Cystic mural nodule in cerebellar hemangioblastoma: CT demonstration.

An example of a form of cystic hemangioblastoma of the cerebellum in which the mural nodule itself showed a central cystic area is presented. Although the precise etiology of the cystic component within hemangioblastoma tumor nodules is not known, it probably results from tumor degeneration. Computed tomography is valuable in identifying this feature, which, if present, is very suggestive of the diagnosis of hemangioblastoma. Other diagnostically useful CT features of hemangioblastoma that were present in this case included location of the mural nodule adjacent to the nearest pial surface, isodensity of the nodule on the preinfusion scan, and very rapid circulation of contrast material through the wall of the nodule, demonstrated by dynamic CT technique.