title: The Effects of Acetazolamide on the Evaluation of Cerebral Hemodynamics and Functional Connectivity Using Blood Oxygen Level-Dependent MR Imaging in Patients with Chronic Steno-Occlusive Disease of the Anterior Circulation.
abstract: Measuring cerebrovascular reactivity with the use of vasodilatory stimuli, such as acetazolamide, is useful for chronic cerebrovascular steno-occlusive disease. The purpose of this study was to evaluate the effects of acetazolamide on the assessment of hemodynamic impairment and functional connectivity by using noninvasive resting-state blood oxygen level-dependent MR imaging.
  
  
  
  A 20-minute resting-state blood oxygen level-dependent MR imaging scan was acquired with infusion of acetazolamide starting at 5 minutes after scan initiation. A recently developed temporal-shift analysis technique was applied on blood oxygen level-dependent MR imaging data before and after acetazolamide infusion to identify regions with hemodynamic impairment, and the results were compared by using contrast agent-based DSC perfusion imaging as the reference standard. Functional connectivity was compared with and without correction on the signal by using information from temporal-shift analysis, before and after acetazolamide infusion.
  
  
  
  Visually, temporal-shift analysis of blood oxygen level-dependent MR imaging data identified regions with compromised hemodynamics as defined by DSC, though performance deteriorated in patients with bilateral disease. The Dice similarity coefficient between temporal-shift and DSC maps was higher before (0.487 ± 0.150 by using the superior sagittal sinus signal as a reference for temporal-shift analysis) compared with after acetazolamide administration (0.384 ± 0.107) (P = .006, repeated-measures ANOVA). Functional connectivity analysis with temporal-shift correction identified brain network nodes that were otherwise missed. The accuracy of functional connectivity assessment decreased after acetazolamide administration (P = .015 for default mode network, repeated-measures ANOVA).
  
  
  
  Temporal-shift analysis of blood oxygen level-dependent MR imaging can identify brain regions with hemodynamic compromise in relation to DSC among patients with chronic cerebrovascular disease. The use of acetazolamide reduces the accuracy of temporal-shift analysis and network connectivity evaluation.
authors.affiliation: From the Departments of Radiology and Imaging Sciences (J.W., S.D., J.A., D.Q.).
authors.forename: J
authors.identifier: 0000-0002-7562-2352
authors.initials: J
authors.lastname: Wu
authors.affiliation: From the Departments of Radiology and Imaging Sciences (J.W., S.D., J.A., D.Q.).
authors.forename: S
authors.identifier: 0000-0002-3141-1094
authors.initials: S
authors.lastname: Dehkharghani
authors.affiliation: Neurology (F.N.), Emory University School of Medicine, Atlanta, Georgia.
authors.forename: F
authors.identifier: 0000-0003-1710-9881
authors.initials: F
authors.lastname: Nahab
authors.affiliation: From the Departments of Radiology and Imaging Sciences (J.W., S.D., J.A., D.Q.).
authors.forename: J
authors.identifier: 0000-0002-5274-1105
authors.initials: J
authors.lastname: Allen
authors.affiliation: From the Departments of Radiology and Imaging Sciences (J.W., S.D., J.A., D.Q.) dqiu3@emory.edu.
authors.forename: D
authors.identifier: 0000-0001-8375-1755
authors.initials: D
authors.lastname: Qiu
mesh_terms: D000086:Acetazolamide / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D055420:Perfusion Imaging / Q000379:methods; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D000086:Acetazolamide; D010100:Oxygen