Characterization of intracranial neoplasms by CT and intraoperative sonography.

Twenty-one adult male patients with 24 intracranial neoplasms were studied with intraoperative sonography and preoperative computed tomography (CT). Both methods defined the lesions, but the characteristic appearances were different. Sonography was more effective than CT in determining whether a lesion was cystic, with or without septations, or solid. Most importantly, sonography was an intraoperative localizing tool, which required a surgically created cranial defect. CT excelled in defining the ancillary components of an intracranial neoplasm, such as surrounding edema and details evident with contrast enhancement, but it had no capability for intraoperative use.