Dynamic CT using an arterial bolus.

Arterial bolus dynamic computed tomography (ABDCT) was performed on 52 patients presenting with intracranial and intraspinal disorders. Rapid sequential ABDCT scans were obtained during selective intraarterial injection of a small bolus of contrast material following conventional angiography. By this method, the local intravascular iodine level was maximized, allowing for improved contrast resolution of central nervous system lesions. Thirty-eight patients had a known diagnosis. In 35 of these, ABDCT was helpful in delineating tumor margins at the base of the skull and demonstrating tumor or arteriovenous malformation vascularity. In 14 patients, the diagnosis was obscure using conventional computed tomography. In eight of these, ABDCT suggested a distinction between infarct, neoplasm, and inflammatory process. In the remaining six, ABDCT was noncontributory.