title: Imaging of cerebrovascular reserve and oxygenation in Moyamoya disease.
abstract: This study aimed to determine whether measurements of cerebrovascular reserve and oxygenation, assessed with spin relaxation rate R2', yield similar information about pathology in pre-operative Moyamoya disease patients, and to assess whether R2' is a better measure of oxygenation than other proposed markers, such as R2* and R2. Twenty-five pre-operative Moyamoya disease patients were scanned at 3.0T with acetazolamide challenge. Cerebral blood flow mapping with multi-delay arterial spin labeling, and R2*, R2, and R2' mapping with Gradient-Echo Sampling of Free Induction Decay and Echo were performed. No baseline cerebral blood flow difference was found between angiographically abnormal and normal regions (49 ± 12 vs. 48 ± 11 mL/100 g/min, p = 0.44). However, baseline R2' differed between these regions (3.2 ± 0.7 vs. 2.9 ± 0.6 s-1, p < 0.001), indicating reduced oxygenation in abnormal regions. Cerebrovascular reserve was lower in angiographically abnormal regions (21 ± 38 vs. 41 ± 26%, p = 0.001). All regions showed trend toward significantly improved oxygenation post-acetazolamide. Regions with poorer cerebrovascular reserve had lower baseline oxygenation (Kendall's τ = -0.24, p = 0.003). A number of angiographically abnormal regions demonstrated preserved cerebrovascular reserve, likely due to the presence of collaterals. Finally, of the concurrently measured relaxation rates, R2' was superior for oxygenation assessment.
authors.affiliation: 1 Department of Radiology, Stanford University, Stanford, CA, USA.|2 Department of Electrical Engineering, Stanford University, Stanford, CA, USA.
authors.forename: Wendy W
authors.initials: WW
authors.lastname: Ni
authors.affiliation: 1 Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Christen
authors.affiliation: 1 Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Jarrett
authors.initials: J
authors.lastname: Rosenberg
authors.affiliation: 3 Division of Diagnostic Imaging and Radiology, Children's National Medical Center, Washington, DC, USA.|4 Department of Pediatrics, George Washington University, Washington, DC, USA.
authors.forename: Zungho
authors.initials: Z
authors.lastname: Zun
authors.affiliation: 1 Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Moseley
authors.affiliation: 1 Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Greg
authors.initials: G
authors.lastname: Zaharchuk
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000098:blood supply* / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Moyamoya; Oxygenation; R2′; cerebrovascular reserve; transverse relaxation