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Sur S, Lin Z, Li Y, Yasar S, Rosenberg PB, Moghekar A, Hou X, Jiang D, Kalyani RR, Hazel K, Pottanat G, Xu C, Pillai JJ, Liu P, Albert M, Lu H. CO 2 cerebrovascular reactivity measured with CBF-MRI in older individuals: Association with cognition, physical function, amyloid and tau proteins. J Cereb Blood Flow Metab 2024; 44:1618-1628. [PMID: 38489769 DOI: 10.1177/0271678x241240582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
Vascular pathology is the second leading cause of cognitive impairment and represents a major contributing factor in mixed dementia. However, biomarkers for vascular cognitive impairment and dementia (VCID) are under-developed. Here we aimed to investigate the potential role of CO2 Cerebrovascular Reactivity (CVR) measured with phase-contrast quantitative flow MRI in cognitive impairment and dementia. Forty-five (69 ± 7 years) impaired (37 mild-cognitive-impairment and 8 mild-dementia by syndromic diagnosis) and 22 cognitively-healthy-control (HC) participants were recruited and scanned on a 3 T MRI. Biomarkers of AD pathology were measured in cerebrospinal fluid. We found that CBF-CVR was lower (p = 0.027) in the impaired (mean±SE, 3.70 ± 0.15%/mmHg) relative to HC (4.28 ± 0.21%/mmHg). After adjusting for AD pathological markers (Aβ42/40, total tau, and Aβ42/p-tau181), higher CBF-CVR was associated with better cognitive performance, including Montreal Cognitive Assessment, MoCA (p = 0.001), composite cognitive score (p = 0.047), and language (p = 0.004). Higher CBF-CVR was also associated with better physical function, including gait-speed (p = 0.006) and time for five chair-stands (p = 0.049). CBF-CVR was additionally related to the Clinical-Dementia-Rating, CDR, including global CDR (p = 0.026) and CDR Sum-of-Boxes (p = 0.015). CBF-CVR was inversely associated with hemoglobin A1C level (p = 0.017). In summary, CBF-CVR measured with phase-contrast MRI shows associations with cognitive performance, physical function, and disease-severity, independent of AD pathological markers.
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Affiliation(s)
- Sandeepa Sur
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Zixuan Lin
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Yang Li
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Sevil Yasar
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Paul B Rosenberg
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Abhay Moghekar
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Xirui Hou
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Dengrong Jiang
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Rita R Kalyani
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Kaisha Hazel
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - George Pottanat
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Cuimei Xu
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Jay J Pillai
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Division of Neuroradiology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Peiying Liu
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center, Kennedy Krieger Institute, Baltimore, MD, USA
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Zvolanek KM, Moore JE, Jarvis K, Moum SJ, Bright MG. Macrovascular blood flow and microvascular cerebrovascular reactivity are regionally coupled in adolescence. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.590312. [PMID: 38746187 PMCID: PMC11092525 DOI: 10.1101/2024.04.26.590312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Cerebrovascular imaging assessments are particularly challenging in adolescent cohorts, where not all modalities are appropriate, and rapid brain maturation alters hemodynamics at both macro- and microvascular scales. In a preliminary sample of healthy adolescents (n=12, 8-25 years), we investigated relationships between 4D flow MRI-derived blood velocity and blood flow in bilateral anterior, middle, and posterior cerebral arteries and BOLD cerebrovascular reactivity in associated vascular territories. As hypothesized, higher velocities in large arteries are associated with an earlier response to a vasodilatory stimulus (cerebrovascular reactivity delay) in the downstream territory. Higher blood flow through these arteries is associated with a larger BOLD response to a vasodilatory stimulus (cerebrovascular reactivity amplitude) in the associated territory. These trends are consistent in a case study of adult moyamoya disease. In our small adolescent cohort, macrovascular-microvascular relationships for velocity/delay and flow/CVR change with age, though underlying mechanisms are unclear. Our work emphasizes the need to better characterize this key stage of human brain development, when cerebrovascular hemodynamics are changing, and standard imaging methods offer limited insight into these processes. We provide important normative data for future comparisons in pathology, where combining macro- and microvascular assessments may better help us prevent, stratify, and treat cerebrovascular disease.
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Han C, Richerson WT, Garza M, Rodeghier M, Mishra M, Davis LT, Fusco M, Chitale R, Shiino S, Jordan LC, Donahue MJ. Cerebrovascular reactivity dispersion as a new biomarker of recent stroke symptomatology in moyamoya. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.02.27.24303346. [PMID: 38463978 PMCID: PMC10925366 DOI: 10.1101/2024.02.27.24303346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Background Moyamoya disease (MMD) is a non-atherosclerotic intracranial steno-occlusive condition placing patients at high risk for ischemic stroke. Direct and indirect surgical revascularization can improve blood flow in MMD; however, randomized trials demonstrating efficacy have not been performed and biomarkers of parenchymal hemodynamic impairment are needed to triage patients for interventions and evaluate post-surgical efficacy. We test the hypothesis that hypercapnia-induced maximum cerebrovascular reactivity (CVR MAX ) and the more novel indicator cerebrovascular reactivity (CVR) response time (CVR DELAY ), both assessed from time-regression analyses of non-invasive hypercapnic imaging, correlate with recent focal ischemic symptoms. Methods Hypercapnic reactivity medical resonance imaging (blood oxygenation level-dependent; echo time=35ms; spatial resolution=3.5×3.5×3.5mm) and catheter angiography assessments of cortical reserve capacity and vascular patency, respectively, in MMD participants (n=73) were performed in sequence. Time regression analyses were applied to quantify CVR MAX and CVR DELAY . Symptomatology information for each hemisphere (n=109) was categorized into symptomatic (ischemic symptoms within six months) or asymptomatic (no history of ischemic symptoms) and logistic regression analysis assessed the association of CVR metrics with ischemic symptoms after controlling for age and sex. Results Symptomatic hemispheres displayed lengthened CVR DELAY (p<0.001), which was more discriminatory between hemispheres than CVR MAX (p=0.037). CVR DELAY (p<0.001), but not CVR MAX (p=0.127), was found to be sensitively related to age in asymptomatic tissue (0.33-unit increase/year); age-dependent normative ranges are presented to enable quantitative assessment of patient-specific impairment. Furthermore, the area under the receiver operating characteristic curves shows that CVR DELAY predicts ischemic symptoms (p<0.001), whereas CVR MAX does not (p=0.056). Conclusion Findings support that CVR metrics are uniquely altered in hemispheres with recent ischemic symptoms, motivating the investigation of CVR as a surrogate of ischemic symptomatology and treatment efficacy.
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Han C, Waddle S, Garza M, Davis LT, Eisma JJ, Fusco M, Chitale R, Custer C, McKnight CD, Jordan LC, Donahue MJ. Choroid plexus vascular reactivity in moyamoya: Implications for choroid plexus regulation in ischemic stress. J Neuroimaging 2024; 34:152-162. [PMID: 37885135 PMCID: PMC10842133 DOI: 10.1111/jon.13161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/08/2023] [Accepted: 10/02/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND AND PURPOSE Choroid plexus (ChP) hyperemia has been observed in patients with intracranial vasculopathy and to reduce following successful surgical revascularization. This observation may be attributable to impaired vascular reserve of the ChP or other factors, such as the ChP responding to circulating markers of stress. We extend this work to test the hypothesis that vascular reserve of the ChP is unrelated to intracranial vasculopathy. METHODS We performed hypercapnic reactivity (blood oxygenation level-dependent; echo time = 35 ms; spatial resolution = 3.5 × 3.5 × 3.5 mm, repetition time = 2000 ms) and catheter angiography assessments of ChP reserve capacity and vascular patency in moyamoya patients (n = 53) with and without prior surgical revascularization. Time regression analyses quantified maximum cerebrovascular reactivity and reactivity delay time in ChP and cortical flow territories of major intracranial vessels with steno-occlusion graded as <70%, 70%-99%, and occlusion using Warfarin-Aspirin-Symptomatic-Intracranial-Disease stenosis grading criteria. Analysis of variance (significance: two-sided Bonferroni-corrected p < .05) was applied to evaluate cortical and ChP reactivity, after accounting for end-tidal carbon dioxide change, for differing vasculopathy categories. RESULTS In patients without prior revascularization, arterial vasculopathy was associated with reduced cortical reactivity and lengthened reactivity delay (p ≤ .01), as expected. Regardless of surgical history, the ChP reactivity metrics were not significantly related to the degree of proximal stenosis, consistent with ChP reactivity being largely preserved in this population. CONCLUSIONS Findings are consistent with ChP reactivity in moyamoya not being dependent on observed vasculopathy. Future work may investigate the extent to which ChP hyperemia in chronic ischemia reflects circulating markers of glial or ischemic stress.
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Affiliation(s)
- Caleb Han
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Spencer Waddle
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Maria Garza
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - L. Taylor Davis
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jarrod J. Eisma
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Matthew Fusco
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rohan Chitale
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea Custer
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Colin D. McKnight
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lori C. Jordan
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J. Donahue
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
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Woodward OB, Driver I, Schwarz ST, Hart E, Wise R. Assessment of brainstem function and haemodynamics by MRI: challenges and clinical prospects. Br J Radiol 2023; 96:20220940. [PMID: 37721043 PMCID: PMC10607409 DOI: 10.1259/bjr.20220940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 04/25/2023] [Accepted: 05/24/2023] [Indexed: 09/19/2023] Open
Abstract
MRI offers techniques for non-invasively measuring a range of aspects of brain tissue function. Blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) is widely used to assess neural activity, based on the brain's haemodynamic response, while arterial spin labelling (ASL) MRI is a non-invasive method of quantitatively mapping cerebral perfusion. Both techniques can be applied to measure cerebrovascular reactivity (CVR), an important marker of the health of the cerebrovascular system. BOLD, ASL and CVR have been applied to study a variety of disease processes and are already used in certain clinical circumstances. The brainstem is a critical component of the central nervous system and is implicated in a variety of disease processes. However, its function is difficult to study using MRI because of its small size and susceptibility to physiological noise. In this article, we review the physical and biological underpinnings of BOLD and ASL and their application to measure CVR, discuss the challenges associated with applying them to the brainstem and the opportunities for brainstem MRI in the research and clinical settings. With further optimisation, functional MRI techniques could feasibly be used to assess brainstem haemodynamics and neural activity in the clinical setting.
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Affiliation(s)
- Owen Bleddyn Woodward
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, United Kingdom
| | - Ian Driver
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, United Kingdom
| | | | - Emma Hart
- University of Bristol, Bristol, United Kingdom
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Agarwal S, Welker KM, Black DF, Little JT, DeLone DR, Messina SA, Passe TJ, Bettegowda C, Pillai JJ. Detection and Mitigation of Neurovascular Uncoupling in Brain Gliomas. Cancers (Basel) 2023; 15:4473. [PMID: 37760443 PMCID: PMC10527022 DOI: 10.3390/cancers15184473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/28/2023] [Accepted: 09/01/2023] [Indexed: 09/29/2023] Open
Abstract
Functional magnetic resonance imaging (fMRI) with blood oxygen level-dependent (BOLD) technique is useful for preoperative mapping of brain functional networks in tumor patients, providing reliable in vivo detection of eloquent cortex to help reduce the risk of postsurgical morbidity. BOLD task-based fMRI (tb-fMRI) is the most often used noninvasive method that can reliably map cortical networks, including those associated with sensorimotor, language, and visual functions. BOLD resting-state fMRI (rs-fMRI) is emerging as a promising ancillary tool for visualization of diverse functional networks. Although fMRI is a powerful tool that can be used as an adjunct for brain tumor surgery planning, it has some constraints that should be taken into consideration for proper clinical interpretation. BOLD fMRI interpretation may be limited by neurovascular uncoupling (NVU) induced by brain tumors. Cerebrovascular reactivity (CVR) mapping obtained using breath-hold methods is an effective method for evaluating NVU potential.
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Affiliation(s)
- Shruti Agarwal
- Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA;
| | - Kirk M. Welker
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - David F. Black
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - Jason T. Little
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - David R. DeLone
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - Steven A. Messina
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - Theodore J. Passe
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
| | - Chetan Bettegowda
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA;
| | - Jay J. Pillai
- Division of Neuroradiology, Department of Radiology, Mayo Clinic Rochester & Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA; (K.M.W.); (D.F.B.); (J.T.L.); (D.R.D.); (S.A.M.); (T.J.P.)
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA;
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Gullapalli P, Fossati N, Stamenkovic D, Haque M, Cattano D. Tale of Two Cities: narrative review of oxygen. F1000Res 2023; 12:246. [PMID: 37224313 PMCID: PMC10189297 DOI: 10.12688/f1000research.130592.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/05/2023] [Indexed: 05/26/2023] Open
Abstract
The human brain contributes 2% of the body weight yet receives 15% of cardiac output and demands a constant supply of oxygen (O 2) and nutrients to meet its metabolic needs. Cerebral autoregulation is responsible for maintaining a constant cerebral blood flow that provides the supply of oxygen and maintains the energy storage capacity. We selected oxygen administration-related studies published between 1975-2021 that included meta-analysis, original research, commentaries, editorial, and review articles. In the present narrative review, several important aspects of the oxygen effects on brain tissues and cerebral autoregulation are discussed, as well the role of exogenous O 2 administration in patients with chronic ischemic cerebrovascular disease: We aimed to revisit the utility of O 2 administration in pathophysiological situations whether or not being advantageous. Indeed, a compelling clinical and experimental body of evidence questions the utility of routine oxygen administration in acute and post-recovery brain ischemia, as evident by studies in neurophysiology imaging. While O 2 is still part of common clinical practice, it remains unclear whether its routine use is safe.
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Affiliation(s)
- Pranathi Gullapalli
- Department of Anesthesiology, McGovern Medical School UTHealth, Hosuton, USA
| | - Nicoletta Fossati
- Department of Anaesthesia, St George’s Hospital and Medical School, London, UK
| | | | - Muhammad Haque
- Department of Neurology, McGovern Medical School UTHealth, Houston, USA
| | - Davide Cattano
- Department of Anesthesiology, McGovern Medical School UTHealth, Hosuton, USA
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Lindner T, Bolar DS, Achten E, Barkhof F, Bastos-Leite AJ, Detre JA, Golay X, Günther M, Wang DJJ, Haller S, Ingala S, Jäger HR, Jahng GH, Juttukonda MR, Keil VC, Kimura H, Ho ML, Lequin M, Lou X, Petr J, Pinter N, Pizzini FB, Smits M, Sokolska M, Zaharchuk G, Mutsaerts HJMM. Current state and guidance on arterial spin labeling perfusion MRI in clinical neuroimaging. Magn Reson Med 2023; 89:2024-2047. [PMID: 36695294 PMCID: PMC10914350 DOI: 10.1002/mrm.29572] [Citation(s) in RCA: 42] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 01/26/2023]
Abstract
This article focuses on clinical applications of arterial spin labeling (ASL) and is part of a wider effort from the International Society for Magnetic Resonance in Medicine (ISMRM) Perfusion Study Group to update and expand on the recommendations provided in the 2015 ASL consensus paper. Although the 2015 consensus paper provided general guidelines for clinical applications of ASL MRI, there was a lack of guidance on disease-specific parameters. Since that time, the clinical availability and clinical demand for ASL MRI has increased. This position paper provides guidance on using ASL in specific clinical scenarios, including acute ischemic stroke and steno-occlusive disease, arteriovenous malformations and fistulas, brain tumors, neurodegenerative disease, seizures/epilepsy, and pediatric neuroradiology applications, focusing on disease-specific considerations for sequence optimization and interpretation. We present several neuroradiological applications in which ASL provides unique information essential for making the diagnosis. This guidance is intended for anyone interested in using ASL in a routine clinical setting (i.e., on a single-subject basis rather than in cohort studies) building on the previous ASL consensus review.
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Affiliation(s)
- Thomas Lindner
- Department of Diagnostic and Interventional Neuroradiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Divya S. Bolar
- Center for Functional Magnetic Resonance Imaging, Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Eric Achten
- Department of Radiology and Nuclear Medicine, Ghent University, Ghent, Belgium
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands; Queen Square Institute of Neurology and Centre for Medical Image Computing, University College London, UK
| | | | - John A. Detre
- Department of Neurology, University of Pennsylvania, Philadelphia PA USA
| | - Xavier Golay
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Matthias Günther
- (1) University Bremen, Germany; (2) Fraunhofer MEVIS, Bremen, Germany; (3) mediri GmbH, Heidelberg, Germany
| | - Danny JJ Wang
- Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles CA USA
| | - Sven Haller
- (1) CIMC - Centre d’Imagerie Médicale de Cornavin, Place de Cornavin 18, 1201 Genève 1201 Genève (2) Department of Surgical Sciences, Radiology, Uppsala University, Uppsala, Sweden (3) Faculty of Medicine of the University of Geneva, Switzerland. Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, P. R. China
| | - Silvia Ingala
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Hans R Jäger
- UCL Queen Square Institute of Neuroradiology, University College London, London, UK
| | - Geon-Ho Jahng
- Department of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Meher R. Juttukonda
- (1) Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown MA USA (2) Department of Radiology, Harvard Medical School, Boston MA USA
| | - Vera C. Keil
- Department of Radiology and Nuclear Medicine, Cancer Center Amsterdam, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Hirohiko Kimura
- Department of Radiology, Faculty of Medical sciences, University of Fukui, Fukui, JAPAN
| | - Mai-Lan Ho
- Nationwide Children’s Hospital and The Ohio State University, Columbus, OH, USA
| | - Maarten Lequin
- Division Imaging & Oncology, Department of Radiology & Nuclear Medicine | University Medical Center Utrecht & Princess Máxima Center for Pediatric Oncology, Utrecht, The Netherlands
| | - Xin Lou
- Department of Radiology, Chinese PLA General Hospital, Beijing, China
| | - Jan Petr
- (1) Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany (2) Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Nandor Pinter
- Dent Neurologic Institute, Buffalo, NY, USA. University at Buffalo Neurosurgery, Buffalo, NY, USA
| | - Francesca B. Pizzini
- Radiology Institute, Dept. of Diagnostic and Public Health, University of Verona, Verona, Italy
| | - Marion Smits
- (1) Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands (2) The Brain Tumour Centre, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Magdalena Sokolska
- Department of Medical Physics and Biomedical Engineering University College London Hospitals NHS Foundation Trust, UK
| | | | - Henk JMM Mutsaerts
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands
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Zvolanek KM, Moia S, Dean JN, Stickland RC, Caballero-Gaudes C, Bright MG. Comparing end-tidal CO 2, respiration volume per time (RVT), and average gray matter signal for mapping cerebrovascular reactivity amplitude and delay with breath-hold task BOLD fMRI. Neuroimage 2023; 272:120038. [PMID: 36958618 DOI: 10.1016/j.neuroimage.2023.120038] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/27/2023] [Accepted: 03/14/2023] [Indexed: 03/25/2023] Open
Abstract
Cerebrovascular reactivity (CVR), defined as the cerebral blood flow response to a vasoactive stimulus, is an imaging biomarker with demonstrated utility in a range of diseases and in typical development and aging processes. A robust and widely implemented method to map CVR involves using a breath-hold task during a BOLD fMRI scan. Recording end-tidal CO2 (PETCO2) changes during the breath-hold task is recommended to be used as a reference signal for modeling CVR amplitude in standard units (%BOLD/mmHg) and CVR delay in seconds. However, obtaining reliable PETCO2 recordings requires equipment and task compliance that may not be achievable in all settings. To address this challenge, we investigated two alternative reference signals to map CVR amplitude and delay in a lagged general linear model (lagged-GLM) framework: respiration volume per time (RVT) and average gray matter BOLD response (GM-BOLD). In 8 healthy adults with multiple scan sessions, we compare spatial agreement of CVR maps from RVT and GM-BOLD to those generated with PETCO2. We define a threshold to determine whether a PETCO2 recording has "sufficient" quality for CVR mapping and perform these comparisons in 16 datasets with sufficient PETCO2 and 6 datasets with insufficient PETCO2. When PETCO2 quality is sufficient, both RVT and GM-BOLD produce CVR amplitude maps that are nearly identical to those from PETCO2 (after accounting for differences in scale), with the caveat they are not in standard units to facilitate between-group comparisons. CVR delays are comparable to PETCO2 with an RVT regressor but may be underestimated with the average GM-BOLD regressor. Importantly, when PETCO2 quality is insufficient, RVT and GM-BOLD CVR recover reasonable CVR amplitude and delay maps, provided the participant attempted the breath-hold task. Therefore, our framework offers a solution for achieving high quality CVR maps in both retrospective and prospective studies where sufficient PETCO2 recordings are not available and especially in populations where obtaining reliable measurements is a known challenge (e.g., children). Our results have the potential to improve the accessibility of CVR mapping and to increase the prevalence of this promising metric of vascular health.
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Affiliation(s)
- Kristina M Zvolanek
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA.
| | - Stefano Moia
- Basque Center on Cognition, Brain and Language, Donostia, Gipuzkoa, Spain; Medical Imaging Processing Lab (MIP:Lab), Neuro-X institute, EPFL, Geneva, Switzerland
| | - Joshua N Dean
- Department of Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA
| | - Rachael C Stickland
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Molly G Bright
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA
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Wang C, Reid G, Mackay CE, Hayes G, Bulte DP, Suri S. A Systematic Review of the Association Between Dementia Risk Factors and Cerebrovascular Reactivity. Neurosci Biobehav Rev 2023; 148:105140. [PMID: 36944391 DOI: 10.1016/j.neubiorev.2023.105140] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 02/15/2023] [Accepted: 03/15/2023] [Indexed: 03/23/2023]
Abstract
Cumulative evidence suggests that impaired cerebrovascular reactivity (CVR), a regulatory response critical for maintaining neuronal health, is amongst the earliest pathological changes in dementia. However, we know little about how CVR is affected by dementia risk, prior to disease onset. Understanding this relationship would improve our knowledge of disease pathways and help inform preventative interventions. This systematic review investigates 59 studies examining how CVR (measured by magnetic resonance imaging) is affected by modifiable, non-modifiable, and clinical risk factors for dementia. We report that non-modifiable risk (older age and apolipoprotein ε4), some modifiable factors (diabetes, traumatic brain injury, hypertension) and some clinical factors (stroke, carotid artery occlusion, stenosis) were consistently associated with reduced CVR. We also note a lack of conclusive evidence on how other behavioural factors such as physical inactivity, obesity, or depression, affect CVR. This review explores the biological mechanisms underpinning these brain- behaviour associations, highlights evident gaps in the literature, and identifies the risk factors that could be managed to preserve CVR in an effort to prevent dementia.
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Affiliation(s)
- Congxiyu Wang
- Department of Psychiatry, University of Oxford, UK; Wellcome Centre for Integrative Neuroimaging, University of Oxford, UK
| | - Graham Reid
- Department of Psychiatry, University of Oxford, UK; Department of Experimental Psychology, University of Oxford, UK
| | - Clare E Mackay
- Department of Psychiatry, University of Oxford, UK; Wellcome Centre for Integrative Neuroimaging, University of Oxford, UK
| | - Genevieve Hayes
- Institute of Biomedical Engineering, University of Oxford, UK
| | - Daniel P Bulte
- Institute of Biomedical Engineering, University of Oxford, UK
| | - Sana Suri
- Department of Psychiatry, University of Oxford, UK; Wellcome Centre for Integrative Neuroimaging, University of Oxford, UK.
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11
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Waddle S, Garza M, Davis LT, Chitale R, Fusco M, Lee C, Patel NJ, Kang H, Jordan LC, Donahue MJ. Presurgical Magnetic Resonance Imaging Indicators of Revascularization Response in Adults With Moyamoya Vasculopathy. J Magn Reson Imaging 2022; 56:983-994. [PMID: 35289460 PMCID: PMC9481650 DOI: 10.1002/jmri.28156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 02/13/2022] [Accepted: 03/02/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Moyamoya is a progressive intracranial vasculopathy, primarily affecting distal segments of the internal carotid and middle cerebral arteries. Treatment may comprise angiogenesis-inducing surgical revascularization; however, lack of randomized trials often results in subjective treatment decisions. HYPOTHESIS Compensatory presurgical posterior vertebrobasilar artery (VBA) flow-territory reactivity, including greater cerebrovascular reactivity (CVR) and reduced vascular delay time, portends greater neoangiogenic response verified on digital subtraction angiography (DSA) at 1-year follow-up. STUDY TYPE Prospective intervention cohort. SUBJECTS Thirty-one patients with moyamoya (26 females; age = 45 ± 13 years; 41 revascularized hemispheres). METHODS Anatomical MRI, hypercapnic CVR MRI, and DSA acquired presurgically in adult moyamoya participants scheduled for clinically indicated surgical revascularization. One-year postsurgery, DSA was repeated to evaluate collateralization. FIELD STRENGTH 3 T. SEQUENCE Hypercapnic T 2 * -weighted gradient-echo blood-oxygenation-level-dependent, T2 -weighted turbo-spin-echo fluid-attenuated-inversion-recovery, T1 -weighted magnetization-prepared-rapid-gradient-echo, and T2 -weighted diffusion-weighted-imaging. ASSESSMENT Presurgical maximum CVR and response times were evaluated in VBA flow-territories. Revascularization success was determined using an ordinal scoring system of neoangiogenic collateralization from postsurgical DSA by two cerebrovascular neurosurgeons (R.V.C. with 8 years of experience; M.R.F. with 9 years of experience) and one neuroradiologist (L.T.D. with 8 years of experience). Stroke risk factors (age, sex, race, vasculopathy, and diabetes) were recorded. STATISTICAL TESTS Fisher's exact and Wilcoxon rank-sum tests were applied to compare presurgical variables between cohorts with angiographically confirmed good (>1/3 middle cerebral artery [MCA] territory revascularized) vs. poor (<1/3 MCA territory revascularized) outcomes. SIGNIFICANCE two-sided P < 0.05. Normalized odds ratios (ORs) were calculated. RESULTS Criteria for good collateralization were met in 25 of the 41 revascularized hemispheres. Presurgical normalized VBA flow-territory CVR was significantly higher in those with good (1.12 ± 0.13 unitless) vs. poor (1.04 ± 0.05 unitless) outcomes. Younger (OR = -0.60 ± 0.67) and White (OR = -1.81 ± 1.40) participants had highest revascularization success (good outcomes: age = 42 ± 14 years, race = 84% White; poor outcomes: age = 49 ± 11 years, race = 44% White). DATA CONCLUSION Presurgical MRI-measures of VBA flow-territory CVR are highest in moyamoya participants with better angiographic responses to surgical revascularization. LEVEL OF EVIDENCE 1 TECHNICAL EFFICACY STAGE: 4.
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Affiliation(s)
- Spencer Waddle
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Maria Garza
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Larry T. Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rohan Chitale
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Matthew Fusco
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea Lee
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J. Patel
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lori C. Jordan
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J. Donahue
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
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12
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Deckers PT, Bhogal AA, Dijsselhof MB, Faraco CC, Liu P, Lu H, Donahue MJ, Siero JC. Hemodynamic and metabolic changes during hypercapnia with normoxia and hyperoxia using pCASL and TRUST MRI in healthy adults. J Cereb Blood Flow Metab 2022; 42:861-875. [PMID: 34851757 PMCID: PMC9014679 DOI: 10.1177/0271678x211064572] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Blood oxygenation level-dependent (BOLD) or arterial spin labeling (ASL) MRI with hypercapnic stimuli allow for measuring cerebrovascular reactivity (CVR). Hypercapnic stimuli are also employed in calibrated BOLD functional MRI for quantifying neuronally-evoked changes in cerebral oxygen metabolism (CMRO2). It is often assumed that hypercapnic stimuli (with or without hyperoxia) are iso-metabolic; increasing arterial CO2 or O2 does not affect CMRO2. We evaluated the null hypothesis that two common hypercapnic stimuli, 'CO2 in air' and carbogen, are iso-metabolic. TRUST and ASL MRI were used to measure the cerebral venous oxygenation and cerebral blood flow (CBF), from which the oxygen extraction fraction (OEF) and CMRO2 were calculated for room-air, 'CO2 in air' and carbogen. As expected, CBF significantly increased (9.9% ± 9.3% and 12.1% ± 8.8% for 'CO2 in air' and carbogen, respectively). CMRO2 decreased for 'CO2 in air' (-13.4% ± 13.0%, p < 0.01) compared to room-air, while the CMRO2 during carbogen did not significantly change. Our findings indicate that 'CO2 in air' is not iso-metabolic, while carbogen appears to elicit a mixed effect; the CMRO2 reduction during hypercapnia is mitigated when including hyperoxia. These findings can be important for interpreting measurements using hypercapnic or hypercapnic-hyperoxic (carbogen) stimuli.
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Affiliation(s)
- Pieter T Deckers
- Department of Neurosurgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Alex A Bhogal
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands
| | - Mathijs Bj Dijsselhof
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands.,Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Amsterdam UMC (location VUmc), Amsterdam, Netherlands
| | - Carlos C Faraco
- Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Manus J Donahue
- Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jeroen Cw Siero
- Department of Radiology, Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands.,Spinoza Centre for Neuroimaging, Amsterdam, Netherlands
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13
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Juttukonda MR, Davis LT, Lants SK, Waddle SL, Lee CA, Patel NJ, Jordan LC, Donahue MJ. A Prospective, Longitudinal Magnetic Resonance Imaging Evaluation of Cerebrovascular Reactivity and Infarct Development in Patients With Intracranial Stenosis. J Magn Reson Imaging 2021; 54:912-922. [PMID: 33763922 PMCID: PMC8675276 DOI: 10.1002/jmri.27605] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Patients with symptomatic atherosclerotic and non-atherosclerotic (i.e., moyamoya) intracranial steno-occlusive disease experience high 2-year infarct rates. PURPOSE To investigate whether cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) measures may provide biomarkers of 1-to-2-year infarct risk. STUDY TYPE Prospective, longitudinal study. SUBJECTS Adult participants (age = 18-85 years) with symptomatic intracranial atherosclerotic disease (N = 26) or non-atherosclerotic (i.e., moyamoya; N = 43) and stenosis ≥50% of a major intracranial artery were initially scanned within 45 days of stroke. Follow-up imaging (target = 1.5 years) was acquired for new infarct assessment. FIELD STRENGTH/SEQUENCE 3.0 Tesla with normocapnic arterial spin labeling (ASL) and blood oxygenation level-dependent (BOLD) imaging acquired during an interleaved hypercapnic (3 minutes) and normocapnic (3 minutes) respiratory stimulus. ASSESSMENT CBF, maximum CVR, and time-to-maximum CVR (i.e., CVRDELAY ) were calculated. Laterality indices (difference between infarcted and contralesional hemispheres divided by sum of absolute values) of metrics at enrollment were contrasted between participants with vs. without new infarcts on follow-up. STATISTICAL TESTS Laterality indices were compared using non-parametric Wilcoxon tests (significance: two-sided P < 0.05) and effect sizes as Cohen's d. Continuous variables are presented as mean ± SD. RESULTS New infarcts were observed on follow-up in 15.0% of participants. The laterality index of the CVRDELAY was elevated (P = 0.01) in participants with atherosclerosis with new infarcts (index = 0.13) compared to participants without new infarcts (index = 0.05). DATA CONCLUSION Elevated CVRDELAY may indicate brain parenchyma at increased risk for new infarcts in patients with symptomatic intracranial atherosclerotic disease treated with standard-of-care medical management. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 3.
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Affiliation(s)
- Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital (Charlestown, MA, USA),Radiology, Harvard Medical School (Boston, MA, USA),Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Larry T. Davis
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Sarah K. Lants
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Spencer L. Waddle
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Chelsea A. Lee
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Niral J. Patel
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Lori C. Jordan
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA),Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center (Nashville, TN, USA),Neurology, Vanderbilt University Medical Center (Nashville, TN, USA)
| | - Manus J. Donahue
- Radiology and Radiological Sciences, Vanderbilt University Medical Center (Nashville, TN, USA),Neurology, Vanderbilt University Medical Center (Nashville, TN, USA),Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center (Nashville, TN, USA)
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14
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Impaired cerebrovascular reactivity is associated with recurrent stroke in patients with severe intracranial arterial stenosis: A C02 BOLD fMRI study. J Neuroradiol 2021; 48:339-345. [DOI: 10.1016/j.neurad.2020.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/08/2020] [Accepted: 04/28/2020] [Indexed: 11/20/2022]
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15
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Sleight E, Stringer MS, Marshall I, Wardlaw JM, Thrippleton MJ. Cerebrovascular Reactivity Measurement Using Magnetic Resonance Imaging: A Systematic Review. Front Physiol 2021; 12:643468. [PMID: 33716793 PMCID: PMC7947694 DOI: 10.3389/fphys.2021.643468] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 12/27/2022] Open
Abstract
Cerebrovascular reactivity (CVR) magnetic resonance imaging (MRI) probes cerebral haemodynamic changes in response to a vasodilatory stimulus. CVR closely relates to the health of the vasculature and is therefore a key parameter for studying cerebrovascular diseases such as stroke, small vessel disease and dementias. MRI allows in vivo measurement of CVR but several different methods have been presented in the literature, differing in pulse sequence, hardware requirements, stimulus and image processing technique. We systematically reviewed publications measuring CVR using MRI up to June 2020, identifying 235 relevant papers. We summarised the acquisition methods, experimental parameters, hardware and CVR quantification approaches used, clinical populations investigated, and corresponding summary CVR measures. CVR was investigated in many pathologies such as steno-occlusive diseases, dementia and small vessel disease and is generally lower in patients than in healthy controls. Blood oxygen level dependent (BOLD) acquisitions with fixed inspired CO2 gas or end-tidal CO2 forcing stimulus are the most commonly used methods. General linear modelling of the MRI signal with end-tidal CO2 as the regressor is the most frequently used method to compute CVR. Our survey of CVR measurement approaches and applications will help researchers to identify good practice and provide objective information to inform the development of future consensus recommendations.
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Affiliation(s)
- Emilie Sleight
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael S. Stringer
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom,*Correspondence: Michael S. Stringer
| | - Ian Marshall
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Joanna M. Wardlaw
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael J. Thrippleton
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
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16
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Kaczmarz S, Göttler J, Petr J, Hansen MB, Mouridsen K, Zimmer C, Hyder F, Preibisch C. Hemodynamic impairments within individual watershed areas in asymptomatic carotid artery stenosis by multimodal MRI. J Cereb Blood Flow Metab 2021; 41:380-396. [PMID: 32237952 PMCID: PMC7812517 DOI: 10.1177/0271678x20912364] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Improved understanding of complex hemodynamic impairments in asymptomatic internal carotid artery stenosis (ICAS) is crucial to better assess stroke risks. Multimodal MRI is ideal for measuring brain hemodynamics and has the potential to improve diagnostics and treatment selections. We applied MRI-based perfusion and oxygenation-sensitive imaging in ICAS with the hypothesis that the sensitivity to hemodynamic impairments will improve within individual watershed areas (iWSA). We studied cerebral blood flow (CBF), cerebrovascular reactivity (CVR), relative cerebral blood volume (rCBV), relative oxygen extraction fraction (rOEF), oxygen extraction capacity (OEC) and capillary transit-time heterogeneity (CTH) in 29 patients with asymptomatic, unilateral ICAS (age 70.3 ± 7.0 y) and 30 age-matched healthy controls. In ICAS, we found significant impairments of CBF, CVR, rCBV, OEC, and CTH (strongest lateralization ΔCVR = -24%), but not of rOEF. Although the spatial overlap of compromised hemodynamic parameters within each patient varied in a complex manner, most pronounced changes of CBF, CVR and rCBV were detected within iWSAs (strongest effect ΔCVR = +117%). At the same time, CTH impairments were iWSA independent, indicating widespread dysfunction of capillary-level oxygen diffusivity. In summary, complementary MRI-based perfusion and oxygenation parameters offer deeper perspectives on complex microvascular impairments in individual patients. Furthermore, knowledge about iWSAs improves the sensitivity to hemodynamic impairments.
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Affiliation(s)
- Stephan Kaczmarz
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,MRRC, Yale University, New Haven, CT, USA
| | - Jens Göttler
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,MRRC, Yale University, New Haven, CT, USA.,Department of Radiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | - Jan Petr
- PET Center, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Mikkel Bo Hansen
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Kim Mouridsen
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Claus Zimmer
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | | | - Christine Preibisch
- Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany.,TUM Neuroimaging Center (TUM-NIC), Technical University of Munich (TUM), Munich, Germany.,Clinic for Neurology, School of Medicine, Technical University of Munich (TUM), Munich, Germany
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17
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Milej D, Shahid M, Abdalmalak A, Rajaram A, Diop M, St. Lawrence K. Characterizing dynamic cerebral vascular reactivity using a hybrid system combining time-resolved near-infrared and diffuse correlation spectroscopy. BIOMEDICAL OPTICS EXPRESS 2020; 11:4571-4585. [PMID: 32923065 PMCID: PMC7449704 DOI: 10.1364/boe.392113] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/28/2020] [Accepted: 05/12/2020] [Indexed: 05/09/2023]
Abstract
This study presents the characterization of dynamic cerebrovascular reactivity (CVR) in healthy adults by a hybrid optical system combining time-resolved (TR) near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS). Blood flow and oxygenation (oxy- and deoxy-hemoglobin) responses to a step hypercapnic challenge were recorded to characterize dynamic and static components of CVR. Data were acquired at short and long source-detector separations (r SD) to assess the impact of scalp hemodynamics, and moment analysis applied to the TR-NIRS to further enhance the sensitivity to the brain. Comparing blood flow and oxygenation responses acquired at short and long r SD demonstrated that scalp contamination distorted the CVR time courses, particularly for oxyhemoglobin. This effect was significantly diminished by the greater depth sensitivity of TR NIRS and less evident in the DCS data due to the higher blood flow in the brain compared to the scalp. The reactivity speed was similar for blood flow and oxygenation in the healthy brain. Given the ease-of-use, portability, and non-invasiveness of this hybrid approach, it is well suited to investigate if the temporal relationship between CBF and oxygenation is altered by factors such as age and cerebrovascular disease.
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Affiliation(s)
- Daniel Milej
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Marwan Shahid
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Androu Abdalmalak
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Ajay Rajaram
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Mamadou Diop
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Keith St. Lawrence
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
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18
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Liu P, Xu C, Lin Z, Sur S, Li Y, Yasar S, Rosenberg P, Albert M, Lu H. Cerebrovascular reactivity mapping using intermittent breath modulation. Neuroimage 2020; 215:116787. [PMID: 32278094 DOI: 10.1016/j.neuroimage.2020.116787] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 03/24/2020] [Accepted: 03/30/2020] [Indexed: 01/28/2023] Open
Abstract
Cerebrovascular reactivity (CVR), an index of brain vessel's dilatory capacity, is typically measured using hypercapnic gas inhalation or breath-holding as a vasoactive challenge. However, these methods require considerable subject cooperation and could be challenging in clinical studies. More recently, there have been attempts to use resting-state BOLD data to map CVR by utilizing spontaneous changes in breathing pattern. However, in subjects who have small fluctuations in their spontaneous breathing pattern, the CVR results could be noisy and unreliable. In this study, we aim to develop a new method for CVR mapping that does not require gas-inhalation yet provides substantially higher sensitivity than resting-state CVR mapping. This new method is largely based on resting-state scan, but introduces intermittent modulation of breathing pattern in the subject to enhance fluctuations in their end-tidal CO2 (EtCO2) level. Here we examined the comfort level, sensitivity, and accuracy of this method in two studies. First, in 8 healthy young subjects, we developed the intermittent breath-modulation method using two different modulation frequencies, 6 s per breath and 12 s per breath, respectively, and compared the results to three existing CVR methods, specifically hypercapnic gas inhalation, breath-holding, and resting-state. Our results showed that the comfort level of the 6-s breath-modulation method was significantly higher than breath-holding (p = 0.007) and CO2-inhalation (p = 0.015) methods, while not different from the resting-state, i.e. free breathing method (p = 0.52). When comparing the sensitivity of CVR methods, the breath-modulation methods revealed higher Z-statistics compared to the resting-state scan (p < 0.008) and was comparable to breath-holding results. Next, we tested the feasibility of breath-modulation CVR mapping (6 s per breath) in 21 cognitively normal elderly participants and compared quantitative CVR values to that obtained with the CO2-inhalation method. Whole-brain CVR was found to be 0.150 ± 0.055 and 0.154 ± 0.032 %ΔBOLD/mmHg for the breath-modulation and CO2-inhalation method, respectively, with a significant correlation between them (y = 0.97x, p = 0.007). CVR mapping with intermittent breath modulation may be a useful method that combines the advantages of resting-state and CO2-inhalation based approaches.
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Affiliation(s)
- Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Cuimei Xu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zixuan Lin
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sandeepa Sur
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yang Li
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sevil Yasar
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Paul Rosenberg
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
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19
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Lin MP, Brott TG, Liebeskind DS, Meschia JF, Sam K, Gottesman RF. Collateral Recruitment Is Impaired by Cerebral Small Vessel Disease. Stroke 2020; 51:1404-1410. [PMID: 32248770 DOI: 10.1161/strokeaha.119.027661] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- Cerebral small vessel disease (SVD) is associated with increased stroke risk and poor stroke outcomes. We aimed to evaluate whether chronic SVD burden is associated with poor recruitment of collaterals in large-vessel occlusive stroke. Methods- Consecutive patients with middle cerebral artery or internal carotid artery occlusion presenting within 6 hours after stroke symptom onset who underwent thrombectomy from 2012 to 2017 were included. The prespecified primary outcome was poor collateral flow, which was assessed on baseline computed tomographic angiography (poor, ≤50% filling; good, >50% filling). Markers of chronic SVD on brain magnetic resonance imaging were rated for the extent of white matter hyperintensities, enlarged perivascular spaces, chronic lacunar infarctions and cerebral microbleeds using the Standards for Reporting Vascular Changes on Neuroimaging criteria. Severity of SVD was quantified by adding the presence of each SVD feature, with a total possible score of 0 to 4; each SVD type was also evaluated separately. Multivariable logistic regression analyses were performed to evaluate the relationships between SVD and poor collaterals, with adjustment for potential confounders. Results- Of the 100 eligible patients, the mean age was 65±16 years, median National Institutes of Health Stroke Scale score was 15, and 68% had any SVD. Poor collaterals were observed in 46%, and those with SVD were more likely to have poor collaterals than patients without SVD (aOR, 1.9 [95% CI, 1.1-3.2]). Of the SVD types, poor collaterals were significantly associated with white matter hyperintensities (aOR, 2.9 per Fazekas increment [95% CI, 1.6-5.3]) but not with enlarged perivascular spaces (adjusted odds ratio [aOR], 1.3 [95% CI, 0.4-4.0]), lacunae (aOR, 2.1 [95% CI, 0.6-7.1]), or cerebral microbleeds (aOR, 2.1 [95% CI, 0.6-7.8]). Having a greater number of different SVD markers was associated with a higher odds of poor collaterals (crude trend P<0.001; adjusted P=0.056). There was a dose-dependent relationship between white matter hyperintensity burden and poor collaterals: adjusted odds of poor collaterals were 1.5, 3.0, and 9.7 across Fazekas scores of 1 to 3 (Ptrend=0.015). No patient with an SVD score of 4 had good collaterals. Conclusions- Chronic cerebral SVD is associated with poor recruitment of collaterals in large vessel occlusive stroke. A prospective study to elucidate the potential mechanism of how SVD may impair the recruitment of collaterals is ongoing.
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Affiliation(s)
- Michelle P Lin
- From the Department of Neurology, Mayo Clinic, Jacksonville, FL (M.P.L., T.G.B., J.F.M.)
| | - Thomas G Brott
- From the Department of Neurology, Mayo Clinic, Jacksonville, FL (M.P.L., T.G.B., J.F.M.)
| | - David S Liebeskind
- Department of Neurology, University of California in Los Angeles (D.S.L.)
| | - James F Meschia
- From the Department of Neurology, Mayo Clinic, Jacksonville, FL (M.P.L., T.G.B., J.F.M.)
| | - Kevin Sam
- Department of Radiology (K.S.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Rebecca F Gottesman
- Department of Neurology (R.F.G.), Johns Hopkins University School of Medicine, Baltimore, MD
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20
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Waddle SL, Juttukonda MR, Lants SK, Davis LT, Chitale R, Fusco MR, Jordan LC, Donahue MJ. Classifying intracranial stenosis disease severity from functional MRI data using machine learning. J Cereb Blood Flow Metab 2020; 40:705-719. [PMID: 31068081 PMCID: PMC7168799 DOI: 10.1177/0271678x19848098] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Translation of many non-invasive hemodynamic MRI methods to cerebrovascular disease patients has been hampered by well-known artifacts associated with delayed blood arrival times and reduced microvascular compliance. Using machine learning and support vector machine (SVM) algorithms, we investigated whether arrival time-related artifacts in these methods could be exploited as novel contrast sources to discriminate angiographically confirmed stenotic flow territories. Intracranial steno-occlusive moyamoya patients (n = 53; age = 45 ± 14.2 years; sex = 43 F) underwent (i) catheter angiography, (ii) anatomical MRI, (iii) cerebral blood flow (CBF)-weighted arterial spin labeling, and (iv) cerebrovascular reactivity (CVR)-weighted hypercapnic blood-oxygenation-level-dependent MRI. Mean, standard deviation (std), and 99th percentile of CBF, CVR, CVRDelay, and CVRMax were calculated in major anterior and posterior flow territories perfused by vessels with vs. without stenosis (≥70%) confirmed by catheter angiography. These and demographic variables were input into SVMs to evaluate discriminatory capacity for stenotic flow territories using k-fold cross-validation and receiver-operating-characteristic-area-under-the-curve to quantify variable combination relevance. Anterior circulation CBF-std, attributable to heterogeneous endovascular signal and prolonged arterial transit times, was the best performing single variable and CVRDelay-mean and CBF-std, both reflective of delayed vascular compliance, were a high-performing two-variable combination (specificity = 0.67; sensitivity = 0.75). Findings highlight the relevance of hemodynamic imaging and machine learning for identifying cerebrovascular impairment.
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Affiliation(s)
- Spencer L Waddle
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sarah K Lants
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Larry T Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rohan Chitale
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Matthew R Fusco
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
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21
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Watchmaker JM, Frederick BD, Fusco MR, Davis LT, Juttukonda MR, Lants SK, Kirshner HS, Donahue MJ. Clinical Use of Cerebrovascular Compliance Imaging to Evaluate Revascularization in Patients With Moyamoya. Neurosurgery 2020. [PMID: 29528447 DOI: 10.1093/neuros/nyx635] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Surgical revascularization is often performed in patients with moyamoya, however routine tools for efficacy evaluation are underdeveloped. The gold standard is digital subtraction angiography (DSA); however, DSA requires ionizing radiation and procedural risk, and therefore is suboptimal for routine surveillance of parenchymal health. OBJECTIVE To determine whether parenchymal vascular compliance measures, obtained noninvasively using magnetic resonance imaging (MRI), provide surrogates to revascularization success by comparing measures with DSA before and after surgical revascularization. METHODS Twenty surgical hemispheres with DSA and MRI performed before and after revascularization were evaluated. Cerebrovascular reactivity (CVR)-weighted images were acquired using hypercapnic 3-Tesla gradient echo blood oxygenation level-dependent MRI. Standard and novel analysis algorithms were applied (i) to quantify relative CVR (rCVRRAW), and decompose this response into (ii) relative maximum CVR (rCVRMAX) and (iii) a surrogate measure of the time for parenchyma to respond maximally to the stimulus, CVRDELAY. Measures between time points in patients with good and poor surgical outcomes based on DSA-visualized neoangiogenesis were contrasted (signed-rank test; significance: 2-sided P < .050). RESULTS rCVRRAW increases (P = .010) and CVRDELAY decreases (P = .001) were observed pre- vs post-revascularization in hemispheres with DSA-confirmed collateral formation; no difference was found pre- vs post-revascularization in hemispheres with poor revascularization. No significant change in rCVRMAX post-revascularization was observed in either group, or between any of the MRI measures, in the nonsurgical hemisphere. CONCLUSION Improvement in parenchymal compliance measures post-revascularization, primarily attributed to reductions in microvascular response time, is concurrent with collateral formation visualized on DSA, and may be useful for longitudinal monitoring of surgical outcomes.
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Affiliation(s)
- Jennifer M Watchmaker
- Vanderbilt University of Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Blaise deB Frederick
- Brain Imaging Center, McLean Hospital, Belmont, Massachusetts.,Consolidated Department of Psychiatry, Harvard Medical School, Boston Massachusetts
| | - Matthew R Fusco
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Larry T Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Meher R Juttukonda
- Vanderbilt University of Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Sarah K Lants
- Vanderbilt University of Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Howard S Kirshner
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Manus J Donahue
- Vanderbilt University of Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Psychiatry, Vanderbilt University Medical Center, Nashville, Tennessee
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22
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Arteaga DF, Strother MK, Faraco CC, Davis LT, Scott AO, Donahue MJ. Cerebral blood flow territory instability in patients with atherosclerotic intracranial stenosis. J Magn Reson Imaging 2019; 50:1441-1451. [PMID: 30938468 PMCID: PMC6774918 DOI: 10.1002/jmri.26737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 03/15/2019] [Accepted: 03/18/2019] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Stroke risk stratification in patients with symptomatic intracranial atherosclerotic arterial disease (ICAD) remains an important clinical objective owing to the high 14-19% recurrent stroke rate in these patients on standard-of-care medical management. There thus remains a need for hemodynamic markers that may allow for the selection of personalized therapies for high-risk symptomatic patients. PURPOSE To determine if shifting of cerebral blood flow (CBF) territories in response to changes in cerebral perfusion pressure (CPP) may provide a marker for stroke risk in ICAD patients. STUDY TYPE Prospective. POPULATION Twenty ICAD patients who experienced a stroke within 45 days of study enrollment and 10 healthy controls. SEQUENCE 3.0T MRI including anatomical imaging (T1 -weighted, T2 -weighted/FLAIR), 3D MR angiography, and normocapnic and hypercapnic vessel-encoded CBF-weighted arterial spin labeling. ASSESSMENT Patients were scanned within 45 days of overt stroke and monitored (duration = 13.2 ± 4.4 months) for the endpoint of non-cardioembolic stroke or transient ischemic attack. Flow territory shifting (shifting index) was calculated from the first scan by determining whether a voxel shifted from its primary arterial source from normocapnia to hypercapnia. STATISTICAL TESTS A Mann-Whitney U-test (significance: P < 0.05) was performed to determine whether patients meeting the endpoint had greater shifting indices relative to controls or patients not meeting the endpoint. RESULTS Shifting indices (mean ± standard error) were significantly higher in patients meeting endpoint criteria relative to controls (P = 0.0057; adjusted P = 0.036) and patients not meeting endpoint criteria (P = 0.0047; adjusted P = 0.036). DATA CONCLUSION Flow territory shifting may provide a marker of recurrent stroke risk in symptomatic ICAD patients on standard-of-care medical management therapies. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1441-1451.
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Affiliation(s)
- Daniel F. Arteaga
- Dept. of Neurology, University of Virginia, Charlottesville, VA
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
| | - Megan K. Strother
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
| | - Carlos C. Faraco
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
| | - L. Taylor Davis
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
| | - Allison O. Scott
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
| | - Manus J. Donahue
- Dept. of Radiology, Vanderbilt University Medical Center, Nashville, TN
- Dept. of Neurology, Vanderbilt University Medical Center, Nashville, TN
- Dept. of Psychiatry, Vanderbilt University Medical Center, Nashville, TN
- Dept. of Physics and Astronomy, Vanderbilt University, Nashville, TN
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23
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Tong Y, Hocke LM, Frederick BB. Low Frequency Systemic Hemodynamic "Noise" in Resting State BOLD fMRI: Characteristics, Causes, Implications, Mitigation Strategies, and Applications. Front Neurosci 2019; 13:787. [PMID: 31474815 PMCID: PMC6702789 DOI: 10.3389/fnins.2019.00787] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 07/15/2019] [Indexed: 01/06/2023] Open
Abstract
Advances in functional magnetic resonance imaging (fMRI) acquisition have improved signal to noise to the point where the physiology of the subject is the dominant noise source in resting state fMRI data (rsfMRI). Among these systemic, non-neuronal physiological signals, respiration and to some degree cardiac fluctuations can be removed through modeling, or in the case of newer, faster acquisitions such as simultaneous multislice acquisition, simple spectral filtering. However, significant low frequency physiological oscillation (∼0.01-0.15 Hz) remains in the signal. This is problematic, as it is the precise frequency band occupied by the neuronally modulated hemodynamic responses used to study brain connectivity, precluding its removal by spectral filtering. The source of this signal, and its method of production and propagation in the body, have not been conclusively determined. Here, we summarize the defining characteristics of the systemic low frequency noise signal, and review some current theories about the signal source and the evidence supporting them. The strength and distribution of the systemic LFO signal make characterizing and removing it essential for accurate quantification, especially for resting state connectivity, when no stimulation can be compared with the signal. Widespread correlated non-neuronal signals obscure and distort the more localized patterns of neuronal correlations between interacting brain regions; they may even cause apparent connectivity between regions with no neuronal interaction. Here, we discuss a simple method we have developed to parse the global, moving, blood-borne signal from the stationary, neuronal connectivity signals, substantially reducing the negative correlations that result from global signal regression. Finally, we will discuss some of the uses to which the moving systemic low frequency oscillation can be put if we consider it a "signal" carrying information, rather than simply "noise" complicating the interpretation of resting state connectivity. Properly utilizing this signal may offer insights into subtle hemodynamic alterations that can be used as early indicators of circulatory dysfunction in a number of neuropsychiatric conditions, such as prodromal stroke, moyamoya, and Alzheimer's disease.
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Affiliation(s)
- Yunjie Tong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States
| | - Lia M. Hocke
- McLean Imaging Center, McLean Hospital, Belmont, MA, United States
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States
| | - Blaise B. Frederick
- McLean Imaging Center, McLean Hospital, Belmont, MA, United States
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States
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24
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McKetton L, Cohn M, Tang-Wai DF, Sobczyk O, Duffin J, Holmes KR, Poublanc J, Sam K, Crawley AP, Venkatraghavan L, Fisher JA, Mikulis DJ. Cerebrovascular Resistance in Healthy Aging and Mild Cognitive Impairment. Front Aging Neurosci 2019; 11:79. [PMID: 31031616 PMCID: PMC6474328 DOI: 10.3389/fnagi.2019.00079] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 03/19/2019] [Indexed: 12/04/2022] Open
Abstract
Measures of cerebrovascular reactivity (CVR) are used to judge the health of the brain vasculature. In this study, we report the use of several different analyses of blood oxygen dependent (BOLD) fMRI responses to CO2 to provide a number of metrics of CVR based on the sigmoidal resistance response to CO2. To assess possible differences in these metrics with age, we compiled atlases reflecting voxel-wise means and standard deviations for four different age ranges and for a group of patients with mild cognitive impairment (MCI) and compared them. Sixty-seven subjects were recruited for this study and scanned at 3T field strength. Of those, 51 healthy control volunteers between the ages of 18–83 were recruited, and 16 (MCI) subjects between the ages of 61–83 were recruited. Testing was carried out using an automated computer-controlled gas blender to induce hypercapnia in a step and ramp paradigm while monitoring end-tidal partial pressures of CO2. Surprisingly, some resistance sigmoid parameters in the oldest control group were increased compared to the youngest control group. Resistance amplitude maps showed increases in clusters within the temporal cortex, thalamus, corpus callosum and brainstem, and resistance reserve maps showed increases in clusters within the cingulate cortex, frontal gyrus, and corpus callosum. These findings suggest that some aspects of vascular reactivity in parts of the brain are initially maintained with age but then may increase in later years. We found significant reductions in all resistance sigmoid parameters (amplitude, reserve, sensitivity, midpoint, and range) when comparing MCI patients to controls. Additionally, in controls and in MCI patients, amplitude, range, reserve, and sensitivity in white matter (WM) was significantly reduced compared to gray matter (GM). WM midpoints were significantly above those of GM. Our general conclusion is that vascular regulation in terms of cerebral blood flow (CBF) responsiveness to CO2 is not significantly affected by age, but is reduced in MCI. These changes in cerebrovascular regulation demonstrate the value of resistance metrics for mapping areas of dysregulated blood flow in individuals with MCI. They may also be of value in the investigation of patients with vascular risk factors at risk for developing vascular dementia.
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Affiliation(s)
- Larissa McKetton
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Melanie Cohn
- Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Department of Psychology, University of Toronto, Toronto, ON, Canada
| | - David F Tang-Wai
- Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Department of Medicine, Division of Neurology, University of Toronto and the University Health Network Memory Clinic, Toronto, ON, Canada
| | - Olivia Sobczyk
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - James Duffin
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Kenneth R Holmes
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Julien Poublanc
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Kevin Sam
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Adrian P Crawley
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada
| | - Lashmi Venkatraghavan
- Department of Anaesthesia and Pain Management, University Health Network (UHN), Toronto, ON, Canada
| | - Joseph A Fisher
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Department of Anaesthesia and Pain Management, University Health Network (UHN), Toronto, ON, Canada
| | - David J Mikulis
- Joint Department of Medical Imaging, University Health Network (UHN), Toronto, ON, Canada.,Krembil Brain Institute, University Health Network (UHN), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
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25
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Cohen AD, Wang Y. Improving the Assessment of Breath-Holding Induced Cerebral Vascular Reactivity Using a Multiband Multi-echo ASL/BOLD Sequence. Sci Rep 2019; 9:5079. [PMID: 30911056 PMCID: PMC6434035 DOI: 10.1038/s41598-019-41199-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 02/28/2019] [Indexed: 01/18/2023] Open
Abstract
Breath holding (BH) is a viable vasodilatory stimulus for calculating functional MRI-derived cerebral vascular reactivity (CVR). The BH technique suffers from reduced repeatability compared with gas inhalation techniques; however, extra equipment is needed to perform gas inhalation techniques, and this equipment is not available at all institutions. This study aimed to determine the sensitivity and repeatability of BH activation and CVR using a multiband multi-echo simultaneous arterial spin labelling/blood oxygenation level dependent (ASL/BOLD) sequence. Whole-brain images were acquired in 14 volunteers. Ten subjects returned for repeat imaging. Each subject performed four cycles of 16 s BH on expiration interleaved with paced breathing. Following standard preprocessing, the echoes were combined using a T2*-weighted approach. BOLD and ASL BH activation was computed, and CVR was then determined as the percent signal change related to the activation. The "M" parameter from the Davis Model was also computed by incorporating the ASL signal. Our results showed higher BH activation strength, volume, and repeatability for the combined multi-echo (MEC) data compared with the single-echo data. MEC CVR also had higher repeatability, sensitivity, specificity, and reliability compared with the single-echo BOLD data. These data support the usefulness of an MBME ASL/BOLD acquisition for BH CVR and M measurements.
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Affiliation(s)
- Alexander D Cohen
- Medical College of Wisconsin, Department of Radiology, Milwaukee, WI, USA.
| | - Yang Wang
- Medical College of Wisconsin, Department of Radiology, Milwaukee, WI, USA.
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26
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Juttukonda MR, Donahue MJ. Neuroimaging of vascular reserve in patients with cerebrovascular diseases. Neuroimage 2019; 187:192-208. [PMID: 29031532 PMCID: PMC5897191 DOI: 10.1016/j.neuroimage.2017.10.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 10/01/2017] [Accepted: 10/07/2017] [Indexed: 12/21/2022] Open
Abstract
Cerebrovascular reactivity, defined broadly as the ability of brain parenchyma to adjust cerebral blood flow in response to altered metabolic demand or a vasoactive stimulus, is being measured with increasing frequency and may have a use for portending new or recurrent stroke risk in patients with cerebrovascular disease. The purpose of this review is to outline (i) the physiological basis of variations in cerebrovascular reactivity, (ii) available approaches for measuring cerebrovascular reactivity in research and clinical settings, and (iii) clinically-relevant cerebrovascular reactivity findings in the context of patients with cerebrovascular disease, including atherosclerotic arterial steno-occlusion, non-atherosclerotic arterial steno-occlusion, anemia, and aging. Literature references summarizing safety considerations for these procedures and future directions for standardizing protocols and post-processing procedures across centers are presented in the specific context of major unmet needs in the setting of cerebrovascular disease.
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Affiliation(s)
- Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA.
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27
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Hua J, Liu P, Kim T, Donahue M, Rane S, Chen JJ, Qin Q, Kim SG. MRI techniques to measure arterial and venous cerebral blood volume. Neuroimage 2019; 187:17-31. [PMID: 29458187 PMCID: PMC6095829 DOI: 10.1016/j.neuroimage.2018.02.027] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 12/14/2022] Open
Abstract
The measurement of cerebral blood volume (CBV) has been the topic of numerous neuroimaging studies. To date, however, most in vivo imaging approaches can only measure CBV summed over all types of blood vessels, including arterial, capillary and venous vessels in the microvasculature (i.e. total CBV or CBVtot). As different types of blood vessels have intrinsically different anatomy, function and physiology, the ability to quantify CBV in different segments of the microvascular tree may furnish information that is not obtainable from CBVtot, and may provide a more sensitive and specific measure for the underlying physiology. This review attempts to summarize major efforts in the development of MRI techniques to measure arterial (CBVa) and venous CBV (CBVv) separately. Advantages and disadvantages of each type of method are discussed. Applications of some of the methods in the investigation of flow-volume coupling in healthy brains, and in the detection of pathophysiological abnormalities in brain diseases such as arterial steno-occlusive disease, brain tumors, schizophrenia, Huntington's disease, Alzheimer's disease, and hypertension are demonstrated. We believe that the continual development of MRI approaches for the measurement of compartment-specific CBV will likely provide essential imaging tools for the advancement and refinement of our knowledge on the exquisite details of the microvasculature in healthy and diseased brains.
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Affiliation(s)
- Jun Hua
- Neurosection, Div. of MRI Research, Dept. of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA.
| | - Peiying Liu
- Neurosection, Div. of MRI Research, Dept. of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Tae Kim
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Manus Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Swati Rane
- Radiology, University of Washington Medical Center, Seattle, WA, USA
| | - J Jean Chen
- Rotman Research Institute, Baycrest Centre, Canada; Department of Medical Biophysics, University of Toronto, Canada
| | - Qin Qin
- Neurosection, Div. of MRI Research, Dept. of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Seong-Gi Kim
- Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, South Korea; Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
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28
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Hauser TK, Seeger A, Bender B, Klose U, Thurow J, Ernemann U, Tatagiba M, Meyer PT, Khan N, Roder C. Hypercapnic BOLD MRI compared to H 215O PET/CT for the hemodynamic evaluation of patients with Moyamoya Disease. NEUROIMAGE-CLINICAL 2019; 22:101713. [PMID: 30743136 PMCID: PMC6370561 DOI: 10.1016/j.nicl.2019.101713] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 01/14/2019] [Accepted: 02/03/2019] [Indexed: 11/30/2022]
Abstract
Background and purpose Patients with Moyamoya Disease (MMD) need hemodynamic evaluation of vascular territories at risk of stroke. Today's investigative standards include H215O PET/CT with pharmacological challenges with acetazolamide (ACZ). Recent developments suggest that CO2-triggered blood‑oxygen-level-dependent (BOLD) functional MRI might provide comparable results to current standard methods for evaluation of territorial hemodynamics, while being a more widely available and easily implementable method. This study examines results of a newly developed quantifiable analysis algorithm for CO2-triggered BOLD MRI in Moyamoya patients and correlates the results with H215O PET/CT with ACZ challenge to assess comparability between both modalities. Methods CO2-triggered BOLD MRI was performed and compared to H215O PET/CT with ACZ challenge in patients with angiographically proven MMD. Images of both modalities were analyzed retrospectively in a blinded, standardized fashion by visual inspection, as well as with a semi-quantitative analysis using stimuli-induced approximated regional perfusion-weighted data and BOLD-signal changes with reference to cerebellum. Results 20 consecutive patients fulfilled the inclusion criteria, a total of 160 vascular territories were analyzed retrospectively. Visual analysis (4-step visual rating system) of standardized, color-coded cerebrovascular reserve/reactivity maps showed a very strong correlation (Spearman's rho = 0.9, P < 0.001) between both modalities. Likewise, comparison of approximated regional perfusion changes across vascular territories (normalized to cerebellar change) reveal a highly significant correlation between both methods (Pearson's r = 0.71, P < 0.001). Conclusions The present analysis indicates that CO2-triggered BOLD MRI is a very promising tool for the hemodynamic evaluation of MMD patients with results comparable to those seen in H215O PET/CT with ACZ challenge. It therefore holds future potential in becoming a routine examination in the pre- and postoperative evaluation of MMD patients after further prospective evaluation. Non-invasive cerebrovascular reactivity measurement with BOLD MRI. CO2-triggered BOLD MRI correlates strongly with H215O PET/CT with ACZ challenge Widely-available tool for the hemodynamic evaluation of Moyamoya patients.
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Affiliation(s)
| | - Achim Seeger
- Department of Neuroradiology, Eberhard Karls University Tübingen, Germany
| | - Benjamin Bender
- Department of Neuroradiology, Eberhard Karls University Tübingen, Germany
| | - Uwe Klose
- Department of Neuroradiology, Eberhard Karls University Tübingen, Germany
| | - Johannes Thurow
- Department of Nuclear Medicine, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ulrike Ernemann
- Department of Neuroradiology, Eberhard Karls University Tübingen, Germany
| | - Marcos Tatagiba
- Department of Neurosurgery, Eberhard Karls University Tübingen, Germany
| | - Philipp T Meyer
- Department of Nuclear Medicine, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Nadia Khan
- Department of Neurosurgery, Eberhard Karls University Tübingen, Germany; Moyamoya Center, Division of Pediatric Neurosurgery, University Children's Hospital Zürich, Switzerland.
| | - Constantin Roder
- Department of Neurosurgery, Eberhard Karls University Tübingen, Germany
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29
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Watchmaker JM, Juttukonda MR, Davis LT, Scott AO, Faraco CC, Gindville MC, Jordan LC, Cogswell PM, Jefferson AL, Kirshner HS, Donahue MJ. Hemodynamic mechanisms underlying elevated oxygen extraction fraction (OEF) in moyamoya and sickle cell anemia patients. J Cereb Blood Flow Metab 2018; 38:1618-1630. [PMID: 28029271 PMCID: PMC6125968 DOI: 10.1177/0271678x16682509] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Moyamoya is a bilateral, complex cerebrovascular condition characterized by progressive non-atherosclerotic intracranial stenosis and collateral vessel formation. Moyamoya treatment focuses on restoring cerebral blood flow (CBF) through surgical revascularization, however stratifying patients for revascularization requires abilities to quantify how well parenchyma is compensating for arterial steno-occlusion. Globally elevated oxygen extraction fraction (OEF) secondary to CBF reduction may serve as a biomarker for tissue health in moyamoya patients, as suggested in patients with sickle cell anemia (SCA) and reduced oxygen carrying capacity. Here, OEF was measured (TRUST-MRI) to test the hypothesis that OEF is globally elevated in patients with moyamoya (n = 18) and SCA (n = 18) relative to age-matched controls (n = 43). Mechanisms underlying the hypothesized OEF increases were evaluated by performing sequential CBF-weighted, cerebrovascular reactivity (CVR)-weighted, and structural MRI. Patients were stratified by treatment and non-parametric tests applied to compare study variables (significance: two-sided P < 0.05). OEF was significantly elevated in moyamoya participants (interquartile range = 0.38-0.45) compared to controls (interquartile range = 0.29-0.38), similar to participants with SCA (interquartile range = 0.37-0.45). CBF was inversely correlated with OEF in moyamoya participants. Elevated OEF was only weakly related to reductions in CVR, consistent with basal CBF level, rather than vascular reserve capacity, being most closely associated with OEF.
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Affiliation(s)
- Jennifer M Watchmaker
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Meher R Juttukonda
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Larry T Davis
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Allison O Scott
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Carlos C Faraco
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Melissa C Gindville
- 2 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, USA
| | - Lori C Jordan
- 2 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, USA
| | - Petrice M Cogswell
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA
| | - Angela L Jefferson
- 3 Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, USA.,4 Department of Neurology, Vanderbilt University Medical Center, Nashville, USA
| | - Howard S Kirshner
- 4 Department of Neurology, Vanderbilt University Medical Center, Nashville, USA
| | - Manus J Donahue
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, USA.,4 Department of Neurology, Vanderbilt University Medical Center, Nashville, USA.,5 Department of Psychiatry, Vanderbilt University Medical Center, Nashville, USA
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30
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Derdeyn CP. Hemodynamics and oxygen extraction in chronic large artery steno-occlusive disease: Clinical applications for predicting stroke risk. J Cereb Blood Flow Metab 2018; 38:1584-1597. [PMID: 28925313 PMCID: PMC6125965 DOI: 10.1177/0271678x17732884] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Depending on the adequacy of collateral sources of blood flow, arterial stenosis or occlusion may lead to reduced perfusion pressure and ultimately reduced blood flow in the distal territory supplied by that vessel. There are two well-defined compensatory mechanisms to reduced pressure or flow - autoregulatory vasodilation and increased oxygen extraction fraction. Other changes, such as metabolic downregulation, are likely. The positive identification of autoregulatory vasodilation and increased oxygen extraction fraction in humans is an established risk factor for future ischemic stroke in some disease states such as atherosclerotic carotid stenosis and occlusion. The mechanisms by which ischemic stroke may occur are not clear, and may include an increased vulnerability to embolic events. The use of hemodynamic assessment to identify patients with occlusive vasculopathy at an increased risk for stroke is very appealing for several different patient populations, such as those with symptomatic intracranial atherosclerotic disease, moyamoya phenomenon, complete internal carotid artery occlusion, and asymptomatic cervical carotid artery stenosis. While there is very good data for stroke risk prediction in some of these groups, no intervention based on these tools has been proven effective yet. In this manuscript, we will review these topics above and identify areas for future research.
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Affiliation(s)
- Colin P Derdeyn
- Departments of Radiology and Neurology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
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31
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Donahue MJ, Achten E, Cogswell PM, De Leeuw FE, Derdeyn CP, Dijkhuizen RM, Fan AP, Ghaznawi R, Heit JJ, Ikram MA, Jezzard P, Jordan LC, Jouvent E, Knutsson L, Leigh R, Liebeskind DS, Lin W, Okell TW, Qureshi AI, Stagg CJ, van Osch MJP, van Zijl PCM, Watchmaker JM, Wintermark M, Wu O, Zaharchuk G, Zhou J, Hendrikse J. Consensus statement on current and emerging methods for the diagnosis and evaluation of cerebrovascular disease. J Cereb Blood Flow Metab 2018; 38:1391-1417. [PMID: 28816594 PMCID: PMC6125970 DOI: 10.1177/0271678x17721830] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 05/26/2017] [Accepted: 06/10/2017] [Indexed: 01/04/2023]
Abstract
Cerebrovascular disease (CVD) remains a leading cause of death and the leading cause of adult disability in most developed countries. This work summarizes state-of-the-art, and possible future, diagnostic and evaluation approaches in multiple stages of CVD, including (i) visualization of sub-clinical disease processes, (ii) acute stroke theranostics, and (iii) characterization of post-stroke recovery mechanisms. Underlying pathophysiology as it relates to large vessel steno-occlusive disease and the impact of this macrovascular disease on tissue-level viability, hemodynamics (cerebral blood flow, cerebral blood volume, and mean transit time), and metabolism (cerebral metabolic rate of oxygen consumption and pH) are also discussed in the context of emerging neuroimaging protocols with sensitivity to these factors. The overall purpose is to highlight advancements in stroke care and diagnostics and to provide a general overview of emerging research topics that have potential for reducing morbidity in multiple areas of CVD.
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Affiliation(s)
- Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
| | - Eric Achten
- Department of Radiology and Nuclear Medicine, Universiteit Gent, Gent, Belgium
| | - Petrice M Cogswell
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Frank-Erik De Leeuw
- Radboud University, Nijmegen Medical Center, Donders Institute Brain Cognition & Behaviour, Center for Neuroscience, Department of Neurology, Nijmegen, The Netherlands
| | - Colin P Derdeyn
- Department of Radiology and Neurology, University of Iowa, Iowa City, IA, USA
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Audrey P Fan
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Rashid Ghaznawi
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeremy J Heit
- Department of Radiology, Neuroimaging and Neurointervention Division, Stanford University, CA, USA
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands
- Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
| | - Peter Jezzard
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eric Jouvent
- Department of Neurology, AP-HP, Lariboisière Hospital, Paris, France
| | - Linda Knutsson
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Richard Leigh
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | | | - Weili Lin
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Thomas W Okell
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Adnan I Qureshi
- Department of Neurology, Zeenat Qureshi Stroke Institute, St. Cloud, MN, USA
| | - Charlotte J Stagg
- Oxford Centre for Human Brain Activity, University of Oxford, Oxford, UK
| | | | - Peter CM van Zijl
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Jennifer M Watchmaker
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Max Wintermark
- Department of Radiology, Neuroimaging and Neurointervention Division, Stanford University, CA, USA
| | - Ona Wu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Greg Zaharchuk
- Department of Radiology, Neuroimaging and Neurointervention Division, Stanford University, CA, USA
| | - Jinyuan Zhou
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
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32
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Jordan LC, DeBaun MR. Cerebral hemodynamic assessment and neuroimaging across the lifespan in sickle cell disease. J Cereb Blood Flow Metab 2018; 38:1438-1448. [PMID: 28417646 PMCID: PMC6125971 DOI: 10.1177/0271678x17701763] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Children and adults with sickle cell anemia (SCA) have a higher risk of strokes compared to age- and race-matched peers. Velocity in the middle cerebral or distal internal carotid artery as measured by transcranial Doppler ultrasound is a recognized method to identify children but not adults with SCA at high-risk for first stroke. For both children and adults with SCA that have had a stroke, no methods clearly identify individuals at highest risk of recurrent strokes or an initial silent stroke, the most common neurological injury. Methods to assess cerebral hemodynamics in SCA have been utilized for decades but often required radiotracers making them not feasible for screening and longitudinal follow-up. MRI approaches that do not require exogenous contrast have been introduced and are appealing in both clinical and research scenarios. Improved neuroimaging strategies hold promise for identifying individuals with SCA at increased risk of initial and recurrent infarcts, justifying more aggressive risk-based therapy. We review the epidemiology of stroke in SCA, the impact of strokes, stroke mechanisms, and potential imaging strategies including regional and global oxygen extraction fraction, cerebral blood flow, and vessel wall imaging to identify individuals at high-risk of stroke.
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Affiliation(s)
- Lori C Jordan
- 1 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Michael R DeBaun
- 2 Department of Pediatrics, Vanderbilt-Meharry Sickle Cell Disease Center of Excellence, Vanderbilt University Medical Center, Nashville, TN, USA
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De Vis JB, Bhogal AA, Hendrikse J, Petersen ET, Siero JCW. Effect sizes of BOLD CVR, resting-state signal fluctuations and time delay measures for the assessment of hemodynamic impairment in carotid occlusion patients. Neuroimage 2018; 179:530-539. [PMID: 29913284 PMCID: PMC6057274 DOI: 10.1016/j.neuroimage.2018.06.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 06/01/2018] [Accepted: 06/05/2018] [Indexed: 11/17/2022] Open
Abstract
Background and purpose The BOLD signal amplitude as a response to a hypercapnia stimulus is commonly used to assess cerebrovascular reserve. Despite recent advances, the implementation remains cumbersome and alternative ways to assess hemodynamic impairment are desirable. Resting-state BOLD signal fluctuations (rsBOLD) have been proposed however data on its sensitivity and dependence on baseline venous cerebral blood volume (vCBV) is limited. The primary aim of this study was to compare the effect sizes of resting-state and hypercapnia induced BOLD signal changes in the detection of hemodynamic impairment. The second aim of the study was to assess the dependence of BOLD signal variability on vCBV. Materials and methods Fifteen patients with internal carotid artery occlusive disease and 15 matched healthy controls were included in this study. The BOLD signal was derived from a dual-echo gradient-echo echo-planar sequence during hypercapnia (HC) and hyperoxia (HO) gas modulations. BOLD (fractional) amplitude of low frequency fluctuations ((f)ALFF) was compared to HC-BOLD, BOLD response delays derived from time delay analysis and ΔBOLD in response to progressively increasing HC. Effect sizes (i.e. the standard mean difference between patients and controls) were calculated. HO-BOLD was used to estimate vCBV, and its contribution to the variability in rsBOLD signal was evaluated. Results The effect sizes of ALFF and fALFF (0.61 and 0.72) were lower than the effect sizes related to hypercapnia-based hemodynamic assessment analysis; 1.62, 1.56 and 0.90 for HC-BOLD, BOLD response delays and ΔBOLD in response to progressively increasing HC. A moderate relation was found between (f)ALFF and HC-BOLD in controls (R2 of 0.61 and 0.42), but this relation decreased in patients (R2 of 0.33 and 0.15). (f)ALFF did not differ between patients and controls whereas HC-BOLD did (p < 0.005). The ΔBOLD response to progressively increasing HC was significantly different in between patients and controls for ΔEtCO2 values ≥ 2 mmHg (at +2 mmHg F(1, 18) = 5.85, p = 0.026). Up to 31% and 53% of the variance in the ALFF and HC-BOLD spatial distribution could be explained by HO-BOLD. Conclusion ALFF and fALFF demonstrated a moderate effect size to detect hemodynamic impairment whereas the effect size was large for methods employing a hypercapnia-based vascular stress stimulus. Based on our analysis of BOLD signal change as a response to a progressively increasing hypercapnia stimulus we can argue that a hypercapnia stimulus of at least 2 mmHg above baseline EtCO2 is necessary to evaluate hemodynamic impairment. We also demonstrated that a substantial amount of information imbedded in the rsBOLD and HC-BOLD was explained by HO-BOLD. HO-BOLD can serve as a proxy for vCBV and this thus indicates that one should be careful when adopting these techniques in disease cases with compromised CBV.
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Affiliation(s)
- Jill B De Vis
- National Institute of Health (NIH) / National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA.
| | - Alex A Bhogal
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
| | - Esben T Petersen
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands; Danish Research Centre for Magnetic Resonance, Hvidovre Hospital, Denmark.
| | - Jeroen C W Siero
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands; Spinoza Centre for Neuroimaging Amsterdam, Amsterdam, the Netherlands.
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34
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Liu P, De Vis JB, Lu H. Cerebrovascular reactivity (CVR) MRI with CO2 challenge: A technical review. Neuroimage 2018; 187:104-115. [PMID: 29574034 DOI: 10.1016/j.neuroimage.2018.03.047] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/06/2018] [Accepted: 03/19/2018] [Indexed: 11/16/2022] Open
Abstract
Cerebrovascular reactivity (CVR) is an indicator of cerebrovascular reserve and provides important information about vascular health in a range of brain conditions and diseases. Unlike steady-state vascular parameters, such as cerebral blood flow (CBF) and cerebral blood volume (CBV), CVR measures the ability of cerebral vessels to dilate or constrict in response to challenges or maneuvers. Therefore, CVR mapping requires a physiological challenge while monitoring the corresponding hemodynamic changes in the brain. The present review primarily focuses on methods that use CO2 inhalation as a physiological challenge while monitoring changes in hemodynamic MRI signals. CO2 inhalation has been increasingly used in CVR mapping in recent literature due to its potency in causing vasodilation, rapid onset and cessation of the effect, as well as advances in MRI-compatible gas delivery apparatus. In this review, we first discuss the physiological basis of CVR mapping using CO2 inhalation. We then review the methodological aspects of CVR mapping, including gas delivery apparatus, the timing paradigm of the breathing challenge, the MRI imaging sequence, and data analysis. In addition, we review alternative approaches for CVR mapping that do not require CO2 inhalation.
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Affiliation(s)
- Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States.
| | - Jill B De Vis
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, 21287, United States; F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, 21205, United States
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35
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Fierstra J, van Niftrik C, Warnock G, Wegener S, Piccirelli M, Pangalu A, Esposito G, Valavanis A, Buck A, Luft A, Bozinov O, Regli L. Staging Hemodynamic Failure With Blood Oxygen-Level–Dependent Functional Magnetic Resonance Imaging Cerebrovascular Reactivity. Stroke 2018; 49:621-629. [DOI: 10.1161/strokeaha.117.020010] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 11/03/2017] [Accepted: 11/29/2017] [Indexed: 12/20/2022]
Abstract
Background and Purpose—
Increased stroke risk correlates with hemodynamic failure, which can be assessed with (
15
O-)H
2
O positron emission tomography (PET) cerebral blood flow (CBF) measurements. This gold standard technique, however, is not established for routine clinical imaging. Standardized blood oxygen-level–dependent (BOLD) functional magnetic resonance imaging+CO
2
is a noninvasive and potentially widely applicable tool to assess whole-brain quantitative cerebrovascular reactivity (CVR). We examined the agreement between the 2 imaging modalities and hypothesized that quantitative CVR can be a surrogate imaging marker to assess hemodynamic failure.
Methods—
Nineteen data sets of subjects with chronic cerebrovascular steno-occlusive disease (age, 60±11 years; 4 women) and unilaterally impaired perfusion reserve on Diamox-challenged (
15
O-)H
2
O PET were studied and compared with a standardized BOLD functional magnetic resonance imaging+CO
2
examination within 6 weeks (8±19 days). Agreement between quantitative CBF- and CVR-based perfusion reserve was assessed. Hemodynamic failure was staged according to PET findings: stage 0: normal CBF, normal perfusion reserve; stage I: normal CBF, decreased perfusion reserve; and stage II: decreased CBF, decreased perfusion reserve. The BOLD CVR data set of the same subjects was then matched to the corresponding stage of hemodynamic failure.
Results—
PET-based stage I versus stage II could also be clearly separated with BOLD CVR measurements (CVR for stage I 0.11 versus CVR for stage II −0.03;
P
<0.01). Hemispheric and middle cerebral artery territory difference analyses (ie, affected versus unaffected side) showed a significant correlation for CVR impairment in the affected hemisphere and middle cerebral artery territory (
P
<0.01,
R
2
=0.47 and
P
=0.02,
R
2
= 0.25, respectively).
Conclusions—
BOLD CVR corresponded well to CBF perfusion reserve measurements obtained with (
15
O-)H
2
O-PET, especially for detecting hemodynamic failure in the affected hemisphere and middle cerebral artery territory and for identifying hemodynamic failure stage II. BOLD CVR may, therefore, be considered for prospective studies assessing stroke risk in patients with chronic cerebrovascular steno-occlusive disease, in particular because it can potentially be implemented in routine clinical imaging.
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Affiliation(s)
- Jorn Fierstra
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Christiaan van Niftrik
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Geoffrey Warnock
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Susanne Wegener
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Marco Piccirelli
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Athina Pangalu
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Giuseppe Esposito
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Antonios Valavanis
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Alfred Buck
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Andreas Luft
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Oliver Bozinov
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
| | - Luca Regli
- From the Departments of Neurosurgery (J.F., C.v.N., G.E., O.B., L.R.), Neuroradiology (M.P., A.V.), Neurology (S.W., A.L.), Pharmacology and Toxicology (G.W.), and Nuclear Medicine (A.B.), Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Switzerland
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Chen PC, Shoa KH, Jao JC, Hsiao CC. Dynamic magnetic resonance imaging of carbogen challenge on awake rabbit brain at 1.5T. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2018; 26:997-1009. [PMID: 30223421 DOI: 10.3233/xst-180395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
BACKGROUND Anesthesia may alter the cellular components contributing to the magnetic resonance imaging (MRI) signal intensities. Developing awake animal models to evaluate cerebral function has grown in importance. OBJECTIVE To investigate a noninvasive strategy for dynamic MRI (dMRI) of awake rabbits during carbogen challenge. METHODS A nonmetallic assistive device with a self-adhering wrap secure procedure was developed for the head fixation of awake rabbits. Multi-shot gradient echo echo-planar imaging sequence was applied for the dMRI on a 1.5 T clinical MRI scanner with a quadrature head coil. The carbogen challenge pattern was applied in a sequence of air - carbogen - air - carbogen - air. Twelve scans were performed for each block of carbogen challenge. T2-weighted fast-spin echo and T1-weighted gradient echo sequences were performed before and after dMRI to evaluate the head position shifts. The whole dMRI scan time was about 30 minutes. RESULTS The position shift of 8 rabbits in the x-and y-direction was less than 3%. The average MRI signal intensities (SI) from the 8 rabbits during carbogen challenge was fitted well using exponential growth and decay functions. The average MRI SI increase due to carbogen inhaling was 1.51%. CONCLUSIONS The proposed strategy for head dMRI on an awake rabbit during carbogen challenge is feasible.
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Affiliation(s)
- Po-Chou Chen
- Department of Biomedical Engineering, I-Shou University, Kaohsiung City, Taiwan, ROC
| | - Kuan-Hsiung Shoa
- Department of Radiology, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC
| | - Jo-Chi Jao
- Department of Medical Imaging and Radiological Sciences, College of Health Sciences, Kaohsiung Medical University, Kaohsiung City, Taiwan, ROC
| | - Chia-Chi Hsiao
- Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung City, Taiwan, ROC
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Lants SK, Watchmaker JM, Juttukonda MR, Davis LT, Donahue MJ, Fusco MR. Treatment of Progressive Herpes Zoster-Induced Vasculopathy with Surgical Revascularization: Effects on Cerebral Hemodynamics. World Neurosurg 2017; 111:132-138. [PMID: 29274451 DOI: 10.1016/j.wneu.2017.12.087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Herpes zoster ophthalmicus (HZO) is caused by reactivation of the herpes simplex virus in the trigeminal nerve. HZO-initiated cerebral vasculopathy is well characterized; however, there are no documented cases that report the efficacy of surgical revascularization for improving cerebral hemodynamics following progressive HZO-induced vasculopathy. We present a case in which quantitative anatomic and hemodynamic imaging were performed longitudinally before and after surgical revascularization in a patient with HZO and vasculopathic changes. CASE DESCRIPTION A 57-year-old female with history of right-sided HZO presented with left-sided hemiparesis and dysarthria and multiple acute infarcts. Angiography performed serially over a 2-month duration revealed progressive middle cerebral artery stenosis, development of new moyamoya-like lenticulostriate collaterals, and evidence of fibromuscular dysplasia in cervical portions of the internal carotid artery. Hemodynamic imaging revealed right hemisphere decreased blood flow and cerebrovascular reserve capacity. In addition to medical therapy, right-sided surgical revascularization was performed with the intent to reestablish blood flow. Follow-up imaging 13 months post revascularization demonstrated improved blood flow and vascular reserve capacity in the operative hemisphere, which paralleled symptom resolution. CONCLUSIONS HZO can lead to progressive, symptomatic intracranial stenoses. This report suggests that surgical revascularization techniques can improve cerebral hemodynamics and symptomatology in patients with aggressive disease when medical management is unsuccessful; similar procedures could be considered in managing HZO patients with advanced or progressive vasculopathy.
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Affiliation(s)
- Sarah K Lants
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
| | - Jennifer M Watchmaker
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Larry T Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Psychiatry, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee, USA
| | - Matthew R Fusco
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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38
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Liu S, Cai J, Ge F, Yue W. The risk of ischemic events increased in patients with asymptomatic carotid stenosis with decreased cerebrovascular reserve. J Investig Med 2017; 65:1028-1032. [DOI: 10.1136/jim-2017-000443] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/08/2017] [Indexed: 11/03/2022]
Abstract
Identifying high-risk patients with asymptomatic carotid stenosis (ACS) is necessary regardless of whether intensive medical therapy or aggressive treatment is applied. In order to assess the relationship between cerebrovascular reserve (CVR) measured by perfusion CT with inhalation of CO2and the risk of ischemic events in ACS, this long-term follow-up study was conducted. Forty-five patients with ACS who underwent the examination of CVR measured by perfusion CT with inhalation of CO2were collected and followed-up for at least 5 years. The primary end point was the occurrence of ipsilateral cerebral ischemic events. HRs and their 95% CI were calculated by Kaplan-Meier survival analysis and Cox regression models. The mean follow-up time was 68.7±10.7 months (40.0–84.0 months). 13 (28.9%) ipsilateral ischemic events were observed. The annual risk of ipsilateral ischemic events was 4.8%. Kaplan-Meier survival analysis and univariate Cox regression analysis indicated that patients with less CVR experienced more ischemic events (p=0.006 and p=0.013, respectively), which was confirmed by multiple Cox regression analysis (p=0.012). CVR measured by perfusion CT may potentially be the factor which can predict the risk of ipsilateral ischemic events in patients with ACS. Multidisciplinary management is necessary for these high-risk patients.
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Jefferson AL, Gifford KA, Acosta LMY, Bell SP, Donahue MJ, Davis LT, Gottlieb J, Gupta DK, Hohman TJ, Lane EM, Libon DJ, Mendes LA, Niswender K, Pechman KR, Rane S, Ruberg FL, Su YR, Zetterberg H, Liu D. The Vanderbilt Memory & Aging Project: Study Design and Baseline Cohort Overview. J Alzheimers Dis 2017; 52:539-59. [PMID: 26967211 DOI: 10.3233/jad-150914] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Vascular health factors frequently co-occur with Alzheimer's disease (AD). A better understanding of how systemic vascular and cerebrovascular health intersects with clinical and pathological AD may inform prevention and treatment opportunities. OBJECTIVE To establish the Vanderbilt Memory & Aging Project, a case-control longitudinal study investigating vascular health and brain aging, and describe baseline methodology and participant characteristics. METHODS From September 2012 to November 2014, 335 participants age 60- 92 were enrolled, including 168 individuals with mild cognitive impairment (MCI, 73±8 years, 41% female) and 167 age-, sex-, and race-matched cognitively normal controls (NC, 72±7 years, 41% female). At baseline, participants completed a physical and frailty examination, fasting blood draw, neuropsychological assessment, echocardiogram, cardiac MRI, and brain MRI. A subset underwent 24-hour ambulatory blood pressure monitoring and lumbar puncture for cerebrospinal fluid (CSF) collection. RESULTS As designed, participant groups were comparable for age (p = 0.31), sex (p = 0.95), and race (p = 0.65). MCI participants had greater Framingham Stroke Risk Profile scores (p = 0.008), systolic blood pressure values (p = 0.008), and history of left ventricular hypertrophy (p = 0.04) than NC participants. As expected, MCI participants performed worse on all neuropsychological measures (p-values < 0.001), were more likely to be APOEɛ4 carriers (p = 0.02), and had enhanced CSF biomarkers, including lower Aβ42 (p = 0.02), higher total tau (p = 0.004), and higher p-tau (p = 0.02) compared to NC participants. CONCLUSION Diverse sources of baseline and longitudinal data will provide rich opportunities to investigate pathways linking vascular and cerebrovascular health, clinical and pathological AD, and neurodegeneration contributing to novel strategies to delay or prevent cognitive decline.
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Affiliation(s)
- Angela L Jefferson
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Katherine A Gifford
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lealani Mae Y Acosta
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Susan P Bell
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.,Center for Quality Aging, Division of General Internal Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Neurology, Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA.,Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - L Taylor Davis
- Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - JoAnn Gottlieb
- Vanderbilt Institute for Clinical & Translational Research, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Deepak K Gupta
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Timothy J Hohman
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Elizabeth M Lane
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David J Libon
- Rowan University - School of Osteopathic Medicine, Department of Geriatrics and Gerontology, New Jersey Institute for Successful Aging, Stratford, NJ, USA
| | - Lisa A Mendes
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kevin Niswender
- Tennessee Valley Healthcare System, Division of Diabetes, Endocrinology, & Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kimberly R Pechman
- Vanderbilt Memory & Alzheimer's Center, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Swati Rane
- Radiology, University of Washington Medical Center, Seattle, WA, USA
| | - Frederick L Ruberg
- Boston University School of Medicine, Boston, MA, USA.,Section of Cardiovascular Medicine, Boston Medical Center, Boston, MA, USA
| | - Yan Ru Su
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Deparment of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
| | - Dandan Liu
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
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40
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Cogswell PM, Davis TL, Strother MK, Faraco CC, Scott AO, Jordan LC, Fusco MR, Frederick BD, Hendrikse J, Donahue MJ. Impact of vessel wall lesions and vascular stenoses on cerebrovascular reactivity in patients with intracranial stenotic disease. J Magn Reson Imaging 2017; 46:1167-1176. [PMID: 28061015 DOI: 10.1002/jmri.25602] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/06/2016] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To compare cerebrovascular reactivity (CVR) and CVR lagtimes in flow territories perfused by vessels with vs. without proximal arterial wall disease and/or stenosis, separately in patients with atherosclerotic and nonatherosclerotic (moyamoya) intracranial stenosis. MATERIALS AND METHODS Atherosclerotic and moyamoya patients with >50% intracranial stenosis and <70% cervical stenosis underwent angiography, vessel wall imaging (VWI), and CVR-weighted imaging (n = 36; vessel segments evaluated = 396). Angiography and VWI were evaluated for stenosis locations and vessel wall lesions. Maximum CVR and CVR lagtime were contrasted between vascular territories with and without proximal intracranial vessel wall lesions and stenosis, and a Wilcoxon rank-sum was test used to determine differences (criteria: corrected two-sided P < 0.05). RESULTS CVR lagtime was prolonged in territories with vs. without a proximal vessel wall lesion or stenosis for both patient groups: moyamoya (CVR lagtime = 45.5 sec ± 14.2 sec vs. 35.7 sec ± 9.7 sec, P < 0.001) and atherosclerosis (CVR lagtime = 38.2 sec ± 9.1 sec vs. 35.0 sec ± 7.2 sec, P = 0.001). For reactivity, a significant decrease in maximum CVR in the moyamoya group only (maximum CVR = 9.8 ± 2.2 vs. 12.0 ± 2.4, P < 0.001) was observed. CONCLUSION Arterial vessel wall lesions detected on noninvasive, noncontrast intracranial VWI in patients with intracranial stenosis correlate on average with tissue-level impairment on CVR-weighted imaging. LEVEL OF EVIDENCE 4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1167-1176.
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Affiliation(s)
- Petrice M Cogswell
- Department of Radiology, Vanderbilt University, Nashville, Tennessee, USA
| | - Taylor L Davis
- Department of Radiology, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Carlos C Faraco
- Department of Radiology, Vanderbilt University, Nashville, Tennessee, USA
| | - Allison O Scott
- Department of Radiology, Vanderbilt University, Nashville, Tennessee, USA
| | - Lori C Jordan
- Department of Pediatrics, Vanderbilt University, Nashville, Tennessee, USA.,Department of Neurology, Vanderbilt University, Nashville, Tennessee, USA
| | - Matthew R Fusco
- Department of Neurosurgery, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Manus J Donahue
- Department of Radiology, Vanderbilt University, Nashville, Tennessee, USA.,Department of Neurology, Vanderbilt University, Nashville, Tennessee, USA.,Department of Psychiatry, Vanderbilt University, Nashville, Tennessee, USA
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41
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Cerebrovascular reactivity mapping without gas challenges. Neuroimage 2016; 146:320-326. [PMID: 27888058 DOI: 10.1016/j.neuroimage.2016.11.054] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/16/2016] [Accepted: 11/21/2016] [Indexed: 11/22/2022] Open
Abstract
Cerebrovascular reactivity (CVR), the ability of cerebral vessels to dilate or constrict, has been shown to provide valuable information in the diagnosis and treatment evaluation of patients with various cerebrovascular conditions. CVR mapping is typically performed using hypercapnic gas inhalation as a vasoactive challenge while collecting BOLD images, but the inherent need of gas inhalation and the associated apparatus setup present a practical obstacle in applying it in routine clinical use. Therefore, we aimed to develop a new method to map CVR using resting-state BOLD data without the need of gas inhalation. This approach exploits the natural variation in respiration and measures its influence on BOLD MRI signal. In this work, we first identified a surrogate of the arterial CO2 fluctuation during spontaneous breathing from the global BOLD signal. Second, we tested the feasibility and reproducibility of the proposed approach to use the above-mentioned surrogate as a regressor to estimate voxel-wise CVR. Third, we validated the "resting-state CVR map" with a conventional CVR map obtained with hypercapnic gas inhalation in healthy volunteers. Finally, we tested the utility of this new approach in detecting abnormal CVR in a group of patients with Moyamoya disease, and again validated the results using the conventional gas inhalation method. Our results showed that global BOLD signal fluctuation in the frequency range of 0.02-0.04Hz contains the most prominent contribution from natural variation in arterial CO2. The CVR map calculated using this signal as a regressor is reproducible across runs (ICC=0.91±0.06), and manifests a strong spatial correlation with results measured with a conventional hypercapnia-based method in healthy subjects (r=0.88, p<0.001). We also found that resting-state CVR was able to identify vasodilatory deficit in patients with steno-occlusive disease, the spatial pattern of which matches that obtained using the conventional gas method (r=0.71±0.18). These results suggest that CVR obtained with resting-state BOLD may be a useful alternative in detecting vascular deficits in clinical applications when gas challenge is not feasible.
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42
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Donahue MJ, Strother MK, Lindsey KP, Hocke LM, Tong Y, Frederick BD. Time delay processing of hypercapnic fMRI allows quantitative parameterization of cerebrovascular reactivity and blood flow delays. J Cereb Blood Flow Metab 2016; 36:1767-1779. [PMID: 26661192 PMCID: PMC5076782 DOI: 10.1177/0271678x15608643] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/29/2015] [Indexed: 11/17/2022]
Abstract
Blood oxygenation level-dependent fMRI contrast depends on the volume and oxygenation of blood flowing through the circulatory system. The effects on image intensity depend temporally on the arrival of blood within a voxel, and signal can be monitored during the time course of such blood flow. It has been previously shown that the passage of global endogenous variations in blood volume and oxygenation can be tracked as blood passes through the brain by determining the strength and peak time lag of their cross-correlation with blood oxygenation level-dependent data. By manipulating blood composition using transient hypercarbia and hyperoxia, we can induce much larger oxygenation and volume changes in the blood oxygenation level-dependent signal than result from natural endogenous fluctuations. This technique was used to examine cerebrovascular parameters in healthy subjects (n = 8) and subjects with intracranial stenosis (n = 22), with a subgroup of intracranial stenosis subjects scanned before and after surgical revascularization (n = 6). The halfwidth of cross-correlation lag times in the brain was larger in IC stenosis subjects (21.21 ± 14.22 s) than in healthy control subjects (8.03 ± 3.67), p < 0.001, and was subsequently reduced in regions that co-localized with surgical revascularization. These data show that blood circulatory timing can be measured robustly and longitudinally throughout the brain using simple respiratory challenges.
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Affiliation(s)
- Manus J Donahue
- Department of Radiology, Vanderbilt Medical Center, Nashville, TN, USA Department of Neurology, Vanderbilt Medical Center, Nashville, TN, USA Department of Psychiatry, Vanderbilt Medical Center, Nashville, TN, USA Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
| | - Megan K Strother
- Department of Radiology, Vanderbilt Medical Center, Nashville, TN, USA
| | - Kimberly P Lindsey
- Brain Imaging Center, McLean Hospital, Belmont, MA, USA Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Lia M Hocke
- Brain Imaging Center, McLean Hospital, Belmont, MA, USA Department of Bioengineering, Tufts University, Medford, MA, USA
| | - Yunjie Tong
- Brain Imaging Center, McLean Hospital, Belmont, MA, USA Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Blaise deB Frederick
- Brain Imaging Center, McLean Hospital, Belmont, MA, USA Department of Psychiatry, Harvard Medical School, Boston, MA, USA
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43
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Liu P, Welch BG, Li Y, Gu H, King D, Yang Y, Pinho M, Lu H. Multiparametric imaging of brain hemodynamics and function using gas-inhalation MRI. Neuroimage 2016; 146:715-723. [PMID: 27693197 DOI: 10.1016/j.neuroimage.2016.09.063] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/21/2016] [Accepted: 09/26/2016] [Indexed: 12/30/2022] Open
Abstract
Diagnosis and treatment monitoring of cerebrovascular diseases routinely require hemodynamic imaging of the brain. Current methods either only provide part of the desired information or require the injection of multiple exogenous agents. In this study, we developed a multiparametric imaging scheme for the imaging of brain hemodynamics and function using gas-inhalation MRI. The proposed technique uses a single MRI scan to provide simultaneous measurements of baseline venous cerebral blood volume (vCBV), cerebrovascular reactivity (CVR), bolus arrival time (BAT), and resting-state functional connectivity (fcMRI). This was achieved with a novel, concomitant O2 and CO2 gas inhalation paradigm, rapid MRI image acquisition with a 9.3min BOLD sequence, and an advanced algorithm to extract multiple hemodynamic information from the same dataset. In healthy subjects, CVR and vCBV values were 0.23±0.03%/mmHg and 0.0056±0.0006%/mmHg, respectively, with a strong correlation (r=0.96 for CVR and r=0.91 for vCBV) with more conventional, separate acquisitions that take twice the scan time. In patients with Moyamoya syndrome, CVR in the stenosis-affected flow territories (typically anterior-cerebral-artery, ACA, and middle-cerebral-artery, MCA, territories) was significantly lower than that in posterior-cerebral-artery (PCA), which typically has minimal stenosis, flow territories (0.12±0.06%/mmHg vs. 0.21±0.05%/mmHg, p<0.001). BAT of the gas bolus was significantly longer (p=0.008) in ACA/MCA territories, compared to PCA, and the maps were consistent with the conventional contrast-enhanced CT perfusion method. FcMRI networks were robustly identified from the gas-inhalation MRI data after factoring out the influence of CO2 and O2 on the signal time course. The spatial correspondence between the gas-data-derived fcMRI maps and those using a separate, conventional fcMRI scan was excellent, showing a spatial correlation of 0.58±0.17 and 0.64±0.20 for default mode network and primary visual network, respectively. These findings suggest that advanced gas-inhalation MRI provides reliable measurements of multiple hemodynamic parameters within a clinically acceptable imaging time and is suitable for patient examinations.
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Affiliation(s)
- Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Babu G Welch
- Department of Neurological Surgery, UT Southwestern Medical Center, Dallas, TX 75390, United States; Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, United States
| | - Yang Li
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States; Biomedical Engineering Graduate Program, UT Southwestern Medical Center, Dallas, TX 75390, United States
| | - Hong Gu
- Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, United States
| | - Darlene King
- Department of Neurological Surgery, UT Southwestern Medical Center, Dallas, TX 75390, United States
| | - Yihong Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, United States
| | - Marco Pinho
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States.
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44
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Donahue MJ, Juttukonda MR, Watchmaker JM. Noise concerns and post-processing procedures in cerebral blood flow (CBF) and cerebral blood volume (CBV) functional magnetic resonance imaging. Neuroimage 2016; 154:43-58. [PMID: 27622397 DOI: 10.1016/j.neuroimage.2016.09.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/22/2016] [Accepted: 09/03/2016] [Indexed: 01/19/2023] Open
Abstract
Functional neuroimaging with blood oxygenation level-dependent (BOLD) contrast has emerged as the most popular method for evaluating qualitative changes in brain function in humans. At typical human field strengths (1.5-3.0T), BOLD contrast provides a measure of changes in transverse water relaxation rates in and around capillary and venous blood, and as such provides only a surrogate marker of brain function that depends on dynamic changes in hemodynamics (e.g., cerebral blood flow and volume) and metabolism (e.g., oxygen extraction fraction and the cerebral metabolic rate of oxygen consumption). Alternative functional neuroimaging methods that are specifically sensitive to these constituents of the BOLD signal are being developed and applied in a growing number of clinical and neuroscience applications of quantitative cerebral physiology. These methods require additional considerations for interpreting and quantifying their contrast responsibly. Here, an overview of two popular methods, arterial spin labeling and vascular space occupancy, is presented specifically in the context of functional neuroimaging. Appropriate post-processing and experimental acquisition strategies are summarized with the motivation of reducing sensitivity to noise and unintended signal sources and improving quantitative accuracy of cerebral hemodynamics.
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Affiliation(s)
- Manus J Donahue
- Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA; Neurology, Vanderbilt University School of Medicine, Nashville, TN, USA; Psychiatry, Vanderbilt University School of Medicine, Nashville, TN, USA.
| | - Meher R Juttukonda
- Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jennifer M Watchmaker
- Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
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45
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Oldag A, Neumann J, Goertler M, Hinrichs H, Heinze HJ, Kupsch A, Sweeney-Reed CM, Kopitzki K. Near-infrared spectroscopy and transcranial sonography to evaluate cerebral autoregulation in middle cerebral artery steno-occlusive disease. J Neurol 2016; 263:2296-2301. [PMID: 27544503 DOI: 10.1007/s00415-016-8262-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/06/2016] [Accepted: 08/08/2016] [Indexed: 10/21/2022]
Abstract
The measurement of autoregulatory delay by near-infrared spectroscopy (NIRS) has been proposed as an alternative technique to assess cerebral autoregulation, which is routinely assessed via transcranial Doppler sonography (TCD) in most centers. Comparitive studies of NIRS and TCD, however, are largely missing. We investigated whether cerebrovascular reserve (CVR), as assessed via TCD, correlates with the delay of the autoregulatory response to changes in arterial blood pressure (ABP) as assessed by NIRS, i.e., if impaired upstream vasomotor reactivity is reflected by downstream cortical autoregulation. Twenty patients with unilateral high-grade steno-occlusion of the middle cerebral artery (MCA) underwent bilateral multichannel NIRS of the cortical MCA distributions over a period of 6 min while breathing at a constant rate of 6 cycles/min to induce stable oscillations in ABP. The phase shift φ between ABP and cortical blood oxygenation was calculated as a measure of autoregulatory latency. In a subgroup of 13 patients, CO2 reactivity of the MCAs was determined by TCD to assess CVR in terms of normalized autoregulatory response (NAR). Mean phase shift between ABP and blood oxygenation was significantly increased over the hemisphere ipsilateral to the steno-occlusion (n = 20, p = 0.042). The interhemispheric difference Δφ in phase shift was significantly larger in patients with markedly diminished or exhausted CVR (NAR < 10) than in patients with normal NAR values (NAR ≥ 10) (p = 0.007). Within the MCA core distribution territory, a strong correlation existed between Δφ and CO2 reactivity of the affected MCA (n = 13, r = -0.78, p = 0.011). NIRS may provide an alternative or supplementary approach to evaluate cerebral autoregulation in risk assessment of ischemic events in steno-occlusive disease of cerebral arteries, especially in patients with insufficient bone windows for TCD.
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Affiliation(s)
- Andreas Oldag
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Jens Neumann
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Michael Goertler
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany
| | - Hermann Hinrichs
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Andreas Kupsch
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Catherine M Sweeney-Reed
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Klaus Kopitzki
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany. .,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany.
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46
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Bhogal AA, De Vis JB, Siero JCW, Petersen ET, Luijten PR, Hendrikse J, Philippens MEP, Hoogduin H. The BOLD cerebrovascular reactivity response to progressive hypercapnia in young and elderly. Neuroimage 2016; 139:94-102. [PMID: 27291492 DOI: 10.1016/j.neuroimage.2016.06.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 05/30/2016] [Accepted: 06/08/2016] [Indexed: 12/01/2022] Open
Abstract
Blood Oxygenation Level Dependent (BOLD) imaging in combination with vasoactive stimuli can be used to probe cerebrovascular reactivity (CVR). Characterizing the healthy, age-related changes in the BOLD-CVR response can provide a reference point from which to distinguish abnormal CVR from the otherwise normal effects of ageing. Using a computer controlled gas delivery system, we examine differences in BOLD-CVR response to progressive hypercapnia between 16 young (28±3years, 9 female) and 30 elderly subjects (66±4years, 13 female). Furthermore, we incorporate baseline T2* information to broaden our interpretation of the BOLD-CVR response. Significant age-related differences were observed. Grey matter CVR at 7mmHg above resting PetCO2 was lower amongst elderly (0.19±0.06%ΔBOLD/mmHg) as compared to young subjects (0.26±0.07%ΔBOLD/mmHg). White matter CVR at 7mmHg above baseline PetCO2 showed no significant difference between young (0.04±0.02%ΔBOLD/mmHg) and elderly subjects (0.05±0.03%ΔBOLD/mmHg). We saw no significant differences in the BOLD signal response to progressive hypercapnia between male and female subjects in either grey or white matter. The observed differences in the healthy BOLD-CVR response could be explained by age-related changes in vascular mechanical properties.
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Affiliation(s)
- Alex A Bhogal
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Jill B De Vis
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen C W Siero
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Esben T Petersen
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital, Hvidovre, Denmark
| | - Peter R Luijten
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Hans Hoogduin
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
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Roach BA, Donahue MJ, Davis LT, Faraco CC, Arteaga D, Chen SC, Ladner TR, Scott AO, Strother MK. Interrogating the Functional Correlates of Collateralization in Patients with Intracranial Stenosis Using Multimodal Hemodynamic Imaging. AJNR Am J Neuroradiol 2016; 37:1132-8. [PMID: 27056428 DOI: 10.3174/ajnr.a4758] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 11/28/2015] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND PURPOSE The importance of collateralization for maintaining adequate cerebral perfusion is increasingly recognized. However, measuring collateral flow noninvasively has proved elusive. The aim of this study was to assess correlations among baseline perfusion and arterial transit time artifacts, cerebrovascular reactivity, and the presence of collateral vessels on digital subtraction angiography. MATERIALS AND METHODS The relationship between the presence of collateral vessels on arterial spin-labeling MR imaging and DSA was compared with blood oxygen level-dependent MR imaging measures of hypercapnic cerebrovascular reactivity in patients with symptomatic intracranial stenosis (n = 18). DSA maps were reviewed by a neuroradiologist and assigned the following scores: 1, collaterals to the periphery of the ischemic site; 2, complete irrigation of the ischemic bed via collateral flow; and 3, normal antegrade flow. Arterial spin-labeling maps were scored according to the following: 0, low signal; 1, moderate signal with arterial transit artifacts; 2, high signal with arterial transit artifacts; and 3, normal signal. RESULTS In regions with normal-to-high signal on arterial spin-labeling, collateral vessel presence on DSA strongly correlated with declines in cerebrovascular reactivity (as measured on blood oxygen level-dependent MR imaging, P < .001), most notably in patients with nonatherosclerotic disease. There was a trend toward increasing cerebrovascular reactivity with increases in the degree of collateralization on DSA (P = .082). CONCLUSIONS Collateral vessels may have fundamentally different vasoreactivity properties from healthy vessels, a finding that is observed most prominently in nonatherosclerotic disease and, to a lesser extent, in atherosclerotic disease.
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Affiliation(s)
- B A Roach
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - M J Donahue
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.) Neurology (M.J.D.) Psychiatry (M.J.D.)
| | - L T Davis
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - C C Faraco
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - D Arteaga
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - S-C Chen
- the Vanderbilt Center for Quantitative Sciences (S.-C.C.), Vanderbilt Medical Center, Nashville, Tennessee
| | - T R Ladner
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - A O Scott
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
| | - M K Strother
- From the Departments of Radiology and Radiological Sciences (B.A.R., M.J.D., L.T.D., C.C.F., D.A., T.R.L., A.O.S., M.K.S.)
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48
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Ladner TR, Donahue MJ, Arteaga DF, Faraco CC, Roach BA, Davis LT, Jordan LC, Froehler MT, Strother MK. Prior Infarcts, Reactivity, and Angiography in Moyamoya Disease (PIRAMD): a scoring system for moyamoya severity based on multimodal hemodynamic imaging. J Neurosurg 2016; 126:495-503. [PMID: 26967789 DOI: 10.3171/2015.11.jns15562] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Quantification of the severity of vasculopathy and its impact on parenchymal hemodynamics is a necessary prerequisite for informing management decisions and evaluating intervention response in patients with moyamoya. The authors performed digital subtraction angiography and noninvasive structural and hemodynamic MRI, and they outline a new classification system for patients with moyamoya that they have named Prior Infarcts, Reactivity, and Angiography in Moyamoya Disease (PIRAMD). METHODS Healthy control volunteers (n = 11; age 46 ± 12 years [mean ± SD]) and patients (n = 25; 42 ± 13.5 years) with angiographically confirmed moyamoya provided informed consent and underwent structural (T1-weighted, T2-weighted, FLAIR, MR angiography) and hemodynamic (T2*- and cerebral blood flow-weighted) 3-T MRI. Cerebrovascular reactivity (CVR) in the internal carotid artery territory was assessed using susceptibility-weighted MRI during a hypercapnic stimulus. Only hemispheres without prior revascularization were assessed. Each hemisphere was considered symptomatic if localizing signs were present on neurological examination and/or there was a history of transient ischemic attack with symptoms referable to that hemisphere. The PIRAMD factor weighting versus symptomatology was optimized using binary logistic regression and receiver operating characteristic curve analysis with bootstrapping. The PIRAMD finding was scored from 0 to 10. For each hemisphere, 1 point was assigned for prior infarct, 3 points for reduced CVR, 3 points for a modified Suzuki Score ≥ Grade II, and 3 points for flow impairment in ≥ 2 of 7 predefined vascular territories. Hemispheres were divided into 3 severity grades based on total PIRAMD score, as follows: Grade 1, 0-5 points; Grade 2, 6-9 points; and Grade 3, 10 points. RESULTS In 28 of 46 (60.9%) hemispheres the findings met clinical symptomatic criteria. With decreased CVR, the odds ratio of having a symptomatic hemisphere was 13 (95% CI 1.1-22.6, p = 0.002). The area under the curve for individual PIRAMD factors was 0.67-0.72, and for the PIRAMD grade it was 0.845. There were 0/8 (0%), 10/18 (55.6%), and 18/20 (90%) symptomatic PIRAMD Grade 1, 2, and 3 hemispheres, respectively. CONCLUSIONS A scoring system for total impairment is proposed that uses noninvasive MRI parameters. This scoring system correlates with symptomatology and may provide a measure of hemodynamic severity in moyamoya, which could be used for guiding management decisions and evaluating intervention response.
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Affiliation(s)
| | | | | | | | | | | | - Lori C Jordan
- Division of Pediatric Neurology, Department of Pediatrics; and
| | - Michael T Froehler
- Departments of Neurology and Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee
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49
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Kazan SM, Mohammadi S, Callaghan MF, Flandin G, Huber L, Leech R, Kennerley A, Windischberger C, Weiskopf N. Vascular autorescaling of fMRI (VasA fMRI) improves sensitivity of population studies: A pilot study. Neuroimage 2016; 124:794-805. [PMID: 26416648 PMCID: PMC4655941 DOI: 10.1016/j.neuroimage.2015.09.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 09/11/2015] [Accepted: 09/17/2015] [Indexed: 11/04/2022] Open
Abstract
The blood oxygenation level-dependent (BOLD) signal is widely used for functional magnetic resonance imaging (fMRI) of brain function in health and disease. The statistical power of fMRI group studies is significantly hampered by high inter-subject variance due to differences in baseline vascular physiology. Several methods have been proposed to account for physiological vascularization differences between subjects and hence improve the sensitivity in group studies. However, these methods require the acquisition of additional reference scans (such as a full resting-state fMRI session or ASL-based calibrated BOLD). We present a vascular autorescaling (VasA) method, which does not require any additional reference scans. VasA is based on the observation that slow oscillations (<0.1Hz) in arterial blood CO2 levels occur naturally due to changes in respiration patterns. These oscillations yield fMRI signal changes whose amplitudes reflect the blood oxygenation levels and underlying local vascularization and vascular responsivity. VasA estimates proxies of the amplitude of these CO2-driven oscillations directly from the residuals of task-related fMRI data without the need for reference scans. The estimates are used to scale the amplitude of task-related fMRI responses, to account for vascular differences. The VasA maps compared well to cerebrovascular reactivity (CVR) maps and cerebral blood volume maps based on vascular space occupancy (VASO) measurements in four volunteers, speaking to the physiological vascular basis of VasA. VasA was validated in a wide variety of tasks in 138 volunteers. VasA increased t-scores by up to 30% in specific brain areas such as the visual cortex. The number of activated voxels was increased by up to 200% in brain areas such as the orbital frontal cortex while still controlling the nominal false-positive rate. VasA fMRI outperformed previously proposed rescaling approaches based on resting-state fMRI data and can be readily applied to any task-related fMRI data set, even retrospectively.
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Affiliation(s)
- Samira M Kazan
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom.
| | - Siawoosh Mohammadi
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Martina F Callaghan
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Guillaume Flandin
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Laurentius Huber
- NMR-Unit, Max Planck Institute for Human Cognition and Brain Sciences, Leipzig, Germany
| | - Robert Leech
- Cognitive, Clinical and Computational Neuroimaging Lab, Imperial College, Hammersmith Hospital, University of London, London W12 0NN, United Kingdom
| | - Aneurin Kennerley
- Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Christian Windischberger
- MR Centre of Excellence, Centre for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, Vienna A-1090, Austria
| | - Nikolaus Weiskopf
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom; Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
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50
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The cumulative influence of hyperoxia and hypercapnia on blood oxygenation and R*₂. J Cereb Blood Flow Metab 2015; 35:2032-42. [PMID: 26174329 PMCID: PMC4671125 DOI: 10.1038/jcbfm.2015.168] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 06/09/2015] [Accepted: 06/11/2015] [Indexed: 01/01/2023]
Abstract
Cerebrovascular reactivity (CVR)-weighted blood-oxygenation-level-dependent magnetic resonance imaging (BOLD-MRI) experiments are frequently used in conjunction with hyperoxia. Owing to complex interactions between hyperoxia and hypercapnia, quantitative effects of these gas mixtures on BOLD responses, blood and tissue R2*, and blood oxygenation are incompletely understood. Here we performed BOLD imaging (3 T; TE/TR=35/2,000 ms; spatial resolution=3 × 3 × 3.5 mm(3)) in healthy volunteers (n=12; age=29±4.1 years) breathing (i) room air (RA), (ii) normocapnic-hyperoxia (95% O2/5% N2, HO), (iii) hypercapnic-normoxia (5% CO2/21% O2/74% N2, HC-NO), and (iv) hypercapnic-hyperoxia (5% CO2/95% O2, HC-HO). For HC-HO, experiments were performed with separate RA and HO baselines to control for changes in O2. T2-relaxation-under-spin-tagging MRI was used to calculate basal venous oxygenation. Signal changes were quantified and established hemodynamic models were applied to quantify vasoactive blood oxygenation, blood-water R2*, and tissue-water R2*. In the cortex, fractional BOLD changes (stimulus/baseline) were HO/RA=0.011±0.007; HC-NO/RA=0.014±0.004; HC-HO/HO=0.020±0.008; and HC-HO/RA=0.035±0.010; for the measured basal venous oxygenation level of 0.632, this led to venous blood oxygenation levels of 0.660 (HO), 0.665 (HC-NO), and 0.712 (HC-HO). Interleaving a HC-HO stimulus with HO baseline provided a smaller but significantly elevated BOLD response compared with a HC-NO stimulus. Results provide an outline for how blood oxygenation differs for several gas stimuli and provides quantitative information on how hypercapnic BOLD CVR and R2* are altered during hyperoxia.
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