title: Noninvasive assessment of the circle of Willis in cerebral ischemia: the potential of CT angiography and contrast-enhanced transcranial color-coded duplexsonography.
abstract: Thirty-four patients with acute hemispheric ischemic strokes underwent both CT angiography and contrast-enhanced transcranial color-coded duplexsonography (TCCD) to study the effectiveness of the combined noninvasive techniques for evaluation of the circle of Willis. In 3/34 patients, CT angiography and contrast-enhanced TCCD demonstrated middle cerebral artery (MCA) occlusion, in 5 others MCA stenosis. A severe posterior cerebral artery stenosis was missed by CT angiography. In 8 patients, contrast-enhanced TCCD failed because of poor bone windows. In these patients, CT angiography was normal. CT angiography and contrast-enhanced TCCD are complementary noninvasive diagnostic tools. Disagreements between the diagnostic findings of these methods still need further evaluation by digital subtraction angiography.
authors.affiliation: Department of Neurology, University of Dresden, Germany. gahn@rcs.urz.tu-dresden.de
authors.forename: G
authors.initials: G
authors.lastname: Gahn
authors.forename: J
authors.initials: J
authors.lastname: Gerber
authors.forename: S
authors.initials: S
authors.lastname: Hallmeyer
authors.forename: H
authors.initials: H
authors.lastname: Reichmann
authors.forename: R
authors.initials: R
authors.lastname: von Kummer
mesh_terms: D000368:Aged; D015901:Angiography, Digital Subtraction; D002545:Brain Ischemia / Q000175:diagnosis*; D002941:Circle of Willis / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008297:Male; D018615:Ultrasonography, Doppler, Color; D018616:Ultrasonography, Doppler, Duplex; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D003287:Contrast Media