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Shalom ES, Kim H, van der Heijden RA, Ahmed Z, Patel R, Hormuth DA, DiCarlo JC, Yankeelov TE, Sisco NJ, Dortch RD, Stokes AM, Inglese M, Grech-Sollars M, Toschi N, Sahoo P, Singh A, Verma SK, Rathore DK, Kazerouni AS, Partridge SC, LoCastro E, Paudyal R, Wolansky IA, Shukla-Dave A, Schouten P, Gurney-Champion OJ, Jiřík R, Macíček O, Bartoš M, Vitouš J, Das AB, Kim SG, Bokacheva L, Mikheev A, Rusinek H, Berks M, Hubbard Cristinacce PL, Little RA, Cheung S, O'Connor JPB, Parker GJM, Moloney B, LaViolette PS, Bobholz S, Duenweg S, Virostko J, Laue HO, Sung K, Nabavizadeh A, Saligheh Rad H, Hu LS, Sourbron S, Bell LC, Fathi Kazerooni A. The ISMRM Open Science Initiative for Perfusion Imaging (OSIPI): Results from the OSIPI-Dynamic Contrast-Enhanced challenge. Magn Reson Med 2024; 91:1803-1821. [PMID: 38115695 DOI: 10.1002/mrm.29909] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 08/22/2023] [Accepted: 10/16/2023] [Indexed: 12/21/2023]
Abstract
PURPOSE K trans $$ {K}^{\mathrm{trans}} $$ has often been proposed as a quantitative imaging biomarker for diagnosis, prognosis, and treatment response assessment for various tumors. None of the many software tools forK trans $$ {K}^{\mathrm{trans}} $$ quantification are standardized. The ISMRM Open Science Initiative for Perfusion Imaging-Dynamic Contrast-Enhanced (OSIPI-DCE) challenge was designed to benchmark methods to better help the efforts to standardizeK trans $$ {K}^{\mathrm{trans}} $$ measurement. METHODS A framework was created to evaluateK trans $$ {K}^{\mathrm{trans}} $$ values produced by DCE-MRI analysis pipelines to enable benchmarking. The perfusion MRI community was invited to apply their pipelines forK trans $$ {K}^{\mathrm{trans}} $$ quantification in glioblastoma from clinical and synthetic patients. Submissions were required to include the entrants'K trans $$ {K}^{\mathrm{trans}} $$ values, the applied software, and a standard operating procedure. These were evaluated using the proposedOSIP I gold $$ \mathrm{OSIP}{\mathrm{I}}_{\mathrm{gold}} $$ score defined with accuracy, repeatability, and reproducibility components. RESULTS Across the 10 received submissions, theOSIP I gold $$ \mathrm{OSIP}{\mathrm{I}}_{\mathrm{gold}} $$ score ranged from 28% to 78% with a 59% median. The accuracy, repeatability, and reproducibility scores ranged from 0.54 to 0.92, 0.64 to 0.86, and 0.65 to 1.00, respectively (0-1 = lowest-highest). Manual arterial input function selection markedly affected the reproducibility and showed greater variability inK trans $$ {K}^{\mathrm{trans}} $$ analysis than automated methods. Furthermore, provision of a detailed standard operating procedure was critical for higher reproducibility. CONCLUSIONS This study reports results from the OSIPI-DCE challenge and highlights the high inter-software variability withinK trans $$ {K}^{\mathrm{trans}} $$ estimation, providing a framework for ongoing benchmarking against the scores presented. Through this challenge, the participating teams were ranked based on the performance of their software tools in the particular setting of this challenge. In a real-world clinical setting, many of these tools may perform differently with different benchmarking methodology.
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Affiliation(s)
- Eve S Shalom
- School of Physics and Astronomy, University of Leeds, Leeds, UK
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Harrison Kim
- Department of Radiology, University of Alabama, Birmingham, Alabama, USA
| | - Rianne A van der Heijden
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Zaki Ahmed
- Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, USA
| | - Reyna Patel
- Department of Radiology, Neuroradiology Division, Mayo Clinic, Scottsdale, Arizona, USA
| | - David A Hormuth
- Oden Institute for Computational Engineering and Sciences, The University of Texas, Austin, Texas, USA
| | - Julie C DiCarlo
- Biomedical Imaging Center, Livestrong Cancer Institutes, University of Texas at Austin, Austin, Texas, USA
| | - Thomas E Yankeelov
- Departments of Biomedical Engineering, Diagnostic Medicine, Oncology, Livestrong Cancer Institutes, Oden Institute for Computational Engineering and Sciences, The University of Texas, Austin, Texas, USA
- Department of Imaging Physics, MD Anderson Cancer Center, Houston, Texas, USA
| | - Nicholas J Sisco
- Department of Translational Neuroscience, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Richard D Dortch
- Department of Translational Neuroscience, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Ashley M Stokes
- Department of Translational Neuroscience, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Marianna Inglese
- Department of Biomedicine and Prevention, University of Rome, Tor Vergata, Italy
- Department of Surgery and Cancer, Imperial College, London, UK
| | - Matthew Grech-Sollars
- Department of Surgery and Cancer, Imperial College, London, UK
- Department of Computer Science, University College London, London, UK
- Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Nicola Toschi
- Department of Biomedicine and Prevention, University of Rome, Tor Vergata, Italy
- Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Boston, Massachusetts, USA
| | - Prativa Sahoo
- University Medical Center Göttingen, Göttingen, Germany
| | - Anup Singh
- Center for Biomedical Engineering, Indian Institute of Technology Delhi, New Delhi, India
| | - Sanjay K Verma
- Institute of Bioengineering and Bioimaging, Singapore, Singapore
| | - Divya K Rathore
- Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
| | - Anum S Kazerouni
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | | | - Eve LoCastro
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ramesh Paudyal
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ivan A Wolansky
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Amita Shukla-Dave
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Pepijn Schouten
- Department of Radiology and Nuclear Medicine, University of Amsterdam, Amsterdam, The Netherlands
| | - Oliver J Gurney-Champion
- Department of Radiology and Nuclear Medicine, University of Amsterdam, Amsterdam, The Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Radovan Jiřík
- Czech Academy of Sciences, Institute of Scientific Instruments, Brno, Czech Republic
| | - Ondřej Macíček
- Czech Academy of Sciences, Institute of Scientific Instruments, Brno, Czech Republic
| | - Michal Bartoš
- Czech Academy of Sciences, Institute of Information Theory and Automation, Praha, Czech Republic
| | - Jiří Vitouš
- Czech Academy of Sciences, Institute of Scientific Instruments, Brno, Czech Republic
| | | | - S Gene Kim
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Louisa Bokacheva
- Department of Radiology, Grossman School of Medicine, New York University, New York, New York, USA
| | - Artem Mikheev
- Department of Radiology, Grossman School of Medicine, New York University, New York, New York, USA
| | - Henry Rusinek
- Department of Radiology, Grossman School of Medicine, New York University, New York, New York, USA
| | - Michael Berks
- Division of Cancer Sciences, University of Manchester, Manchester, UK
| | | | - Ross A Little
- Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Susan Cheung
- Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - James P B O'Connor
- Division of Cancer Sciences, University of Manchester, Manchester, UK
- Department of Radiology, The Christie Hospital NHS Trust, Manchester, UK
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, UK
| | - Geoff J M Parker
- Center for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, UK
- Bioxydyn Ltd, Manchester, UK
| | - Brendan Moloney
- Advanced Imaging Research Center, Oregon Health & Science Institute, Portland, Oregon, USA
| | - Peter S LaViolette
- Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Samuel Bobholz
- Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Savannah Duenweg
- Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John Virostko
- Department of Diagnostic Medicine, University of Texas, Austin, Texas, USA
| | - Hendrik O Laue
- Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
| | - Kyunghyun Sung
- Department of Radiological Sciences, University of California, Los Angeles, California, USA
| | - Ali Nabavizadeh
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Data-Driven Discovery, Division of Neurosurgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Hamidreza Saligheh Rad
- Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran
- Center for Computational Imaging & Simulation Technologies in Biomedicine, School of Computing/School of Medicine, University of Leeds, Leeds, UK
| | - Leland S Hu
- Neuroradiology Division, Department of Radiology, Mayo Clinic, Phoenix, Arizona, USA
| | - Steven Sourbron
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Laura C Bell
- Clinical Imaging Group, Genentech, Inc., South San Francisco, California, USA
| | - Anahita Fathi Kazerooni
- Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Pennsylvania, USA
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Bell LC, Suzuki Y, van Houdt PJ, Sourbron S, Mutsaerts HJMM. The road to the ISMRM OSIPI: A community-led initiative for reproducible perfusion MRI. Magn Reson Med 2024; 91:1740-1742. [PMID: 37279059 DOI: 10.1002/mrm.29736] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 06/07/2023]
Affiliation(s)
- Laura C Bell
- Genentech, Inc., Clinical Imaging Group, South San Francisco, California, USA
| | - Yuriko Suzuki
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Petra J van Houdt
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Steven Sourbron
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Henk J M M Mutsaerts
- Department of Radiology and Nuclear Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Brain Imaging, Amsterdam, The Netherlands
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Dickie BR, Ahmed Z, Arvidsson J, Bell LC, Buckley DL, Debus C, Fedorov A, Floca R, Gutmann I, van der Heijden RA, van Houdt PJ, Sourbron S, Thrippleton MJ, Quarles C, Kompan IN. A community-endorsed open-source lexicon for contrast agent-based perfusion MRI: A consensus guidelines report from the ISMRM Open Science Initiative for Perfusion Imaging (OSIPI). Magn Reson Med 2024; 91:1761-1773. [PMID: 37831600 DOI: 10.1002/mrm.29840] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/25/2023] [Accepted: 08/04/2023] [Indexed: 10/15/2023]
Abstract
This manuscript describes the ISMRM OSIPI (Open Science Initiative for Perfusion Imaging) lexicon for dynamic contrast-enhanced and dynamic susceptibility-contrast MRI. The lexicon was developed by Taskforce 4.2 of OSIPI to provide standardized definitions of commonly used quantities, models, and analysis processes with the aim of reducing reporting variability. The taskforce was established in February 2020 and consists of medical physicists, engineers, clinicians, data and computer scientists, and DICOM (Digital Imaging and Communications in Medicine) standard experts. Members of the taskforce collaborated via a slack channel and quarterly virtual meetings. Members participated by defining lexicon items and reporting formats that were reviewed by at least two other members of the taskforce. Version 1.0.0 of the lexicon was subject to open review from the wider perfusion imaging community between January and March 2022, and endorsed by the Perfusion Study Group of the ISMRM in the summer of 2022. The initial scope of the lexicon was set by the taskforce and defined such that it contained a basic set of quantities, processes, and models to enable users to report an end-to-end analysis pipeline including kinetic model fitting. We also provide guidance on how to easily incorporate lexicon items and definitions into free-text descriptions (e.g., in manuscripts and other documentation) and introduce an XML-based pipeline encoding format to encode analyses using lexicon definitions in standardized and extensible machine-readable code. The lexicon is designed to be open-source and extendable, enabling ongoing expansion of its content. We hope that widespread adoption of lexicon terminology and reporting formats described herein will increase reproducibility within the field.
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Affiliation(s)
- Ben R Dickie
- Division of Informatics, Imaging, and Data Sciences, School of Health Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
- Geoffrey Jefferson Brain Research Center, Manchester Academic Health Science Center, The University of Manchester, Manchester, UK
| | - Zaki Ahmed
- Corewell Health William Beaumont University Hospital, Royal Oak, Michigan, USA
| | - Jonathan Arvidsson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Laura C Bell
- Clinical Imaging Group, Genentech, Inc., South San Francisco, California, USA
| | | | | | - Andrey Fedorov
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ralf Floca
- National Center for Radiation Research in Oncology, Heidelberg Institute for Radiation Oncology, Heidelberg, Germany
| | - Ingomar Gutmann
- Faculty of Physics, Physics of Functional Materials, University of Vienna, Vienna, Austria
| | - Rianne A van der Heijden
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Petra J van Houdt
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Steven Sourbron
- Department of Infection, Immunity, and Cardiovascular Diseases, University of Sheffield, Sheffield, UK
| | - Michael J Thrippleton
- Edinburgh Imaging and Center for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Chad Quarles
- Department of Cancer Systems Imaging, UT MD Anderson Cancer Center, Houston, Texas, USA
| | - Ina N Kompan
- Division of Medical Image Computing, German Cancer Research Center, Heidelberg, Germany
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Bell LC, Shimron E. Sharing Data Is Essential for the Future of AI in Medical Imaging. Radiol Artif Intell 2024; 6:e230337. [PMID: 38231036 PMCID: PMC10831510 DOI: 10.1148/ryai.230337] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/16/2023] [Accepted: 11/20/2023] [Indexed: 01/18/2024]
Abstract
If we want artificial intelligence to succeed in radiology, we must share data and learn how to share data.
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Affiliation(s)
- Laura C. Bell
- From the Clinical Imaging Group, Genentech, 1 DNA Way, South San
Francisco, CA 94080 (L.C.B.); and Department of Electrical and Computer
Engineering and Department of Biomedical Engineering, Technion-Israel Institute
of Technology, Haifa, Israel (E.S.)
| | - Efrat Shimron
- From the Clinical Imaging Group, Genentech, 1 DNA Way, South San
Francisco, CA 94080 (L.C.B.); and Department of Electrical and Computer
Engineering and Department of Biomedical Engineering, Technion-Israel Institute
of Technology, Haifa, Israel (E.S.)
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5
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Anil A, Stokes AM, Chao R, Hu LS, Alhilali L, Karis JP, Bell LC, Quarles CC. Identification of single-dose, dual-echo based CBV threshold for fractional tumor burden mapping in recurrent glioblastoma. Front Oncol 2023; 13:1046629. [PMID: 36733305 PMCID: PMC9887158 DOI: 10.3389/fonc.2023.1046629] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 01/03/2023] [Indexed: 01/18/2023] Open
Abstract
Background Relative cerebral blood volume (rCBV) obtained from dynamic susceptibility contrast (DSC) MRI is widely used to distinguish high grade glioma recurrence from post treatment radiation effects (PTRE). Application of rCBV thresholds yield maps to distinguish between regional tumor burden and PTRE, a biomarker termed the fractional tumor burden (FTB). FTB is generally measured using conventional double-dose, single-echo DSC-MRI protocols; recently, a single-dose, dual-echo DSC-MRI protocol was clinically validated by direct comparison to the conventional double-dose, single-echo protocol. As the single-dose, dual-echo acquisition enables reduction in the contrast agent dose and provides greater pulse sequence parameter flexibility, there is a compelling need to establish dual-echo DSC-MRI based FTB mapping. In this study, we determine the optimum standardized rCBV threshold for the single-dose, dual-echo protocol to generate FTB maps that best match those derived from the reference standard, double-dose, single-echo protocol. Methods The study consisted of 23 high grade glioma patients undergoing perfusion scans to confirm suspected tumor recurrence. We sequentially acquired single dose, dual-echo and double dose, single-echo DSC-MRI data. For both protocols, we generated leakage-corrected standardized rCBV maps. Standardized rCBV (sRCBV) thresholds of 1.0 and 1.75 were used to compute single-echo FTB maps as the reference for delineating PTRE (sRCBV < 1.0), tumor with moderate angiogenesis (1.0 < sRCBV < 1.75), and tumor with high angiogenesis (sRCBV > 1.75) regions. To assess the sRCBV agreement between acquisition protocols, the concordance correlation coefficient (CCC) was computed between the mean tumor sRCBV values across the patients. A receiver operating characteristics (ROC) analysis was performed to determine the optimum dual-echo sRCBV threshold. The sensitivity, specificity, and accuracy were compared between the obtained optimized threshold (1.64) and the standard reference threshold (1.75) for the dual-echo sRCBV threshold. Results The mean tumor sRCBV values across the patients showed a strong correlation (CCC = 0.96) between the two protocols. The ROC analysis showed maximum accuracy at thresholds of 1.0 (delineate PTRE from tumor) and 1.64 (differentiate aggressive tumors). The reference threshold (1.75) and the obtained optimized threshold (1.64) yielded similar accuracy, with slight differences in sensitivity and specificity which were not statistically significant (1.75 threshold: Sensitivity = 81.94%; Specificity: 87.23%; Accuracy: 84.58% and 1.64 threshold: Sensitivity = 84.48%; Specificity: 84.97%; Accuracy: 84.73%). Conclusions The optimal sRCBV threshold for single-dose, dual-echo protocol was found to be 1.0 and 1.64 for distinguishing tumor recurrence from PTRE; however, minimal differences were observed when using the standard threshold (1.75) as the upper threshold, suggesting that the standard threshold could be used for both protocols. While the prior study validated the agreement of the mean sRCBV values between the protocols, this study confirmed that their voxel-wise agreement is suitable for reliable FTB mapping. Dual-echo DSC-MRI acquisitions enable robust single-dose sRCBV and FTB mapping, provide pulse sequence parameter flexibility and should improve reproducibility by mitigating variations in preload dose and incubation time.
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Affiliation(s)
- Aliya Anil
- Division of Neuroimaging Research and Barrow Neuroimaging Innovation Center, Barrow Neuroimaging Institute, Phoenix, AZ, United States
| | - Ashley M. Stokes
- Division of Neuroimaging Research and Barrow Neuroimaging Innovation Center, Barrow Neuroimaging Institute, Phoenix, AZ, United States
| | - Renee Chao
- Division of Neuroimaging Research and Barrow Neuroimaging Innovation Center, Barrow Neuroimaging Institute, Phoenix, AZ, United States
| | - Leland S. Hu
- Department of Radiology, Division of Neuroradiology, Mayo Clinic Arizona, Phoenix, AZ, United States
| | - Lea Alhilali
- Neuroradiology, Southwest Neuroimaging at Barrow Neurological Institute, Phoenix, AZ, United States
| | - John P. Karis
- Neuroradiology, Southwest Neuroimaging at Barrow Neurological Institute, Phoenix, AZ, United States
| | - Laura C. Bell
- Early Clinical Development, Genentech, San Francisco, CA, United States
| | - C. Chad Quarles
- Cancer System Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, United States,*Correspondence: C. Chad Quarles,
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Griffiths DR, Matthew Law L, Young C, Fuentes A, Truran S, Karamanova N, Bell LC, Turner G, Emerson H, Mastroeni D, Gonzales RJ, Reaven PD, Chad Quarles C, Migrino RQ, Lifshitz J. Chronic Cognitive and Cerebrovascular Function after Mild Traumatic Brain Injury in Rats. J Neurotrauma 2022; 39:1429-1441. [PMID: 35593008 PMCID: PMC10870816 DOI: 10.1089/neu.2022.0015] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Severe traumatic brain injury (TBI) results in cognitive dysfunction in part due to vascular perturbations. In contrast, the long-term vasculo-cognitive pathophysiology of mild TBI (mTBI) remains unknown. We evaluated mTBI effects on chronic cognitive and cerebrovascular function and assessed their interrelationships. Sprague-Dawley rats received midline fluid percussion injury (n = 20) or sham (n = 21). Cognitive function was assessed (3- and 6-month novel object recognition [NOR], novel object location [NOL], and temporal order object recognition [TOR]). Six-month cerebral blood flow (CBF) and cerebral blood volume (CBV) using contrast magnetic resonance imaging (MRI) and ex vivo circle of Willis artery endothelial and smooth muscle-dependent function were measured. mTBI rats showed significantly impaired NOR, with similar trends (non-significant) in NOL/TOR. Regional CBF and CBV were similar in sham and mTBI. NOR correlated with CBF in lateral hippocampus, medial hippocampus, and primary somatosensory barrel cortex, whereas it inversely correlated with arterial smooth muscle-dependent dilation. Six-month baseline endothelial and smooth muscle-dependent arterial function were similar among mTBI and sham, but post-angiotensin 2 stimulation, mTBI showed no change in smooth muscle-dependent dilation from baseline response, unlike the reduction in sham. mTBI led to chronic cognitive dysfunction and altered angiotensin 2-stimulated smooth muscle-dependent vasoreactivity. The findings of persistent pathophysiological consequences of mTBI in this animal model add to the broader understanding of chronic pathophysiological sequelae in human mild TBI.
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Affiliation(s)
- Daniel R. Griffiths
- Phoenix VA Health Care System, Phoenix, Arizona, USA
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, Arizona, USA
| | - L. Matthew Law
- Phoenix VA Health Care System, Phoenix, Arizona, USA
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, Arizona, USA
| | - Conor Young
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
| | | | - Seth Truran
- Phoenix VA Health Care System, Phoenix, Arizona, USA
| | | | - Laura C. Bell
- Barrow Neurological Institute, Phoenix, Arizona, USA
| | | | | | | | - Rayna J. Gonzales
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
| | - Peter D. Reaven
- Phoenix VA Health Care System, Phoenix, Arizona, USA
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
| | | | - Raymond Q. Migrino
- Phoenix VA Health Care System, Phoenix, Arizona, USA
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
| | - Jonathan Lifshitz
- Phoenix VA Health Care System, Phoenix, Arizona, USA
- University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, USA
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, Arizona, USA
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7
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McGarry SD, Brehler M, Bukowy JD, Lowman AK, Bobholz SA, Duenweg SR, Banerjee A, Hurrell SL, Malyarenko D, Chenevert TL, Cao Y, Li Y, You D, Fedorov A, Bell LC, Quarles CC, Prah MA, Schmainda KM, Taouli B, LoCastro E, Mazaheri Y, Shukla‐Dave A, Yankeelov TE, Hormuth DA, Madhuranthakam AJ, Hulsey K, Li K, Huang W, Huang W, Muzi M, Jacobs MA, Solaiyappan M, Hectors S, Antic T, Paner GP, Palangmonthip W, Jacobsohn K, Hohenwalter M, Duvnjak P, Griffin M, See W, Nevalainen MT, Iczkowski KA, LaViolette PS. Multi-Site Concordance of Diffusion-Weighted Imaging Quantification for Assessing Prostate Cancer Aggressiveness. J Magn Reson Imaging 2022; 55:1745-1758. [PMID: 34767682 PMCID: PMC9095769 DOI: 10.1002/jmri.27983] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Diffusion-weighted imaging (DWI) is commonly used to detect prostate cancer, and a major clinical challenge is differentiating aggressive from indolent disease. PURPOSE To compare 14 site-specific parametric fitting implementations applied to the same dataset of whole-mount pathologically validated DWI to test the hypothesis that cancer differentiation varies with different fitting algorithms. STUDY TYPE Prospective. POPULATION Thirty-three patients prospectively imaged prior to prostatectomy. FIELD STRENGTH/SEQUENCE 3 T, field-of-view optimized and constrained undistorted single-shot DWI sequence. ASSESSMENT Datasets, including a noise-free digital reference object (DRO), were distributed to the 14 teams, where locally implemented DWI parameter maps were calculated, including mono-exponential apparent diffusion coefficient (MEADC), kurtosis (K), diffusion kurtosis (DK), bi-exponential diffusion (BID), pseudo-diffusion (BID*), and perfusion fraction (F). The resulting parametric maps were centrally analyzed, where differentiation of benign from cancerous tissue was compared between DWI parameters and the fitting algorithms with a receiver operating characteristic area under the curve (ROC AUC). STATISTICAL TEST Levene's test, P < 0.05 corrected for multiple comparisons was considered statistically significant. RESULTS The DRO results indicated minimal discordance between sites. Comparison across sites indicated that K, DK, and MEADC had significantly higher prostate cancer detection capability (AUC range = 0.72-0.76, 0.76-0.81, and 0.76-0.80 respectively) as compared to bi-exponential parameters (BID, BID*, F) which had lower AUC and greater between site variation (AUC range = 0.53-0.80, 0.51-0.81, and 0.52-0.80 respectively). Post-processing parameters also affected the resulting AUC, moving from, for example, 0.75 to 0.87 for MEADC varying cluster size. DATA CONCLUSION We found that conventional diffusion models had consistent performance at differentiating prostate cancer from benign tissue. Our results also indicated that post-processing decisions on DWI data can affect sensitivity and specificity when applied to radiological-pathological studies in prostate cancer. LEVEL OF EVIDENCE 1 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Sean D. McGarry
- Department of BiophysicsMedical College of WisconsinMilwaukeeWisconsinUSA
| | - Michael Brehler
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA
| | - John D. Bukowy
- Department of Electrical Engineering and Computer ScienceMilwaukee School of EngineeringMilwaukeeWIUSA
| | | | - Samuel A. Bobholz
- Department of BiophysicsMedical College of WisconsinMilwaukeeWisconsinUSA
| | | | - Anjishnu Banerjee
- Division of BiostatisticsMedical College of WisconsinMilwaukeeWisconsinUSA
| | - Sarah L. Hurrell
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA
| | | | | | - Yue Cao
- Department of RadiologyUniversity of MichiganAnn ArborMichiganUSA,Department of Radiation OncologyUniversity of MichiganAnn ArborMichiganUSA
| | - Yuan Li
- Department of Radiation OncologyUniversity of MichiganAnn ArborMichiganUSA
| | - Daekeun You
- Department of Radiation OncologyUniversity of MichiganAnn ArborMichiganUSA
| | - Andrey Fedorov
- Department of RadiologyBrigham and Women's HospitalBostonMassachusettsUSA
| | - Laura C. Bell
- Division of Neuroimaging ResearchBarrow Neurological InstitutePhoenixArizonaUSA
| | - C. Chad Quarles
- Division of Neuroimaging ResearchBarrow Neurological InstitutePhoenixArizonaUSA
| | - Melissa A. Prah
- Department of BiophysicsMedical College of WisconsinMilwaukeeWisconsinUSA
| | | | - Bachir Taouli
- Department of RadiologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Eve LoCastro
- Department of Medical PhysicsMemorial Sloan Kettering Cancer CenterNew YorkNew YorkUSA
| | - Yousef Mazaheri
- Department of Medical PhysicsMemorial Sloan Kettering Cancer CenterNew YorkNew YorkUSA,Department of RadiologyMemorial Sloan Kettering Cancer CenterNew YorkNew YorkUSA
| | - Amita Shukla‐Dave
- Department of Medical PhysicsMemorial Sloan Kettering Cancer CenterNew YorkNew YorkUSA,Department of RadiologyMemorial Sloan Kettering Cancer CenterNew YorkNew YorkUSA
| | - Thomas E. Yankeelov
- Department of Biomedical Engineering, Diagnostic Medicine, Oncology, Oden Institute for Computational Engineering and Sciences, Livestrong Cancer InstitutesThe University of TexasAustinTexasUSA
| | - David A. Hormuth
- Department of Biomedical Engineering, Diagnostic Medicine, Oncology, Oden Institute for Computational Engineering and Sciences, Livestrong Cancer InstitutesThe University of TexasAustinTexasUSA
| | | | - Keith Hulsey
- Department of RadiologyThe University of Texas Southwestern Medical CenterDallasTexasUSA
| | - Kurt Li
- International School of BeavertonAlohaOregonUSA
| | - Wei Huang
- Advanced Imaging Research CenterOregon Health Sciences UniversityPortlandOregonUSA
| | - Wei Huang
- Department of PathologyOregon Health and Science UniversityMadisonWisconsinUSA
| | - Mark Muzi
- Department of Radiology, Neurology, and Radiation OncologyUniversity of WashingtonSeattleWashingtonUSA
| | - Michael A. Jacobs
- The Russell H. Morgan Department of Radiology and Radiological Science and Sidney Kimmel Comprehensive Cancer CenterJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Meiyappan Solaiyappan
- The Russell H. Morgan Department of Radiology and Radiological Science and Sidney Kimmel Comprehensive Cancer CenterJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Stefanie Hectors
- Department of biomedical engineering and imaging instituteWeill Cornell Medical CollegeNew York CityNew YorkUSA
| | - Tatjana Antic
- Department of PathologyUniversity of ChicagoChicagoIllinoisUSA
| | | | - Watchareepohn Palangmonthip
- Department of PathologyMedical College of WisconsinMilwaukeeWisconsinUSA,Department of PathologyChiang Mai UniversityChiang MaiThailand
| | - Kenneth Jacobsohn
- Department of UrologyMedical College of WisconsinMilwaukeeWisconsinUSA
| | - Mark Hohenwalter
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA
| | - Petar Duvnjak
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA
| | - Michael Griffin
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA
| | - William See
- Department of UrologyMedical College of WisconsinMilwaukeeWisconsinUSA
| | | | | | - Peter S. LaViolette
- Department of RadiologyMedical College of WisconsinMilwaukeeWIUSA,Department of Biomedical EngineeringMedical College of WisconsinMilwaukeeWisconsinUSA
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8
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Stokes AM, Bergamino M, Alhilali L, Hu LS, Karis JP, Baxter LC, Bell LC, Quarles CC. Evaluation of single bolus, dual-echo dynamic susceptibility contrast MRI protocols in brain tumor patients. J Cereb Blood Flow Metab 2021; 41:3378-3390. [PMID: 34415211 PMCID: PMC8669280 DOI: 10.1177/0271678x211039597] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Relative cerebral blood volume (rCBV) obtained from dynamic susceptibility contrast (DSC) MRI is adversely impacted by contrast agent leakage in brain tumors. Using simulations, we previously demonstrated that multi-echo DSC-MRI protocols provide improvements in contrast agent dosing, pulse sequence flexibility, and rCBV accuracy. The purpose of this study is to assess the in-vivo performance of dual-echo acquisitions in patients with brain tumors (n = 59). To verify pulse sequence flexibility, four single-dose dual-echo acquisitions were tested with variations in contrast agent dose, flip angle, and repetition time, and the resulting dual-echo rCBV was compared to standard single-echo rCBV obtained with preload (double-dose). Dual-echo rCBV was comparable to standard double-dose single-echo protocols (mean (standard deviation) tumor rCBV 2.17 (1.28) vs. 2.06 (1.20), respectively). High rCBV similarity was observed (CCC = 0.96), which was maintained across both flip angle (CCC = 0.98) and repetition time (CCC = 0.96) permutations, demonstrating that dual-echo acquisitions provide flexibility in acquisition parameters. Furthermore, a single dual-echo acquisition was shown to enable quantification of both perfusion and permeability metrics. In conclusion, single-dose dual-echo acquisitions provide similar rCBV to standard double-dose single-echo acquisitions, suggesting contrast agent dose can be reduced while providing significant pulse sequence flexibility and complementary tumor perfusion and permeability metrics.
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Affiliation(s)
- Ashley M Stokes
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Maurizio Bergamino
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Lea Alhilali
- Neuroradiology, Southwest Neuroimaging at Barrow Neurological Institute, Phoenix, AZ, USA
| | - Leland S Hu
- Department of Radiology, Division of Neuroradiology, Mayo Clinic Arizona, Phoenix, AZ, USA
| | - John P Karis
- Neuroradiology, Southwest Neuroimaging at Barrow Neurological Institute, Phoenix, AZ, USA
| | - Leslie C Baxter
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, USA.,Department of Radiology, Division of Neuroradiology, Mayo Clinic Arizona, Phoenix, AZ, USA
| | - Laura C Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, USA
| | - C Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, USA
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9
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Bell LC, Fuentes AE, Healey DR, Chao R, Bakkar N, Sirianni RW, Medina DX, Bowser RP, Ladha SS, Semmineh NB, Stokes AM, Quarles CC. Longitudinal evaluation of myofiber microstructural changes in a preclinical ALS model using the transverse relaxivity at tracer equilibrium (TRATE): A preliminary study. Magn Reson Imaging 2021; 85:217-221. [PMID: 34715291 DOI: 10.1016/j.mri.2021.10.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 12/20/2019] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 12/18/2022]
Abstract
T2⁎ relaxivity contrast imaging may serve as a potential imaging biomarker for amyotrophic lateral sclerosis (ALS) by noninvasively quantifying the tissue microstructure. In this preliminary longitudinal study, we investigated the Transverse Relaxivity at Tracer Equilibrium (TRATE) in three muscle groups between SOD1-G93A (ALS model) rat and a control population at two different timepoints. The control group was time matched to the ALS group such that the second timepoint was the onset of disease. We observed a statistically significant decrease in TRATE over time in the gastrocnemius, tibialis, and digital flexor muscles in the SOD1-G93A model (p-value = 0.003, 0.008, 0.005; respectively), whereas TRATE did not change over time in the control group (p-value = 0.4777, 0.6837, 0.9682; respectively). Immunofluorescent staining revealed a decrease in minimum fiber area and cell density in the SOD1-G93A model when compared to the control group (p-value = 6.043E-10 and 2.265E-10, respectively). These microstructural changes observed from histology align with the theorized biophysical properties of TRATE. We demonstrate that TRATE can longitudinally differentiate disease associated atrophy from healthy muscle and has potential to serve as a biomarker for disease progression and ultimately therapy response in patients with ALS.
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Affiliation(s)
- Laura C Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Alberto E Fuentes
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Deborah R Healey
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Renee Chao
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Nadine Bakkar
- Division of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Rachael W Sirianni
- Vivian L. Smith Department of Neurosurgery, University of Texas Health Science Center, Houston, TX, United States of America
| | - David X Medina
- Division of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Robert P Bowser
- Division of Neurology, Barrow Neurological Institute, Phoenix, AZ, United States of America; Division of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Shafeeq S Ladha
- Division of Neurology, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Natenael B Semmineh
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - Ashley M Stokes
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America
| | - C Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ, United States of America.
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10
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Stokes AM, Ragunathan S, Robison RK, Fuentes A, Bell LC, Karis JP, Pipe JG, Quarles CC. Development of a spiral spin- and gradient-echo (spiral-SAGE) approach for improved multi-parametric dynamic contrast neuroimaging. Magn Reson Med 2021; 86:3082-3095. [PMID: 34288112 DOI: 10.1002/mrm.28933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 02/18/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 11/09/2022]
Abstract
PURPOSE The purpose of this study was to develop a spiral-based combined spin- and gradient-echo (spiral-SAGE) method for simultaneous dynamic contrast-enhanced (DCE-MRI) and dynamic susceptibility contrast MRI (DSC-MRI). METHODS Using this sequence, we obtained gradient-echo TEs of 1.69 and 26 ms, a SE TE of 87.72 ms, with a TR of 1663 ms. Using an iterative SENSE reconstruction followed by deblurring, spiral-induced image artifacts were minimized. Healthy volunteer images are shown to demonstrate image quality using the optimized reconstruction, as well as for comparison with EPI-based SAGE. A bioreactor phantom was used to compare dynamic-contrast time courses with both spiral-SAGE and EPI-SAGE. A proof-of-concept cohort of patients with brain tumors shows the range of hemodynamic maps available using spiral-SAGE. RESULTS Comparison of spiral-SAGE images with conventional EPI-SAGE images illustrates substantial reductions of image distortion and artifactual image intensity variations. Bioreactor phantom data show similar dynamic contrast time courses between standard EPI-SAGE and spiral-SAGE for the second and third echoes, whereas first-echo data show improvements in quantifying T1 changes with shorter echo times. In a cohort of patients with brain tumors, spiral-SAGE-based perfusion and permeability maps are shown with comparison with the standard single-echo EPI perfusion map. CONCLUSION Spiral-SAGE provides a substantial improvement for the assessment of perfusion and permeability by mitigating artifacts typically encountered with EPI and by providing a shorter echo time for improved characterization of permeability. Spiral-SAGE enables quantification of perfusion, permeability, and vessel architectural parameters, as demonstrated in brain tumors.
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Affiliation(s)
- Ashley M Stokes
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Sudarshan Ragunathan
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Ryan K Robison
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA.,Philips Healthcare, Nashville, Tennessee, USA.,Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Alberto Fuentes
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Laura C Bell
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - John P Karis
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA.,Neuroradiology, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - James G Pipe
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA.,Mayo Clinic, Rochester, Minnesota, USA
| | - C Chad Quarles
- Barrow Neuroimaging Innovation Center, Barrow Neurological Institute, Phoenix, Arizona, USA
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11
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Ragunathan S, Bell LC, Semmineh N, Stokes AM, Shefner JM, Bowser R, Ladha S, Quarles CC. Evaluation of Amyotrophic Lateral Sclerosis-Induced Muscle Degeneration Using Magnetic Resonance-Based Relaxivity Contrast Imaging (RCI). ACTA ACUST UNITED AC 2021; 7:169-179. [PMID: 34062974 PMCID: PMC8162571 DOI: 10.3390/tomography7020015] [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] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 11/16/2022]
Abstract
(1) Background: This work characterizes the sensitivity of magnetic resonance-based Relaxivity Contrast Imaging (RCI) to Amyotrophic Lateral Sclerosis (ALS)-induced changes in myofiber microstructure. Transverse Relaxivity at Tracer Equilibrium (TRATE), an RCI-based parameter, was evaluated in the lower extremities of ALS patients and healthy subjects. (2) Methods: In this IRB-approved study, 23 subjects (12 ALS patients and 11 healthy controls) were scanned at 3T (Philips, The Netherlands). RCI data were obtained during injection of a gadolinium-based contrast agent. TRATE, fat fraction and T2 measures, were compared in five muscle groups of the calf muscle, between ALS and control populations. TRATE was also evaluated longitudinally (baseline and 6 months) and was compared to clinical measures, namely ALS Functional Rating Scale (ALSFRS-R) and Hand-Held Dynamometry (HHD), in a subset of the ALS population. (3) Results: TRATE was significantly lower (p < 0.001) in ALS-affected muscle than in healthy muscle in all muscle groups. Fat fraction differences between ALS and healthy muscle were statistically significant for the tibialis anterior (p = 0.01), tibialis posterior (p = 0.004), and peroneus longus (p = 0.02) muscle groups but were not statistically significant for the medial (p = 0.07) and lateral gastrocnemius (p = 0.06) muscles. T2 differences between ALS and healthy muscle were statistically significant for the tibialis anterior (p = 0.004), peroneus longus (p = 0.004) and lateral gastrocnemius (p = 0.03) muscle groups but were not statistically significant for the tibialis posterior (p = 0.06) and medial gastrocnemius (p = 0.07) muscles. Longitudinally, TRATE, averaged over all patients, decreased by 28 ± 16% in the tibialis anterior, 47 ± 18% in the peroneus longus, 25 ± 19% in the tibialis posterior, 29 ± 14% in the medial gastrocnemius and 35 ± 18% in the lateral gastrocnemius muscles between two timepoints. ALSFRS-R scores were stable in two of four ALS patients. HHD scores decreased in three of four ALS patients. (4) Conclusion: RCI-based TRATE was shown to consistently differentiate ALS-affected muscle from healthy muscle and also provide a quantitative measure of longitudinal muscle degeneration.
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Affiliation(s)
- Sudarshan Ragunathan
- Barrow Neuroimaging Innovation Center, Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (L.C.B.); (N.S.); (A.M.S.); (C.C.Q.)
- Correspondence: ; Tel.: +1-(602)-406-7884
| | - Laura C. Bell
- Barrow Neuroimaging Innovation Center, Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (L.C.B.); (N.S.); (A.M.S.); (C.C.Q.)
| | - Natenael Semmineh
- Barrow Neuroimaging Innovation Center, Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (L.C.B.); (N.S.); (A.M.S.); (C.C.Q.)
| | - Ashley M. Stokes
- Barrow Neuroimaging Innovation Center, Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (L.C.B.); (N.S.); (A.M.S.); (C.C.Q.)
| | - Jeremy M. Shefner
- Department of Neurology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (J.M.S.); (R.B.)
| | - Robert Bowser
- Department of Neurology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (J.M.S.); (R.B.)
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Shafeeq Ladha
- Gregory W. Fulton ALS and Neuromuscular Disease Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA;
| | - C. Chad Quarles
- Barrow Neuroimaging Innovation Center, Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ 85013, USA; (L.C.B.); (N.S.); (A.M.S.); (C.C.Q.)
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12
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Bell LC, Semmineh N, An H, Eldeniz C, Wahl R, Schmainda KM, Prah MA, Erickson BJ, Korfiatis P, Wu C, Sorace AG, Yankeelov TE, Rutledge N, Chenevert TL, Malyarenko D, Liu Y, Brenner A, Hu LS, Zhou Y, Boxerman JL, Yen YF, Kalpathy-Cramer J, Beers AL, Muzi M, Madhuranthakam AJ, Pinho M, Johnson B, Quarles CC. Evaluating the Use of rCBV as a Tumor Grade and Treatment Response Classifier Across NCI Quantitative Imaging Network Sites: Part II of the DSC-MRI Digital Reference Object (DRO) Challenge. Tomography 2020; 6:203-208. [PMID: 32548297 PMCID: PMC7289259 DOI: 10.18383/j.tom.2020.00012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have previously characterized the reproducibility of brain tumor relative cerebral blood volume (rCBV) using a dynamic susceptibility contrast magnetic resonance imaging digital reference object across 12 sites using a range of imaging protocols and software platforms. As expected, reproducibility was highest when imaging protocols and software were consistent, but decreased when they were variable. Our goal in this study was to determine the impact of rCBV reproducibility for tumor grade and treatment response classification. We found that varying imaging protocols and software platforms produced a range of optimal thresholds for both tumor grading and treatment response, but the performance of these thresholds was similar. These findings further underscore the importance of standardizing acquisition and analysis protocols across sites and software benchmarking.
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Affiliation(s)
- Laura C. Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
| | - Natenael Semmineh
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
| | - Hongyu An
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Cihat Eldeniz
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Richard Wahl
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Kathleen M. Schmainda
- Departments of Radiology; and
- Biophysics, Medical College of Wisconsin, Milwaukee, WI
| | | | | | | | - Chengyue Wu
- Oden Institute for Computational Engineering and Sciences, Departments of Biomedical Engineering, Diagnostic Medicine, and Oncology, Livestrong Cancer Institutes, University of Texas at Austin, Austin, TX
| | - Anna G. Sorace
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL
| | - Thomas E. Yankeelov
- Oden Institute for Computational Engineering and Sciences, Departments of Biomedical Engineering, Diagnostic Medicine, and Oncology, Livestrong Cancer Institutes, University of Texas at Austin, Austin, TX
| | - Neal Rutledge
- Oden Institute for Computational Engineering and Sciences, Departments of Biomedical Engineering, Diagnostic Medicine, and Oncology, Livestrong Cancer Institutes, University of Texas at Austin, Austin, TX
| | | | | | - Yichu Liu
- UT Health San Antonio, San Antonio, TX
| | | | - Leland S. Hu
- Department of Radiology, Mayo Clinic, Scottsdale, AZ
| | - Yuxiang Zhou
- Department of Radiology, Mayo Clinic, Scottsdale, AZ
| | - Jerrold L. Boxerman
- Department of Diagnostic Imaging, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Yi-Fen Yen
- Department of Radiology, MGH—Martinos Center for Biomedical Imaging, Boston, MA
| | | | - Andrew L. Beers
- Department of Radiology, MGH—Martinos Center for Biomedical Imaging, Boston, MA
| | - Mark Muzi
- Radiology, University of Washington, Seattle, WA
| | | | - Marco Pinho
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX; and
| | - Brian Johnson
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX; and
- Philips Healthcare, Gainesville, FL
| | - C. Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
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13
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Lee MD, Baird GL, Bell LC, Quarles CC, Boxerman JL. Utility of Percentage Signal Recovery and Baseline Signal in DSC-MRI Optimized for Relative CBV Measurement for Differentiating Glioblastoma, Lymphoma, Metastasis, and Meningioma. AJNR Am J Neuroradiol 2019; 40:1445-1450. [PMID: 31371360 DOI: 10.3174/ajnr.a6153] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 06/21/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE The percentage signal recovery in non-leakage-corrected (no preload, high flip angle, intermediate TE) DSC-MR imaging is known to differ significantly for glioblastoma, metastasis, and primary CNS lymphoma. Because the percentage signal recovery is influenced by preload and pulse sequence parameters, we investigated whether the percentage signal recovery can still differentiate these common contrast-enhancing neoplasms using a DSC-MR imaging protocol designed for relative CBV accuracy (preload, intermediate flip angle, low TE). MATERIALS AND METHODS We retrospectively analyzed DSC-MR imaging of treatment-naïve, pathology-proved glioblastomas (n = 14), primary central nervous system lymphomas (n = 7), metastases (n = 20), and meningiomas (n = 13) using a protocol designed for relative CBV accuracy (a one-quarter-dose preload and single-dose bolus of gadobutrol, TR/TE = 1290/40 ms, flip angle = 60° at 1.5T). Mean percentage signal recovery, relative CBV, and normalized baseline signal intensity were compared within contrast-enhancing lesion volumes. Classification accuracy was determined by receiver operating characteristic analysis. RESULTS Relative CBV best differentiated meningioma from glioblastoma and from metastasis with areas under the curve of 0.84 and 0.82, respectively. The percentage signal recovery best differentiated primary central nervous system lymphoma from metastasis with an area under the curve of 0.81. Relative CBV and percentage signal recovery were similar in differentiating primary central nervous system lymphoma from glioblastoma and from meningioma. Although neither relative CBV nor percentage signal recovery differentiated glioblastoma from metastasis, mean normalized baseline signal intensity achieved 86% sensitivity and 50% specificity. CONCLUSIONS Similar to results for non-preload-based DSC-MR imaging, percentage signal recovery for one-quarter-dose preload-based, intermediate flip angle DSC-MR imaging differentiates most pair-wise comparisons of glioblastoma, metastasis, primary central nervous system lymphoma, and meningioma, except for glioblastoma versus metastasis. Differences in normalized post-preload baseline signal for glioblastoma and metastasis, reflecting a snapshot of dynamic contrast enhancement, may motivate the use of single-dose multiecho protocols permitting simultaneous quantification of DSC-MR imaging and dynamic contrast-enhanced MR imaging parameters.
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Affiliation(s)
- M D Lee
- From the Warren Alpert Medical School of Brown University (M.D.L., J.L.B.), Providence, Rhode Island
| | - G L Baird
- Department of Diagnostic Imaging (G.L.B., J.L.B.), Rhode Island Hospital, Providence, Rhode Island
| | - L C Bell
- Division of Neuroimaging Research (L.C.B., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - C C Quarles
- Division of Neuroimaging Research (L.C.B., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - J L Boxerman
- From the Warren Alpert Medical School of Brown University (M.D.L., J.L.B.), Providence, Rhode Island
- Department of Diagnostic Imaging (G.L.B., J.L.B.), Rhode Island Hospital, Providence, Rhode Island
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14
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Stokes AM, Semmineh NB, Nespodzany A, Bell LC, Quarles CC. Systematic assessment of multi-echo dynamic susceptibility contrast MRI using a digital reference object. Magn Reson Med 2019; 83:109-123. [PMID: 31400035 DOI: 10.1002/mrm.27914] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 02/11/2019] [Revised: 06/14/2019] [Accepted: 07/02/2019] [Indexed: 11/07/2022]
Abstract
PURPOSE Brain tumor dynamic susceptibility contrast (DSC) MRI is adversely impacted by T1 and T 2 ∗ contrast agent leakage effects that result in inaccurate hemodynamic metrics. While multi-echo acquisitions remove T1 leakage effects, there is no consensus on the optimal set of acquisition parameters. Using a computational approach, we systematically evaluated a wide range of acquisition strategies to determine the optimal multi-echo DSC-MRI perfusion protocol. METHODS Using a population-based DSC-MRI digital reference object (DRO), we assessed the influence of preload dosing (no preload and full dose preload), field strength (1.5 and 3T), pulse sequence parameters (echo time, repetition time, and flip angle), and leakage correction on relative cerebral blood volume (rCBV) and flow (rCBF) accuracy. We also compared multi-echo DSC-MRI protocols with standard single-echo protocols. RESULTS Multi-echo DSC-MRI is highly consistent across all protocols, and multi-echo rCBV (with or without use of a preload dose) had higher accuracy than single-echo rCBV. Regression analysis showed that choice of repetition time and flip angle had minimal impact on multi-echo rCBV and rCBV, indicating the potential for significant flexibility in acquisition parameters. The echo time combination had minimal impact on rCBV, though longer echo times should be avoided, particularly at higher field strengths. Leakage correction improved rCBV accuracy in all cases. Multi-echo rCBF was less biased than single-echo rCBF, although rCBF accuracy was reduced overall relative to rCBV. CONCLUSIONS Multi-echo acquisitions were more robust than single-echo, essentially decoupling both repetition time and flip angle from rCBV accuracy. Multi-echo acquisitions obviate the need for preload dosing, although leakage correction to remove residual T 2 ∗ leakage effects remains compulsory for high rCBV accuracy.
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Affiliation(s)
- Ashley M Stokes
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Natenael B Semmineh
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Ashley Nespodzany
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Laura C Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - C Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona
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15
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Bell LC, Stokes AM, Quarles CC. Analysis of postprocessing steps for residue function dependent dynamic susceptibility contrast (DSC)-MRI biomarkers and their clinical impact on glioma grading for both 1.5 and 3T. J Magn Reson Imaging 2019; 51:547-553. [PMID: 31206948 DOI: 10.1002/jmri.26837] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 03/08/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Dynamic susceptibility contrast (DSC)-MRI analysis pipelines differ across studies and sites, potentially confounding the clinical value and use of the derived biomarkers. PURPOSE/HYPOTHESIS To investigate how postprocessing steps for computation of cerebral blood volume (CBV) and residue function dependent parameters (cerebral blood flow [CBF], mean transit time [MTT], capillary transit heterogeneity [CTH]) impact glioma grading. STUDY TYPE Retrospective study from The Cancer Imaging Archive (TCIA). POPULATION Forty-nine subjects with low- and high-grade gliomas. FIELD STRENGTH/SEQUENCE 1.5 and 3.0T clinical systems using a single-echo echo planar imaging (EPI) acquisition. ASSESSMENT Manual regions of interest (ROIs) were provided by TCIA and automatically segmented ROIs were generated by k-means clustering. CBV was calculated based on conventional equations. Residue function dependent biomarkers (CBF, MTT, CTH) were found by two deconvolution methods: circular discretization followed by a signal-to-noise ratio (SNR)-adapted eigenvalue thresholding (Method 1) and Volterra discretization with L-curve-based Tikhonov regularization (Method 2). STATISTICAL TESTS Analysis of variance, receiver operating characteristics (ROC), and logistic regression tests. RESULTS MTT alone was unable to statistically differentiate glioma grade (P > 0.139). When normalized, tumor CBF, CTH, and CBV did not differ across field strengths (P > 0.141). Biomarkers normalized to automatically segmented regions performed equally (rCTH AUROC is 0.73 compared with 0.74) or better (rCBF AUROC increases from 0.74-0.84; rCBV AUROC increases 0.78-0.86) than manually drawn ROIs. By updating the current deconvolution steps (Method 2), rCTH can act as a classifier for glioma grade (P < 0.007), but not if processed by current conventional DSC methods (Method 1) (P > 0.577). Lastly, higher-order biomarkers (eg, rCBF and rCTH) along with rCBV increases AUROC to 0.92 for differentiating tumor grade as compared with 0.78 and 0.86 (manual and automatic reference regions, respectively) for rCBV alone. DATA CONCLUSION With optimized analysis pipelines, higher-order perfusion biomarkers (rCBF and rCTH) improve glioma grading as compared with CBV alone. Additionally, postprocessing steps impact thresholds needed for glioma grading. LEVEL OF EVIDENCE 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:547-553.
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Affiliation(s)
- Laura C Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Ashley M Stokes
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - C Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, Arizona, USA
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Bell LC, Semmineh N, An H, Eldeniz C, Wahl R, Schmainda KM, Prah MA, Erickson BJ, Korfiatis P, Wu C, Sorace AG, Yankeelov TE, Rutledge N, Chenevert TL, Malyarenko D, Liu Y, Brenner A, Hu LS, Zhou Y, Boxerman JL, Yen YF, Kalpathy-Cramer J, Beers AL, Muzi M, Madhuranthakam AJ, Pinho M, Johnson B, Quarles CC. Evaluating Multisite rCBV Consistency from DSC-MRI Imaging Protocols and Postprocessing Software Across the NCI Quantitative Imaging Network Sites Using a Digital Reference Object (DRO). Tomography 2019; 5:110-117. [PMID: 30854448 PMCID: PMC6403027 DOI: 10.18383/j.tom.2018.00041] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Relative cerebral blood volume (rCBV) cannot be used as a response metric in clinical trials, in part, because of variations in biomarker consistency and associated interpretation across sites, stemming from differences in image acquisition and postprocessing methods (PMs). This study leveraged a dynamic susceptibility contrast magnetic resonance imaging digital reference object to characterize rCBV consistency across 12 sites participating in the Quantitative Imaging Network (QIN), specifically focusing on differences in site-specific imaging protocols (IPs; n = 17), and PMs (n = 19) and differences due to site-specific IPs and PMs (n = 25). Thus, high agreement across sites occurs when 1 managing center processes rCBV despite slight variations in the IP. This result is most likely supported by current initiatives to standardize IPs. However, marked intersite disagreement was observed when site-specific software was applied for rCBV measurements. This study's results have important implications for comparing rCBV values across sites and trials, where variability in PMs could confound the comparison of therapeutic effectiveness and/or any attempts to establish thresholds for categorical response to therapy. To overcome these challenges and ensure the successful use of rCBV as a clinical trial biomarker, we recommend the establishment of qualifying and validating site- and trial-specific criteria for scanners and acquisition methods (eg, using a validated phantom) and the software tools used for dynamic susceptibility contrast magnetic resonance imaging analysis (eg, using a digital reference object where the ground truth is known).
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Affiliation(s)
- Laura C. Bell
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
| | - Natenael Semmineh
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
| | - Hongyu An
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Cihat Eldeniz
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Richard Wahl
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO
| | - Kathleen M. Schmainda
- Departments of Radiology and Biophysics, Medical College of Wisconsin, Wauwatosa, WI
| | - Melissa A. Prah
- Departments of Radiology and Biophysics, Medical College of Wisconsin, Wauwatosa, WI
| | | | | | - Chengyue Wu
- Department of Diagnostic Medicine, University of Texas at Austin, Austin, TX
| | - Anna G. Sorace
- Department of Diagnostic Medicine, University of Texas at Austin, Austin, TX
| | - Thomas E. Yankeelov
- Department of Diagnostic Medicine, University of Texas at Austin, Austin, TX
| | - Neal Rutledge
- Department of Diagnostic Medicine, University of Texas at Austin, Austin, TX
| | | | | | - Yichu Liu
- UT Health San Antonio, San Antonio, TX
| | | | - Leland S. Hu
- Department of Radiology, Mayo Clinic, Scottsdale, AZ
| | - Yuxiang Zhou
- Department of Radiology, Mayo Clinic, Scottsdale, AZ
| | - Jerrold L. Boxerman
- Department of Diagnostic Imaging, Rhode Island Hospital, Providence, RI;,Alpert Medical School of Brown University, Providence, RI
| | - Yi-Fen Yen
- Department of Radiology, Massachusetts General Hospital, Boston, MA
| | | | - Andrew L. Beers
- Department of Radiology, Massachusetts General Hospital, Boston, MA
| | - Mark Muzi
- Department of Radiology, University of Washington, Seattle, Washington
| | | | - Marco Pinho
- UT Southwestern Medical Center, Dallas, TX; and
| | - Brian Johnson
- UT Southwestern Medical Center, Dallas, TX; and,Philips Healthcare, Gainesville, FL
| | - C. Chad Quarles
- Division of Neuroimaging Research, Barrow Neurological Institute, Phoenix, AZ
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Semmineh NB, Bell LC, Stokes AM, Hu LS, Boxerman JL, Quarles CC. Optimization of Acquisition and Analysis Methods for Clinical Dynamic Susceptibility Contrast MRI Using a Population-Based Digital Reference Object. AJNR Am J Neuroradiol 2018; 39:1981-1988. [PMID: 30309842 PMCID: PMC6239921 DOI: 10.3174/ajnr.a5827] [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: 03/08/2018] [Accepted: 06/08/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The accuracy of DSC-MR imaging CBV maps in glioblastoma depends on acquisition and analysis protocols. Multisite protocol heterogeneity has challenged standardization initiatives due to the difficulties of in vivo validation. This study sought to compare the accuracy of routinely used protocols using a digital reference object. MATERIALS AND METHODS The digital reference object consisted of approximately 10,000 simulated voxels recapitulating typical signal heterogeneity encountered in vivo. The influence of acquisition and postprocessing methods on CBV reliability was evaluated across 6912 parameter combinations, including contrast agent dosing schemes, pulse sequence parameters, field strengths, and postprocessing methods. Accuracy and precision were assessed using the concordance correlation coefficient and coefficient of variation. RESULTS Across all parameter space, the optimal protocol included full-dose contrast agent preload and bolus, intermediate (60°) flip angle, 30-ms TE, and postprocessing with a leakage-correction algorithm (concordance correlation coefficient = 0.97, coefficient of variation = 6.6%). Protocols with no preload or fractional dose preload and bolus using these acquisition parameters were generally less robust. However, a protocol with no preload, full-dose bolus, and low (30°) flip angle performed very well (concordance correlation coefficient = 0.93, coefficient of variation = 8.7% at 1.5T and concordance correlation coefficient = 0.92, coefficient of variation = 8.2% at 3T). CONCLUSIONS Schemes with full-dose preload and bolus maximize CBV accuracy and reduce variability, which could enable smaller sample sizes and more reliable detection of CBV changes in clinical trials. When a lower total contrast agent dose is desired, use of a low flip angle, no preload, and full-dose bolus protocol may provide an attractive alternative.
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Affiliation(s)
- N B Semmineh
- From the Department of Imaging Research (N.B.S., L.C.B., A.M.S., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - L C Bell
- From the Department of Imaging Research (N.B.S., L.C.B., A.M.S., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - A M Stokes
- From the Department of Imaging Research (N.B.S., L.C.B., A.M.S., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - L S Hu
- Department of Radiology (L.S.H.), Mayo Clinic Arizona, Phoenix, Arizona
| | - J L Boxerman
- Department of Diagnostic Imaging (J.L.B.), Rhode Island Hospital, Providence, Rhode Island
| | - C C Quarles
- From the Department of Imaging Research (N.B.S., L.C.B., A.M.S., C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
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Quarles CC, Bell LC, Stokes AM. Imaging vascular and hemodynamic features of the brain using dynamic susceptibility contrast and dynamic contrast enhanced MRI. Neuroimage 2018; 187:32-55. [PMID: 29729392 DOI: 10.1016/j.neuroimage.2018.04.069] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 04/27/2018] [Accepted: 04/29/2018] [Indexed: 12/22/2022] Open
Abstract
In the context of neurologic disorders, dynamic susceptibility contrast (DSC) and dynamic contrast enhanced (DCE) MRI provide valuable insights into cerebral vascular function, integrity, and architecture. Even after two decades of use, these modalities continue to evolve as their biophysical and kinetic basis is better understood, with improvements in pulse sequences and accelerated imaging techniques and through application of more robust and automated data analysis strategies. Here, we systematically review each of these elements, with a focus on how their integration improves kinetic parameter accuracy and the development of new hemodynamic biomarkers that provide sub-voxel sensitivity (e.g., capillary transit time and flow heterogeneity). Regarding contrast mechanisms, we discuss the dipole-dipole interactions and susceptibility effects that give rise to simultaneous T1, T2 and T2∗ relaxation effects, including their quantification, influence on pulse sequence parameter optimization, and use in methods such as vessel size and vessel architectural imaging. The application of technologic advancements, such as parallel imaging, simultaneous multi-slice, undersampled k-space acquisitions, and sliding window strategies, enables improved spatial and/or temporal resolution of DSC and DCE acquisitions. Such acceleration techniques have also enabled the implementation of, clinically feasible, simultaneous multi-echo spin- and gradient echo acquisitions, providing more comprehensive and quantitative interrogation of T1, T2 and T2∗ changes. Characterizing these relaxation rate changes through different post-processing options allows for the quantification of hemodynamics and vascular permeability. The application of different biophysical models provides insight into traditional hemodynamic parameters (e.g., cerebral blood volume) and more advanced parameters (e.g., capillary transit time heterogeneity). We provide insight into the appropriate selection of biophysical models and the necessary post-processing steps to ensure reliable measurements while minimizing potential sources of error. We show representative examples of advanced DSC- and DCE-MRI methods applied to pathologic conditions affecting the cerebral microcirculation, including brain tumors, stroke, aging, and multiple sclerosis. The maturation and standardization of conventional DSC- and DCE-MRI techniques has enabled their increased integration into clinical practice and use in clinical trials, which has, in turn, spurred renewed interest in their technological and biophysical development, paving the way towards a more comprehensive assessment of cerebral hemodynamics.
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Affiliation(s)
- C Chad Quarles
- Division of Neuro imaging Research, Barrow Neurological Institute, 350 W. Thomas Rd, Phoenix, AZ, USA.
| | - Laura C Bell
- Division of Neuro imaging Research, Barrow Neurological Institute, 350 W. Thomas Rd, Phoenix, AZ, USA
| | - Ashley M Stokes
- Division of Neuro imaging Research, Barrow Neurological Institute, 350 W. Thomas Rd, Phoenix, AZ, USA
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Zha W, Kruger SJ, Johnson KM, Cadman RV, Bell LC, Liu F, Hahn AD, Evans MD, Nagle SK, Fain SB. Pulmonary ventilation imaging in asthma and cystic fibrosis using oxygen-enhanced 3D radial ultrashort echo time MRI. J Magn Reson Imaging 2017; 47:1287-1297. [PMID: 29086454 DOI: 10.1002/jmri.25877] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 10/10/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND A previous study demonstrated the feasibility of using 3D radial ultrashort echo time (UTE) oxygen-enhanced MRI (UTE OE-MRI) for functional imaging of healthy human lungs. The repeatability of quantitative measures from UTE OE-MRI needs to be established prior to its application in clinical research. PURPOSE To evaluate repeatability of obstructive patterns in asthma and cystic fibrosis (CF) with UTE OE-MRI with isotropic spatial resolution and full chest coverage. STUDY TYPE Volunteer and patient repeatability. POPULATION Eighteen human subjects (five asthma, six CF, and seven normal subjects). FIELD STRENGTH/SEQUENCE Respiratory-gated free-breathing 3D radial UTE (80 μs) sequence at 1.5T. ASSESSMENT Two 3D radial UTE volumes were acquired sequentially under normoxic and hyperoxic conditions. A subset of subjects underwent repeat acquisitions on either the same day or ≤15 days apart. Asthma and CF subjects also underwent spirometry. A workflow including deformable registration and retrospective lung density correction was used to compute 3D isotropic percent signal enhancement (PSE) maps. Median PSE (MPSE) and ventilation defect percent (VDP) of the lung were measured from the PSE map. STATISTICAL TESTS The relations between MPSE, VDP, and spirometric measures were assessed using Spearman correlations. The test-retest repeatability was evaluated using Bland-Altman analysis and intraclass correlation coefficients (ICC). RESULTS Ventilation measures in normal subjects (MPSE = 8.0%, VDP = 3.3%) were significantly different from those in asthma (MPSE = 6.0%, P = 0.042; VDP = 21.7%, P = 0.018) and CF group (MPSE = 4.5%, P = 0.0006; VDP = 27.2%, P = 0.002). MPSE correlated significantly with forced expiratory lung volume in 1 second percent predicted (ρ = 0.72, P = 0.017). The ICC of the test-retest VDP and MPSE were both ≥0.90. In all subject groups, an anterior/posterior gradient was observed with higher MPSE and lower VDP in the posterior compared to anterior regions (P ≤ 0.0021 for all comparisons). DATA CONCLUSION 3D radial UTE OE-MRI supports quantitative differentiation of diseased vs. healthy lungs using either whole lung VDP or MPSE with excellent test-retest repeatability. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1287-1297.
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Affiliation(s)
- Wei Zha
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Stanley J Kruger
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Kevin M Johnson
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Robert V Cadman
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Laura C Bell
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Fang Liu
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Andrew D Hahn
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Michael D Evans
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Scott K Nagle
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Pediatrics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Sean B Fain
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA
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Bell LC, Does MD, Stokes AM, Baxter LC, Schmainda KM, Dueck AC, Quarles CC. Optimization of DSC MRI Echo Times for CBV Measurements Using Error Analysis in a Pilot Study of High-Grade Gliomas. AJNR Am J Neuroradiol 2017; 38:1710-1715. [PMID: 28684456 PMCID: PMC5591773 DOI: 10.3174/ajnr.a5295] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 05/07/2017] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The optimal TE must be calculated to minimize the variance in CBV measurements made with DSC MR imaging. Simulations can be used to determine the influence of the TE on CBV, but they may not adequately recapitulate the in vivo heterogeneity of precontrast T2*, contrast agent kinetics, and the biophysical basis of contrast agent-induced T2* changes. The purpose of this study was to combine quantitative multiecho DSC MRI T2* time curves with error analysis in order to compute the optimal TE for a traditional single-echo acquisition. MATERIALS AND METHODS Eleven subjects with high-grade gliomas were scanned at 3T with a dual-echo DSC MR imaging sequence to quantify contrast agent-induced T2* changes in this retrospective study. Optimized TEs were calculated with propagation of error analysis for high-grade glial tumors, normal-appearing white matter, and arterial input function estimation. RESULTS The optimal TE is a weighted average of the T2* values that occur as a contrast agent bolus transverses a voxel. The mean optimal TEs were 30.0 ± 7.4 ms for high-grade glial tumors, 36.3 ± 4.6 ms for normal-appearing white matter, and 11.8 ± 1.4 ms for arterial input function estimation (repeated-measures ANOVA, P < .001). CONCLUSIONS Greater heterogeneity was observed in the optimal TE values for high-grade gliomas, and mean values of all 3 ROIs were statistically significant. The optimal TE for the arterial input function estimation is much shorter; this finding implies that quantitative DSC MR imaging acquisitions would benefit from multiecho acquisitions. In the case of a single-echo acquisition, the optimal TE prescribed should be 30-35 ms (without a preload) and 20-30 ms (with a standard full-dose preload).
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Affiliation(s)
- L C Bell
- From the Division of Imaging Research (L.C. Bell, A.M.S., L.C. Baxter, C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - M D Does
- Department of Biomedical Engineering (M.D.D.), Vanderbilt University Institute of Imaging Science, Nashville, Tennessee
| | - A M Stokes
- From the Division of Imaging Research (L.C. Bell, A.M.S., L.C. Baxter, C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - L C Baxter
- From the Division of Imaging Research (L.C. Bell, A.M.S., L.C. Baxter, C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
| | - K M Schmainda
- Departments of Biophysics and Radiology (K.M.S.), Medical College of Wisconsin, Milwaukee, Wisconsin
| | - A C Dueck
- Division of Health Sciences Research (A.C.D.), Section of Biostatistics, Mayo Clinic, Scottsdale, Arizona
| | - C C Quarles
- From the Division of Imaging Research (L.C. Bell, A.M.S., L.C. Baxter, C.C.Q.), Barrow Neurological Institute, Phoenix, Arizona
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Bell LC, Hu LS, Stokes AM, McGee SC, Baxter LC, Quarles CC. Characterizing the Influence of Preload Dosing on Percent Signal Recovery (PSR) and Cerebral Blood Volume (CBV) Measurements in a Patient Population With High-Grade Glioma Using Dynamic Susceptibility Contrast MRI. ACTA ACUST UNITED AC 2017; 3:89-95. [PMID: 28825039 PMCID: PMC5557059 DOI: 10.18383/j.tom.2017.00004] [Citation(s) in RCA: 14] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
With DSC-MRI, contrast agent leakage effects in brain tumors can either be leveraged for percent signal recovery (PSR) measurements or be adequately resolved for accurate relative cerebral blood volume (rCBV) measurements. Leakage effects can be dimished by administration of a preload dose before imaging and/or specific postprocessing steps. This study compares the consistency of both PSR and rCBV measurements as a function of varying preload doses in a retrospective analysis of 14 subjects with high-grade gliomas. The scans consisted of 6 DSC-MRI scans during 6 sequential bolus injections (0.05 mmol/kg). Mean PSR was calculated for tumor and normal-appearing white matter regions of interest. DSC-MRI data were corrected for leakage effects before computing mean tumor rCBV. Statistical differences were seen across varying preloads for tumor PSR (P value = 4.57E-24). Tumor rCBV values did not exhibit statistically significant differences across preloads (P value = .14) and were found to be highly consistent for clinically relevant preloads (intraclass correlation coefficient = 0.93). For a 0.05 mmol/kg injection bolus and pulse sequence parameters used, the highest PSR contrast between normal-appearing white matter and tumor occurs when no preload is used. This suggests that studies using PSR as a biomarker should acquire DSC-MRI data without preload. The finding that leakage-corrected rCBV values do not depend on the presence or dose of preload contradicts that of previous studies with dissimilar acquisition protocols. This further confirms the sensitivity of rCBV to preload dosing schemes and pulse sequence parameters and highlights the importance of standardization efforts for achieving multisite rCBV consistency.
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Affiliation(s)
- Laura C Bell
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Leland S Hu
- Department of Radiology, Mayo Clinic Arizona, Scottsdale, Arizona
| | - Ashley M Stokes
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Samuel C McGee
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Leslie C Baxter
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - C Chad Quarles
- Division of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
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Semmineh NB, Stokes AM, Bell LC, Boxerman JL, Quarles CC. A Population-Based Digital Reference Object (DRO) for Optimizing Dynamic Susceptibility Contrast (DSC)-MRI Methods for Clinical Trials. ACTA ACUST UNITED AC 2017; 3:41-49. [PMID: 28584878 PMCID: PMC5454781 DOI: 10.18383/j.tom.2016.00286] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The standardization and broad-scale integration of dynamic susceptibility contrast (DSC)-magnetic resonance imaging (MRI) have been confounded by a lack of consensus on DSC-MRI methodology for preventing potential relative cerebral blood volume inaccuracies, including the choice of acquisition protocols and postprocessing algorithms. Therefore, we developed a digital reference object (DRO), using physiological and kinetic parameters derived from in vivo data, unique voxel-wise 3-dimensional tissue structures, and a validated MRI signal computational approach, aimed at validating image acquisition and analysis methods for accurately measuring relative cerebral blood volume in glioblastomas. To achieve DSC-MRI signals representative of the temporal characteristics, magnitude, and distribution of contrast agent-induced T1 and T2* changes observed across multiple glioblastomas, the DRO's input parameters were trained using DSC-MRI data from 23 glioblastomas (>40 000 voxels). The DRO's ability to produce reliable signals for combinations of pulse sequence parameters and contrast agent dosing schemes unlike those in the training data set was validated by comparison with in vivo dual-echo DSC-MRI data acquired in a separate cohort of patients with glioblastomas. Representative applications of the DRO are presented, including the selection of DSC-MRI acquisition and postprocessing methods that optimize CBV accuracy, determination of the impact of DSC-MRI methodology choices on sample size requirements, and the assessment of treatment response in clinical glioblastoma trials.
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Affiliation(s)
- Natenael B Semmineh
- Department of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Ashley M Stokes
- Department of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Laura C Bell
- Department of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
| | - Jerrold L Boxerman
- Department of Diagnostic Imaging, RI Hospital and Alpert Medical School of Brown University, Providence, Rhode Island
| | - C Chad Quarles
- Department of Imaging Research, Barrow Neurological Institute, Phoenix, Arizona
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Wang K, Beatty PJ, Nagle SK, Reeder SB, Holmes JH, Rahimi MS, Bell LC, Korosec FR, Brittain JH. Application of direct virtual coil to dynamic contrast-enhanced MRI and MR angiography with data-driven parallel imaging. Magn Reson Med 2015; 71:783-9. [PMID: 23441013 DOI: 10.1002/mrm.24686] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE To demonstrate the feasibility of direct virtual coil (DVC) in the setting of 4D dynamic imaging used in multiple clinical applications. THEORY AND METHODS Three dynamic imaging applications were chosen: pulmonary perfusion, liver perfusion, and peripheral MR angiography (MRA), with 18, 11, and 10 subjects, respectively. After view-sharing, the k-space data were reconstructed twice: once with channel-by-channel (CBC) followed by sum-of-squares coil combination and once with DVC. Images reconstructed using CBC and DVC were compared and scored based on overall image quality by two experienced radiologists using a five-point scale. RESULTS The CBC and DVC showed similar image quality in image domain. Time course measurements also showed good agreement in the temporal domain. CBC and DVC images were scored as equivalent for all pulmonary perfusion cases, all liver perfusion cases, and four of the 10 peripheral MRA cases. For the remaining six peripheral MRA cases, DVC were scored as slightly better (not clinically significant) than the CBC images by Radiologist A and as equivalent by Radiologist B. CONCLUSION For dynamic contrast-enhanced MR applications, it is clinically feasible to reduce image reconstruction time while maintaining image quality and time course measurement using the DVC technique.
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Affiliation(s)
- Kang Wang
- Global Applied Science Laboratory, GE Healthcare, Madison, Wisconsin, USA
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Bannas P, Bell LC, Johnson KM, Schiebler ML, François CJ, Motosugi U, Consigny D, Reeder SB, Nagle SK. Pulmonary Embolism Detection with Three-dimensional Ultrashort Echo Time MR Imaging: Experimental Study in Canines. Radiology 2015; 278:413-21. [PMID: 26422185 DOI: 10.1148/radiol.2015150606] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE To demonstrate the feasibility of free-breathing three-dimensional (3D) radial ultrashort echo time (UTE) magnetic resonance (MR) imaging in the simultaneous detection of pulmonary embolism (PE) and high-quality evaluation of lung parenchyma. MATERIALS AND METHODS The institutional animal care committee approved this study. A total of 12 beagles underwent MR imaging and computed tomography (CT) before and after induction of PE with autologous clots. Breath-hold 3D MR angiography and free-breathing 3D radial UTE (1.0-mm isotropic spatial resolution; echo time, 0.08 msec) were performed at 3 T. Two blinded radiologists independently marked and graded all PEs on a four-point scale (1 = low confidence, 4 = absolutely certain) on MR angiographic and UTE images. Image quality of pulmonary arteries and lung parenchyma was scored on a four-point-scale (1 = poor, 4 = excellent). Locations and ratings of emboli were compared with reference standard CT images by using an alternative free-response receiver operating characteristic curve (AFROC) method. Areas under the curve and image quality ratings were compared by using the F test and the Wilcoxon signed-rank test. RESULTS A total of 48 emboli were detected with CT. Both readers showed higher sensitivity for PE detection with UTE (83% and 79%) than with MR angiography (75% and 71%). The AFROC area under the curve was higher for UTE than for MR angiography (0.95 vs 0.89), with a significant difference in area under the curve of 0.06 (95% confidence interval: 0.01, 0.11; P = .018). UTE image quality exceeded that of MR angiography for subsegmental arteries (3.5 ± 0.7 vs 2.9 ± 0.5, P = .002) and lung parenchyma (3.8 ± 0.5 vs 2.2 ± 0.2, P < .001). The apparent signal-to-noise ratio in pulmonary arteries and lung parenchyma was significantly higher for UTE than for MR angiography (41.0 ± 5.2 vs 24.5 ± 6.2 [P < .001] and 10.2 ± 1.8 vs 3.5 ± 0.8 [P < .001], respectively). The apparent contrast-to-noise ratio between arteries and PEs was higher for UTE than for MR angiography (20.3 ± 5.2 vs 15.4 ± 6.7, P = .055). CONCLUSION In a canine model, free-breathing 3D radial UTE performs better than breath-hold 3D MR angiography in the detection of PE and yields better image quality for visualization of small vessels and lung parenchyma. Free-breathing 3D radial UTE for detection of PE is feasible and warrants evaluation in human subjects.
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Affiliation(s)
- Peter Bannas
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Laura C Bell
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Kevin M Johnson
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Mark L Schiebler
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Christopher J François
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Utaroh Motosugi
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Daniel Consigny
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Scott B Reeder
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
| | - Scott K Nagle
- From the Departments of Radiology (P.B., M.L.S., C.J.F., U.M., D.C., S.B.R., S.K.N.), Medical Physics (L.C.B., K.M.J., S.B.R., S.K.N.), Biomedical Engineering (S.B.R.), Medicine (S.B.R.), Emergency Medicine (S.B.R.), and Pediatrics (S.K.N.), University of Wisconsin-Madison, 600 Highland Ave, Madison, WI 53792-3252
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Bauman G, Johnson KM, Bell LC, Velikina JV, Samsonov AA, Nagle SK, Fain SB. Three-dimensional pulmonary perfusion MRI with radial ultrashort echo time and spatial-temporal constrained reconstruction. Magn Reson Med 2015; 73:555-64. [PMID: 24604452 PMCID: PMC4156934 DOI: 10.1002/mrm.25158] [Citation(s) in RCA: 24] [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: 10/11/2013] [Revised: 01/06/2014] [Accepted: 01/09/2014] [Indexed: 12/23/2022]
Abstract
PURPOSE To assess the feasibility of spatial-temporal constrained reconstruction for accelerated regional lung perfusion using highly undersampled dynamic contrast-enhanced (DCE) three-dimensional (3D) radial MRI with ultrashort echo time (UTE). METHODS A combined strategy was used to accelerate DCE MRI for 3D pulmonary perfusion with whole lung coverage. A highly undersampled 3D radial UTE MRI acquisition was combined with an iterative constrained reconstruction exploiting principal component analysis and wavelet soft-thresholding for dimensionality reduction in space and time. The performance of the method was evaluated using a 3D fractal-based DCE digital lung phantom. Simulated perfusion maps and contrast enhancement curves were compared with ground truth using the structural similarity index (SSIM) to determine robust threshold and regularization levels. Feasibility studies were then performed in a canine and a human subject with 3D radial UTE (TE=0.08 ms) acquisition to assess feasibility of mapping regional 3D perfusion. RESULTS The method was able to accurately recover perfusion maps in the phantom with a nominal isotropic spatial resolution of 1.5 mm (SSIM of 0.949). The canine and human subject studies demonstrated feasibility for providing artifact-free perfusion maps in a simple 3D breath-held acquisition. CONCLUSION The proposed method is promising for fast and flexible 3D pulmonary perfusion imaging. Magn Reson
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Affiliation(s)
- Grzegorz Bauman
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Kevin M. Johnson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Laura C. Bell
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Julia V. Velikina
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Alexey A. Samsonov
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Scott K. Nagle
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Sean B. Fain
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Biomedical Engineering, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
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Bell LC, Johnson KM, Fain SB, Wentland A, Drees R, Johnson RA, Bauman G, Francois CJ, Nagle SK. Simultaneous MRI of lung structure and perfusion in a single breathhold. J Magn Reson Imaging 2013; 41:52-9. [PMID: 24357054 DOI: 10.1002/jmri.24520] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [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: 07/30/2013] [Accepted: 10/31/2013] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To develop and demonstrate a breathheld 3D radial ultrashort echo time (UTE) acquisition to visualize co-registered lung perfusion and vascular structure. MATERIALS AND METHODS Nine healthy dogs were scanned twice at 3 Tesla (T). Contrast-enhanced pulmonary perfusion scans were acquired with a temporally interleaved three-dimensional (3D) radial UTE (TE = 0.08 ms) sequence in a breathhold (1 s time frames over a 33 s breathhold). The 3D breathheld volume was reconstructed into time-resolved perfusion datasets, and a composite vascular structure dataset. For structural comparison, a 5 min respiratory-gated 3D radial UTE scan was acquired. Data were analyzed by quantitative metrics and radiologist scoring. RESULTS Appropriate time-course of contrast was seen in all subjects. Right ventricle to aorta transit times were 7.4 ± 2.0 s. Relative lung enhancement was a factor of 8.4 ± 1.5. Radiologist scoring showed similarly excellent visualization of the pulmonary arteries to the subsegmental level in breathheld (94% of cases) and respiratory-gated (100% of cases) acquisitions (P = 0.33) despite the aggressive under sampling in the breathheld scan. Similarly, differentiation of lung tissue and airways was achieved by both acquisition methods. CONCLUSION A time-resolved 3D radial UTE sequence for simultaneous imaging of pulmonary perfusion and co-registered vascular structure is feasible.
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Affiliation(s)
- Laura C Bell
- School of Medicine and Public Health, Department of Medical Physics, Wisconsin, USA
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Wang K, Schiebler ML, Francois CJ, Del Rio AM, Cornejo MD, Bell LC, Korosec FR, Brittain JH, Holmes JH, Nagle SK. Pulmonary perfusion MRI using interleaved variable density sampling and HighlY constrained cartesian reconstruction (HYCR). J Magn Reson Imaging 2013; 38:751-6. [PMID: 23349079 DOI: 10.1002/jmri.24018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [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: 03/29/2012] [Accepted: 12/05/2012] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To demonstrate the feasibility of performing single breathhold, noncardiac gated, ultrafast, high spatial-temporal resolution whole chest MR pulmonary perfusion imaging in humans. MATERIALS AND METHODS Eight subjects (five male, three female) were scanned with the proposed method on a 3 Tesla clinical scanner using a 32-channel phased-array coil. Seven (88%) were healthy volunteers, and one was a patient volunteer with sarcoidosis. The peak lung enhancement phase for each subject was scored for gravitational effect, peak parenchymal enhancement and severity of artifacts by three cardiothoracic radiologists independently. RESULTS All studies were successfully performed by MR technologists without any additional training. Mean parenchymal signal was very good, measuring 0.78 ± 0.13 (continuous scale, 0 = "none" → 1 = "excellent"). Mean level of motion artifacts was low, measuring 0.13 ± 0.08 (continuous scale, 0 = "none" → 1 = "severe"). CONCLUSION It is feasible to perform single breathhold, noncardiac gated, ultrafast, high spatial-temporal resolution whole chest MR pulmonary perfusion imaging in humans.
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Affiliation(s)
- Kang Wang
- Global Applied Science Laboratory, GE Healthcare, Madison, WI 53705, USA.
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Bell LC, Guengerich FP. Oxidation kinetics of ethanol by human cytochrome P450 2E1. Rate-limiting product release accounts for effects of isotopic hydrogen substitution and cytochrome b5 on steady-state kinetics. J Biol Chem 1997; 272:29643-51. [PMID: 9368031 DOI: 10.1074/jbc.272.47.29643] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A number of cytochrome P450 (P450) 2E1 substrates are known to show kinetic deuterium isotope effects of approximately 5 on Km (DK = DKm/HKm), but not on kcat, in rat liver microsomes (e.g. N-nitrosodimethylamine, ethanol, and CH2Cl2). We observed DKm values of 3-5 for recombinant human P450 2E1-catalyzed ethanol oxidation. Replacing NADPH and O2 with the oxygen surrogate cumene hydroperoxide yielded similar results. Ferric P450 2E1 reduction was fast (k >1000 min-1) even in the absence of substrate. These results indicate that the basis for the increase in Km is in the latter portion of the catalytic cycle. The intrinsic isotope effect (Dk) for ethanol oxidation was determined (competitively) to be 3.8, indicating that C-H bond cleavage is isotopically sensitive. Pre-steady-state studies showed a burst of product formation (k = 410 min-1), with the burst amplitude corresponding to the P450 concentration. Deuteration of ethanol resulted in an isotope effect of 3.2 on the rate of the burst. We conclude that product release is rate-limiting in the oxidation of ethanol to acetaldehyde by P450 2E1. The steady-state kinetics can be described by a paradigm in which the kcat approximates the rate of product release, and Km is an expression in which the denominator is dominated by the rate of C-H bond breaking.
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Affiliation(s)
- L C Bell
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
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Foroozesh M, Primrose G, Guo Z, Bell LC, Alworth WL, Guengerich FP. Aryl acetylenes as mechanism-based inhibitors of cytochrome P450-dependent monooxygenase enzymes. Chem Res Toxicol 1997; 10:91-102. [PMID: 9074808 DOI: 10.1021/tx960064g] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Aryl acetylenes have been investigated as inhibitors of cytochrome P450 (P450)-dependent alkoxyresorufin dealkylation dealkylation activities in liver microsomes prepared from rats exposed to beta-naphthoflavone, isosafrole, or phenobarbital. Many of the acetylenes investigated produce pseudo-first-order time-dependent and NADPH-dependent losses of the dealkylation activities characteristic of mechanism-based irreversible inactivation (suicide inhibition). Replacing the terminal hydrogen of aryl acetylenes with a methyl group to convert ethynes into propynes enhances the inhibition of P450 1A enzymes; in some instances, this modification converts a reversible inhibitor of P450s into a suicide inhibitor. In contrast, ethynes are more effective suicide inhibitors of P450 2B-dependent dealkylations than the corresponding propynes. Aryl acetylenes with an ethynyl group on the 2 position of naphthalene or on the 9 position of phenanthrene and arylalkyl acetylenes with alkyl chains containing 2, 3, or 4 methylene groups are selective inhibitors of P450 2B1/2B2 in liver microsomes from rats. Aryl acetylenes also act as suicide inhibitors of P450 1A2 in human liver microsomes, of purified P450 1A2 from rabbit or rat liver in reconstituted systems, and of purified recombinant human P450 1A2 and 1A1 in reconstituted systems. 4-(1-Propynyl)biphenyl (4PBi) inactivated P450 1A2-dependent ethoxyresourfin deethylation (EROD) activity in human liver microsomes in an NADPH-dependent process (k(inactivation), 0.23 min-1; KI, 2.3 microM). 4PBi also inactivated purified recombinant human P450 1A2 (k(inactivation), 0.24 min-1; KI, 4.3 microM). In agreement with previous reports [Yun, C.-H., Hammons, G. J., Jones, G., Martin, M. V., Hopkins, N. E., Alworth, W. L., and Guengerich, F. P. (1992) Biochemistry 31, 10556-10563], 2-ethynylnaphthalene (2EN) was not a suicide inhibitor of the P450 1A2 activity in human liver microsomes but did inactivate purified human P450 1A2. Neither 4PBi nor 2EN affected diagnostic activities of human microsomal P450 2E1, 2C9/10, 3A4, or 2C19. In the systems examined, the losses of P450-dependent activity produced by these aryl acetylenes were not accompanied by corresponding decreases in the measured P450 absorption spectra. Thus P450 inactivation by these aryl acetylenes does not involve labeling and destruction of the heme. Incubation of 4PBi with microsomal P450 1A1 or 1A2 from rat liver under conditions that lead to P450-dependent, enzyme inactivations generates a 2-biphenylylpropionic acid product. This suggests that the suicide inhibition of P450s by propynylaryl acetylenes proceeds via a methylaryl ketene formed by a 1,2-methyl rearrangement, analogous to the mechanism of suicide inhibition by ethynyl acetylenes that proceed via ketene intermediates formed by 1,2-hydrogen shifts [Ortiz de Montellano, P. R., and Kunze, K. L. (1981) Arch. Biochem. Biophys. 209, 710-712].
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Affiliation(s)
- M Foroozesh
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118-5645, USA
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Dong MS, Bell LC, Guo Z, Phillips DR, Blair IA, Guengerich FP. Identification of retained N-formylmethionine in bacterial recombinant mammalian cytochrome P450 proteins with the N-terminal sequence MALLLAVFL...: roles of residues 3-5 in retention and membrane topology. Biochemistry 1996; 35:10031-40. [PMID: 8756465 DOI: 10.1021/bi960873z] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An N-terminal block to Edman degradation was observed when any of five different mammalian cytochrome P450 (P450) proteins was expressed in Escherichia coli using the N-terminal sequence MALLLAVFL... This block was also seen in Salmonella typhimurium. With all proteins examined, the block could be removed by mild acid hydrolysis (0.6--6 N HCl, 23 degrees C) to expose Met as the N-terminus, suggesting N-formylMet retention. The N-terminal peptide of a modified P450 1A2 ("mutant 1", containing a thrombin-sensitive site inserted at residue 25) was released with thrombin and analyzed by electrospray mass spectrometry and found to yield the M(r) expected for the N-formyl derivative (+/- 0.8 amu). The region of positions 3--5 was altered by random mutagenesis, and three P450 1A2-expressing clones were analyzed for nucleotide and amino acid sequences. The changes from LLL were to RER (P450 1A2a), VDS (P450 1A2b), and WRH (P450 1A2c); these all show slightly dissimilar hydropathy plots compared to the MALLLAVFL... sequence. Mutant P450 1A2a had the N-terminal Met removed to yield N-terminal Ala; P450 1A2b contained an unmodified Met at the N-terminus; P450 1A2c had an approximately 80% block of the N-terminal Met. Experiments with bacterial membranes containing expressed P450 1A2 mutant 1 and P450 1A2 mutant 2 (thrombin-sensitive site inserted at residue 46) suggest that thrombin site 2, but not 1, is sequestered in the membrane. Spheroplasts of bacteria expressing P450 1A2 and the mutants at positions 3--5 were treated with proteinase K; amino acid analysis indicated that no cleavage occurred. These results are interpreted in a model in which most of the mammalian P450 expressed in the bacterium is located in the cytosol, the region near residue 46 is in the inner membrane, the region near residue 25 is in the cytosol, and the N-terminus is either imbedded in the membrane or free in the cytosolic space, depending upon the sequence. However, the possibility that the differences in N-terminal processing are the result of direct changes in interactions with the deformylase and Met aminopeptidase cannot be excluded.
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Affiliation(s)
- M S Dong
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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Yamazaki H, Nakano M, Gillam EM, Bell LC, Guengerich FP, Shimada T. Requirements for cytochrome b5 in the oxidation of 7-ethoxycoumarin, chlorzoxazone, aniline, and N-nitrosodimethylamine by recombinant cytochrome P450 2E1 and by human liver microsomes. Biochem Pharmacol 1996; 52:301-9. [PMID: 8694855 DOI: 10.1016/0006-2952(96)00208-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
NADH-dependent 7-ethoxycoumarin O-deethylation activities could be reconstituted in systems containing cytochrome b5 (b5), NADH-b5 reductase, and bacterial recombinant P450 2E1 in 100 mM potassium phosphate buffer (pH 7.4) containing a synthetic phospholipid mixture and cholate. Replacement of NADH-b5 reductase with NADPH-P450 reductase yielded a 4-fold increase in 7-ethoxycoumarin O-deethylation activity, and further stimulation (approximately 1.5-fold) could be obtained when NADPH was used as an electron donor. Removal of b5 from the NADH- and NADPH-supported systems caused a 90% loss of 7-ethoxycoumarin O-deethylation activities in the presence of NADPH-P450 reductase, but resulted in complete loss of the activities in the absence of NADPH-P450 reductase. Km values were increased and Vmax values were decreased for 7-ethoxycoumarin O-deethylation when b5 was omitted from the NADPH-supported P450 2E1-reconstituted systems. Requirements for b5 in P450 2E1 systems were also observed in chlorzoxazone 6-hydroxylation, aniline p-hydroxylation, and N-nitrosodimethylamine N-demethylation. In human liver microsomes, NADH-dependent 7-ethoxycoumarin O-deethylation, chlorzoxazone 6-hydroxylation, aniline p-hydroxylation, and N-nitrosodimethylamine N-demethylation activities were found to be about 55, 41, 33, and 50%, respectively, of those catalyzed by NADPH-supported systems. Anti-rat NADPH-P450 reductase immunoglobulin G inhibited 7-ethoxycoumarin O-deethylation activity catalyzed by human liver microsomes more strongly in NADPH- than NADH-supported reactions, while anti-human b5 immunoglobulin G inhibited microsomal activities in both NADH- and NADPH-supported systems to similar extents. These results suggest that b5 is an essential component in P450 2E1-catalyzed oxidations of several substrates used, that about 10% of the activities occur via P450 2E1 reduction by NADPH-P450 reductase in the absence of b5, and that the NADH-supported system contributes, in part, to some reactions catalyzed by P450 2E1 in human liver microsomes.
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Affiliation(s)
- H Yamazaki
- Osaka Prefectural Institute of Public Health, Japan
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Nakhgevany R, Bonsu O, Barber J, Mabrouk PA, Ueng YF, Bell LC, Guengerich FP. Preparation, purification, and spectrophotometric characterization of cytochrome P450 1A2 conjugated with polyethylene glycol monomethyl ether. Biochem Biophys Res Commun 1996; 222:406-9. [PMID: 8670218 DOI: 10.1006/bbrc.1996.0757] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Rabbit cytochrome P450 1A2 was modified with succinimidyl carbonate poly(ethylene glycol) monomethyl ether, purified by size exclusion high performance liquid chromatography, and lyophilized. Modification of cytochrome P450 1A2 caused no structural deformation of the heme as evidenced by the similarity of the spectral signatures for both the ferric form and the ferrous-CO complex to the respective forms for the unmodified enzyme. Ethoxyresorufin O-deethylation activity in the presence of iodosobenzene for the modified enzyme was comparable to that of the native enzyme.
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Affiliation(s)
- R Nakhgevany
- Department of Chemistry, Northeastern University, Boston, Massachusetts 02115, USA
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Adams BC, Bell LC, Perfetti CA. A trading relationship between reading skill and domain knowledge in children's text comprehension. Discourse Processes 1995. [DOI: 10.1080/01638539509544943] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
The catalytic mechanism of cytochrome P450 (P450) enzymes has generally been understood in terms of a classic cycle in which electron donation is often limiting and catalysis is understood in terms of hydrogen abstraction and rapid oxygen rebound. In the course of detailed investigations with kinetic hydrogen isotope effects we have studied two systems in which somewhat unusual isotope effects have been interpreted in terms of modifications of the general paradigm. The low isotope effects observed for N-demethylation reactions are in contrast to high values seen with P450-catalyzed C-hydroxylation and peroxidase-catalyzed N-demethylation and are consonant with a role for the P450 FeO2+ entity in base-catalyzed deprotonation of an aminium radical. With P450 2E1, kinetic deuterium isotope effects are seen on the apparent Km for the substrate (increased) but not on Vmax. The results are interpreted in terms of a mechanism where C-H bond cleavage is sensitive to deuterium substitution but a step following this is rate-limiting. This step may be product release.
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Affiliation(s)
- F P Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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Abstract
The oxidation of benzo[a]pyrene (B[a]P) was examined using reconstituted systems prepared with recombinant human cytochrome P450 (P450) enzymes 1A1, 1A2, 2C8, 2C10, 2E1, and 3A4 and with microsomes prepared from Saccharomyces cerevisiae expressing recombinant human P450s 2C8, 2C9, and 2C18. Products measured by HPLC included the 3- and 9-phenols, the 4,5-, 7,8-, and 9,10-dihydrodiols (detected in the presence of epoxide hydrolase), and products in the polar fraction eluting immediately after the void volume. The most active enzyme in all reactions was P450 1A1. P450 3A4 and P450 1A2 formed appreciable amounts of several of the products, including the 3-phenol. P450 2C enzymes and P450 2E1 formed relatively low amounts of all B[a]P products. Consideration of these patterns along with knowledge of levels of expression of the P450s in human tissues and previous results with microsomes leads to the conclusion that P450 1A1 should dominate the oxidation of B[a]P in tissues where it is present and inducible. In human liver the level of P450 1A1 is low and P450 3A4, P450 2C subfamily enzymes, and P450 1A2 probably all contribute. Of the human P450s considered here, P450 1A2 was the most active hepatic enzyme forming the 7,8-dihydrodiol. 7,8-Benzoflavone stimulated the oxidation of B[a]P by P450 3A4 and inhibited the oxidations catalyzed by P450 1A2. The extent of inhibition of P450 1A1 was less (than with P450 1A2), probably due to the rapid oxidation of 7,8-benzoflavone by P450 1A1. The major 7,8-benzoflavone product appears to be the 5,6-oxide.
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Affiliation(s)
- E Bauer
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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Bell LC, Page MD, Berks BC, Richardson DJ, Ferguson SJ. Insertion of transposon Tn5 into a structural gene of the membrane-bound nitrate reductase of Thiosphaera pantotropha results in anaerobic overexpression of periplasmic nitrate reductase activity. J Gen Microbiol 1993; 139:3205-14. [PMID: 8126439 DOI: 10.1099/00221287-139-12-3205] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Chlorate-resistant mutants of the denitrifying bacterium Thiosphaera pantotropha were generated by transposon Tn5 mutagenesis. One class was deficient in membrane-bound nitrate reductase activity but retained a periplasmic nitrate reductase activity. Using transposon marker rescue it was shown that in one such mutant, M-6, the transposon was inserted in the membrane-bound nitrate reductase beta subunit structural gene (termed narH in order to be consistent with the nomenclature of the Escherichia coli major nitrate reductase operon). The translated sequence (total of 106 amino acids) from around the point of transposon insertion showed approximately 90% amino acid identity with the beta subunits of the E. coli nitrate reductases. Under anaerobic growth conditions M-6 overproduced the periplasmic nitrate reductase activity allowing anaerobic growth with nitrate as electron acceptor. A regulatory link was inferred between the presence of the membrane-bound nitrate reductase and expression of the periplasmic nitrate reductase. This is the first demonstration of full denitrification in an organism possessing only a periplasmic nitrate reductase.
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Affiliation(s)
- L C Bell
- Department of Biochemistry, University of Oxford, UK
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Bell LC, Richardson DJ, Ferguson SJ. Identification of nitric oxide reductase activity in Rhodobacter capsulatus: the electron transport pathway can either use or bypass both cytochrome c2 and the cytochrome bc1 complex. J Gen Microbiol 1992; 138:437-43. [PMID: 1317404 DOI: 10.1099/00221287-138-3-437] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Several strains of Rhodobacter capsulatus have been shown to possess a nitric oxide reductase activity (reaction product nitrous oxide) after anaerobic phototrophic growth, but not after aerobic growth. The reductase is associated with the cytoplasmic membrane and electrons can reach the enzyme via the cytochrome bc1 complex. However, use of appropriate strains has shown that neither the latter, cytochrome c2 nor cytochrome c' is essential for the reduction of nitric oxide. Inhibition by myxothiazol of nitric oxide reduction in a strain that lacks a cytochrome c2 establishes that in phototrophically grown R. capsulatus the cytochrome bc1 complex is able to transfer electrons to an acceptor that is alternative to cytochrome c2. Electron transport to nitric oxide from NADH or succinate generated a membrane potential. When isoascorbate plus 2,3,5,6-tetramethyl-p-phenylenediamine (DAD) was the electron donor a membrane potential was not generated. This observation implies that nitric oxide is reduced at the periplasmic surface of the membrane and that the reductase is not proton translocating.
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Affiliation(s)
- L C Bell
- Department of Biochemistry, University of Oxford, UK
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Richardson DJ, Bell LC, McEwan AG, Jackson JB, Ferguson SJ. Cytochrome c2 is essential for electron transfer to nitrous oxide reductase from physiological substrates in Rhodobacter capsulatus and can act as an electron donor to the reductase in vitro. Correlation with photoinhibition studies. Eur J Biochem 1991; 199:677-83. [PMID: 1651241 DOI: 10.1111/j.1432-1033.1991.tb16170.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. Addition of nitrous oxide to a periplasmic fraction released from Rhodobacter capsulatus strains MT1131, N22DNAR+ or AD2 caused oxidation of c-type cytochrome, as judged by the decrease in absorbance at 550 nm. The periplasmic fraction catalysed reduction of nitrous oxide in the presence of either isoascorbate plus phenazine ethosulphate or reduced methyl viologen. The rates with these two electron donors were similar and were comparable to the activity observed with a quantity of cells equivalent to those from which the periplasm sample had been derived. Activity in the periplasm could not be observed with ascorbate plus 2,3,5,6-tetramethyl-p-phenylenediamine although this reductant was effective with intact cells treated with myxothiazol to block the activity of the cytochrome-bc1 complex. 2. Cells of R. capsulatus MTG4/S4, a mutant from which the gene for cytochrome c2 has been specifically deleted, did not catalyse detectable rates of nitrous-oxide reduction. A nitrous-oxide reductase activity was present, as shown by activity of both cells and a periplasmic fraction with isoascorbate plus phenazine ethosulphate as reductant. The rates in cells and the periplasmic fraction were similar to those observed in the corresponding wild-type strain (MT1131). In contrast to wild-type cells, 2,3,5,6-tetramethyl-p-phenylenediamine and N,N,N',N'-tetramethyl-p-phenylenediamine [Ph(NMe2)2] were ineffective as mediators of electrons from isoascorbate. Visible absorption spectra showed that no detectable cytochromes in either the periplasm or intact cells of the MTG4/S4 mutant were oxidised by nitrous oxide. 3. Purified ferroycytochrome c2 from R. capsulatus was oxidised by nitrous oxide in the presence of periplasm from R. capsulatus MTG4/S4. The rate of oxidation was proportional to the amount of periplasm added, but was considerably lower than the rate of nitrous-oxide reduction observed with the same periplasmic fraction when either ascorbate plus phenazine ethosulphate or reduced methyl viologen were used as substrates. The oxidation of cytochrome c2 was inhibited by acetylene and by low concentrations of NaCl. 4. Oxidation of ferrocytochrome c2 by nitrous oxide was observed when the purified cytochrome was mixed with a preparation of nitrous-oxide reductase. However, oxidation of ferrocytochrome c' by nitrous oxide was not observed in the presence of the reductase. The observations with the mutant MTG4/S4 suggest that cytochrome c2 is the only periplasmic cytochrome involved in nitrous-oxide reduction. 5. Nitrous-oxide-dependent oxidation of a c-type cytochrome was observed in a periplasmic fraction from Paracoccus denitrificans, provided the fraction was first reduced.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- D J Richardson
- School of Biochemistry, University of Birmingham, England
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Abstract
Use of Clark-type electrodes has shown that, in cells of Thiosphaera pantotropha, the nitrous oxide reductase is active in the presence of O2, and that the two gases involved (N2O, O2) are reduced simultaneously, but with mutual inhibition. Reduction of nitrate, or nitrite, to N2O under aerobic conditions involves NO as an intermediate, as judged by trapping experiments with the ferric form of extracellular horse heart cytochrome c and the demonstration that the cells possess a nitric oxide reductase activity. The overall conversion of nitrate to N2, the process of denitrification, under aerobic conditions, is thus not prevented by reaction of NO with O2 and depends upon a nitrous oxide reductase system which differs from that in other organisms by being neither directly inhibited nor inactivated by O2.
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Affiliation(s)
- L C Bell
- Department of Biochemistry, University of Oxford, U.K
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Bell LC, Richardson DJ, Ferguson SJ. Periplasmic and membrane-bound respiratory nitrate reductases in Thiosphaera pantotropha. The periplasmic enzyme catalyzes the first step in aerobic denitrification. FEBS Lett 1990; 265:85-7. [PMID: 2365057 DOI: 10.1016/0014-5793(90)80889-q] [Citation(s) in RCA: 167] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The unusual ability of Thiosphaera pantotropha to catalyze respiratory nitrate reduction under aerobic conditions is shown to correlate with the activity of a periplasmic nitrate reductase that is expressed under both aerobic and anaerobic growth conditions. The organism also synthesizes, but only under anaerobic conditions, a membrane-bound nitrate reductase which resembles the corresponding enzyme in Paracoccus denitrificans in respect of both catalytic properties and inhibition of activity in intact cells in the presence of oxygen.
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Affiliation(s)
- L C Bell
- Department of Biochemistry, University of Oxford, UK
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Page MD, Carr G, Bell LC, Ferguson SJ. Structure, control and assembly of a bacterial electron transport system as exemplified by Paracoccus denitrificans. Biochem Soc Trans 1989; 17:991-3. [PMID: 2697623 DOI: 10.1042/bst0170991] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M D Page
- Department of Biochemistry, University of Oxford, U.K
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Bruce RC, Warrell LA, Edwards DG, Bell LC. Effects of aluminium and calcium in the soil solution of acid soils on root elongation of Glycine max cv. Forrest. ACTA ACUST UNITED AC 1988. [DOI: 10.1071/ar9880319] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In the course of three experiments, soybean (Glycerine max (L.) Merr.) cv. Forrest was grown in 21 soils (four surface soils and 17 subsoils) amended with liming materials (CaCO3 and Mg CO3) and soluble Ca salts (CaSO4.2H20 and CaCl2.2H2O). In most soils, the soluble salts increased concentrations and activities of Al species in solution to levels that restricted root growth, and MgCO3, induced a Ca limitation to root growth. Root lengths after three days were related to so11 and soil solution attributes.Suitable diagnostic indices for the prediction of Ca limitations to root growth were either Ca saturation of the effective cation exchange capacity or Ca activity ratio of the soil solution, which was defined as the ratio of the activity of Ca to the sum of the activities of Ca, Mg, Na, and K. Values corresponding to 90% relative root length (RRL) of soybean were 0.05 for the Ca activity ratio and 11% for Ca saturation. Calcium activity and Ca concentration in the soil solution and exchangeable Ca were less useful for this purpose.Soil Al saturation was not a good predictor of Al toxicity, but soil solution measurements were. The activities of Al3+ and AlOH2+ gave the best associations with RRL, and values corresponding to 90% RRL were 4 8M and 0.5 8M respectively. The results suggested that Al(OH)3� , Al(OH)2+, and AlSO4+, were not toxic species. Soil solution pH and soil pH measured in water were more sensitive indicators of root growth than soil pH measured in 0.01 M CaCl2.Using a Ca activity ratio of 0.05 and an Al3+ activity of 4 8M as diagnostic indices, none of the 20 soils in two experiments were toxic in Al, while 13 (all subsoils) were deficient in Ca. Thus the first limitation on root growth was Ca deficiency and not Al toxicity, in spite of high Al saturations and relatively low pH in these soils. However, Al toxicity could be induced by increasing the ionic strengths of soil solutions.
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Abstract
A pot experiment in which wheat cv. Timgalen was grown in a glasshouse for 6 weeks clearly established that some of the 12 Darling Downs black earths investigated were zinc deficient. Rates of application between 1.2 and 3.7 kg zinc ha-1 (as ZnSO4.7H2O) were sufficient to achieve maximum or near-maximum dry matter yield of tops on the deficient soils. Plant zinc concentration and total zinc uptake in the tops increased in all soils with increasing rates of zinc application. The critical zinc concentration in the wheat tops associated with 90% of maximum dry matter yield was 20 �g g-1. Three extraction methods were used to determine the initial available zinc status of the soils. All methods gave lower extractable zinc values in the acid (pH <7 . 0 in 0.01 M calcium chloride) black earths (Mywybilla soils) than in the alkaline black earths. Critical extractable zinc values were much lower in the acid black earths. EDTA-ammonium carbonate (pH 8.6) more effectively separated zinc-deficient and marginally deficient from adequately supplied alkaline black earths than either EDTA-ammonium acetate (pH 7.0) or DTPA (pH 7.3). The critical extractable zinc value for the alkaline black earths with EDTA-ammonium carbonate was 0.61 �g g-1.
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Abstract
In the absence of chemical limitations, the emergence and yield of Rhodes grass (Chloris gayana) on a 20 per cent fly ash : 80 per cent red sand mix were higher than those on fly ash or red sand alone or on the other mixes investigated. The poor emergence and yield in the red sand was attributed to the medium's low available water capacity and low unsaturated hydraulic conductivity. Mixtures containing from 40 per cent to 100 per cent fly ash were characterized by very low air contents at field capacity and were susceptible to water-logging. The extremely poor emergence and low yields observed in the mixtures containing 40 per cent and 60 per cent fly ash were considered to be due to high mechanical resistance to root ramification in addition to lack of aeration. In the absence of the limitations of excess salinity, alkalinity and sodicity, deficiencies of nitrogen and phosphorus were the major restrictions to the growth of Rhodes grass on fly ash, red sand and a 20 per cent fly ash : 80 per cent red sand mix. Manganese was also limiting in red sand, and boron was slightly deficient in fly ash, but these deficiencies were not present in the ash : sand mix. In a nitrogen (NH4NO3) by phosphorus (Ca(H2PO4)2.H2O) interaction trial on fly ash and red sand, maximum yields of Rhodes grass were obtained with 100 kg N ha-1 (red sand) to 200 kg N ha-1 (fly ash) and 400 kg P ha-1. The severe yield depression which occurred at nitrogen rates greater than 200 kg ha-1 on both wastes was attributed to NH4+ toxicity aggravated by the dearth of nitrifying bacteria and the wastes' low cation exchange capacities.
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Abstract
Excess soluble salts (EC 30 to 48 mScm-1), high alkalinity (pH 9.2 to 11 .0) and potentially toxic levels of sodium (ESP 49 to 88 per cent) were characteristic of fly ash and bauxite wastes ('red sand' and 'red mud') from the Gladstone alumina refinery. In red sand, N and P levels were extremely low and Zn and Mn marginal; extremely low levels of N and P and a marginal amount of Zn were measured in the red mud. Fly ash was characterized by a potentially toxic level of B and deficiency levels of N and Zn. The physical limitations of low water holding capacity of red sand and the susceptibility of fly ash to wind erosion were reduced by mixing the wastes. Excess soluble salts in fly ash-red sand mixtures were effectively removed by leaching without an accompanying decrease in the saturated hydraulic conductivities of the solids. Following the reduction in salinity, the pH values of the wastes remained high (8.4 to 9.6). Incubation of the ash and sand with NH4NO3, superphosphate, FeSO4.7H2O, FeS2 and S for up to ten weeks demonstrated that FeSO4.7H20 was the most effective acidulant in the short term. Reduction of the excessive exchangeable sodium percentages in ash (49 per cent) and sand (88 per cent) to levels tolerable to plant growth was achieved by leaching and acidification.
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