MR imaging in the evaluation of trauma

Although computed tomography (CT) and radiographs are primary modalities in the evaluation of patients undergoing trauma, the indications for magnetic resonance (MR) imaging in trauma have grown. MR has been most useful in patients with central nervous system or musculoskeletal trauma. In head trauma, MRI is most useful in the evaluation of patients with neurologic deficit greater than that expected from CT findings. MRI is useful in such situations because of its improved sensitivity to nonhemorrhagic and microhemorrhagic lesions as well as posterior fossa pathology. In the spine, MRI provides detailed assessment of the disc space, spinal cord, and ligamentous structures; guiding therapeutic decisions; and offering prognostic information. In the musculoskeletal system, MRI offers a noninvasive means of imaging injuries to the muscles, tendons, ligaments, and cartilage of the knee, shoulder, ankle, and elbow. Additionally, MRI may define a subset of radiographically occult bony injuries.