Cranial computed tomography of patients with malignant melanoma.

Sixty-eight patients with malignant melanoma were examined by CCT and the findings analyzed. Cerebral metastases were detected in 19 patients. Meningiomas were found in three patients, one with neurological symptoms and two without. Typical metastases less than 10 mm in diameter were located superficially in the grey matter, regular, homogenous, hyperdense, with no edema. Extensive peripheral edema was often associated with metastases measuring more than 10 mm. CCT revealed cerebral metastases in 6 (13%) of 46 asymptomatic patients. The metastases measured less than 10 mm in four and less than 20 mm in two of these patients. Scintigraphy was falsely negative in six patients with metastases smaller than 10 mm. Therefore, CCT is the method of choice for screening asymptomatic patients. Angiography may be of value in the differentiation between meningioma and melanoma metastases.