Steven Lippmann, M.D.

Brain imaging technology improves the practice of psychiatry by better detection and monitoring of neuropathology. Computerized tomography (CT) of the head is fast, widely available, and excellent in assessment of recent trauma cases, but it yields exposure to radiation. Thus, any neonatal and pediatric use is severely limited and recurrent exposure is not desirable. Magnetic resonance imaging (MRI) is more precise and involves no radiation, but it is expensive and cannot be performed on people with certain implanted devices.



In addition to x-ray exposure, CT scans that utilize contrast materials also have risks that include allergic reactions and renal dysfunction. For example, if contrast materials are considered for use in a patient, metformin should be discontinued and hydration assured before contrast materials are administered. CT is good for guiding detection of new, acute hemorrhage under three days old, calcification, and at depiction of bony anatomy. MRI is excellent at very clear, high quality views of brain structures without skull feature interference. Many implanted electronic or metallic devices contraindicate the implementation of MRI. Some people feel claustrophobic when placed into the narrow space of certain MRI devices.

Brain imaging is most likely to be clinically valuable in evaluation of patients with overt clinical signs of encephalopathies, abnormal neurological findings, or other evidence of brain-related neuropathology. In fact, scanning is not often helpful at diagnostic enhancement in cases without specific neurological features present. To avoid complications following the use of electroconvulsive therapy (ECT), pre-treatment imaging helps rule out lesions like brain tumors or infarcts that might cause adverse complications following treatment.

Indication Guidelines: when psychiatrists should order a head scan

• current head injury or new focal neurological findings
• recent or progressive cognitive decline or brain-related visual impairment
• new brain pathology or signs of increased intracranial pressure
• new or changed psychiatric presentations in a person over age 50
• persistent, progressive or recurrent headaches
• selected neoplastic assessments
• selected cases in the first onset of an acute psychiatric illness
• in the pre-ECT workup
• at physician judgment when other indications are overtly noted clinically

Brain imaging can improve diagnostic accuracy and differentiation of psychiatric from neurological conditions. CT scans are recommended in acute trauma cases while MRI is selected for better depiction of anatomical detail and for evaluation of a subacute intracranial bleed that is over 72 hours old.

Scans offer an illustration of intracranial pathology in the evaluation or monitoring of people with a wide variety of psychiatric or neurological presentations and illnesses. Ordered with proper indications, the images are a cost-effective tool.