RT Journal Article
SR Electronic
T1 Use of acetazolamide-challenge xenon CT in the assessment of cerebral blood flow dynamics in patients with arteriovenous malformations.
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 441
OP 448
VO 11
IS 3
A1 R W Tarr
A1 D W Johnson
A1 M Rutigliano
A1 S T Hecht
A1 S Pentheny
A1 C A Jungreis
A1 J A Horton
A1 H Yonas
YR 1990
UL http://www.ajnr.org/content/11/3/441.abstract
AB Arteriovenous malformations (AVMs) may cause symptoms related to a reduction of cerebral blood flow (CBF) to surrounding brain parenchyma. To evaluate this compromise of hemodynamic reserve (commonly referred to as steal phenomenon), we used acetazolamide challenge and stable-xenon CT (Xe/CT). Baseline Xe/CT studies in 13 patients with AVMs were followed by an acetazolamide challenge to the vascular reserve. Blood flow maps were quantitated by using region-of-interest (ROI) software. ROI findings were categorized into four groups on the basis of the presence or absence of normal baseline CBF and presence or absence of normal augmentation of CBF. ROIs were designated as near site (within the vascular territory supplying the AVM) or far site (outside the vascular territory supplying the AVM). One patient had a normal baseline and normal augmentation of CBF (group 1). The other patients had a combination of one or more of the other three categories. Ten patients had parenchymal areas that exhibited either a normal or low baseline CBF with decreased augmentation; both conditions were interpreted as decreased vascular reserve (groups 2 and 3). Eleven patients had parenchymal areas that showed a low baseline CBF and normal augmentation with acetazolamide (group 4), interpreted as having a decreased demand for CBF but having a normal vascular reserve. Decreased vascular reserve was found in 27% of the nearsite areas and 17% of the far-site areas. No patients had only far-site abnormal vascular reserve. We believe that compromised vascular reserve can best be evaluated with a challenge study, such as this acetazolamide-challenge Xe/CT study.(ABSTRACT TRUNCATED AT 250 WORDS)