incidental but judged to be clinically significant. Of these, 3 CTA (1.3%), 2 CE-MR (0.7%), and 3 MRIAC (1.1%) examinations resulted in a change in clinical management. Imaging evaluation of the patient with uncomplicated dizziness is unlikely to identify clinically significant imaging findings and is very unlikely to result in a change in clinical management, with an overall TE of 1.0%. Thus, the routine use of imaging in the evaluation of the patient with dizziness cannot be recommended.