RT Journal Article SR Electronic T1 Measurement of Time-to-peak Parameter by Use of a New Standardization Method in Patients with Stenotic or Occlusive Disease of the Carotid Artery JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1056 OP 1061 VO 22 IS 6 A1 Našel, Christian A1 Azizi, Amedeo A1 Wilfort, Andrea A1 Mallek, Reinhold A1 Schindler, Erwin YR 2001 UL http://www.ajnr.org/content/22/6/1056.abstract AB BACKGROUND AND PURPOSE: A quantitative, easily obtained measure of cerebral hemodynamics would be valuable in planning surgical or interventional therapy for patients with stenotic or occlusive disease of the carotid artery. We evaluated the recently introduced standardized time-to-peak variable (stdTTP), obtained with dynamic susceptibility contrast-enhanced MR (DSC-MR) imaging, in different states of stenotic/occlusive carotid artery disease.METHODS: We examined 24 patients with unilateral, high-grade stenosis (85%–95%) of one internal carotid artery (ICA) and 10 patients with stenosis (85%–95%) of one ICA and occlusion of the contralateral ICA. Mean stdTTP was evaluated in the central vascular territories of the anterior, middle, and posterior cerebral arteries and the anterior and posterior border zones and compared with the mean stdTTP values from 36 cerebral hemispheres without hemodynamic impairment.RESULTS: Patients showed no significant prolongation of stdTTP in the central vascular territories compared with the reference group, whereas significant prolongations of stdTTP were measured in the anterior and posterior border zones in patients with ICA disease (ANOVA, P < .05) and were most prominent in higher grades of carotid disease. Hemispheres with hemodynamic impairment always showed a stdTTP > 3.5 s in the border zones.CONCLUSION: The StdTTP quantitatively describes the hemodynamic impairment in cerebral hemispheres supplied by a stenosed or occluded ICA. An stdTTP value of > 3.5 s, as has been postulated, seems to point out hemodynamic impairment.