Magnetic resonance imaging versus computed tomography--which one?

Both magnetic resonance imaging (MRI) and x-ray computed tomography (CT) are essential diagnostic imaging tools in current practice. The main goal of this article is to provide a quick reference guide to help the busy clinician choose which test to obtain first to avoid the need for a second expensive imaging examination. In general, MRI is preferred for examination of the CNS, the spine for disk disease, major joints, and soft tissues of the extremities. CT is preferred for examination of the head and spine after acute trauma and of the chest, abdomen, and pelvis.