Use of Brain Images in Neurological Diseases

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Source: Gilman S. N Engl J Med 1998;338:812-819.

In two medical progress articles, gilman usefully describes and discusses the use of brain images in neurological diseases. With the permission of the New England Journal of Medicine and the author, this Table was published from the article. Most of the identified disorders require brain imaging for current standards of immediate care. Those marked by an "x" are optional, and the expense of their performance should be considered carefully against their expected usefulness. Once a diagnostic MRI identifies multiple sclerosis, for example, repeated scans have little value except during commercial drug trials. Similar or greater restraint applies to routine examples of the other optional guidelines. (Dr. Plum is Neurologist-in-Chief, New York Hospital-Cornell Medical Center.)

Table

Preferred Imaging Procedures in Neurologic Diseases

Neurologic Disease Imaging Procedure

Cerebral or cerebellar CT in the first 12-24 hr; MRI after 12-24 ischemic infarctiohr (diffusion-weighted and perfusion-weighted MRI augments the findings, especially in the first 24 hr, and even before 8 hr).

Cerebral or cerebellar CT in the first 24 hr; MRI after 24 hr; hemorrhage MRI and endovascular angiography for suspected arteriovenous malformation.

Transient ischemic attack MRI to identify lacunar or other small lesions; ultrasound studies of the carotid arteries; MRA.

Arteriovenous malformatioCT for acute hemorrhage; MRI and endovascular angiography as early as possible.

Cerebral aneurysm CT for acute subarachnoid hemorrhage; CT angiography or endovascular angiography to identify aneurysm; TCD to detect vasospasms.

Brain tumor MRI without and with injection of contrast material.

Craniocerebral trauma CT initially; MRI after initial assessment and treatment.

Multiple sclerosis MRI without and with injection of contrast material.

Meningitis or encephalitis CT without and with injection of contrast material initially, MRI after initial assessment and treatment.

Cerebral or cerebellar abscess CT without and with injection of contrast material for initial diagnosis or, if stable, MRI. MRI without and with injection of contrast material subsequently.

Granuloma MRI without and with injection of contrast material.

Dementia MRI; PET; SPECT.

Movement disorders MRI; PET.

Neonatal and development Ultrasound in unstable premature disorders neonates; otherwise MRI.

Epilepsy MRI; PET; SPECT.

Headache CT in patients suspected of having structural disorders.

Adapted with permission from Gilman S. N Engl J Med 1998;338:812-819. Copyright 1998 Massachusetts Medical Society. All rights reserved.