Vascular space occupancy (VASO) cerebral blood volume‐weighted MRI identifies hemodynamic impairment in patients with carotid artery disease
Open Access
- 25 February 2009
- journal article
- research article
- Published by Wiley in Journal of Magnetic Resonance Imaging
- Vol. 29 (3), 718-724
- https://doi.org/10.1002/jmri.21667
Abstract
Purpose To assess the role of vascular space occupancy (VASO) magnetic resonance imaging (MRI), a noninvasive cerebral blood volume (CBV)‐weighted technique, for evaluating CBV reactivity in patients with internal carotid artery (ICA) stenosis. Materials and Methods VASO reactivity, defined as a signal change in response to hypercapnic stimulus (4‐second exhale, 14‐second breath‐hold), was measured in the left and right ICA flow territories in patients (n = 10) with varying degrees of unilateral and bilateral ICA stenosis and in healthy volunteers (n = 10). Results Percent VASO reactivity was more negative (P < 0.01) bilaterally in patients (ipsilateral: −3.6 ± 1.5%; contralateral: −3.4 ± 1.2%) compared with age‐matched controls (left: −1.9 ± 0.6%; right: −1.9 ± 0.8%). Owing to the nature of the VASO contrast mechanism, this more negative VASO reactivity was attributed to autoregulatory CBV effects in patients. A postbreath‐hold overshoot, which was absent in healthy volunteers, was observed unilaterally in a subset of patients. Conclusion More negative VASO reactivity was observed in patients with ICA stenosis and may be a marker of autoregulatory effects. Furthermore, the postbreath‐hold overshoot observed in patients is consistent with compensatory microvascular vasoconstriction and may be a marker of hemodynamic impairment. Based on the results of this feasibility study, VASO should be useful for identifying CBV adjustments in patients with steno‐occlusive disease of the ICA. J. Magn. Reson. Imaging 2009;29:718–724.Keywords
This publication has 19 references indexed in Scilit:
- Hemodynamic Changes after Visual Stimulation and Breath Holding Provide Evidence for an Uncoupling of Cerebral Blood Flow and Volume from Oxygen MetabolismJournal of Cerebral Blood Flow & Metabolism, 2008
- VASO‐based calculations of CBV change: Accounting for the dynamic CSF volumeMagnetic Resonance in Medicine, 2008
- Evaluation of human brain tumor heterogeneity using multiple T1‐based MRI signal weighting approachesMagnetic Resonance in Medicine, 2008
- Applications and limitations of whole-brain MAGIC VASO functional imagingMagnetic Resonance in Medicine, 2007
- Theoretical and experimental investigation of the VASO contrast mechanismMagnetic Resonance in Medicine, 2006
- Experimental measurement of extravascular parenchymal BOLD effects and tissue oxygen extraction fractions using multi‐echo VASO fMRI at 1.5 and 3.0 TMagnetic Resonance in Medicine, 2005
- Collateral CirculationStroke, 2003
- Angiographically Defined Collateral Circulation and Risk of Stroke in Patients With Severe Carotid Artery StenosisStroke, 2000
- Role of impaired CO2 reactivity in the diagnosis of cerebral low flow infarcts.Journal of Neurology, Neurosurgery & Psychiatry, 1994
- Interobserver agreement for the assessment of handicap in stroke patients.Stroke, 1989