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Woods JG, Achten E, Asllani I, Bolar DS, Dai W, Detre JA, Fan AP, Fernández-Seara MA, Golay X, Günther M, Guo J, Hernandez-Garcia L, Ho ML, Juttukonda MR, Lu H, MacIntosh BJ, Madhuranthakam AJ, Mutsaerts HJ, Okell TW, Parkes LM, Pinter N, Pinto J, Qin Q, Smits M, Suzuki Y, Thomas DL, Van Osch MJP, Wang DJJ, Warnert EAH, Zaharchuk G, Zelaya F, Zhao M, Chappell MA. Recommendations for quantitative cerebral perfusion MRI using multi-timepoint arterial spin labeling: Acquisition, quantification, and clinical applications. Magn Reson Med 2024. [PMID: 38594906 DOI: 10.1002/mrm.30091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 02/09/2024] [Accepted: 03/07/2024] [Indexed: 04/11/2024]
Abstract
Accurate assessment of cerebral perfusion is vital for understanding the hemodynamic processes involved in various neurological disorders and guiding clinical decision-making. This guidelines article provides a comprehensive overview of quantitative perfusion imaging of the brain using multi-timepoint arterial spin labeling (ASL), along with recommendations for its acquisition and quantification. A major benefit of acquiring ASL data with multiple label durations and/or post-labeling delays (PLDs) is being able to account for the effect of variable arterial transit time (ATT) on quantitative perfusion values and additionally visualize the spatial pattern of ATT itself, providing valuable clinical insights. Although multi-timepoint data can be acquired in the same scan time as single-PLD data with comparable perfusion measurement precision, its acquisition and postprocessing presents challenges beyond single-PLD ASL, impeding widespread adoption. Building upon the 2015 ASL consensus article, this work highlights the protocol distinctions specific to multi-timepoint ASL and provides robust recommendations for acquiring high-quality data. Additionally, we propose an extended quantification model based on the 2015 consensus model and discuss relevant postprocessing options to enhance the analysis of multi-timepoint ASL data. Furthermore, we review the potential clinical applications where multi-timepoint ASL is expected to offer significant benefits. This article is part of a series published by the International Society for Magnetic Resonance in Medicine (ISMRM) Perfusion Study Group, aiming to guide and inspire the advancement and utilization of ASL beyond the scope of the 2015 consensus article.
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Affiliation(s)
- Joseph G Woods
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Center for Functional Magnetic Resonance Imaging, Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Eric Achten
- Ghent Institute for Functional and Metabolic Imaging (GIfMI), Ghent University, Ghent, Belgium
| | - Iris Asllani
- Department of Neuroscience, University of Sussex, Brighton, UK
- Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, New York, USA
| | - Divya S Bolar
- Center for Functional Magnetic Resonance Imaging, Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Weiying Dai
- Department of Computer Science, State University of New York at Binghamton, Binghamton, New York, USA
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Audrey P Fan
- Department of Biomedical Engineering, University of California Davis, Davis, California, USA
- Department of Neurology, University of California Davis, Davis, California, USA
| | - María A Fernández-Seara
- Department of Radiology, Clínica Universidad de Navarra, Pamplona, Spain
- IdiSNA, Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain
| | - Xavier Golay
- UCL Queen Square Institute of Neurology, University College London, London, UK
- Gold Standard Phantoms, Sheffield, UK
| | - Matthias Günther
- Imaging Physics, Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
- Department of Physics and Electrical Engineering, University of Bremen, Bremen, Germany
| | - Jia Guo
- Department of Bioengineering, University of California Riverside, Riverside, California, USA
| | | | - Mai-Lan Ho
- Department of Radiology, University of Missouri, Columbia, Missouri, USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Bradley J MacIntosh
- Hurvitz Brain Sciences Program, Centre for Brain Resilience & Recovery, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Computational Radiology & Artificial Intelligence unit, Oslo University Hospital, Oslo, Norway
| | - Ananth J Madhuranthakam
- Department of Radiology and Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Henk-Jan Mutsaerts
- Department of Radiology and Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Brain Imaging, Amsterdam, The Netherlands
| | - Thomas W Okell
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Laura M Parkes
- School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, UK
| | - Nandor Pinter
- Dent Neurologic Institute, Buffalo, New York, USA
- University at Buffalo Neurosurgery, Buffalo, New York, USA
| | - Joana Pinto
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Qin Qin
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Marion Smits
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Medical Delta, Delft, The Netherlands
- Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, The Netherlands
| | - Yuriko Suzuki
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - David L Thomas
- Department of Brain Repair and Rehabilitation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Matthias J P Van Osch
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Danny J J Wang
- Laboratory of FMRI Technology (LOFT), Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA
| | - Esther A H Warnert
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, The Netherlands
| | - Greg Zaharchuk
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK
| | - Moss Zhao
- Department of Radiology, Stanford University, Stanford, California, USA
- Maternal & Child Health Research Institute, Stanford University, Stanford, California, USA
| | - Michael A Chappell
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, UK
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Damestani NL, Jacoby J, Michel CB, Rashid B, Salat DH, Juttukonda MR. MRI Assessment of Cerebral White Matter Microvascular Hemodynamics Across the Adult Lifespan. J Magn Reson Imaging 2024. [PMID: 38179863 DOI: 10.1002/jmri.29217] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 12/18/2023] [Accepted: 12/18/2023] [Indexed: 01/06/2024] Open
Abstract
BACKGROUND Changes in cerebral hemodynamics with aging are important for understanding age-related variation in neuronal health. While many prior studies have focused on gray matter, less is known regarding white matter due in part to measurement challenges related to the lower vascular density in white matter. PURPOSE To investigate the impact of age and sex on white matter hemodynamics in a Human Connectome Project in Aging (HCP-A) cohort using tract-based spatial statistics (TBSS). STUDY TYPE Retrospective cross-sectional. POPULATION Six hundred seventy-eight typically aging individuals (381 female), aged 36-100 years. FIELD STRENGTH/SEQUENCE Multi-delay pseudo-continuous arterial spin labeling (ASL) and diffusion-weighted pulsed-gradient spin-echo echo planar imaging sequences at 3.0 T. ASSESSMENT A skeleton of mean fractional anisotropy (FA) was produced using TBSS. This skeleton was used to project ASL-derived cerebral blood flow (CBF) and arterial transit time (ATT) measures onto white matter tracts. STATISTICAL TESTS General linear models were applied to white matter FA, CBF, and ATT maps, while covarying for age and sex. Threshold-free cluster enhancement multiple comparisons correction was performed for the effects of age and sex, thresholded at PFWE < 0.05. CBF, ATT, and FA were compared between sex for each tract using analysis of covariance, with multiple comparisons correction for the number of tracts at PFDR < 0.05. RESULTS Significantly lower white matter CBF and significantly prolonged white matter ATTs were associated with older age. These effects were widespread across tracts for ATT. Significant (PFDR < 0.05) sex differences in ATT were observed across all tracts, and significant sex differences in CBF were observed in all tracts except the bilateral uncinate fasciculus. Females demonstrated significantly higher CBF compared to males across the lifespan. Few tracts demonstrated significant sex differences in FA. DATA CONCLUSION This study identified significant sex- and age-associated differences in white matter hemodynamics across tracts. EVIDENCE LEVEL 3 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Nikou L Damestani
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - John Jacoby
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Christa B Michel
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Barnaly Rashid
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
- Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, Massachusetts, USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
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Yetim E, Jacoby J, Damestani NL, Lovely AE, Salat DH, Juttukonda MR. Mean Arterial Pressure and Cerebral Hemodynamics Across The Lifespan: A Cross-Sectional Study From Human Connectome Project-Aging. J Magn Reson Imaging 2023; 58:1892-1900. [PMID: 37040498 PMCID: PMC10564963 DOI: 10.1002/jmri.28722] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 04/13/2023] Open
Abstract
BACKGROUND Cerebral perfusion is directly affected by systemic blood pressure, which has been shown to be negatively correlated with cerebral blood flow (CBF). The impact of aging on these effects is not fully understood. PURPOSE To determine whether the relationship between mean arterial pressure (MAP) and cerebral hemodynamics persists throughout the lifespan. STUDY TYPE Retrospective, cross-sectional study. POPULATION Six hundred and sixty-nine participants from the Human Connectome Project-Aging ranging between 36 and 100+ years and without a major neurological disorder. FIELD STRENGTH/SEQUENCE Imaging data was acquired at 3.0 Tesla using a 32-channel head coil. CBF and arterial transit time (ATT) were measured by multi-delay pseudo-continuous arterial spin labeling. ASSESSMENT The relationships between cerebral hemodynamic parameters and MAP were evaluated globally in gray and white matter and regionally using surface-based analysis in the whole group, separately within different age groups (young: <60 years; younger-old: 60-79 years; oldest-old: ≥80 years). STATISTICAL TESTS Chi-squared, Kruskal-Wallis, ANOVA, Spearman rank correlation and linear regression models. The general linear model setup in FreeSurfer was used for surface-based analyses. P < 0.05 was considered significant. RESULTS Globally, there was a significant negative correlation between MAP and CBF in both gray (ρ = -0.275) and white matter (ρ = -0.117). This association was most prominent in the younger-old [gray matter CBF (β = -0.271); white matter CBF (β = -0.241)]. In surface-based analyses, CBF exhibited a widespread significant negative association with MAP throughout the brain, whereas a limited number of regions showed significant prolongation in ATT with higher MAP. The associations between regional CBF and MAP in the younger-old showed a different topographic pattern in comparison to young subjects. DATA CONCLUSION These observations further emphasize the importance of cardiovascular health in mid-to-late adulthood for healthy brain aging. The differences in the topographic pattern with aging indicate a spatially heterogeneous relationship between high blood pressure and CBF. LEVEL OF EVIDENCE 3 TECHNICAL EFFICACY STAGE: 3.
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Affiliation(s)
- Ezgi Yetim
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
| | - John Jacoby
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
| | - Nikou L. Damestani
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
- Department of Radiology, Harvard Medical School, Boston MA
| | - Allison E. Lovely
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
| | - David H. Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
- Department of Radiology, Harvard Medical School, Boston MA
- Neuroimaging for Veterans Center, VA Boston Healthcare System, Boston MA
| | - Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown MA
- Department of Radiology, Harvard Medical School, Boston MA
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Rashid B, Glasser MF, Nichols T, Van Essen D, Juttukonda MR, Schwab NA, Greve DN, Yacoub E, Lovely A, Terpstra M, Harms MP, Bookheimer SY, Ances BM, Salat DH, Arnold SE. Cardiovascular and metabolic health is associated with functional brain connectivity in middle-aged and older adults: Results from the Human Connectome Project-Aging study. Neuroimage 2023; 276:120192. [PMID: 37247763 PMCID: PMC10330931 DOI: 10.1016/j.neuroimage.2023.120192] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/15/2023] [Accepted: 05/24/2023] [Indexed: 05/31/2023] Open
Abstract
Several cardiovascular and metabolic indicators, such as cholesterol and blood pressure have been associated with altered neural and cognitive health as well as increased risk of dementia and Alzheimer's disease in later life. In this cross-sectional study, we examined how an aggregate index of cardiovascular and metabolic risk factor measures was associated with correlation-based estimates of resting-state functional connectivity (FC) across a broad adult age-span (36-90+ years) from 930 volunteers in the Human Connectome Project Aging (HCP-A). Increased (i.e., worse) aggregate cardiometabolic scores were associated with reduced FC globally, with especially strong effects in insular, medial frontal, medial parietal, and superior temporal regions. Additionally, at the network-level, FC between core brain networks, such as default-mode and cingulo-opercular, as well as dorsal attention networks, showed strong effects of cardiometabolic risk. These findings highlight the lifespan impact of cardiovascular and metabolic health on whole-brain functional integrity and how these conditions may disrupt higher-order network integrity.
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Affiliation(s)
- Barnaly Rashid
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States.
| | - Matthew F Glasser
- Washington University School of Medicine, St. Louis, MO, United States
| | | | - David Van Essen
- Washington University School of Medicine, St. Louis, MO, United States
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States
| | - Nadine A Schwab
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States
| | - Douglas N Greve
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States
| | - Essa Yacoub
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Allison Lovely
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States
| | | | - Michael P Harms
- Washington University in St. Louis, St. Louis, MO, United States
| | | | - Beau M Ances
- Washington University School of Medicine, St. Louis, MO, United States; Washington University in St. Louis, St. Louis, MO, United States
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States.
| | - Steven E Arnold
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 149 13th St., Charlestown, MA 02129, United States; Harvard Medical School, Boston, MA, United States.
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Damestani NL, Jacoby J, Yadav SM, Lovely AE, Michael A, Terpstra M, Eshghi M, Rashid B, Cruchaga C, Salat DH, Juttukonda MR. Cortical hemodynamics are dependent on age, sex and APOE genotype - A Human Connectome Project Aging study. Neuroimage 2023; 275:120167. [PMID: 37187365 DOI: 10.1016/j.neuroimage.2023.120167] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 05/02/2023] [Accepted: 05/11/2023] [Indexed: 05/17/2023] Open
Abstract
Altered blood flow in the human brain is characteristic of typical aging. However, numerous factors contribute to inter-individual variation in patterns of blood flow throughout the lifespan. To better understand the mechanisms behind such variation, we studied how sex and APOE genotype, a primary genetic risk factor for Alzheimer's disease (AD), influence associations between age and brain perfusion measures. We conducted a cross-sectional study of 562 participants from the Human Connectome Project - Aging (36 to >90 years of age). We found widespread associations between age and vascular parameters, where increasing age was associated with regional decreases in cerebral blood flow (CBF) and increases in arterial transit time (ATT). When grouped by sex and APOE genotype, interactions between group and age demonstrated that females had relatively greater CBF and lower ATT compared to males. Females carrying the APOEε4 allele showed the strongest association between CBF decline and ATT incline with age. This demonstrates that sex and genetic risk for AD modulate age-associated patterns of cerebral perfusion measures.
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Affiliation(s)
- Nikou L Damestani
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA.
| | - John Jacoby
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Shrikanth M Yadav
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Allison E Lovely
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Aurea Michael
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Melissa Terpstra
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | | | - Barnaly Rashid
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; NeuroGenomics and Informatics Center, Washington University School of Medicine, St. Louis, MO, USA; Hope Center for Neurologic Diseases, Washington University in St. Louis, St. Louis, MO, USA
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston MA, USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, 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: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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7
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Rashid B, Glasser MF, Nichols T, Van Essen D, Juttukonda MR, Schwab NA, Yacoub E, Lovely A, Terpstra M, Harms MP, Bookheimer SY, Ances BM, Arnold SE, Salat DH. Default‐mode connectivity mediates the association between cardiovascular and metabolic risks and cognition: a pilot study. Alzheimers Dement 2022. [DOI: 10.1002/alz.067131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Barnaly Rashid
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | | | | | - David Van Essen
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - Nadine A Schwab
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - Essa Yacoub
- Center for Magnetic Resonance Research, University of Minnesota Minneapolis MN USA
| | - Allison Lovely
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | | | - Michael P Harms
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - Susan Y. Bookheimer
- David Geffen School of Medicine at University of California Los Angeles Los Angeles CA USA
| | - Beau M Ances
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - Steven E. Arnold
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
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8
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Rashid B, Glasser MF, Nichols T, Van Essen D, Juttukonda MR, Schwab NA, Yacoub E, Lovely A, Terpstra M, Harms MP, Bookheimer SY, Ances BM, Salat DH, Arnold SE. Associations between default‐mode functional connectivity and distress, cardiovascular and metabolic risks and cognition in middle aged and older adults. Alzheimers Dement 2022. [DOI: 10.1002/alz.067094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Barnaly Rashid
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | | | | | - David Van Essen
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - Nadine A Schwab
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - Essa Yacoub
- Center for Magnetic Resonance Research, University of Minnesota Minneapolis MN USA
| | - Allison Lovely
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | | | - Michael P Harms
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - Susan Y. Bookheimer
- David Geffen School of Medicine at University of California Los Angeles Los Angeles CA USA
| | - Beau M Ances
- Washington University in St. Louis School of Medicine St. Louis MO USA
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
| | - Steven E. Arnold
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown MA USA
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9
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Juttukonda MR, Vaclavu L, Kirkham FJ, Fields ME, Bush AM. Editorial: Cerebral oxygen supply and demand in sickle cell disease: Evidence of local ischemia despite global hyperemia. Front Physiol 2022; 13:1079889. [PMID: 36479342 PMCID: PMC9720841 DOI: 10.3389/fphys.2022.1079889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 11/04/2022] [Indexed: 12/01/2023] Open
Affiliation(s)
- Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
| | - Lena Vaclavu
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Fenella J. Kirkham
- Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Melanie E. Fields
- Division of Pediatric Hematology/Oncology, Washington University in St. Louis, Saint Louis, MO, United States
| | - Adam M. Bush
- Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX, United States
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10
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Juttukonda MR, Stephens KA, Yen YF, Howard CM, Polimeni JR, Rosen BR, Salat DH. Oxygen extraction efficiency and white matter lesion burden in older adults exhibiting radiological evidence of capillary shunting. J Cereb Blood Flow Metab 2022; 42:1933-1943. [PMID: 35673981 PMCID: PMC9536117 DOI: 10.1177/0271678x221105986] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/19/2022] [Accepted: 05/14/2022] [Indexed: 01/18/2023]
Abstract
White matter lesions (WML) have been linked to cognitive decline in aging as well as in Alzheimer's disease. While hypoperfusion is frequently considered a cause of WMLs due to the resulting reduction in oxygen availability to brain tissue, such reductions could also be caused by impaired oxygen exchange. Here, we tested the hypothesis that venous hyperintense signal (VHS) in arterial spin labeling (ASL) magnetic resonance imaging (MRI) may represent a marker of impaired oxygen extraction in aging older adults. In participants aged 60-80 years (n = 30), we measured cerebral blood flow and VHS with arterial spin labeling, maximum oxygen extraction fraction (OEFmax) with dynamic susceptibility contrast, and WML volume with T1-weighted MRI. We found a significant interaction between OEFmax and VHS presence on WML volume (p = 0.02), where lower OEFmax was associated with higher WML volume in participants with VHS, and higher OEFmax was associated with higher WML volume in participants without VHS. These results indicate that VHS in perfusion-weighted ASL data may represent a distinct cerebrovascular aging pattern involving oxygen extraction inefficiency as well as hypoperfusion.
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Affiliation(s)
- Meher R Juttukonda
- 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
| | - Kimberly A Stephens
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Yi-Fen Yen
- 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
| | - Casey M Howard
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Jonathan R Polimeni
- 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
- Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Bruce R Rosen
- 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
- Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David H Salat
- 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
- Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, USA
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11
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Juttukonda MR, Almaktoum R, Stephens KA, Yochim KM, Salat DH. Characterizing white matter hemodynamic markers of lesion burden and cognitive function using arterial spin labeling MRI. Alzheimers Dement 2021. [DOI: 10.1002/alz.055493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
- Harvard Medical School Boston MA USA
| | | | | | | | - David H. Salat
- Harvard Medical School Boston MA USA
- Massachusetts General Hospital Charlestown MA USA
- Neuroimaging Research for Veterans Center VA Boston Healthcare System Boston MA USA
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12
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Salat DH, Almaktoum R, Helfgott JS, Helmer KG, Jacoby J, Jang I, Juttukonda MR, Loveley A, Moreno T, Peled N, Stufflebeam S, Greve DN. Baseline neuroimaging characteristics in the randomized pivotal study of renew NCP‐5 for the treatment of mild cognitive impairment (MCI) due to Alzheimer's disease or mild dementia of the Alzheimer's type. Alzheimers Dement 2021. [DOI: 10.1002/alz.057740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- David H. Salat
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Randa Almaktoum
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | | | - Karl G. Helmer
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - John Jacoby
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Ikbeom Jang
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Allison Loveley
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Tom Moreno
- Renew Research LLC Farmington Hills MI USA
| | - Noam Peled
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Steven Stufflebeam
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Douglas N. Greve
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown MA USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Chen Y, Ying C, Binkley MM, Juttukonda MR, Flores S, Laforest R, Benzinger TL, An H. Deep learning-based T1-enhanced selection of linear attenuation coefficients (DL-TESLA) for PET/MR attenuation correction in dementia neuroimaging. Magn Reson Med 2021; 86:499-513. [PMID: 33559218 PMCID: PMC8091494 DOI: 10.1002/mrm.28689] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 12/23/2020] [Accepted: 12/29/2020] [Indexed: 12/31/2022]
Abstract
PURPOSE The accuracy of existing PET/MR attenuation correction (AC) has been limited by a lack of correlation between MR signal and tissue electron density. Based on our finding that longitudinal relaxation rate, or R1 , is associated with CT Hounsfield unit in bone and soft tissues in the brain, we propose a deep learning T1 -enhanced selection of linear attenuation coefficients (DL-TESLA) method to incorporate quantitative R1 for PET/MR AC and evaluate its accuracy and longitudinal test-retest repeatability in brain PET/MR imaging. METHODS DL-TESLA uses a 3D residual UNet (ResUNet) for pseudo-CT (pCT) estimation. With a total of 174 participants, we compared PET AC accuracy of DL-TESLA to 3 other methods adopting similar 3D ResUNet structures but using UTE R 2 ∗ , or Dixon, or T1 -MPRAGE as input. With images from 23 additional participants repeatedly scanned, the test-retest differences and within-subject coefficient of variation of standardized uptake value ratios (SUVR) were compared between PET images reconstructed using either DL-TESLA or CT for AC. RESULTS DL-TESLA had (1) significantly lower mean absolute error in pCT, (2) the highest Dice coefficients in both bone and air, (3) significantly lower PET relative absolute error in whole brain and various brain regions, (4) the highest percentage of voxels with a PET relative error within both ±3% and ±5%, (5) similar to CT test-retest differences in SUVRs from the cerebrum and mean cortical (MC) region, and (6) similar to CT within-subject coefficient of variation in cerebrum and MC. CONCLUSION DL-TESLA demonstrates excellent PET/MR AC accuracy and test-retest repeatability.
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Affiliation(s)
- Yasheng Chen
- Dept. of Neurology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Chunwei Ying
- Dept. of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Michael M. Binkley
- Dept. of Neurology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Meher R. Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Dept. of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
- Dept. of Radiology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Shaney Flores
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Richard Laforest
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Tammie L.S. Benzinger
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
| | - Hongyu An
- Dept. of Neurology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
- Dept. of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63110, USA
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri 63110, USA
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15
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Trujillo P, Roman OC, Hay KR, Juttukonda MR, Yan Y, Kang H, Paranjape SY, Garland EM, Shibao CA, Biaggioni I, Donahue MJ, Claassen DO. Elevated cerebral blood flow in patients with pure autonomic failure. Clin Auton Res 2021; 31:405-414. [PMID: 33677714 DOI: 10.1007/s10286-021-00792-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 02/24/2021] [Indexed: 12/19/2022]
Abstract
PURPOSE Pure autonomic failure (PAF) results from an impaired peripheral autonomic nervous system, and clinical symptoms present with orthostatic hypotension. While the impact on cardiovascular indices of orthostatic intolerance are well-characterized, more limited information is available regarding cerebral hemodynamic dysfunction in PAF. The objective of this study was to test the hypothesis that cerebral blood flow (CBF) is reduced in PAF, and to quantify the relationship between CBF and clinical indicators of disease severity, including peripheral supine arterial blood pressure. METHODS Participants with PAF (n = 17) and age- and sex-matched normotensive healthy controls (n = 17) were examined using established clinical rating scales, cardiovascular autonomic function tests, and 3T MRI measurements of CBF. CBF-weighted images were also used to determine the prevalence of venous hyperintensities from the major dural sinuses as evidence of abnormal capillary flow. Nonparametric tests and general linear models were used to evaluate differences and correlations between study variables. RESULTS Gray matter CBF was higher in PAF (51.1 ± 13.4 mL/100 g/min) compared to controls (42.9 ± 6.5 mL/100 g/min, p = 0.007). Venous hyperintensities were more prevalent in PAF relative to controls, and the presence and degree of venous hyperintensities was associated with higher mean CBF (p = 0.027). In PAF participants, CBF and supine systolic blood pressure were inversely related (Spearman's rho = -0.545, p = 0.024). CONCLUSIONS Findings suggest that PAF patients may exhibit elevated CBF and provide evidence that this condition exerts a hemodynamic impact in the central nervous system.
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Affiliation(s)
- Paula Trujillo
- Department of Neurology, Vanderbilt University Medical Center, 1161 21st Ave South A-0118, Nashville, TN, 37232, USA
| | - Olivia C Roman
- Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Kaitlyn R Hay
- Department of Neurology, Vanderbilt University Medical Center, 1161 21st Ave South A-0118, Nashville, TN, 37232, USA
| | - Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Yan Yan
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Sachin Y Paranjape
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Emily M Garland
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Cyndya A Shibao
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Italo Biaggioni
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Neurology, Vanderbilt University Medical Center, 1161 21st Ave South A-0118, Nashville, TN, 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daniel O Claassen
- Department of Neurology, Vanderbilt University Medical Center, 1161 21st Ave South A-0118, Nashville, TN, 37232, USA.
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16
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Juttukonda MR, Donahue MJ, Waddle SL, Davis LT, Lee CA, Patel NJ, Pruthi S, Kassim AA, Jordan LC. Reduced oxygen extraction efficiency in sickle cell anemia patients with evidence of cerebral capillary shunting. J Cereb Blood Flow Metab 2021; 41:546-560. [PMID: 32281458 PMCID: PMC7922746 DOI: 10.1177/0271678x20913123] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Arterial spin labeling (ASL) magnetic resonance imaging (MRI) utilizes arterial blood water as an endogenous contrast agent to provide a quantitative measure of cerebral blood flow (CBF). Recently, hyperintense signal within dural venous sinuses in ASL images of sickle cell anemia (SCA) patients has been shown to be consistent with elevated flow velocities and may indicate capillary shunting and reduced oxygen extraction. Here, we performed oxygen extraction fraction (OEF) and CBF measurements in adults (cumulative n = 114) with (n = 69) and without (n = 45) SCA to test the hypothesis that hyperintense venous ASL signal is associated with reduced OEF. Higher categorical scores of shunting on ASL MRI were associated with lower OEF in participants with silent cerebral infarcts or white matter hyperintensities (p = 0.003), but not in those without lesions (p = 0.551). These findings indicate that venous hyperintense signal in ASL images in SCA patients may represent a marker of capillary-level disturbances in oxygen exchange efficiency and small vessel pathology.
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Affiliation(s)
- Meher R Juttukonda
- 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.,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
| | - Spencer L Waddle
- 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
| | - Chelsea A Lee
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J Patel
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sumit Pruthi
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adetola A Kassim
- Department of Medicine, Division of Hematology-Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lori C Jordan
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
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17
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Juttukonda MR, Li B, Almaktoum R, Stephens KA, Yochim KM, Yacoub E, Buckner RL, Salat DH. Characterizing cerebral hemodynamics across the adult lifespan with arterial spin labeling MRI data from the Human Connectome Project-Aging. Neuroimage 2021; 230:117807. [PMID: 33524575 PMCID: PMC8185881 DOI: 10.1016/j.neuroimage.2021.117807] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/09/2020] [Accepted: 01/20/2021] [Indexed: 12/17/2022] Open
Abstract
Arterial spin labeling (ASL) magnetic resonance imaging (MRI) has become a popular approach for studying cerebral hemodynamics in a range of disorders and has recently been included as part of the Human Connectome Project-Aging (HCP-A). Due to the high spatial resolution and multiple post-labeling delays, ASL data from HCP-A holds promise for localization of hemodynamic signals not only in gray matter but also in white matter. However, gleaning information about white matter hemodynamics with ASL is challenging due in part to longer blood arrival times in white matter compared to gray matter. In this work, we present an analytical approach for deriving measures of cerebral blood flow (CBF) and arterial transit times (ATT) from the ASL data from HCP-A and report on gray and white matter hemodynamics in a large cohort (n = 234) of typically aging adults (age 36–90 years). Pseudo-continuous ASL data were acquired with labeling duration = 1500 ms and five post-labeling delays = 200 ms, 700 ms, 1200, 1700 ms, and 2200 ms. ATT values were first calculated on a voxel-wise basis through normalized cross-correlation analysis of the acquired signal time course in that voxel and an expected time course based on an acquisition-specific Bloch simulation. CBF values were calculated using a two-compartment model and with age-appropriate blood water longitudinal relaxation times. Using this approach, we found that white matter CBF reduces (ρ = 0.39) and white matter ATT elongates (ρ = 0.42) with increasing age (p < 0.001). In addition, CBF is lower and ATTs are longer in white matter compared to gray matter across the adult lifespan (Wilcoxon signed-rank tests; p < 0.001). We also found sex differences with females exhibiting shorter white matter ATTs than males, independently of age (Wilcoxon rank-sum test; p < 0.001). Finally, we have shown that CBF and ATT values are spatially heterogeneous, with significant differences in cortical versus subcortical gray matter and juxtacortical versus periventricular white matter. These results serve as a characterization of normative physiology across the human lifespan against which hemodynamic impairment due to cerebrovascular or neurodegenerative diseases could be compared in future studies.
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Affiliation(s)
- Meher R Juttukonda
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States; Department of Radiology, Harvard Medical School, Boston, MA, United States.
| | - Binyin Li
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States; Department of Neurology, Ruijin Hospital & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Randa Almaktoum
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States
| | - Kimberly A Stephens
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States
| | - Kathryn M Yochim
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States
| | - Essa Yacoub
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnessota, Minneapolis, MN, United States
| | - Randy L Buckner
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States; Department of Psychology, Harvard University, Cambridge, MA, United States; Department of Neuroscience, Harvard University, Cambridge, MA, United States
| | - David H Salat
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 Thirteenth Street, Suite, 2301, Charlestown 02129, MA, United States; Department of Radiology, Harvard Medical School, Boston, MA, United States; Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, United States
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18
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Cogswell PM, Lants SK, Davis LT, Juttukonda MR, Fusco MR, Donahue MJ. Vessel Wall and Lumen Features in North American Moyamoya Patients. Clin Neuroradiol 2020; 30:545-552. [PMID: 31388688 PMCID: PMC7245731 DOI: 10.1007/s00062-019-00819-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/16/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE To apply intracranial vessel wall imaging (VWI) to determine changes in vessel wall characteristics between North American moyamoya patients and controls, as well as with standard clinical measures of moyamoya disease severity. METHODS North American moyamoya patients and controls underwent intracranial 3.0 T VWI. Moyamoya patients also underwent digital subtraction angiography (DSA), from which modified Suzuki scores (mSS) were calculated. Lumen and outer vessel wall diameters of the supraclinoid internal carotid arteries (ICAs) and basilar artery on VWI were measured by two readers from which wall thickness was calculated. Controls and moyamoya patients were compared in logistic regression using disease category (moyamoya or none) as the dependent variable and wall thickness, age, gender, and side as the explanatory variables (significance: two-sided p < 0.05). In moyamoya patients, regression was performed with mSS as the dependent variable and wall thickness, age, gender, and side as the explanatory variables. Analyses were repeated for each lumen diameter and outer vessel wall diameter in place of wall thickness. RESULTS Patients with moyamoya (n = 23, gender = 3/20 male/female; age = 43 ± 12 years) and controls (n = 23, gender = 3/20 male/female, age = 43 ± 13 years) were included. Moyamoya patients showed a significantly smaller ICA lumen and outer vessel wall diameter compared to controls (p < 0.05) but no significant change in vessel wall thickness. Similarly, ICA lumen and outer vessel wall diameters decreased with increasing mSS (p < 0.05). CONCLUSION Findings suggest decreased ICA lumen and outer vessel wall diameters, but no significant difference in wall thickness, between patients and controls. Lumen and outer vessel wall diameters also decreased with disease severity.
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Affiliation(s)
- Petrice M Cogswell
- Department of Radiology, Mayo Clinic, 200 First St SW, 55905, Rochester, MN, USA.
| | - Sarah K Lants
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - L Taylor Davis
- 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
| | - Matthew R Fusco
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
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19
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Johnson SE, McKnight CD, Lants SK, Juttukonda MR, Fusco M, Chitale R, Donahue PC, Claassen DO, Donahue MJ. Choroid plexus perfusion and intracranial cerebrospinal fluid changes after angiogenesis. J Cereb Blood Flow Metab 2020; 40:1658-1671. [PMID: 31500523 PMCID: PMC7370367 DOI: 10.1177/0271678x19872563] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent studies have provided evidence that cortical brain ischemia may influence choroid plexus function, and such communication may be mediated by either traditional CSF circulation pathways and/or a possible glymphatic pathway. Here we investigated the hypothesis that improvements in arterial health following neoangiogenesis alter (i) intracranial CSF volume and (ii) choroid plexus perfusion in humans. CSF and tissue volume measurements were obtained from T1-weighted MRI, and cortical and choroid plexus perfusion were obtained from perfusion-weighted arterial spin labeling MRI, in patients with non-atherosclerotic intracranial stenosis (e.g. Moyamoya). Measurements were repeated after indirect surgical revascularization, which elicits cortical neoangiogenesis near the revascularization site (n = 23; age = 41.8 ± 13.4 years), or in a cohort of participants at two time points without interval surgeries (n = 10; age = 41.7 ± 10.7 years). Regression analyses were used to evaluate dependence of perfusion and volume on state (time 1 vs. 2). Post-surgery, neither CSF nor tissue volumes changed significantly. In surgical patients, cortical perfusion increased and choroid plexus perfusion decreased after surgery; in participants without surgeries, cortical perfusion reduced and choroid plexus perfusion increased between time points. Findings are discussed in the context of a homeostatic mechanism, whereby arterial health, paravascular flow, and/or ischemia can affect choroid plexus perfusion.
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Affiliation(s)
- Skylar E Johnson
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Colin D McKnight
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Sarah K Lants
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Matthew Fusco
- Department of Neurosurgery, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Rohan Chitale
- Department of Neurosurgery, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Paula C Donahue
- Department of Physical Medicine and Rehabilitation, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Daniel O Claassen
- Department of Neurology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA
- Department of Neurology, Vanderbilt University School of Medicine, Nashville, TN, USA
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville, TN, USA
- Manus J Donahue, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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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] [What about the content of this article? (0)] [Affiliation(s)] [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] [What about the content of this article? (0)] [Affiliation(s)] [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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Jordan LC, Juttukonda MR, Kassim AA, DeBaun MR, Davis LT, Pruthi S, Patel NJ, Lee CA, Waddle SL, Donahue MJ. Haploidentical bone marrow transplantation improves cerebral hemodynamics in adults with sickle cell disease. Am J Hematol 2019; 94:E155-E158. [PMID: 30838684 DOI: 10.1002/ajh.25455] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 02/27/2019] [Accepted: 03/03/2019] [Indexed: 01/17/2023]
Affiliation(s)
- Lori C. Jordan
- Division of Pediatric Neurology, Department of PediatricsVanderbilt University Medical Center Nashville Tennessee
- Department of NeurologyVanderbilt University Medical Center Nashville Tennessee
| | - Meher R. Juttukonda
- Department of Radiology and Radiological SciencesVanderbilt University Medical Center Nashville Tennessee
| | - Adetola A. Kassim
- Division of Hematology, Department of MedicineVanderbilt University Medical Center Nashville Tennessee
| | - Michael R. DeBaun
- Division of Hematology/Oncology, Department of PediatricsVanderbilt University Medical Center Nashville Tennessee
| | - Larry T. Davis
- Department of Radiology and Radiological SciencesVanderbilt University Medical Center Nashville Tennessee
| | - Sumit Pruthi
- Department of Radiology and Radiological SciencesVanderbilt University Medical Center Nashville Tennessee
| | - Niral J. Patel
- Division of Pediatric Neurology, Department of PediatricsVanderbilt University Medical Center Nashville Tennessee
| | - Chelsea A. Lee
- Division of Pediatric Neurology, Department of PediatricsVanderbilt University Medical Center Nashville Tennessee
| | - Spencer L. Waddle
- Department of Radiology and Radiological SciencesVanderbilt University Medical Center Nashville Tennessee
| | - Manus J. Donahue
- Department of NeurologyVanderbilt University Medical Center Nashville Tennessee
- Department of Radiology and Radiological SciencesVanderbilt University Medical Center Nashville Tennessee
- Department of Psychiatry and Behavioral SciencesVanderbilt University Medical Center Nashville Tennessee
- Department of Physics and AstronomyVanderbilt University Nashville Tennessee
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23
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Juttukonda MR, Donahue MJ, Davis LT, Gindville MC, Lee CA, Patel NJ, Kassim AA, Pruthi S, Hendrikse J, Jordan LC. Preliminary evidence for cerebral capillary shunting in adults with sickle cell anemia. J Cereb Blood Flow Metab 2019; 39:1099-1110. [PMID: 29260615 PMCID: PMC6547194 DOI: 10.1177/0271678x17746808] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Elevated flow velocities in adults with sickle cell anemia (SCA) may cause rapid erythrocyte transit through capillaries. This phenomenon could present as dural venous sinus hyperintensity on arterial spin labeling (ASL)-MRI and could be indicative of capillary shunting. Here, the prevalence of ASL venous hyperintensities and association with relevant physiology in adults with SCA was investigated. SCA ( n = 46) and age-matched control ( n = 16) volunteers were recruited for 3.0 T MRI. Pseudo-continuous ASL-MRI was acquired for cerebral blood flow (CBF) calculation and venous hyperintensity determination; venous signal intensity and a categorical venous score (three raters; 0 = no hyperintensity, 1 = focal hyperintensity, and 2 = diffuse hyperintensity) were recorded. Flow velocity in cervical internal carotid artery segments was determined from phase contrast data (venc = 40 cm/s) and whole-brain oxygen extraction fraction (OEF) was determined from T2-relaxation-under-spin-tagging MRI. Cerebral metabolic rate of oxygen was calculated as the product of OEF, CBF, and blood oxygen content. ASL venous hyperintensities were significantly ( p < 0.001) more prevalent in SCA (65%) relative to control (6%) participants and were associated with elevated flow velocities ( p = 0.03). CBF ( p < 0.001), but not OEF, increased with increasing hyperintensity score. Prospective trials that evaluate this construct as a possible marker of impaired oxygen delivery and stroke risk may be warranted.
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Affiliation(s)
- Meher R Juttukonda
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.,2 Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,3 Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA.,4 Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
| | - Larry T Davis
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Melissa C Gindville
- 5 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea A Lee
- 5 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J Patel
- 5 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adetola A Kassim
- 6 Department of Medicine, Division of Hematology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sumit Pruthi
- 1 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jeroen Hendrikse
- 7 Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Lori C Jordan
- 2 Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,5 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
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24
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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25
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Morris EA, Juttukonda MR, Lee CA, Patel NJ, Pruthi S, Donahue MJ, Jordan LC. Elevated brain oxygen extraction fraction in preterm newborns with anemia measured using noninvasive MRI. J Perinatol 2018; 38:1636-1643. [PMID: 30254332 DOI: 10.1038/s41372-018-0229-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/09/2018] [Accepted: 08/21/2018] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To test the hypothesis that cerebral oxygen extraction fraction (OEF) is elevated and inversely related to hematocrit level in anemic former very-low-birth-weight infants near term. STUDY DESIGN Prospective study of non-sedated preterm infants (post-menstrual age = 36 ± 2 weeks) over a range of hematocrits (0.23-0.49). Anatomical (T1-W, T2-W, and diffusion-weighted), cerebral blood flow (CBF), and OEF 3-T MRI were utilized. Statistical analysis included Spearman's rank-order correlation testing between study variables and intraclass correlation coefficients (ICC) calculated between consecutively acquired OEF scans. RESULTS Consecutive OEF measurements showed moderate-to-good agreement (ICC = 0.71; 95% CI = 0.40-0.87). OEF increased with worsening anemia (ρ = -0.58; p = 0.005), and OEF and basal ganglia CBF were positively correlated (ρ = 0.49; p = 0.023). CONCLUSION Noninvasive OEF MRI has moderate-to-good repeatability in non-sedated former preterm infants nearing term-equivalent age. Strong correlation of elevated OEF with anemia suggests hemodynamic compensation for anemia and could establish OEF as a useful biomarker of transfusion threshold for preterm infants.
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Affiliation(s)
- Emily A Morris
- Department of Pediatrics, Division of Neonatology, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chelsea A Lee
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niral J Patel
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sumit Pruthi
- 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
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
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26
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Juttukonda MR, Franco G, Englot DJ, Lin YC, Petersen KJ, Trujillo P, Hedera P, Landman BA, Kang H, Donahue MJ, Konrad PE, Dawant BM, Claassen DO. White matter differences between essential tremor and Parkinson disease. Neurology 2018; 92:e30-e39. [PMID: 30504432 DOI: 10.1212/wnl.0000000000006694] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/05/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To assess white matter integrity in patients with essential tremor (ET) and Parkinson disease (PD) with moderate to severe motor impairment. METHODS Sedated participants with ET (n = 57) or PD (n = 99) underwent diffusion tensor imaging (DTI) and fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity values were computed. White matter tracts were defined using 3 well-described atlases. To determine candidate white matter regions that differ between ET and PD groups, a bootstrapping analysis was applied using the least absolute shrinkage and selection operator. Linear regression was applied to assess magnitude and direction of differences in DTI metrics between ET and PD populations in the candidate regions. RESULTS Fractional anisotropy values that differentiate ET from PD localize primarily to thalamic and visual-related pathways, while diffusivity differences localized to the cerebellar peduncles. Patients with ET exhibited lower fractional anisotropy values than patients with PD in the lateral geniculate body (p < 0.01), sagittal stratum (p = 0.01), forceps major (p = 0.02), pontine crossing tract (p = 0.03), and retrolenticular internal capsule (p = 0.04). Patients with ET exhibited greater radial diffusivity values than patients with PD in the superior cerebellar peduncle (p < 0.01), middle cerebellar peduncle (p = 0.05), and inferior cerebellar peduncle (p = 0.05). CONCLUSIONS Regionally, distinctive white matter microstructural values in patients with ET localize to the cerebellar peduncles and thalamo-cortical visual pathways. These findings complement recent functional imaging studies in ET but also extend our understanding of putative physiologic features that account for distinctions between ET and PD.
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Affiliation(s)
- Meher R Juttukonda
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Giulia Franco
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Dario J Englot
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Ya-Chen Lin
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Kalen J Petersen
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Paula Trujillo
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Peter Hedera
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Bennett A Landman
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Hakmook Kang
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Manus J Donahue
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Peter E Konrad
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Benoit M Dawant
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Daniel O Claassen
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN.
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Juttukonda MR, Lee CA, Patel NJ, Davis LT, Waddle SL, Gindville MC, Pruthi S, Kassim AA, DeBaun MR, Donahue MJ, Jordan LC. Differential cerebral hemometabolic responses to blood transfusions in adults and children with sickle cell anemia. J Magn Reson Imaging 2018; 49:466-477. [PMID: 30324698 DOI: 10.1002/jmri.26213] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/18/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Blood transfusions are administered to children and adults with sickle cell anemia (SCA) for secondary stroke prevention, or as treatment for recurrent pain crises or acute anemia, but transfusion effects on cerebral hemodynamics and metabolism are not well-characterized. PURPOSE To compare blood transfusion-induced changes in hemometabolic parameters, including oxygen extraction fraction (OEF) and cerebral blood flow (CBF), within and between adults and children with SCA. STUDY TYPE Prospective, longitudinal study. SUBJECTS Adults with SCA (n = 16) receiving simple (n = 7) or exchange (n = 9) transfusions and children with SCA (n = 11) receiving exchange transfusions were scanned once when hematocrit was near nadir and again within 7 days of transfusion. Adult controls without SCA or sickle trait (n = 7) were scanned twice on separate days. FIELD STRENGTH/SEQUENCE 3.0T T1 -weighted, T2 -weighted, and T2 -relaxation-under-spin-tagging (TRUST) imaging, and phase contrast angiography. ASSESSMENT Global OEF was computed as the relative difference between venous oxygenation (from TRUST) and arterial oxygenation (from pulse oximetry). Global CBF was computed as total blood flow to the brain normalized by intracranial tissue volume. STATISTICAL TESTS Hemometabolic variables were compared using two-sided Wilcoxon signed-rank tests; associations were analyzed using two-sided Spearman's correlation testing. RESULTS In adults with SCA, posttransfusion OEF = 0.38 ± 0.05 was lower (P = 0.001) than pretransfusion OEF = 0.45 ± 0.09. A change in OEF was correlated with increases in hematocrit (P = 0.02; rho = -0.62) and with pretransfusion hematocrit (P = 0.02; rho = 0.65). OEF changes after transfusion were greater (P = 0.002) in adults receiving simple versus exchange transfusions. Posttransfusion CBF = 77.7 ± 26.4 ml/100g/min was not different (P = 0.27) from pretransfusion CBF = 82.3 ± 30.2 ml/100g/min. In children with SCA, both posttransfusion OEF = 0.28 ± 0.04 and CBF = 76.4 ± 26.4 were lower than pretransfusion OEF = 0.36 ± 0.06 (P = 0.004) and CBF = 96.4 ± 16.5 (P = 0.004). DATA CONCLUSION Cerebral OEF reduces following transfusions in adults and children with SCA. CBF reduces following transfusions more often in children compared to adults, indicating that vascular reserve capacity may remain near exhaustion posttransfusion in many adults. LEVEL OF EVIDENCE 2 Technical Efficacy Stage 5 J. Magn. Reson. Imaging 2019;49:466-477.
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Affiliation(s)
- Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Chelsea A Lee
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Niral J Patel
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Larry T Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Spencer L Waddle
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Melissa C Gindville
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sumit Pruthi
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Adetola A Kassim
- Department of Medicine, Division of Hematology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Michael R DeBaun
- Department of Pediatrics, Division of Hematology/Oncology, 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 Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Psychiatry, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee, USA
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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28
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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29
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Petersen KJ, Reid JA, Chakravorti S, Juttukonda MR, Franco G, Trujillo P, Stark AJ, Dawant BM, Donahue MJ, Claassen DO. Structural and functional connectivity of the nondecussating dentato-rubro-thalamic tract. Neuroimage 2018; 176:364-371. [PMID: 29733955 PMCID: PMC6002752 DOI: 10.1016/j.neuroimage.2018.04.074] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 04/04/2018] [Accepted: 04/30/2018] [Indexed: 12/20/2022] Open
Abstract
The dentato-rubro-thalamic tract (DRTT) regulates motor control, connecting the cerebellum to the thalamus. This tract is modulated by deep-brain stimulation in the surgical treatment of medically refractory tremor, especially in essential tremor, where high-frequency stimulation of the thalamus can improve symptoms. The DRTT is classically described as a decussating pathway, ascending to the contralateral thalamus. However, the existence of a nondecussating (i.e. ipsilateral) DRTT in humans was recently demonstrated, and these tracts are arranged in distinct regions of the superior cerebellar peduncle. We hypothesized that the ipsilateral DRTT is connected to specific thalamic nuclei and therefore may have unique functional relevance. The goals of this study were to confirm the presence of the decussating and nondecussating DRTT pathways, identify thalamic termination zones of each tract, and compare whether structural connectivity findings agree with functional connectivity. Diffusion-weighted imaging was used to perform probabilistic tractography of the decussating and nondecussating DRTT in young healthy subjects from the Human Connectome Project (n = 91) scanned using multi-shell diffusion-weighted imaging (270 directions; TR/TE = 5500/89 ms; spatial resolution = 1.25 mm isotropic). To define thalamic anatomical landmarks, a segmentation procedure based on the Morel Atlas was employed, and DRTT targeting was quantified based on the proportion of streamlines arriving at each nucleus. In parallel, functional connectivity analysis was performed using resting-state functional MRI (TR/TE = 720/33 ms; spatial resolution = 2 mm isotropic). It was found that the decussating and nondecussating DRTTs have significantly different thalamic endpoints, with the former preferentially targeting relatively anterior and lateral thalamic nuclei, and the latter connected to more posterior and medial nuclei (p < 0.001). Functional and structural connectivity measures were found to be significantly correlated (r = 0.45, p = 0.031). These findings provide new insight into pathways through which unilateral cerebellum can exert bilateral influence on movement and raise questions about the functional implications of ipsilateral cerebellar efferents.
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Affiliation(s)
- Kalen J Petersen
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | | | - Srijata Chakravorti
- Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, USA
| | - Meher R Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Giulia Franco
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Paula Trujillo
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adam J Stark
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Benoit M Dawant
- Department of Electrical Engineering and Computer Science, Vanderbilt University, 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
| | - Daniel O Claassen
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.
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30
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Jordan LC, Kassim AA, Donahue MJ, Juttukonda MR, Pruthi S, Davis LT, Rodeghier M, Lee CA, Patel NJ, DeBaun MR. Silent infarct is a risk factor for infarct recurrence in adults with sickle cell anemia. Neurology 2018; 91:e781-e784. [PMID: 30054441 DOI: 10.1212/wnl.0000000000006047] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/18/2018] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Because of the high prevalence of silent cerebral infarcts (SCIs) in adults with sickle cell anemia (SCA) and lack of information to guide treatment strategies, we evaluated the risk of recurrent SCIs and overt stroke in adults with SCA with preexisting SCI. METHODS This observational study included adults with SCA (HbSS or Sβ0 thalassemia) aged 18 to 40 years. Participants received 3-tesla brain MRI and a detailed neurologic examination. Time-to-event analysis assessed those with or without baseline SCI and with new or progressive infarcts. The incidence rate of new events was compared by log-rank test. Univariable Cox regression assessed the association of SCI with infarct progression. RESULTS Among adults with SCA with 2 MRIs and at least 6 months between MRIs (n = 54, mean interval = 2.5 years), 43% had SCI at baseline. Of participants with baseline SCI, 30% had new or progressive SCI over 2.5 years compared to 6% with no SCI at baseline; no participant had an overt stroke. New SCIs at follow-up were present in 12.9 per 100 patient-years with existing SCI compared with 2.4 per 100 patient-years without prior SCI (log-rank test, p = 0.021). No statistically significant differences were seen among those with or without baseline SCI in use of hydroxyurea therapy, hydroxyurea dose, or other stroke risk factors. The presence of SCI was associated with increased hazard of a new or progressive infarct (hazard ratio 5.27, 95% confidence interval 1.09-25.51, p = 0.039). CONCLUSIONS Silent infarcts in adults with SCA are common and are a significant risk factor for future silent infarcts.
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Affiliation(s)
- Lori C Jordan
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL.
| | - Adetola A Kassim
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Manus J Donahue
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Meher R Juttukonda
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Sumit Pruthi
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Larry T Davis
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Mark Rodeghier
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Chelsea A Lee
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Niral J Patel
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
| | - Michael R DeBaun
- From the Department of Pediatrics, Division of Pediatric Neurology (L.C.J., C.A.L., N.J.P.), Vanderbilt-Meharry Sickle Cell Center for Excellence (A.A.K., M.R.D.), Departments of Radiology and Radiological Sciences (M.J.D., M.R.J.), Neurology (M.J.D.), and Psychiatry (M.J.D.), and Department of Radiology, Divisions of Pediatric Radiology and Neuroradiology (S.P.), and Department of Radiology, Division of Neuroradiology (L.T.D.), Vanderbilt University Medical Center, Nashville; Department of Physics and Astronomy (M.J.D.), Vanderbilt University, Nashville, TN; and Rodeghier Consultants (M.R.), Chicago, IL
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Juttukonda MR, Jordan LC, Gindville MC, Davis LT, Watchmaker JM, Pruthi S, Donahue MJ. Cerebral hemodynamics and pseudo-continuous arterial spin labeling considerations in adults with sickle cell anemia. NMR Biomed 2017; 30:10.1002/nbm.3681. [PMID: 28052565 PMCID: PMC5351809 DOI: 10.1002/nbm.3681] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 10/11/2016] [Accepted: 11/12/2016] [Indexed: 05/28/2023]
Abstract
Sickle cell anemia (SCA) is a genetic disorder resulting in reduced oxygen carrying capacity and elevated stroke risk. Pseudo-continuous arterial spin labeling (pCASL) measures of cerebral blood flow (CBF) may have relevance for stroke risk assessment; however, the effects of elevated flow velocity and reduced bolus arrival time (BAT) on CBF quantification in SCA patients have not been thoroughly characterized, and pCASL model parameters used in healthy adults are often applied to patients with SCA. Here, cervical arterial flow velocities and pCASL labeling efficiencies were computed in adults with SCA (n = 19) and age- and race-matched controls without sickle trait (n = 7) using pCASL in sequence with phase contrast MR angiography (MRA). Controls (n = 7) and a subgroup of patients (n = 8) also underwent multi-post-labeling-delay pCASL for BAT assessment. Mean flow velocities were elevated in SCA adults (velocity = 28.3 ± 4.1 cm/s) compared with controls (velocity = 24.5 ± 3.8 cm/s), and mean pCASL labeling efficiency (α) was reduced in SCA adults (α = 0.72) relative to controls (α = 0.91). In patients, mean whole-brain CBF from phase contrast MRA was 91.8 ± 18.1 ml/100 g/min, while mean pCASL CBF when assuming a constant labeling efficiency of 0.86 was 75.2 ± 17.3 ml/100 g/min (p < 0.01), resulting in a mean absolute quantification error of 23% when a labeling efficiency appropriate for controls was assumed. This difference cannot be accounted for by BAT (whole-brain BAT: control, 1.13 ± 0.06 s; SCA, 1.02 ± 0.09 s) or tissue T1 variation. In conclusion, BAT variation influences pCASL quantification less than elevated cervical arterial velocity and labeling efficiency variation in SCA adults; thus, a lower labeling efficiency (α = 0.72) or subject-specific labeling efficiency should be incorporated for SCA patients.
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Affiliation(s)
- Meher R. Juttukonda
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee USA
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee USA
| | - Lori C. Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt Medical Center, Nashville, Tennessee USA
| | - Melissa C. Gindville
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt Medical Center, Nashville, Tennessee USA
| | - Larry T. Davis
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee USA
| | | | - Sumit Pruthi
- 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
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee USA
- Department of Psychiatry, Vanderbilt University Medical Center, Nashville, Tennessee USA
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Juttukonda MR, Donahue MJ, Gindville MC, Pruthi S, Kassim AA, Watchmaker JM, Hendrikse J, Jordan LC. Abstract 109: Non-invasive Detection of Capillary Arteriovenous Shunting in Patients With Sickle Cell Anemia. Stroke 2017. [DOI: 10.1161/str.48.suppl_1.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
High blood velocity can cause rapid erythrocyte transit through capillaries, reducing efficiency of oxygen delivery to tissue (capillary arteriovenous shunting). Arterial spin labeling (ASL) is an MRI technique that utilizes magnetic labeling of arterial blood water for CBF quantitation. Labeled water that traverses capillaries without exchanging with tissue leads to hyperintense venous signal indicative of arteriovenous shunting. We hypothesized that venous hyperintensity is present in sickle cell anemia (SCA) adults, correlates with flow velocity, and corresponds with clinical impairment and oxygen extraction fraction (OEF).
Methods:
ASL for shunting determination, TRUST for OEF measurement, phase contrast angiography for velocity assessment, and FLAIR / MRA for infarct / vasculopathy evaluation were performed at 3T in adults with SCA (n=36) and age- and race-matched controls (n=11). Three reviewers assessed for hyperintensity in the superior sagittal sinus on ASL images (Fig) and assigned scores of 0 (none), 1 (mild, focal), 2 (significant, focal), or 3 (significant, diffuse). Shunting scores were compared with the presence of clinical impairment (prior infarcts, stenosis>50%, or severe disease requiring transfusions) and OEF.
Results:
Interobserver agreement was excellent (Fleiss’ κ=0.91). Consensus shunting score in SCA adults (1.2±1.1) was higher (p<0.01) than controls (0.1±0.3), Median age 27.6 y, 57% F. Elevated shunting scores were observed in SCA adults with (1.23±1.07) vs. without (1.07±1.16) clinical impairment. A trend (p=0.068) for elevated OEF was observed in those with shunting scores ≥2 (0.44±0.07) vs. those with shunting scores ≤1 (0.40±0.07). Cervical flow velocity was elevated in subjects with shunting scores ≥2 (30.2±4.8 cm/s) vs. ≤1 (25.3±4.8 cm/s).
Conclusion:
Venous hyperintensity in ASL images may indicate capillary arteriovenous shunting and may reflect higher clinical impairment and elevated OEF.
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Affiliation(s)
| | | | | | - Sumit Pruthi
- Radiology, Vanderbilt Univ Med Cntr, Nashville, TN
| | - Adetola A Kassim
- Internal Medicine, Div of Hematology, Vanderbilt Univ Med Cntr, Nashville, TN
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Jordan LC, Gindville MC, Scott AO, Juttukonda MR, Strother MK, Kassim AA, Chen SC, Lu H, Pruthi S, Shyr Y, Donahue MJ. Non-invasive imaging of oxygen extraction fraction in adults with sickle cell anaemia. Brain 2016; 139:738-50. [PMID: 26823369 DOI: 10.1093/brain/awv397] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/30/2015] [Indexed: 11/12/2022] Open
Abstract
Sickle cell anaemia is a monogenetic disorder with a high incidence of stroke. While stroke screening procedures exist for children with sickle cell anaemia, no accepted screening procedures exist for assessing stroke risk in adults. The purpose of this study is to use novel magnetic resonance imaging methods to evaluate physiological relationships between oxygen extraction fraction, cerebral blood flow, and clinical markers of cerebrovascular impairment in adults with sickle cell anaemia. The specific goal is to determine to what extent elevated oxygen extraction fraction may be uniquely present in patients with higher levels of clinical impairment and therefore may represent a candidate biomarker of stroke risk. Neurological evaluation, structural imaging, and the non-invasive T2-relaxation-under-spin-tagging magnetic resonance imaging method were applied in sickle cell anaemia (n = 34) and healthy race-matched control (n = 11) volunteers without sickle cell trait to assess whole-brain oxygen extraction fraction, cerebral blood flow, degree of vasculopathy, severity of anaemia, and presence of prior infarct; findings were interpreted in the context of physiological models. Cerebral blood flow and oxygen extraction fraction were elevated (P < 0.05) in participants with sickle cell anaemia (n = 27) not receiving monthly blood transfusions (interquartile range cerebral blood flow = 46.2-56.8 ml/100 g/min; oxygen extraction fraction = 0.39-0.50) relative to controls (interquartile range cerebral blood flow = 40.8-46.3 ml/100 g/min; oxygen extraction fraction = 0.33-0.38). Oxygen extraction fraction (P < 0.0001) but not cerebral blood flow was increased in participants with higher levels of clinical impairment. These data provide support for T2-relaxation-under-spin-tagging being able to quickly and non-invasively detect elevated oxygen extraction fraction in individuals with sickle cell anaemia with higher levels of clinical impairment. Our results support the premise that magnetic resonance imaging-based assessment of elevated oxygen extraction fraction might be a viable screening tool for evaluating stroke risk in adults with sickle cell anaemia.
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Affiliation(s)
- Lori C Jordan
- 1 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Melissa C Gindville
- 1 Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Allison O Scott
- 2 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Meher R Juttukonda
- 2 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Megan K Strother
- 2 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adetola A Kassim
- 3 Vanderbilt-Meharry Center of Excellence in Sickle Cell Disease, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sheau-Chiann Chen
- 4 Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Hanzhang Lu
- 5 Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sumit Pruthi
- 2 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yu Shyr
- 4 Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- 2 Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA 6 Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA 7 Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
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Juttukonda MR, Mersereau BG, Chen Y, Su Y, Rubin BG, Benzinger TLS, Lalush DS, An H. MR-based attenuation correction for PET/MRI neurological studies with continuous-valued attenuation coefficients for bone through a conversion from R2* to CT-Hounsfield units. Neuroimage 2015; 112:160-168. [PMID: 25776213 DOI: 10.1016/j.neuroimage.2015.03.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/04/2015] [Accepted: 03/06/2015] [Indexed: 01/01/2023] Open
Abstract
AIM MR-based correction for photon attenuation in PET/MRI remains challenging, particularly for neurological applications requiring quantitation of data. Existing methods are either not sufficiently accurate or are limited by the computation time required. The goal of this study was to develop an MR-based attenuation correction method that accurately separates bone tissue from air and provides continuous-valued attenuation coefficients for bone. MATERIALS AND METHODS PET/MRI and CT datasets were obtained from 98 subjects (mean age [±SD]: 66yrs [±9.8], 57 females) using an IRB-approved protocol and with informed consent. Subjects were injected with 352±29MBq of (18)F-Florbetapir tracer, and PET acquisitions were begun either immediately or 50min after injection. CT images of the head were acquired separately using a PET/CT system. Dual echo ultrashort echo-time (UTE) images and two-point Dixon images were acquired. Regions of air were segmented via a threshold of the voxel-wise multiplicative inverse of the UTE echo 1 image. Regions of bone were segmented via a threshold of the R2* image computed from the UTE echo 1 and UTE echo 2 images. Regions of fat and soft tissue were segmented using fat and water images decomposed from the Dixon images. Air, fat, and soft tissue were assigned linear attenuation coefficients (LACs) of 0, 0.092, and 0.1cm(-1), respectively. LACs for bone were derived from a regression analysis between corresponding R2* and CT values. PET images were reconstructed using the gold standard CT method and the proposed CAR-RiDR method. RESULTS The RiDR segmentation method produces mean Dice coefficient±SD across subjects of 0.75±0.05 for bone and 0.60±0.08 for air. The CAR model for bone LACs greatly improves accuracy in estimating CT values (28.2%±3.0 mean error) compared to the use of a constant CT value (46.9%±5.8, p<10(-6)). Finally, the CAR-RiDR method provides a low whole-brain mean absolute percent-error (MAPE±SD) in PET reconstructions across subjects of 2.55%±0.86. Regional PET errors were also low and ranged from 0.88% to 3.79% in 24 brain ROIs. CONCLUSION We propose an MR-based attenuation correction method (CAR-RiDR) for quantitative PET neurological imaging. The proposed method employs UTE and Dixon images and consists of two novel components: 1) accurate segmentation of air and bone using the inverse of the UTE1 image and the R2* image, respectively and 2) estimation of continuous LAC values for bone using a regression between R2* and CT-Hounsfield units. From our analysis, we conclude that the proposed method closely approaches (<3% error) the gold standard CT-scaled method in PET reconstruction accuracy.
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Affiliation(s)
- Meher R Juttukonda
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC 27599, USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Bryant G Mersereau
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC 27599, USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Yasheng Chen
- Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Yi Su
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63130, USA
| | - Brian G Rubin
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63130, USA
| | - Tammie L S Benzinger
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63130, USA; Department of Neurological Surgery, Washington University, St. Louis, MO 63130, USA
| | - David S Lalush
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC 27599, USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Hongyu An
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC 27599, USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Radiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Dortch RD, Harkins KD, Juttukonda MR, Gore JC, Does MD. Characterizing inter-compartmental water exchange in myelinated tissue using relaxation exchange spectroscopy. Magn Reson Med 2012; 70:1450-9. [PMID: 23233414 DOI: 10.1002/mrm.24571] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 10/16/2012] [Accepted: 10/30/2012] [Indexed: 12/20/2022]
Abstract
PURPOSE To investigate inter-compartmental water exchange in two model myelinated tissues ex vivo using relaxation exchange spectroscopy. METHODS Building upon a previously developed theoretical framework, a three-compartment (myelin, intra-axonal, and extra-axonal water) model of the inversion-recovery prepared relaxation exchange spectroscopy signal was applied in excised rat optic nerve and frog sciatic nerve samples to estimate the water residence time constants in myelin (τmyelin ). RESULTS In the rat optic nerve samples, τmyelin = 138 ± 15 ms (mean ± standard deviation) was estimated. In sciatic nerve, which possesses thicker myelin sheaths than optic nerve, a much longer τmyelin = 2046 ± 140 ms was observed. CONCLUSION Consistent with previous studies in rat spinal cord, the extrapolation of exchange rates in optic nerve to in vivo conditions indicates that τmyelin < 100 ms. This suggests that there is a significant effect of inter-compartmental water exchange on the transverse relaxation of water protons in white matter. The much longer τmyelin values in sciatic nerve supports the postulate that the inter-compartmental water exchange rate is mediated by myelin thickness. Together, these findings point to the potential for MRI methods to probe variations in myelin thickness in white matter.
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Affiliation(s)
- Richard D Dortch
- Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, USA
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