Imaging Recommendations for Patients with Dizziness

Initial Imaging Study

• The American College of Radiology recommends non-contrast head CT as the standard initial neuroimaging study for patients with dizziness when imaging is indicated, as it can quickly rule out life-threatening conditions such as hemorrhage 1, 2, 3.
• Non-contrast CT has a high negative predictive value of approximately 90% for detecting serious pathology, although the diagnostic yield is very low (<1%) 2, 3, 4.

Limitations of CT with Contrast

• There is no relevant literature supporting the use of CT head with IV contrast in the evaluation of isolated dizziness 2, 4, 5.
• CT with contrast does not provide significant additional diagnostic information over non-contrast CT in the setting of isolated dizziness 1, 6.

Alternative Imaging Modalities

• MRI without contrast is more sensitive than CT for detecting posterior fossa lesions and has a slightly higher diagnostic yield (approximately 4%) 2, 5, 8.
• MRI is particularly valuable when there are abnormal neurological findings or when a central cause of vertigo is suspected 8.

Clinical Decision-Making

• For isolated dizziness without other neurological symptoms, non-contrast CT is appropriate as an initial imaging study if imaging is deemed necessary, with a low diagnostic yield (<1%) 2, 3, 5.
• Clinical assessment, including HINTS examination, is crucial in determining the need for imaging in patients with dizziness 5, 8.
• For patients with high vascular risk factors, imaging may be more strongly indicated 8.