Use of magnetic resonance imaging in psychiatry

The authors report four cases in which magnetic resonance imaging (MRI) provided diagnostic information not apparent by X-ray CAT in clinical investigations of patients with neuropsychiatric disorders. The relative capabilities and contraindications for MRI and CAT are reviewed. The authors suggest that MRI is indicated 1) instead of CAT when there is suspicion of neuropathology that is better visualized by MRI because of its type or location and 2) after CAT when an atypical psychiatric symptom or presentation has not been definitively evaluated by means of CAT.