title: Quantitative cerebral perfusion MRI and CO2 reactivity measurements in patients with symptomatic internal carotid artery occlusion.
abstract: Quantitative perfusion MRI is a promising new technique capable of offering information on cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT). However, it is still unclear how these perfusion parameters relate to the underlying physiological indicators and how they compare to conventional techniques. The purpose of this study was to investigate how quantitative perfusion MRI is related to the cerebrovascular reactivity as measured by transcranial Doppler ultrasonography (TCD) in combination with a CO2 stimulus in patients with a symptomatic occlusion of the internal carotid artery (ICA). Thirty-nine patients with transient or minor disabling retinal or hemispheric ischemic symptoms and an occlusion of the ICA underwent quantitative perfusion MRI and CO2 reactivity measurements by TCD. Perfusion parameters were correlated with cerebrovascular reactivity measurements and compared with measurements of control subjects. The results of this study show a negative correlation between the cerebrovascular reactivity and the time to bolus peak (TBP) both for gray (r = -0.26, P = 0.035) and white matter (r = -0.28, P = 0.026). No correlation between resting CBV, CBF, or MTT and cerebrovascular reactivity was found. Our results indicate that an increase in TBP reflects a poor development of collateral flow, which is supported by a relatively low CO2 reactivity in these patients.
authors.affiliation: Image Sciences Institute, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. thijs@isi.uu.nl
authors.forename: M J P
authors.initials: MJ
authors.lastname: van Osch
authors.forename: D R
authors.initials: DR
authors.lastname: Rutgers
authors.forename: E P A
authors.initials: EP
authors.lastname: Vonken
authors.forename: A C
authors.initials: AC
authors.lastname: van Huffelen
authors.forename: C J M
authors.initials: CJ
authors.lastname: Klijn
authors.forename: C J G
authors.initials: CJ
authors.lastname: Bakker
authors.forename: J
authors.initials: J
authors.lastname: van der Grond
mesh_terms: D000328:Adult; D000368:Aged; D001810:Blood Volume / Q000502:physiology; D002152:Calorimetry, Differential Scanning; D002245:Carbon Dioxide / Q000378:metabolism*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D002245:Carbon Dioxide