Imaging strategies for MR of the brain.

MR has emerged as the imaging modality of choice for the brain in patients presenting with seizures, chronic headaches, progressive neurologic deficits, ataxia, vertigo, hearing loss, visual loss, congenital abnormalities, signs of increased intracranial pressure, dementia, suspected multiple sclerosis, and in the vast majority of other elective neurologic problems. CT should currently be considered the primary imaging modality in patients with acute neurologic deficits (stroke), acute onset of severe headaches, and when fine bone detail is required. Acutely injured patients are more readily studied with CT. The vast majority of patients in whom CT is preferred are seen in emergent situations, frequently in hospital emergency rooms. The effects of trauma beyond the acute stage are best evaluated with MR. In the future, MR is likely to become the procedure of choice in even more clinical situations than at present. A summary of currently recommended primary imaging modalities in various clinical situations is provided in Table 1.