Medullary arteries in cerebral neoplasms.

In cerebral neoplasms, the visibility of long segments of the medullary arteries indicates white matter involvement by infiltrative or compressive disturbances. Relating the mass effect to the position of the medullary arteries should allow for differentiating a primary from a secondary avascular neoplasm. When the neoplasm is vascular, the presence of neovascularity with the medullary arteries is likely to signify a high degree of anaplasia.