Dynamic computed tomography of the brain.

Dynamic computed tomography (CT) scanning was performed on five normal subjects, 38 patients with cerebrovascular disorder, and 20 patients with brain tumours. It consisted of performing six rapid sequential scans after intravenous bolus injection of iodinated contrast medium. By gamma variate fit technique, five features (corrected first moment, area, peak, time to peak, and per cent terminal height) were obtained from a time-density curve in a region of interest. We compared these features in one side of the brain with those in the corresponding contralateral side and tried to get information about cerebral perfusion. These results showed that by this technique we are able to detect arterial occlusions or Moya moya diseases non-invasively and know earlier and more clearly the re-establishment of circulation in the occluded arteries and of extravasation of contrast medium in ischaemic regions than by conventional CT scanning. In arteriovenous malformations, serial images of dynamic CT scanning demonstrated the anatomical details of the nidus, and the afferent and efferent vessels. We can also identify an exact extent of tumoral invasion of the brain in patients with malignant brain tumor.