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Giri T, Maloney SE, Giri S, Goo YA, Song JH, Son M, Tycksen E, Conyers SB, Bice A, Ge X, Garbow JR, Quirk JD, Bauer AQ, Palanisamy A. Oxytocin-induced birth causes sex-specific behavioral and brain connectivity changes in developing rat offspring. iScience 2024; 27:108960. [PMID: 38327784 PMCID: PMC10847747 DOI: 10.1016/j.isci.2024.108960] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/23/2023] [Accepted: 01/15/2024] [Indexed: 02/09/2024] Open
Abstract
Despite six decades of the use of exogenous oxytocin for management of labor, little is known about its effects on the developing brain. Motivated by controversial reports suggesting a link between oxytocin use during labor and autism spectrum disorders (ASDs), we employed our recently validated rat model for labor induction with oxytocin to address this important concern. Using a combination of molecular biological, behavioral, and neuroimaging assays, we show that induced birth with oxytocin leads to sex-specific disruption of oxytocinergic signaling in the developing brain, decreased communicative ability of pups, reduced empathy-like behaviors especially in male offspring, and widespread sex-dependent changes in functional cortical connectivity. Contrary to our hypothesis, social behavior, typically impaired in ASDs, was largely preserved. Collectively, our foundational studies provide nuanced insights into the neurodevelopmental impact of birth induction with oxytocin and set the stage for mechanistic investigations in animal models and prospective longitudinal clinical studies.
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Affiliation(s)
- Tusar Giri
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Susan E. Maloney
- Department of Psychiatry, Intellectual and Developmental Disabilities Research Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Saswat Giri
- Graduate Student, School of Public Health and Social Justice, St. Louis University, St. Louis, MO, USA
| | - Young Ah Goo
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Mass Spectrometry Technology Access Center (MTAC), McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Jong Hee Song
- Mass Spectrometry Technology Access Center (MTAC), McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Minsoo Son
- Mass Spectrometry Technology Access Center (MTAC), McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Eric Tycksen
- Genome Technology Access Center (GTAC), McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Sara B. Conyers
- Department of Psychiatry, Intellectual and Developmental Disabilities Research Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Annie Bice
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Xia Ge
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Joel R. Garbow
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - James D. Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Adam Q. Bauer
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Arvind Palanisamy
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO, USA
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2
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Moore SM, Quirk JD, Lassiter AW, Laforest R, Ayers GD, Badea CT, Fedorov AY, Kinahan PE, Holbrook M, Larson PEZ, Sriram R, Chenevert TL, Malyarenko D, Kurhanewicz J, Houghton AM, Ross BD, Pickup S, Gee JC, Zhou R, Gammon ST, Manning HC, Roudi R, Daldrup-Link HE, Lewis MT, Rubin DL, Yankeelov TE, Shoghi KI. Co-Clinical Imaging Metadata Information (CIMI) for Cancer Research to Promote Open Science, Standardization, and Reproducibility in Preclinical Imaging. Tomography 2023; 9:995-1009. [PMID: 37218941 DOI: 10.3390/tomography9030081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 04/30/2023] [Accepted: 05/04/2023] [Indexed: 05/24/2023] Open
Abstract
Preclinical imaging is a critical component in translational research with significant complexities in workflow and site differences in deployment. Importantly, the National Cancer Institute's (NCI) precision medicine initiative emphasizes the use of translational co-clinical oncology models to address the biological and molecular bases of cancer prevention and treatment. The use of oncology models, such as patient-derived tumor xenografts (PDX) and genetically engineered mouse models (GEMMs), has ushered in an era of co-clinical trials by which preclinical studies can inform clinical trials and protocols, thus bridging the translational divide in cancer research. Similarly, preclinical imaging fills a translational gap as an enabling technology for translational imaging research. Unlike clinical imaging, where equipment manufacturers strive to meet standards in practice at clinical sites, standards are neither fully developed nor implemented in preclinical imaging. This fundamentally limits the collection and reporting of metadata to qualify preclinical imaging studies, thereby hindering open science and impacting the reproducibility of co-clinical imaging research. To begin to address these issues, the NCI co-clinical imaging research program (CIRP) conducted a survey to identify metadata requirements for reproducible quantitative co-clinical imaging. The enclosed consensus-based report summarizes co-clinical imaging metadata information (CIMI) to support quantitative co-clinical imaging research with broad implications for capturing co-clinical data, enabling interoperability and data sharing, as well as potentially leading to updates to the preclinical Digital Imaging and Communications in Medicine (DICOM) standard.
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Affiliation(s)
- Stephen M Moore
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Andrew W Lassiter
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Richard Laforest
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gregory D Ayers
- Department of Biostatistics, Vanderbilt University, Nashville, TN 37235, USA
| | - Cristian T Badea
- Quantitative Imaging and Analysis Lab, Department of Radiology, Duke University, Durham, NC 27708, USA
| | - Andriy Y Fedorov
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Paul E Kinahan
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Matthew Holbrook
- Quantitative Imaging and Analysis Lab, Department of Radiology, Duke University, Durham, NC 27708, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| | - Renuka Sriram
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| | - Thomas L Chenevert
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Dariya Malyarenko
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| | | | - Brian D Ross
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Stephen Pickup
- Department of Radiology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - James C Gee
- Department of Radiology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rong Zhou
- Department of Radiology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Seth T Gammon
- Department of Cancer Systems Imaging, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Henry Charles Manning
- Department of Cancer Systems Imaging, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Raheleh Roudi
- Department of Radiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Heike E Daldrup-Link
- Department of Radiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Michael T Lewis
- Dan L Duncan Comprehensive Cancer Center, Departments of Molecular and Cellular Biology and Radiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Daniel L Rubin
- Departments of Biomedical Data Science, Radiology and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Thomas E Yankeelov
- Departments of Biomedical Engineering, Diagnostic Medicine and Oncology, Oden Institute for Computational and Engineering Sciences, Livestrong Cancer Institutes, The University of Texas at Austin, Austin, TX 78712, USA
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kooresh I Shoghi
- Mallinckrodt Institute of Radiology, Department of Biomedical Engineering, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63110, USA
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3
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Gammon ST, Cohen AS, Lehnert AL, Sullivan DC, Malyarenko D, Manning HC, Hormuth DA, Daldrup-Link HE, An H, Quirk JD, Shoghi K, Pagel MD, Kinahan PE, Miyaoka RS, Houghton AM, Lewis MT, Larson P, Sriram R, Blocker SJ, Pickup S, Badea A, Badea CT, Yankeelov TE, Chenevert TL. An Online Repository for Pre-Clinical Imaging Protocols (PIPs). Tomography 2023; 9:750-758. [PMID: 37104131 PMCID: PMC10145184 DOI: 10.3390/tomography9020060] [Citation(s) in RCA: 0] [Impact Index Per Article: 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] [Received: 01/14/2023] [Revised: 03/15/2023] [Accepted: 03/16/2023] [Indexed: 03/29/2023] Open
Abstract
Providing method descriptions that are more detailed than currently available in typical peer reviewed journals has been identified as an actionable area for improvement. In the biochemical and cell biology space, this need has been met through the creation of new journals focused on detailed protocols and materials sourcing. However, this format is not well suited for capturing instrument validation, detailed imaging protocols, and extensive statistical analysis. Furthermore, the need for additional information must be counterbalanced by the additional time burden placed upon researchers who may be already overtasked. To address these competing issues, this white paper describes protocol templates for positron emission tomography (PET), X-ray computed tomography (CT), and magnetic resonance imaging (MRI) that can be leveraged by the broad community of quantitative imaging experts to write and self-publish protocols in protocols.io. Similar to the Structured Transparent Accessible Reproducible (STAR) or Journal of Visualized Experiments (JoVE) articles, authors are encouraged to publish peer reviewed papers and then to submit more detailed experimental protocols using this template to the online resource. Such protocols should be easy to use, readily accessible, readily searchable, considered open access, enable community feedback, editable, and citable by the author.
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Affiliation(s)
- Seth T. Gammon
- Department of Cancer Systems Imaging, University of MD Anderson Cancer Center, 1881 E. Road, Houston, TX 77030, USA
- Correspondence: ; Tel.: +713-745-3705
| | - Allison S. Cohen
- Department of Cancer Systems Imaging, University of MD Anderson Cancer Center, 1881 E. Road, Houston, TX 77030, USA
| | | | - Daniel C. Sullivan
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Dariya Malyarenko
- Department of Radiology, University of Michigan, Ann Arbor, MI 48108, USA
| | - Henry Charles Manning
- Department of Cancer Systems Imaging, University of MD Anderson Cancer Center, 1881 E. Road, Houston, TX 77030, USA
| | - David A. Hormuth
- Oden Institute for Computational Engineering and Sciences, and Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Heike E. Daldrup-Link
- Department of Radiology, Molecular Imaging Program at Stanford, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Hongyu An
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
| | - James D. Quirk
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
| | - Kooresh Shoghi
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
| | - Mark David Pagel
- Department of Cancer Systems Imaging, University of MD Anderson Cancer Center, 1881 E. Road, Houston, TX 77030, USA
| | - Paul E. Kinahan
- Department of Radiology, University of Washington, Seattle, WA 98105, USA
| | - Robert S. Miyaoka
- Department of Radiology, University of Washington, Seattle, WA 98105, USA
| | | | - Michael T. Lewis
- Lester and Sue Smith Breast Center, Dan L Duncan Comprehensive Cancer Center, Houston, TX 77030, USA
| | - Peder Larson
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Renuka Sriram
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Stephanie J. Blocker
- Center for In Vivo Microscopy, Department of Radiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Stephen Pickup
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alexandra Badea
- Department of Radiology, Duke University, Durham, NC 27708, USA
| | | | - Thomas E. Yankeelov
- Department of Biomedical Engineering, Diagnostic Medicine, and Oncology, Oden Institute for Computational Engineering and Sciences, Livestrong Cancer Institutes, The University of Texas at Austin, Austin, TX 78712, USA
- Department of Imaging Physics, MD Anderson Cancer Center, Houston, TX 77030, USA
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4
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Zhou Q, Quirk JD, Hu Y, Yan H, Gaut JP, Pham CTN, Wickline SA, Pan H. Rapamycin Perfluorocarbon Nanoparticle Mitigates Cisplatin-Induced Acute Kidney Injury. Int J Mol Sci 2023; 24:6086. [PMID: 37047059 PMCID: PMC10093942 DOI: 10.3390/ijms24076086] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [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: 02/17/2023] [Revised: 03/16/2023] [Accepted: 03/21/2023] [Indexed: 04/14/2023] Open
Abstract
For nearly five decades, cisplatin has played an important role as a standard chemotherapeutic agent and been prescribed to 10-20% of all cancer patients. Although nephrotoxicity associated with platinum-based agents is well recognized, treatment of cisplatin-induced acute kidney injury is mainly supportive and no specific mechanism-based prophylactic approach is available to date. Here, we postulated that systemically delivered rapamycin perfluorocarbon nanoparticles (PFC NP) could reach the injured kidneys at sufficient and sustained concentrations to mitigate cisplatin-induced acute kidney injury and preserve renal function. Using fluorescence microscopic imaging and fluorine magnetic resonance imaging/spectroscopy, we illustrated that rapamycin-loaded PFC NP permeated and were retained in injured kidneys. Histologic evaluation and blood urea nitrogen (BUN) confirmed that renal structure and function were preserved 48 h after cisplatin injury. Similarly, weight loss was slowed down. Using western blotting and immunofluorescence staining, mechanistic studies revealed that rapamycin PFC NP significantly enhanced autophagy in the kidney, reduced the expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), as well as decreased the expression of the apoptotic protein Bax, all of which contributed to the suppression of apoptosis that was confirmed with TUNEL staining. In summary, the delivery of an approved agent such as rapamycin in a PFC NP format enhances local delivery and offers a novel mechanism-based prophylactic therapy for cisplatin-induced acute kidney injury.
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Affiliation(s)
- Qingyu Zhou
- Taneja College of Pharmacy, University of South Florida, Tampa, FL 33620, USA
| | - James D. Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ying Hu
- Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Huimin Yan
- Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Joseph P. Gaut
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Christine T. N. Pham
- Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Samuel A. Wickline
- Morsani College of Medicine, University of South Florida, Tampa, FL 33620, USA
| | - Hua Pan
- Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
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5
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Malyarenko D, Amouzandeh G, Pickup S, Zhou R, Manning HC, Gammon ST, Shoghi KI, Quirk JD, Sriram R, Larson P, Lewis MT, Pautler RG, Kinahan PE, Muzi M, Chenevert TL. Evaluation of Apparent Diffusion Coefficient Repeatability and Reproducibility for Preclinical MRIs Using Standardized Procedures and a Diffusion-Weighted Imaging Phantom. Tomography 2023; 9:375-386. [PMID: 36828382 PMCID: PMC9964373 DOI: 10.3390/tomography9010030] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
Relevant to co-clinical trials, the goal of this work was to assess repeatability, reproducibility, and bias of the apparent diffusion coefficient (ADC) for preclinical MRIs using standardized procedures for comparison to performance of clinical MRIs. A temperature-controlled phantom provided an absolute reference standard to measure spatial uniformity of these performance metrics. Seven institutions participated in the study, wherein diffusion-weighted imaging (DWI) data were acquired over multiple days on 10 preclinical scanners, from 3 vendors, at 6 field strengths. Centralized versus site-based analysis was compared to illustrate incremental variance due to processing workflow. At magnet isocenter, short-term (intra-exam) and long-term (multiday) repeatability were excellent at within-system coefficient of variance, wCV [±CI] = 0.73% [0.54%, 1.12%] and 1.26% [0.94%, 1.89%], respectively. The cross-system reproducibility coefficient, RDC [±CI] = 0.188 [0.129, 0.343] µm2/ms, corresponded to 17% [12%, 31%] relative to the reference standard. Absolute bias at isocenter was low (within 4%) for 8 of 10 systems, whereas two high-bias (>10%) scanners were primary contributors to the relatively high RDC. Significant additional variance (>2%) due to site-specific analysis was observed for 2 of 10 systems. Base-level technical bias, repeatability, reproducibility, and spatial uniformity patterns were consistent with human MRIs (scaled for bore size). Well-calibrated preclinical MRI systems are capable of highly repeatable and reproducible ADC measurements.
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Affiliation(s)
- Dariya Malyarenko
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ghoncheh Amouzandeh
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109, USA
- Neuro42, Inc., San Francisco, CA 94105, USA
| | - Stephen Pickup
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rong Zhou
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Henry Charles Manning
- Department of Cancer Systems Imaging, The University of Texas MDACC, Houston, TX 77030, USA
| | - Seth T. Gammon
- Department of Cancer Systems Imaging, The University of Texas MDACC, Houston, TX 77030, USA
| | - Kooresh I. Shoghi
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James D. Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Renuka Sriram
- UCSF Department of Radiology & Biomedical Imaging, San Francisco, CA 94158, USA
| | - Peder Larson
- UCSF Department of Radiology & Biomedical Imaging, San Francisco, CA 94158, USA
| | | | | | - Paul E. Kinahan
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Mark Muzi
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
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Pan S, Yang PH, DeFreitas D, Ramagiri S, Bayguinov PO, Hacker CD, Snyder AZ, Wilborn J, Huang H, Koller GM, Raval DK, Halupnik GL, Sviben S, Achilefu S, Tang R, Haller G, Quirk JD, Fitzpatrick JAJ, Esakky P, Strahle JM. Gold nanoparticle-enhanced X-ray microtomography of the rodent reveals region-specific cerebrospinal fluid circulation in the brain. Nat Commun 2023; 14:453. [PMID: 36707519 PMCID: PMC9883388 DOI: 10.1038/s41467-023-36083-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/12/2023] [Indexed: 01/28/2023] Open
Abstract
Cerebrospinal fluid (CSF) is essential for the development and function of the central nervous system (CNS). However, the brain and its interstitium have largely been thought of as a single entity through which CSF circulates, and it is not known whether specific cell populations within the CNS preferentially interact with the CSF. Here, we develop a technique for CSF tracking, gold nanoparticle-enhanced X-ray microtomography, to achieve micrometer-scale resolution visualization of CSF circulation patterns during development. Using this method and subsequent histological analysis in rodents, we identify previously uncharacterized CSF pathways from the subarachnoid space (particularly the basal cisterns) that mediate CSF-parenchymal interactions involving 24 functional-anatomic cell groupings in the brain and spinal cord. CSF distribution to these areas is largely restricted to early development and is altered in posthemorrhagic hydrocephalus. Our study also presents particle size-dependent CSF circulation patterns through the CNS including interaction between neurons and small CSF tracers, but not large CSF tracers. These findings have implications for understanding the biological basis of normal brain development and the pathogenesis of a broad range of disease states, including hydrocephalus.
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Affiliation(s)
- Shelei Pan
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Peter H Yang
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Dakota DeFreitas
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sruthi Ramagiri
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Peter O Bayguinov
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Carl D Hacker
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Abraham Z Snyder
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neurology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Jackson Wilborn
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Hengbo Huang
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Gretchen M Koller
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Dhvanii K Raval
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Grace L Halupnik
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sanja Sviben
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Samuel Achilefu
- Department of Biomedical Engineering, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Rui Tang
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Gabriel Haller
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neurology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - James D Quirk
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - James A J Fitzpatrick
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neuroscience, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Cell Biology and Physiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Prabagaran Esakky
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Jennifer M Strahle
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
- Department of Orthopedic Surgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
- Department of Pediatrics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
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7
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Devan SP, Jiang X, Luo G, Xie J, Quirk JD, Engelbach JA, Harmsen H, McKinley ET, Cui J, Zu Z, Attia A, Garbow JR, Gore JC, McKnight CD, Kirschner AN, Xu J. Selective Cell Size MRI Differentiates Brain Tumors from Radiation Necrosis. Cancer Res 2022; 82:3603-3613. [PMID: 35877201 PMCID: PMC9532360 DOI: 10.1158/0008-5472.can-21-2929] [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: 08/30/2021] [Revised: 02/05/2022] [Accepted: 07/21/2022] [Indexed: 11/16/2022]
Abstract
Brain metastasis is a common characteristic of late-stage lung cancers. High doses of targeted radiotherapy can control tumor growth in the brain but can also result in radiotherapy-induced necrosis. Current methods are limited for distinguishing whether new parenchymal lesions following radiotherapy are recurrent tumors or radiotherapy-induced necrosis, but the clinical management of these two classes of lesions differs significantly. Here, we developed, validated, and evaluated a new MRI technique termed selective size imaging using filters via diffusion times (SSIFT) to differentiate brain tumors from radiotherapy necrosis in the brain. This approach generates a signal filter that leverages diffusion time dependence to establish a cell size-weighted map. Computer simulations in silico, cultured cancer cells in vitro, and animals with brain tumors in vivo were used to comprehensively validate the specificity of SSIFT for detecting typical large cancer cells and the ability to differentiate brain tumors from radiotherapy necrosis. SSIFT was also implemented in patients with metastatic brain cancer and radiotherapy necrosis. SSIFT showed high correlation with mean cell sizes in the relevant range of less than 20 μm. The specificity of SSIFT for brain tumors and reduced contrast in other brain etiologies allowed SSIFT to differentiate brain tumors from peritumoral edema and radiotherapy necrosis. In conclusion, this new, cell size-based MRI method provides a unique contrast to differentiate brain tumors from other pathologies in the brain. SIGNIFICANCE This work introduces and provides preclinical validation of a new diffusion MRI method that exploits intrinsic differences in cell sizes to distinguish brain tumors and radiotherapy necrosis.
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Affiliation(s)
- Sean P Devan
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, TN, 37232, USA
| | - Xiaoyu Jiang
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Guozhen Luo
- Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jingping Xie
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
| | - John A Engelbach
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
| | - Hannah Harmsen
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Eliot T McKinley
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Jing Cui
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Zhongliang Zu
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Albert Attia
- Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Joel R Garbow
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110, USA
- Alvin J Siteman Cancer Center, Washington University, St. Louis, MO, 63110, USA
| | - John C. Gore
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37232, USA
| | - Colin D McKnight
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Austin N Kirschner
- Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Junzhong Xu
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37232, USA
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8
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Fang L, Huang H, Quirk JD, Zheng J, Shen D, Manion B, Mixdorf M, Karmakar P, Sudlow GP, Tang R, Achilefu S. Analysis of Stable Chelate-free Gadolinium Loaded Titanium Dioxide Nanoparticles for MRI-Guided Radionuclide Stimulated Cancer Treatment. CURR ANAL CHEM 2022; 18:826-835. [PMID: 36561765 PMCID: PMC9770661 DOI: 10.2174/1573411018666220321102736] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background Recent studies demonstrate that titanium dioxide nanoparticles (TiO2 NPs) are an effective source of reactive oxygen species (ROS) for photodynamic therapy and radionuclide stimulated dynamic therapy (RaST). Unfortunately tracking the in vivo distribution of TiO2 NPs noninvasively remains elusive. Objective Given the use of gadolinium (Gd) chelates as effective contrast agents for magnetic resonance imaging (MRI), this study aims to (1) develop hybrid TiO2-Gd NPs that exhibit high relaxivity for tracking the NPs without loss of ROS generating capacity; and (2) establish a simple colorimetric assay for quantifying Gd loading and stability. Methods A chelate-free, heat-induced method was used to load Gd onto TiO2 NPs, which was coated with transferrin (Tf). A sensitive colorimetric assay and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine Gd loading and stability of the TiO2-Gd-Tf NPs. Measurement of the relaxivity was performed on a 1.4 T relaxometer and a 4.7 T small animal magnetic resonance scanner to estimate the effects of magnetic field strength. ROS was quantified by activated dichlorodihydrofluorescein diacetate fluorescence. Cell uptake of the NPs and RaST were monitored by fluorescence microscopy. Both 3 T and 4.7 T scanners were used to image the in vivo distribution of intravenously injected NPs in tumor-bearing mice. Results A simple colorimetric assay accurately determined both the loading and stability of the NPs compared with the expensive and complex ICP-MS method. Coating of the TiO2-Gd NPs with Tf stabilized the nanoconstruct and minimized aggregation. The TiO2-Gd-Tf maintained ROS-generating capability without inducing cell death at a wide range of concentrations but induced significant cell death under RaST conditions in the presence of F-18 radiolabeled 2-fluorodeoxyglucose. The longitudinal (r1 = 10.43 mM-1s-1) and transverse (r2 = 13.43 mM-1s-1) relaxivity of TiO2-Gd-Tf NPs were about twice and thrice, respectively, those of clinically used Gd contrast agent (Gd-DTPA; r1 = 3.77 mM-1s-1 and r2 = 5.51 mM-1s-1) at 1.4 T. While the r1 (8.13 mM-1s-1) reduced to about twice that of Gd-DTPA (4.89 mM-1s-1) at 4.7 T, the corresponding r2 (87.15 mM-1s-1) increased by a factor 22.6 compared to Gd-DTPA (r2 = 3.85). MRI of tumor-bearing mice injected with TiO2-Gd-Tf NPs tracked the NPs distribution and accumulation in tumors. Conclusion This work demonstrates that Arsenazo III colorimetric assay can substitute ICP-MS for determining the loading and stability of Gd-doped TiO2 NPs. The new nanoconstruct enabled RaST effect in cells, exhibited high relaxivity, and enhanced MRI contrast in tumors in vivo, paving the way for in vivo MRI-guided RaST.
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Affiliation(s)
- Lei Fang
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States,Department of Biomedical Engineering, School of Engineering, Washington University in St. Louis, Saint Louis, United States
| | - Hengbo Huang
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States,Department of Biomedical Engineering, School of Engineering, Washington University in St. Louis, Saint Louis, United States
| | - James D. Quirk
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Jie Zheng
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Duanwen Shen
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Brad Manion
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Matthew Mixdorf
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Partha Karmakar
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Gail P. Sudlow
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Rui Tang
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States
| | - Samuel Achilefu
- School of Medicine, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Saint Louis, United States,Department of Biomedical Engineering, School of Engineering, Washington University in St. Louis, Saint Louis, United States,Department of Biochemistry and Molecular Biophysics, School of Medicine, Washington University in St. Louis, Saint Louis, United States,Department of Biomedical Engineering, University of Texas Southwestern, Dallas, United States,Address correspondence to this author at the Department of Biomedical Engineering, School of Engineering, Washington University in St. Louis, Saint Louis, United States;
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9
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Bazzi MS, Balouchzadeh R, Pavey SN, Quirk JD, Yanagisawa H, Vedula V, Wagenseil JE, Barocas VH. Experimental and Mouse-Specific Computational Models of the Fbln4 SMKO Mouse to Identify Potential Biomarkers for Ascending Thoracic Aortic Aneurysm. Cardiovasc Eng Technol 2022; 13:558-572. [PMID: 35064559 PMCID: PMC9304450 DOI: 10.1007/s13239-021-00600-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/28/2021] [Indexed: 11/02/2022]
Abstract
PURPOSE To use computational methods to explore geometric, mechanical, and fluidic biomarkers that could correlate with mouse lifespan in the Fbln4SMKO mouse. Mouse lifespan was used as a surrogate for risk of a severe cardiovascular event in cases of ascending thoracic aortic aneurysm. METHODS Image-based, mouse-specific fluid-structure-interaction models were developed for Fbln4SMKO mice (n = 10) at ages two and six months. The results of the simulations were used to quantify potential biofluidic biomarkers, complementing the geometrical biomarkers obtained directly from the images. RESULTS Comparing the different geometrical and biofluidic biomarkers to the mouse lifespan, it was found that mean oscillatory shear index (OSImin) and minimum time-averaged wall shear stress (TAWSSmin) at six months showed the largest correlation with lifespan (r2 = 0.70, 0.56), with both correlations being positive (i.e., mice with high OSImean and high TAWSSmin tended to live longer). When change between two and six months was considered, the change in TAWSSmin showed a much stronger correlation than OSImean (r2 = 0.75 vs. 0.24), and the correlation was negative (i.e., mice with increasing TAWSSmin over this period tended to live less long). CONCLUSION The results highlight potential biomarkers of ATAA outcomes that can be obtained through noninvasive imaging and computational simulations, and they illustrate the potential synergy between small-animal and computational models.
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Affiliation(s)
- Marisa S Bazzi
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Ramin Balouchzadeh
- Department of Mechanical Engineering & Materials Science, Washington University, St. Louis, MO, 63110, USA
| | - Shawn N Pavey
- Department of Mechanical Engineering & Materials Science, Washington University, St. Louis, MO, 63110, USA
| | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Hiromi Yanagisawa
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Japan
| | - Vijay Vedula
- Department of Mechanical Engineering, Columbia University, New York, NY, 10027, USA
| | - Jessica E Wagenseil
- Department of Mechanical Engineering & Materials Science, Washington University, St. Louis, MO, 63110, USA
| | - Victor H Barocas
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, 55455, USA.
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10
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Niedbalski PJ, Cochran AS, Freeman MS, Guo J, Fugate EM, Davis CB, Dahlke J, Quirk JD, Varisco BM, Woods JC, Cleveland ZI. Validating in vivo hyperpolarized 129 Xe diffusion MRI and diffusion morphometry in the mouse lung. Magn Reson Med 2021; 85:2160-2173. [PMID: 33017076 PMCID: PMC8544163 DOI: 10.1002/mrm.28539] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/27/2020] [Accepted: 09/14/2020] [Indexed: 02/03/2023]
Abstract
PURPOSE Diffusion and lung morphometry imaging using hyperpolarized gases are promising tools to quantify pulmonary microstructure noninvasively in humans and in animal models. These techniques assume the motion encoded is exclusively diffusive gas displacement, but the impact of cardiac motion on measurements has never been explored. Furthermore, although diffusion morphometry has been validated against histology in humans and mice using 3 He, it has never been validated in mice for 129 Xe. Here, we examine the effect of cardiac motion on diffusion imaging and validate 129 Xe diffusion morphometry in mice. THEORY AND METHODS Mice were imaged using gradient-echo-based diffusion imaging, and apparent diffusion-coefficient (ADC) maps were generated with and without cardiac gating. Diffusion-weighted images were fit to a previously developed theoretical model using Bayesian probability theory, producing morphometric parameters that were compared with conventional histology. RESULTS Cardiac gating had no significant impact on ADC measurements (dual-gating: ADC = 0.020 cm2 /s, single-gating: ADC = 0.020 cm2 /s; P = .38). Diffusion-morphometry-generated maps of ADC (mean, 0.0165 ± 0.0001 cm2 /s) and acinar dimensions (alveolar sleeve depth [h] = 44 µm, acinar duct radii [R] = 99 µm, mean linear intercept [Lm ] = 74 µm) that agreed well with conventional histology (h = 45 µm, R = 108 µm, Lm = 63 µm). CONCLUSION Cardiac motion has negligible impact on 129 Xe ADC measurements in mice, arguing its impact will be similarly minimal in humans, where relative cardiac motion is reduced. Hyperpolarized 129 Xe diffusion morphometry accurately and noninvasively maps the dimensions of lung microstructure, suggesting it can quantify the pulmonary microstructure in mouse models of lung disease.
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Affiliation(s)
- Peter J. Niedbalski
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Alexander S. Cochran
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH
| | - Matthew S. Freeman
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH
| | - Jinbang Guo
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Elizabeth M. Fugate
- Imaging Research Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Cory B. Davis
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Physics, West Texas A&M University, Canyon, TX
| | - Jerry Dahlke
- Department of Radiology, Duke University School of Medicine, Durham, NC
| | - James D. Quirk
- Department of Radiology, Washington University, St. Louis, MO
| | - Brian M. Varisco
- Division of Critical Care Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH
| | - Jason C. Woods
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Imaging Research Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Radiology, Washington University, St. Louis, MO
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH
| | - Zackary I. Cleveland
- Center for Pulmonary Imaging Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH
- Imaging Research Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH
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11
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von Morze C, Engelbach JA, Blazey T, Quirk JD, Reed GD, Ippolito JE, Garbow JR. Comparison of hyperpolarized 13 C and non-hyperpolarized deuterium MRI approaches for imaging cerebral glucose metabolism at 4.7 T. Magn Reson Med 2020; 85:1795-1804. [PMID: 33247884 DOI: 10.1002/mrm.28612] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [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: 05/05/2020] [Revised: 10/12/2020] [Accepted: 11/03/2020] [Indexed: 12/23/2022]
Abstract
PURPOSE The purpose of this study was to directly compare two isotopic metabolic imaging approaches, hyperpolarized (HP) 13 C MRI and deuterium metabolic imaging (DMI), for imaging specific closely related segments of cerebral glucose metabolism at 4.7 T. METHODS Comparative HP-13 C and DMI neuroimaging experiments were conducted consecutively in normal rats during the same scanning session. Localized conversions of [1-13 C]pyruvate and [6,6-2 H2 ]glucose to their respective downstream metabolic products were measured by spectroscopic imaging, using an identical 2D-CSI sequence with parameters optimized for the respective experiments. To facilitate direct comparison, a pair of substantially equivalent 2.5-cm double-tuned X/1 H RF surface coils was developed. For improved results, multidimensional low-rank reconstruction was applied to denoise the raw DMI data. RESULTS Localized conversion of HP [1-13 C]pyruvate to [1-13 C]lactate, and [6,6-2 H2 ]glucose to [3,3-2 H2 ]lactate and Glx-d (glutamate and glutamine), was detected in rat brain by spectroscopic imaging at 4.7 T. The SNR and spatial resolution of HP-13 C MRI was superior to DMI but limited to a short time window, whereas the lengthy DMI acquisition yielded maps of not only lactate, but also Glx production, albeit with relatively poor spectral discrimination between metabolites at this field strength. Across the individual rats, there was an apparent inverse correlation between cerebral production of HP [1-13 C]lactate and Glx-d, along with a trend toward increased [3,3-2 H2 ]lactate. CONCLUSION The HP-13 C MRI and DMI methods are both feasible at 4.7 T and have significant potential for metabolic imaging of specific segments of glucose metabolism.
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Affiliation(s)
- Cornelius von Morze
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
| | - John A Engelbach
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
| | - Tyler Blazey
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
| | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
| | | | - Joseph E Ippolito
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
| | - Joel R Garbow
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
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12
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von Morze C, Engelbach JA, Reed GD, Chen AP, Quirk JD, Blazey T, Mahar R, Malloy CR, Garbow JR, Merritt ME. 15 N-carnitine, a novel endogenous hyperpolarized MRI probe with long signal lifetime. Magn Reson Med 2020; 85:1814-1820. [PMID: 33179825 DOI: 10.1002/mrm.28578] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 12/22/2022]
Abstract
PURPOSE The purpose of this study was to investigate hyperpolarization and in vivo imaging of [15 N]carnitine, a novel endogenous MRI probe with long signal lifetime. METHODS L-[15 N]carnitine-d9 was hyperpolarized by the method of dynamic nuclear polarization followed by rapid dissolution. The T1 signal lifetimes were estimated in aqueous solution and in vivo following intravenous injection in rats, using a custom-built dual-tuned 15 N/1 H RF coil at 4.7 T. 15 N chemical shift imaging and 15 N fast spin-echo images of rat abdomen were acquired 3 minutes after [15 N]carnitine injection. RESULTS Estimated T1 times of [15 N]carnitine at 4.7 T were 210 seconds (in H2 O) and 160 seconds (in vivo), with an estimated polarization level of 10%. Remarkably, the [15 N]carnitine coherence was detectable in rat abdomen for 5 minutes after injection for the nonlocalized acquisition. No downstream metabolites were detected on localized or nonlocalized 15 N spectra. Diffuse liver enhancement was detected on 15 N fast spin-echo imaging 3 minutes after injection, with mean hepatic SNR of 18 ± 5 at a spatial resolution of 4 × 4 mm. CONCLUSION This study showed the feasibility of hyperpolarizing and imaging the biodistribution of HP [15 N]carnitine.
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Affiliation(s)
- Cornelius von Morze
- Mallinckrodt Institute of Radiology, Washington University, St Louis, Missouri, USA
| | - John A Engelbach
- Mallinckrodt Institute of Radiology, Washington University, St Louis, Missouri, USA
| | | | | | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University, St Louis, Missouri, USA
| | - Tyler Blazey
- Mallinckrodt Institute of Radiology, Washington University, St Louis, Missouri, USA
| | - Rohit Mahar
- Department of Biochemistry, University of Florida, Gainesville, Florida, USA
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas, Southwestern, Dallas, Texas, USA
| | - Joel R Garbow
- Mallinckrodt Institute of Radiology, Washington University, St Louis, Missouri, USA
| | - Matthew E Merritt
- Department of Biochemistry, University of Florida, Gainesville, Florida, USA
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13
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Hall CS, Quirk JD, Goss CW, Lew D, Kozlowski J, Thomen RP, Woods JC, Tustison NJ, Mugler JP, Gallagher L, Koch T, Schechtman KB, Ruset IC, Hersman FW, Castro M. Single-Session Bronchial Thermoplasty Guided by 129Xe Magnetic Resonance Imaging. A Pilot Randomized Controlled Clinical Trial. Am J Respir Crit Care Med 2020; 202:524-534. [PMID: 32510976 DOI: 10.1164/rccm.201905-1021oc] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Rationale: Adverse events have limited the use of bronchial thermoplasty (BT) in severe asthma.Objectives: We sought to evaluate the effectiveness and safety of using 129Xe magnetic resonance imaging (129Xe MRI) to prioritize the most involved airways for guided BT.Methods: Thirty subjects with severe asthma were imaged with volumetric computed tomography and 129Xe MRI to quantitate segmental ventilation defects. Subjects were randomized to treatment of the six most involved airways in the first session (guided group) or a standard three-session BT (unguided). The primary outcome was the change in Asthma Quality of Life Questionnaire score from baseline to 12 weeks after the first BT for the guided group compared with after three treatments for the unguided group.Measurements and Main Results: There was no significant difference in quality of life after one guided compared with three unguided BTs (change in Asthma Quality of Life Questionnaire guided = 0.91 [95% confidence interval, 0.28-1.53]; unguided = 1.49 [95% confidence interval, 0.84-2.14]; P = 0.201). After one BT, the guided group had a greater reduction in the percentage of poorly and nonventilated lung from baseline when compared with unguided (-17.2%; P = 0.009). Thirty-three percent experienced asthma exacerbations after one guided BT compared with 73% after three unguided BTs (P = 0.028).Conclusions: Results of this pilot study suggest that similar short-term improvements can be achieved with one BT treatment guided by 129Xe MRI when compared with standard three-treatment-session BT with fewer periprocedure adverse events.
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Affiliation(s)
- Chase S Hall
- University of Kansas School of Medicine, Kansas City, Kansas.,Washington University School of Medicine, St. Louis, Missouri
| | - James D Quirk
- Washington University School of Medicine, St. Louis, Missouri
| | - Charles W Goss
- Washington University School of Medicine, St. Louis, Missouri
| | - Daphne Lew
- Washington University School of Medicine, St. Louis, Missouri
| | - Jim Kozlowski
- Washington University School of Medicine, St. Louis, Missouri
| | | | - Jason C Woods
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | | | - John P Mugler
- University of Virginia School of Medicine, Charlottesville, Virginia; and
| | - Lora Gallagher
- Washington University School of Medicine, St. Louis, Missouri
| | - Tammy Koch
- Washington University School of Medicine, St. Louis, Missouri
| | | | | | | | - Mario Castro
- University of Kansas School of Medicine, Kansas City, Kansas.,Washington University School of Medicine, St. Louis, Missouri
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14
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Thomen RP, Woods JC, Sturm PF, Jain V, Walkup LL, Higano NS, Quirk JD, Varisco BM. Lung microstructure in adolescent idiopathic scoliosis before and after posterior spinal fusion. PLoS One 2020; 15:e0240265. [PMID: 33031412 PMCID: PMC7544066 DOI: 10.1371/journal.pone.0240265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/22/2020] [Indexed: 11/19/2022] Open
Abstract
Adolescent idiopathic scoliosis (AIS) is associated with decreased respiratory quality of life and impaired diaphragm function. Recent hyperpolarized helium (HHe) MRI studies show alveolarization continues throughout adolescence, and mechanical forces are known to impact alveolarization. We therefore hypothesized that patients with AIS would have alterations in alveolar size, alveolar number, or alveolar septal dimensions compared to adolescents without AIS, and that posterior spinal fusion (PSF) might reverse these differences. We conducted a prospective observational trial using HHe MRI to test for changes in alveolar microstructure in control and AIS subjects at baseline and one year. After obtaining written informed consent from subjects’ legal guardians and assent from the subjects, we performed HHe and proton MRI in 14 AIS and 16 control subjects aged 8–21 years. The mean age of control subjects (12.9 years) was significantly less than AIS (14.9 years, p = 0.003). At baseline, there were no significant differences in alveolar size, number, or alveolar duct morphometry between AIS and control subjects or between the concave (compressed) and convex (expanded) lungs of AIS subjects. At one year after PSF AIS subjects had an increase in alveolar density in the formerly convex lung (p = 0.05), likely reflecting a change in thoracic anatomy, but there were no other significant changes in lung microstructure. Modeling of alveolar size over time demonstrated similar rates of alveolar growth in control and AIS subjects in both right and left lungs pre- and post-PSF. Although this study suffered from poor age-matching, we found no evidence that AIS or PSF impacts lung microstructure. Trial registration: Clinical trial registration number NCT03539770.
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Affiliation(s)
- Robert P. Thomen
- School of Medicine, University of Missouri, Columbia, Missouri, United States of America
- Division of Radiology, University of Missouri, Columbia, Missouri, United States of America
| | - Jason C. Woods
- College of Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Pulmonary Medicine, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
| | - Peter F. Sturm
- College of Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Orthopaedics, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
| | - Viral Jain
- College of Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Orthopaedics, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
| | - Laura L. Walkup
- Pulmonary Medicine, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
| | - Nara S. Higano
- Pulmonary Medicine, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
| | - James D. Quirk
- Mallincrodt Institute of Radiology, Washington University, St. Louis, MO, United States of America
- School of Medicine, Washington University, St. Louis, MO, United States of America
| | - Brian M. Varisco
- College of Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Critical Care Medicine, Cincinnati Children’s Hospital, Cincinnati, Ohio, United States of America
- * E-mail:
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15
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Roy S, Whitehead TD, Quirk JD, Salter A, Ademuyiwa FO, Li S, An H, Shoghi KI. Optimal co-clinical radiomics: Sensitivity of radiomic features to tumour volume, image noise and resolution in co-clinical T1-weighted and T2-weighted magnetic resonance imaging. EBioMedicine 2020; 59:102963. [PMID: 32891051 PMCID: PMC7479492 DOI: 10.1016/j.ebiom.2020.102963] [Citation(s) in RCA: 22] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 12/12/2022] Open
Abstract
Background Radiomics analyses has been proposed to interrogate the biology of tumour as well as to predict/assess response to therapy in vivo. The objective of this work was to assess the sensitivity of radiomics features to noise, resolution, and tumour volume in the context of a co-clinical trial. Methods Triple negative breast cancer (TNBC) patients were recruited into an ongoing co-clinical imaging trial. Sub-typed matched TNBC patient-derived tumour xenografts (PDX) were generated to investigate optimal co-clinical MR radiomic features. The MR imaging protocol included T1-weighed and T2-weighted imaging. To test the sensitivity of radiomics to resolution, PDX were imaged at three different resolutions. Multiple sets of images with varying signal-to-noise ratio (SNR) were generated, and an image independent patch-based method was implemented to measure the noise levels. Forty-eight radiomic features were extracted from manually segmented 2D and 3D segmented tumours and normal tissues of T1- and T2- weighted co-clinical MR images. Findings Sixteen radiomics features were identified as volume dependent and corrected for volume-dependency following normalization. Features from grey-level run-length matrix (GLRLM), grey-level size zone matrix (GLSZM) were identified as most sensitive to noise. Radiomic features Kurtosis and Run-length variance (RLV) from GLSZM were most sensitive to changes in resolution in both T1w and T2w MRI. In general, 3D radiomic features were more robust compared to 2D (single slice) measures, although the former exhibited higher variability between subjects. Interpretation Tumour volume, noise characteristics, and image resolution significantly impact radiomic analysis in co-clinical studies.
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Affiliation(s)
- Sudipta Roy
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Timothy D Whitehead
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James D Quirk
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Amber Salter
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO USA
| | - Foluso O Ademuyiwa
- Department of Internal Medicine, Division of Oncology, Washington University School of Medicine, St. Louis, MO USA
| | - Shunqiang Li
- Department of Internal Medicine, Division of Oncology, Washington University School of Medicine, St. Louis, MO USA
| | - Hongyu An
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University School of Medicine, St. Louis, MO USA
| | - Kooresh I Shoghi
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University School of Medicine, St. Louis, MO USA.
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16
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Ge X, Quirk JD, Engelbach JA, Bretthorst GL, Li S, Shoghi KI, Garbow JR, Ackerman JJH. Test-Retest Performance of a 1-Hour Multiparametric MR Image Acquisition Pipeline With Orthotopic Triple-Negative Breast Cancer Patient-Derived Tumor Xenografts. ACTA ACUST UNITED AC 2020; 5:320-331. [PMID: 31572793 PMCID: PMC6752291 DOI: 10.18383/j.tom.2019.00012] [Citation(s) in RCA: 8] [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: 01/01/2023]
Abstract
Preclinical imaging is critical in the development of translational strategies to detect diseases and monitor response to therapy. The National Cancer Institute Co-Clinical Imaging Resource Program was launched, in part, to develop best practices in preclinical imaging. In this context, the objective of this work was to develop a 1-hour, multiparametric magnetic resonance image-acquisition pipeline with triple-negative breast cancer patient-derived xenografts (PDXs). The 1-hour, image-acquisition pipeline includes T1- and T2-weighted scans, quantitative T1, T2, and apparent diffusion coefficient (ADC) parameter maps, and dynamic contrast-enhanced (DCE) time-course images. Quality-control measures used phantoms. The triple-negative breast cancer PDXs used for this study averaged 174 ± 73 μL in volume, with region of interest–averaged T1, T2, and ADC values of 1.9 ± 0.2 seconds, 62 ± 3 milliseconds, and 0.71 ± 0.06 μm2/ms (mean ± SD), respectively. Specific focus was on assessing the within-subject test–retest coefficient-of-variation (CVWS) for each of the magnetic resonance imaging metrics. Determination of PDX volume via manually drawn regions of interest is highly robust, with ∼1% CVWS. Determination of T2 is also robust with a ∼3% CVWS. Measurements of T1 and ADC are less robust with CVWS values in the 6%–11% range. Preliminary DCE test–retest time-course determinations, as quantified by area under the curve and Ktrans from 2-compartment exchange (extended Tofts) modeling, suggest that DCE is the least robust protocol, with ∼30%–40% CVWS.
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Affiliation(s)
| | | | | | | | | | - Kooresh I Shoghi
- Departments of Radiology.,Alvin J. Siteman Cancer Center, Washington University School of Medicine and Barnes-Jewish Hospital, St Louis, MO
| | - Joel R Garbow
- Departments of Radiology.,Alvin J. Siteman Cancer Center, Washington University School of Medicine and Barnes-Jewish Hospital, St Louis, MO
| | - Joseph J H Ackerman
- Departments of Radiology.,Internal Medicine, and.,Chemistry, Washington University, St Louis, MO; and.,Alvin J. Siteman Cancer Center, Washington University School of Medicine and Barnes-Jewish Hospital, St Louis, MO
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17
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Palanisamy A, Giri T, Jiang J, Bice A, Quirk JD, Conyers SB, Maloney SE, Raghuraman N, Bauer AQ, Garbow JR, Wozniak DF. In utero exposure to transient ischemia-hypoxemia promotes long-term neurodevelopmental abnormalities in male rat offspring. JCI Insight 2020; 5:133172. [PMID: 32434985 DOI: 10.1172/jci.insight.133172] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [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: 09/03/2019] [Accepted: 04/22/2020] [Indexed: 01/08/2023] Open
Abstract
The impact of transient ischemic-hypoxemic insults on the developing fetal brain is poorly understood despite evidence suggesting an association with neurodevelopmental disorders such as schizophrenia and autism. To address this, we designed an aberrant uterine hypercontractility paradigm with oxytocin to better assess the consequences of acute, but transient, placental ischemia-hypoxemia in term pregnant rats. Using MRI, we confirmed that oxytocin-induced aberrant uterine hypercontractility substantially compromised uteroplacental perfusion. This was supported by the observation of oxidative stress and increased lactate concentration in the fetal brain. Genes related to oxidative stress pathways were significantly upregulated in male, but not female, offspring 1 hour after oxytocin-induced placental ischemia-hypoxemia. Persistent upregulation of select mitochondrial electron transport chain complex proteins in the anterior cingulate cortex of adolescent male offspring suggested that this sex-specific effect was enduring. Functionally, offspring exposed to oxytocin-induced uterine hypercontractility showed male-specific abnormalities in social behavior with associated region-specific changes in gene expression and functional cortical connectivity. Our findings, therefore, indicate that even transient but severe placental ischemia-hypoxemia could be detrimental to the developing brain and point to a possible mitochondrial link between intrauterine asphyxia and neurodevelopmental disorders.
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Affiliation(s)
- Arvind Palanisamy
- Department of Anesthesiology.,Department of Obstetrics and Gynecology
| | | | | | - Annie Bice
- Mallinckrodt Institute of Radiology, and
| | | | | | | | | | | | | | - David F Wozniak
- Department of Psychiatry, and.,Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, Missouri, USA
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18
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Higano NS, Thomen RP, Quirk JD, Huyck HL, Hahn AD, Fain SB, Pryhuber GS, Woods JC. Alveolar Airspace Size in Healthy and Diseased Infant Lungs Measured via Hyperpolarized 3He Gas Diffusion Magnetic Resonance Imaging. Neonatology 2020; 117:704-712. [PMID: 33176330 PMCID: PMC7878286 DOI: 10.1159/000511084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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] [Received: 02/11/2020] [Accepted: 08/22/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Alveolar development and lung parenchymal simplification are not well characterized in vivo in neonatal patients with respiratory morbidities, such as bronchopulmonary dysplasia (BPD). Hyperpolarized (HP) gas diffusion magnetic resonance imaging (MRI) is a sensitive, safe, nonionizing, and noninvasive biomarker for measuring airspace size in vivo but has not yet been implemented in young infants. OBJECTIVE This work quantified alveolar airspace size via HP gas diffusion MRI in healthy and diseased explanted infant lung specimens, with comparison to histological morphometry. METHODS Lung specimens from 8 infants were obtained: 7 healthy left upper lobes (0-16 months, post-autopsy) and 1 left lung with filamin-A mutation, closely representing BPD lung disease (11 months, post-transplantation). Specimens were imaged using HP 3He diffusion MRI to generate apparent diffusion coefficients (ADCs) as biomarkers of alveolar airspace size, with comparison to mean linear intercept (Lm) via quantitative histology. RESULTS Mean ADC and Lm were significantly increased throughout the diseased specimen (ADC = 0.26 ± 0.06 cm2/s, Lm = 587 ± 212 µm) compared with healthy specimens (ADC = 0.14 ± 0.03 cm2/s, Lm = 133 ± 37 µm; p < 1 × 10-7); increased values reflect enlarged airspaces. Mean ADCs in healthy specimens were significantly correlated to Lm (r = 0.69, p = 0.041). CONCLUSIONS HP gas diffusion MRI is sensitive to healthy and diseased regional alveolar airspace size in infant lungs, with good comparison to quantitative histology in ex vivo specimens. This work demonstrates the translational potential of gas MRI techniques for in vivo assessment of normal and abnormal alveolar development in neonates with pulmonary disease.
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Affiliation(s)
- Nara S Higano
- Division of Pulmonary Medicine and Department of Radiology, Center for Pulmonary Imaging Research, Cincinnati Children's Hospital, Cincinnati, Ohio, USA,
| | - Robert P Thomen
- Department of Radiology and Bioengineering, University of Missouri, Columbia, Missouri, USA
| | - James D Quirk
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Heidie L Huyck
- Division of Neonatology, Department of Pediatrics, University of Rochester, Rochester, New York, USA
| | - Andrew D Hahn
- Department of Medical Physics, 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
| | - Gloria S Pryhuber
- Division of Neonatology, Department of Pediatrics, University of Rochester, Rochester, New York, USA
| | - Jason C Woods
- Division of Pulmonary Medicine and Department of Radiology, Center for Pulmonary Imaging Research, Cincinnati Children's Hospital, Cincinnati, Ohio, USA.,Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
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19
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Fishman EF, Quirk JD, Sweet SC, Woods JC, Gierada DS, Conradi MS, Siegel MJ, Yablonskiy DA. What makes a good pediatric transplant lung: Insights from in vivo lung morphometry with hyperpolarized 3 He magnetic resonance imaging. Pediatr Transplant 2017; 21:10.1111/petr.12886. [PMID: 28120553 PMCID: PMC5378594 DOI: 10.1111/petr.12886] [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] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/19/2016] [Indexed: 11/26/2022]
Abstract
Obtaining information on transplanted lung microstructure is an important part of the current care for monitoring transplant recipients. However, until now this information was only available from invasive lung biopsy. The objective of this study was to evaluate the use of an innovative non-invasive technique, in vivo lung morphometry with hyperpolarized ³He MRI-to characterize lung microstructure in the pediatric lung transplant population. This technique yields quantitative measurements of acinar airways' (alveolar ducts and sacs) parameters, such as acinar airway radii and alveolar depth. Six pediatric lung transplant recipients with cystic fibrosis underwent in vivo lung morphometry MRI, pulmonary function testing, and quantitative CT. We found a strong correlation between lung lifespan and alveolar depth-patients with more shallow alveoli were likely to have a negative outcome sooner than those with larger alveolar depth. Combining morphometric results with CT, we also determined mean alveolar wall thickness and found substantial increases in this parameter in some patients that negatively correlated with DLCO. In vivo lung morphometry uniquely provides previously unavailable information on lung microstructure that may be predictive of a negative outcome and has a potential to aid in lung selection for transplantation.
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Affiliation(s)
- Emily F. Fishman
- Department of Pediatrics, Washington University, St. Louis, MO, USA
| | - James D. Quirk
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, USA
| | - Stuart C. Sweet
- Department of Pediatrics, Washington University, St. Louis, MO, USA
| | - Jason C. Woods
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Department of Physics, Washington University, St. Louis, MO, USA
| | - David S. Gierada
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, USA
| | - Mark S. Conradi
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, USA,Department of Physics, Washington University, St. Louis, MO, USA
| | - Marilyn J. Siegel
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, USA
| | - Dmitriy A. Yablonskiy
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, USA,Corresponding Author: Dmitriy A. Yablonskiy, Ph.D., Mallinckrodt Institute of Radiology, Washington University, 4525 Scott Avenue, Campus Box 8227, St. Louis MO, 63110, , Tel.: +1(314) 362-1815, Fax: +1(314) 362-0526
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20
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Yablonskiy DA, Sukstanskii AL, Quirk JD. Diffusion lung imaging with hyperpolarized gas MRI. NMR Biomed 2017; 30:10.1002/nbm.3448. [PMID: 26676342 PMCID: PMC4911335 DOI: 10.1002/nbm.3448] [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] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/20/2015] [Accepted: 10/22/2015] [Indexed: 05/28/2023]
Abstract
Lung imaging using conventional 1 H MRI presents great challenges because of the low density of lung tissue, lung motion and very fast lung tissue transverse relaxation (typical T2 * is about 1-2 ms). MRI with hyperpolarized gases (3 He and 129 Xe) provides a valuable alternative because of the very strong signal originating from inhaled gas residing in the lung airspaces and relatively slow gas T2 * relaxation (typical T2 * is about 20-30 ms). However, in vivo human experiments should be performed very rapidly - usually during a single breath-hold. In this review, we describe the recent developments in diffusion lung MRI with hyperpolarized gases. We show that a combination of the results of modeling of gas diffusion in lung airspaces and diffusion measurements with variable diffusion-sensitizing gradients allows the extraction of quantitative information on the lung microstructure at the alveolar level. From an MRI scan of less than 15 s, this approach, called in vivo lung morphometry, allows the provision of quantitative values and spatial distributions of the same physiological parameters as measured by means of 'standard' invasive stereology (mean linear intercept, surface-to-volume ratio, density of alveoli, etc.). In addition, the approach makes it possible to evaluate some advanced Weibel parameters characterizing lung microstructure: average radii of alveolar sacs and ducts, as well as the depth of their alveolar sleeves. Such measurements, providing in vivo information on the integrity of pulmonary acinar airways and their changes in different diseases, are of great importance and interest to a broad range of physiologists and clinicians. We also discuss a new type of experiment based on the in vivo lung morphometry technique combined with quantitative computed tomography measurements, as well as with gradient echo MRI measurements of hyperpolarized gas transverse relaxation in the lung airspaces. Such experiments provide additional information on the blood vessel volume fraction, specific gas volume and length of the acinar airways, and allow the evaluation of lung parenchymal and non-parenchymal tissue. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
| | | | - James D Quirk
- Department of Radiology, Washington University, St. Louis, MO, USA
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21
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Thomen RP, Quirk JD, Roach D, Egan‐Rojas T, Ruppert K, Yusen RD, Altes TA, Yablonskiy DA, Woods JC. Direct comparison of
129
X
e diffusion measurements with quantitative histology in human lungs. Magn Reson Med 2016; 77:265-272. [DOI: 10.1002/mrm.26120] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 12/13/2015] [Accepted: 12/17/2015] [Indexed: 12/22/2022]
Affiliation(s)
- Robert P. Thomen
- Center for Pulmonary Imaging ResearchCincinnati Children's Hospital Medical CenterCincinnati OH USA
- Department of PhysicsWashington University in St. LouisSt. Louis MO USA
| | - James D. Quirk
- Mallinckrodt Institute of RadiologyWashington University School of MedicineSt. Louis MO USA
| | - David Roach
- Center for Pulmonary Imaging ResearchCincinnati Children's Hospital Medical CenterCincinnati OH USA
| | - Tiffany Egan‐Rojas
- Center for Pulmonary Imaging ResearchCincinnati Children's Hospital Medical CenterCincinnati OH USA
| | - Kai Ruppert
- Center for Pulmonary Imaging ResearchCincinnati Children's Hospital Medical CenterCincinnati OH USA
| | - Roger D. Yusen
- Division of Pulmonary and Critical Care MedicineWashington University School of MedicineSt. Louis MO USA
| | | | - Dmitriy A. Yablonskiy
- Mallinckrodt Institute of RadiologyWashington University School of MedicineSt. Louis MO USA
| | - Jason C. Woods
- Center for Pulmonary Imaging ResearchCincinnati Children's Hospital Medical CenterCincinnati OH USA
- Department of PhysicsWashington University in St. LouisSt. Louis MO USA
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22
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Yablonskiy DA, Sukstanskii AL, Quirk JD, Woods JC, Conradi MS. Probing lung microstructure with hyperpolarized noble gas diffusion MRI: theoretical models and experimental results. Magn Reson Med 2016; 71:486-505. [PMID: 23554008 DOI: 10.1002/mrm.24729] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The introduction of hyperpolarized gases ((3)He and (129)Xe) has opened the door to applications for which gaseous agents are uniquely suited-lung MRI. One of the pulmonary applications, diffusion MRI, relies on measuring Brownian motion of inhaled hyperpolarized gas atoms diffusing in lung airspaces. In this article we provide an overview of the theoretical ideas behind hyperpolarized gas diffusion MRI and the results obtained over the decade-long research. We describe a simple technique based on measuring gas apparent diffusion coefficient (ADC) and an advanced technique, in vivo lung morphometry, that quantifies lung microstructure both in terms of Weibel parameters (acinar airways radii and alveolar depth) and standard metrics (mean linear intercept, surface-to-volume ratio, and alveolar density) that are widely used by lung researchers but were previously available only from invasive lung biopsy. This technique has the ability to provide unique three-dimensional tomographic information on lung microstructure from a less than 15 s MRI scan with results that are in good agreement with direct histological measurements. These safe and sensitive diffusion measurements improve our understanding of lung structure and functioning in health and disease, providing a platform for monitoring the efficacy of therapeutic interventions in clinical trials.
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23
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Quirk JD, Sukstanskii AL, Woods JC, Lutey BA, Conradi MS, Gierada DS, Yusen RD, Castro M, Yablonskiy DA. Experimental evidence of age-related adaptive changes in human acinar airways. J Appl Physiol (1985) 2015; 120:159-65. [PMID: 26542518 DOI: 10.1152/japplphysiol.00541.2015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 11/01/2015] [Indexed: 11/22/2022] Open
Abstract
The progressive decline of lung function with aging is associated with changes in lung structure at all levels, from conducting airways to acinar airways (alveolar ducts and sacs). While information on conducting airways is becoming available from computed tomography, in vivo information on the acinar airways is not conventionally available, even though acini occupy 95% of lung volume and serve as major gas exchange units of the lung. The objectives of this study are to measure morphometric parameters of lung acinar airways in living adult humans over a broad range of ages by using an innovative MRI-based technique, in vivo lung morphometry with hyperpolarized (3)He gas, and to determine the influence of age-related differences in acinar airway morphometry on lung function. Pulmonary function tests and MRI with hyperpolarized (3)He gas were performed on 24 healthy nonsmokers aged 19-71 years. The most significant age-related difference across this population was a 27% loss of alveolar depth, h, leading to a 46% increased acinar airway lumen radius, hence, decreased resistance to acinar air transport. Importantly, the data show a negative correlation between h and the pulmonary function measures forced expiratory volume in 1 s and forced vital capacity. In vivo lung morphometry provides unique information on age-related changes in lung microstructure and their influence on lung function. We hypothesize that the observed reduction of alveolar depth in subjects with advanced aging represents a remodeling process that might be a compensatory mechanism, without which the pulmonary functional decline due to other biological factors with advancing age would be significantly larger.
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Affiliation(s)
- James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Alexander L Sukstanskii
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Physics, Washington University, St. Louis, Missouri
| | - Barbara A Lutey
- Department of Internal Medicine, Division of Medical Education, Washington University School of Medicine, St. Louis, Missouri; and
| | - Mark S Conradi
- Department of Physics, Washington University, St. Louis, Missouri
| | - David S Gierada
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Roger D Yusen
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Mario Castro
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Dmitriy A Yablonskiy
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri;
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24
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Chang YV, Quirk JD, Yablonskiy DA. In vivo lung morphometry with accelerated hyperpolarized (3) He diffusion MRI: a preliminary study. Magn Reson Med 2015; 73:1609-14. [PMID: 24799044 PMCID: PMC4221580 DOI: 10.1002/mrm.25284] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 04/11/2014] [Accepted: 04/15/2014] [Indexed: 12/27/2022]
Abstract
PURPOSE Parallel imaging can be used to reduce imaging time and to increase the spatial coverage in hyperpolarized gas magnetic resonance imaging of the lung. In this proof-of-concept study, we investigate the effects of parallel imaging on the morphometric measurement of lung microstructure using diffusion magnetic resonance imaging with hyperpolarized (3) He. METHODS Fully sampled and under-sampled multi-b diffusion data were acquired from human subjects using an 8-channel (3) He receive coil. A parallel imaging reconstruction technique (generalized autocalibrating partially parallel acquisitions [GRAPPA]) was used to reconstruct under-sampled k-space data. The morphometric results of the generalized autocalibrating partially parallel acquisitions-reconstructed data were compared with the results of fully sampled data for three types of subjects: healthy volunteers, mild, and moderate chronic obstructive pulmonary disease patients. RESULTS Morphometric measurements varied only slightly at mild acceleration factors. The results were largely well preserved compared to fully sampled data for different lung conditions. CONCLUSION Parallel imaging, given sufficient signal-to-noise ratio, provides a reliable means to accelerate hyperpolarized-gas magnetic resonance imaging with no significant difference in the measurement of lung morphometry from the fully sampled images. GRAPPA is a promising technique to significantly reduce imaging time and/or to improve the spatial coverage for the morphometric measurement with hyperpolarized gases.
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Affiliation(s)
- Yulin V Chang
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA
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25
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Quirk JD, Chang YV, Yablonskiy DA. In vivo lung morphometry with hyperpolarized (3) He diffusion MRI: reproducibility and the role of diffusion-sensitizing gradient direction. Magn Reson Med 2015; 73:1252-7. [PMID: 24752926 PMCID: PMC4205219 DOI: 10.1002/mrm.25241] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 12/25/2022]
Abstract
PURPOSE Lung morphometry with hyperpolarized gas diffusion MRI is a highly sensitive technique for the noninvasive measurement of acinar microstructural parameters traditionally only accessible by histology. The goal of this work is to establish the reproducibility of these measurements in healthy volunteers and their dependence on the direction of the applied diffusion-sensitizing gradient. METHODS Hyperpolarized helium-3 ((3) He) lung morphometry MRI was performed on a total of five healthy subjects. Two subjects received duplicate imaging on the same day and three subjects received duplicate imaging after a 4-month or 27-month delay to assess reproducibility. Four subjects repeated the measurement during the same session with different diffusion-sensitizing gradient directions to determine the effect on the parameter estimates. RESULTS The (3) He lung morphometry measurements were reproducible over the short term and long term (e.g., % coefficient of variation [CV] of mean chord length, Lm = 2.1% and 2.9%, respectively) and across different diffusion gradient directions (Lm % CV = 2.6%). Results also show independence of field inhomogeneity effects at 1.5T. CONCLUSION (3) He lung morphometry is a reproducible technique for measuring acinar microstructure and is effectively independent of the choice of diffusion gradient direction. This provides confidence for the use of this technique to compare populations and treatment efficacy.
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Affiliation(s)
- James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
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26
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Sukstanskii AL, Quirk JD, Yablonskiy DA. Probing lung microstructure with hyperpolarized 3He gradient echo MRI. NMR Biomed 2014; 27:1451-60. [PMID: 24920182 PMCID: PMC4232999 DOI: 10.1002/nbm.3150] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/28/2014] [Accepted: 05/02/2014] [Indexed: 05/27/2023]
Abstract
In this paper we demonstrate that gradient echo MRI with hyperpolarized (3)He gas can be used for simultaneously extracting in vivo information about lung ventilation properties, alveolar geometrical parameters, and blood vessel network structure. This new approach is based on multi-gradient-echo experimental measurements of hyperpolarized (3)He gas MRI signal from human lungs and a proposed theoretical model of this signal. Based on computer simulations of (3)He atoms diffusing in the acinar airway tree in the presence of an inhomogeneous magnetic field induced by the susceptibility differences between lung tissue (alveolar septa, blood vessels) and lung airspaces, we derive analytical expressions relating the time-dependent MR signal to the geometrical parameters of acinar airways and the blood vessel network. Data obtained on eight healthy volunteers are in good agreement with literature values. This information is complementary to the information obtained by means of the in vivo lung morphometry technique with hyperpolarized 3He diffusion MRI previously developed by our group, and opens new opportunities to study lung microstructure in health and disease.
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Affiliation(s)
| | - James D Quirk
- Department of Radiology, Washington University, St. Louis MO, 63110, USA
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Tomlinson RE, Schmieder AH, Quirk JD, Lanza GM, Silva MJ. Antagonizing the αv β3 integrin inhibits angiogenesis and impairs woven but not lamellar bone formation induced by mechanical loading. J Bone Miner Res 2014; 29:1970-80. [PMID: 24644077 PMCID: PMC4323187 DOI: 10.1002/jbmr.2223] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [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] [Received: 10/14/2013] [Revised: 02/25/2014] [Accepted: 02/27/2014] [Indexed: 12/26/2022]
Abstract
Angiogenesis and osteogenesis are critically linked, although the role of angiogenesis is not well understood in osteogenic mechanical loading. In this study, either damaging or non-damaging cyclic axial compression was used to generate woven bone formation (WBF) or lamellar bone formation (LBF), respectively, at the mid-diaphysis of the adult rat forelimb. αv β3 integrin-targeted nanoparticles or vehicle was injected intravenously after mechanical loading. β3 integrin subunit expression on vasculature was maximal 7 days after damaging mechanical loading, but was still robustly expressed 14 days after loading. Accordingly, targeted nanoparticle delivery in WBF-loaded limbs was increased compared with non-loaded limbs. Vascularity was dramatically increased after WBF loading (+700% on day 14) and modestly increased after LBF loading (+50% on day 14). This increase in vascularity was inhibited by nanoparticle treatment in both WBF- and LBF-loaded limbs at days 7 and 14 after loading. Decreased vascularity led to diminished woven, but not lamellar, bone formation. Decreased woven bone formation resulted in impaired structural properties of the skeletal repair, particularly in post-yield behavior. These results demonstrate that αv β3 integrin-mediated angiogenesis is critical for recovering fracture resistance after bone injury but is not required for bone modeling after modest mechanical strain. © 2014 American Society for Bone and Mineral Research.
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Affiliation(s)
- Ryan E Tomlinson
- Department of Orthopaedic Surgery, Musculoskeletal Research Center, Washington University in St. Louis, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
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Thomen RP, Sheshadri A, Quirk JD, Kozlowski J, Ellison HD, Szczesniak RD, Castro M, Woods JC. Regional ventilation changes in severe asthma after bronchial thermoplasty with (3)He MR imaging and CT. Radiology 2014; 274:250-9. [PMID: 25144646 DOI: 10.1148/radiol.14140080] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To quantify regional lung ventilation in healthy volunteers and patients with severe asthma (both before and after thermoplasty) by using a combination of helium 3 ((3)He) magnetic resonance (MR) imaging and computed tomography (CT), with the intention of developing more effective image-guided treatments for obstructive lung diseases. MATERIALS AND METHODS With approval of the local institutional review board, informed consent, and an Investigational New Drug Exemption, six healthy volunteers and 10 patients with severe asthma were imaged in compliance with HIPAA regulations by using both multidetector CT and (3)He MR imaging. Individual bronchopulmonary segments were labeled voxel by voxel from the CT images and then registered to the (3)He MR images by using custom software. The (3)He signal intensity was then analyzed by evaluating the volume-weighted fraction of total-lung signal intensity present in each segment (segmental ventilation percentage [ SVP segmental ventilation percentage ]) and by identifying the whole-lung defect percentage and the segmental defect percentage. Of the 10 patients with asthma, seven received treatment with bronchial thermoplasty and were imaged with (3)He MR a second time. Changes in segmental defect percentages and whole-lung defect percentages are presented. RESULTS Ventilation measures for healthy volunteers yielded smaller segment-to-segment variation (mean SVP segmental ventilation percentage , 100% ± 18 [standard deviation]) than did the measures for patients with severe asthma (mean SVP segmental ventilation percentage , 97% ± 23). Patients with asthma also demonstrated larger segmental defect percentages (median, 13.5%; interquartile range, 8.9%-17.8%) than healthy volunteers (median, 6%; interquartile range, 5.6%-6.3%). These quantitative results confirm what is visually observed on the (3)He images. A Spearman correlation of r = -0.82 was found between the change in whole-lung defect percentage and the number of days between final treatment and second (3)He imaging. CONCLUSION Regional quantification of lung ventilation is indeed feasible and may be a useful technique for image-guided treatment of obstructive lung diseases, such as bronchial thermoplasty for severe asthma. In these patients, ventilation defects decreased as a function of time after treatment.
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Affiliation(s)
- Robert P Thomen
- From the Department of Physics, Washington University in St Louis, St Louis, Mo (R.P.T., H.D.E., J.C.W.); Department of Internal Medicine (A.S., J.K., M.C.) and Mallinckrodt Institute of Radiology (J.D.Q.), Washington University School of Medicine, St Louis, Mo; and Center for Pulmonary Imaging Research (R.P.T., J.C.W.) and Division of Biostatistics and Epidemiology (R.D.S.), Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229
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Pennati F, Quirk JD, Yablonskiy DA, Castro M, Aliverti A, Woods JC. Assessment of regional lung function with multivolume (1)H MR imaging in health and obstructive lung disease: comparison with (3)He MR imaging. Radiology 2014; 273:580-90. [PMID: 24937692 DOI: 10.1148/radiol.14132470] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To introduce a method based on multivolume proton (hydrogen [(1)H]) magnetic resonance (MR) imaging for the regional assessment of lung ventilatory function, investigating its use in healthy volunteers and patients with obstructive lung disease and comparing the outcome with the outcome of the research standard helium 3 ((3)He) MR imaging. MATERIALS AND METHODS The institutional review board approved the HIPAA-compliant protocol, and informed written consent was obtained from each subject. Twenty-six subjects, including healthy volunteers (n = 6) and patients with severe asthma (n = 11) and mild (n = 6) and severe (n = 3) emphysema, were imaged with a 1.5-T whole-body MR unit at four lung volumes (residual volume [ RV residual volume ], functional residual capacity [ FRC functional residual capacity ], 1 L above FRC functional residual capacity [ FRC+1 L 1 L above FRC ], total lung capacity [ TLC total lung capacity ]) with breath holds of 10-11 seconds, by using volumetric interpolated breath-hold examination. Each pair of volumes were registered, resulting in maps of (1)H signal change between the two lung volumes. (3)He MR imaging was performed at FRC+1 L 1 L above FRC by using a two-dimensional gradient-echo sequence. (1)H signal change and (3)He signal were measured and compared in corresponding regions of interest selected in ventral, intermediate, and dorsal areas. RESULTS In all volunteers and patients combined, proton signal difference between TLC total lung capacity and RV residual volume correlated positively with (3)He signal (correlation coefficient R(2) = 0.64, P < .001). Lower (P < .001) but positive correlation results from (1)H signal difference between FRC functional residual capacity and FRC+1 L 1 L above FRC (R(2) = 0.44, P < .001). In healthy volunteers, (1)H signal changes show a higher median and interquartile range compared with patients with obstructive disease and significant differences between nondependent and dependent regions. CONCLUSION Findings in this study demonstrate that multivolume (1)H MR imaging, without contrast material, can be used as a biomarker for regional ventilation, both in healthy volunteers and patients with obstructive lung disease.
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Affiliation(s)
- Francesca Pennati
- From the Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy (F.P., A.A.); Mallinckrodt Institute of Radiology (J.D.Q., D.A.Y.), Department of Internal Medicine (M.C.), and Department of Physics (J.C.W.), Washington University School of Medicine, St Louis, Mo; and Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio (J.C.W.)
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Chang YV, Quirk JD, Ruset IC, Atkinson JJ, Hersman FW, Woods JC. Quantification of human lung structure and physiology using hyperpolarized 129Xe. Magn Reson Med 2013; 71:339-44. [PMID: 24155277 DOI: 10.1002/mrm.24992] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [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: 06/13/2013] [Revised: 09/13/2013] [Accepted: 09/17/2013] [Indexed: 12/23/2022]
Abstract
PURPOSE To present in vivo, human validation of a previously proposed method to measure key pulmonary parameters related to lung microstructure and physiology. Some parameters, such as blood-air barrier thickness, cannot be measured readily by any other noninvasive modality. METHODS Healthy volunteers (n = 12) were studied in 1.5T and 3T whole body human scanners using hyperpolarized xenon. Xenon uptake by lung parenchyma and blood was measured using a chemical shift saturation recovery sequence. Both dissolved-xenon peaks at 197 ppm and 217-218 ppm were fitted against a model of xenon exchange (MOXE) as functions of exchange time. Parameters related to lung function and structure can be obtained by fitting to this model. RESULTS The following results were obtained from xenon uptake (averaged over all healthy volunteers): surface-area-to-volume ratio = 210 ± 50 cm(-1) ; total septal wall thickness = 9.2 ± 6.5 μm; blood-air barrier thickness = 1.0 ± 0.3 μm; hematocrit = 27 ± 4%; pulmonary capillary blood transit time = 1.3 ± 0.3 s, in good agreement with literature values from invasive experiments. More detailed fitting results are listed in the text. CONCLUSION The initial in vivo human results demonstrate that our proposed methods can be used to noninvasively determine lung physiology by simultaneous quantification of a few important pulmonary parameters. This method is highly promising to become a versatile screening method for lung diseases.
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Affiliation(s)
- Yulin V Chang
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri, USA; Department of Physics, Washington University, St. Louis, Missouri, USA
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Özcan A, Quirk JD, Wang Y, Wang Q, Sun P, Spees WM, Song SK. The validation of complete Fourier direct MR method for diffusion MRI via biological and numerical phantoms. Annu Int Conf IEEE Eng Med Biol Soc 2012; 2011:3756-9. [PMID: 22255156 DOI: 10.1109/iembs.2011.6090640] [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] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The equations of the Complete Fourier Direct (CFD) MR model are explicitly derived for diffusion weighted NMR experiments. The CFD-MR theory is validated by comparing a biological phantom constructed from nerve bundles and agar gel with its numerical implementation. The displacement integral distribution function estimated from the experimental data is in high agreement with the numerical phantom. CFD-MR's ability to estimate accurately and fully spin diffusion properties demonstrated here, provides the experimental validation of the theoretical CFD-MR model.
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Affiliation(s)
- Alpay Özcan
- Mallinckrodt Institute of Radiology, Washington University in Saint Louis, School of Medicine, St Louis, MO 63110, USA.
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Hajari AJ, Yablonskiy DA, Sukstanskii AL, Quirk JD, Conradi MS, Woods JC. Morphometric changes in the human pulmonary acinus during inflation. J Appl Physiol (1985) 2011; 112:937-43. [PMID: 22096115 DOI: 10.1152/japplphysiol.00768.2011] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Despite decades of research into the mechanisms of lung inflation and deflation, there is little consensus about whether lung inflation occurs due to the recruitment of new alveoli or by changes in the size and/or shape of alveoli and alveolar ducts. In this study we use in vivo (3)He lung morphometry via MRI to measure the average alveolar depth and alveolar duct radius at three levels of inspiration in five healthy human subjects and calculate the average alveolar volume, surface area, and the total number of alveoli at each level of inflation. Our results indicate that during a 143 ± 18% increase in lung gas volume, the average alveolar depth decreases 21 ±5%, the average alveolar duct radius increases 7 ± 3%, and the total number of alveoli increases by 96 ± 9% (results are means ± SD between subjects; P < 0.001, P < 0.01, and P < 0.00001, respectively, via paired t-tests). Thus our results indicate that in healthy human subjects the lung inflates primarily by alveolar recruitment and, to a lesser extent, by anisotropic expansion of alveolar ducts.
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Affiliation(s)
- A J Hajari
- Department of Physics, Washington University, St. Louis, Missouri 63110, USA
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Quirk JD, Lutey BA, Gierada DS, Woods JC, Senior RM, Lefrak SS, Sukstanskii AL, Conradi MS, Yablonskiy DA. In vivo detection of acinar microstructural changes in early emphysema with (3)He lung morphometry. Radiology 2011; 260:866-74. [PMID: 21734160 DOI: 10.1148/radiol.11102226] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE To quantitatively characterize early emphysematous changes in the lung microstructure of current and former smokers with noninvasive helium 3 ((3)He) lung morphometry and to compare these results with the clinical standards, pulmonary function testing (PFT) and low-dose computed tomography (CT). MATERIALS AND METHODS This study was approved by the local institutional review board, and all subjects provided informed consent. Thirty current and former smokers, each with a minimum 30-pack-year smoking history and mild or no abnormalities at PFT, underwent (3)He lung morphometry. This technique is based on diffusion MR imaging with hyperpolarized (3)He gas and yields quantitative localized in vivo measurements of acinar airway geometric parameters, such as airway radii, alveolar depth, and number of alveoli per unit lung volume. These measurements enable calculation of standard morphometric characteristics, such as mean linear intercept and surface-to-volume ratio. RESULTS Noninvasive (3)He lung morphometry was used to detect alterations in acinar structure in smokers with normal PFT findings. When compared with smokers with the largest forced expiratory volume in 1 second (FEV(1)) to forced vital capacity (FVC) ratio, those with chronic obstructive pulmonary disease had significantly reduced alveolar depth (0.07 mm vs 0.13 mm) and enlarged acinar ducts (0.36 mm vs 0.3 mm). The mean alveolar geometry measurements in the healthiest subjects were in excellent quantitative agreement with literature values obtained by using invasive techniques (acinar duct radius, 0.3 mm; alveolar depth, 0.14 mm at 1 L above functional residual capacity). (3)He lung morphometry depicted greater abnormalities than did PFT and CT. No adverse events were associated with inhalation of (3)He gas. CONCLUSION (3)He lung morphometry yields valuable noninvasive insight into early emphysematous changes in alveolar geometry with increased sensitivity compared with conventional techniques.
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Affiliation(s)
- James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4525 Scott Ave, Campus Box 8227, St Louis, MO 63110, USA.
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Hajari AJ, Yablonskiy DA, Quirk JD, Sukstanskii AL, Pierce RA, Deslée G, Conradi MS, Woods JC. Imaging alveolar-duct geometry during expiration via ³He lung morphometry. J Appl Physiol (1985) 2011; 110:1448-54. [PMID: 21350022 DOI: 10.1152/japplphysiol.01352.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acinar geometry has been the subject of several morphological and imaging studies in the past; however, surprisingly little is known about how the acinar microstructure changes when the lung inflates or deflates. Lung morphometry with hyperpolarized (3)He diffusion MRI allows non-destructive evaluation of lung microstructure and acinar geometry, which has important applications in understanding basic lung physiology and disease. In this study, we have measured the alveolar and acinar duct sizes at physiologically relevant volumes by (3)He lung morphometry in six normal, excised, and unfixed canine lungs. Our results imply that, during a 37% decrease in lung volume, the acinar duct radius decreases by 19%, whereas the alveolar depth increases by 9% (P < 0.0001 and P < 0.05, respectively via paired t-tests with a Bonferroni correction). A comparison to serial sections under the microscope validates the imaging results and opens the door to in vivo human studies of lung acinar geometry and physiology during respiration using (3)He lung morphometry.
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Affiliation(s)
- A J Hajari
- Department of Physics, Washington University, St. Louis, MO 63110, USA
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Osmanagic E, Sukstanskii AL, Quirk JD, Woods JC, Pierce RA, Conradi MS, Weibel ER, Yablonskiy DA. Quantitative assessment of lung microstructure in healthy mice using an MR-based 3He lung morphometry technique. J Appl Physiol (1985) 2010; 109:1592-9. [PMID: 20798272 DOI: 10.1152/japplphysiol.00736.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The recently developed technique of lung morphometry using hyperpolarized (3)He diffusion magnetic resonance (MR) (Yablonskiy DA, Sukstanskii AL, Woods JC, Gierada DS, Quirk JD, Hogg JC, Cooper JD, Conradi MS. J Appl Physiol 107: 1258-1265, 2009) permits in vivo study of lung microstructure at the alveolar level. Originally proposed for human lungs, it also has the potential to study small animals. The technique relies on theoretical developments in the area of gas diffusion in lungs linking the diffusion attenuated MR signal to the lung microstructure. To adapt this technique to small animals, certain modifications in MR protocol and data analysis are required, reflecting the smaller size of mouse alveoli and acinar airways. This is the subject of the present paper. Herein, we established empirical relationships relating diffusion measurements to geometrical parameters of lung acinar airways with dimensions typical for mice and rats by using simulations of diffusion in the airways. We have also adjusted the MR protocol to acquire data with much shorter diffusion times compared with humans to accommodate the substantially smaller acinar airway length. We apply this technique to study mouse lungs ex vivo. Our MR-based measurements yield mean values of lung surface-to-volume ratio of 670 cm(-1), alveolar density of 3,200 per mm(3), alveolar depth of 55 μm, and mean chord length of 62 μm, all consistent with published data obtained histologically in mice by unbiased methods. The proposed technique can be used for in vivo experiments, opening a door for longitudinal studies of lung morphometry in mice and other small animals.
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Affiliation(s)
- E Osmanagic
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
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Yablonskiy DA, Sukstanskii AL, Woods JC, Gierada DS, Quirk JD, Hogg JC, Cooper JD, Conradi MS. Quantification of lung microstructure with hyperpolarized 3He diffusion MRI. J Appl Physiol (1985) 2009; 107:1258-65. [PMID: 19661452 DOI: 10.1152/japplphysiol.00386.2009] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The structure and integrity of pulmonary acinar airways and their changes in different diseases are of great importance and interest to a broad range of physiologists and clinicians. The introduction of hyperpolarized gases has opened a door to in vivo studies of lungs with MRI. In this study we demonstrate that MRI-based measurements of hyperpolarized (3)He diffusivity in human lungs yield quantitative information on the value and spatial distribution of lung parenchyma surface-to-volume ratio, number of alveoli per unit lung volume, mean linear intercept, and acinar airway radii-parameters that have been used by lung physiologists for decades and are accepted as gold standards for quantifying emphysema. We validated our MRI-based method in six human lung specimens with different levels of emphysema against direct unbiased stereological measurements. We demonstrate for the first time MRI images of these lung microgeometric parameters in healthy lungs and lungs with different levels of emphysema (mild, moderate, and severe). Our data suggest that decreases in lung surface area per volume at the initial stages of emphysema are due to dramatic decreases in the depth of the alveolar sleeves covering the alveolar ducts and sacs, implying dramatic decreases in the lung's gas exchange capacity. Our novel methods are sufficiently sensitive to allow early detection and diagnosis of emphysema, providing an opportunity to improve patient treatment outcomes, and have the potential to provide safe and noninvasive in vivo biomarkers for monitoring drug efficacy in clinical trials.
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Affiliation(s)
- Dmitriy A Yablonskiy
- Mallinckrodt Inst. of Radiology, 4525 Scott Ave., Rm. 2302, St. Louis, MO 63110, USA.
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Quirk JD, Sukstanskii AL, Bretthorst GL, Yablonskiy DA. Optimal decay rate constant estimates from phased array data utilizing joint Bayesian analysis. J Magn Reson 2009; 198:49-56. [PMID: 19181549 PMCID: PMC2782647 DOI: 10.1016/j.jmr.2009.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 12/27/2008] [Accepted: 01/08/2009] [Indexed: 05/27/2023]
Abstract
Since their initial description, phased array coils have become increasingly popular due to their ease of customization for various applications. Numerous methods for combining data from individual channels have been proposed that attempt to optimize the SNR of the resultant images. One issue that has received comparatively little attention is how to apply these combination techniques to a series of images obtained from phased array coils that are then analyzed to produce quantitative estimates of tissue parameters. Herein, instead of the typical goal of maximizing the SNR in a single image, we are interested in maximizing the accuracy and precision of parameter estimates that are obtained from a series of such images. Our results demonstrate that a joint Bayesian analysis offers a "worry free" method for obtaining optimal parameter estimates from data generated by multiple coils (channels) from a single object (source). We also compare the properties of common channel combination techniques under different conditions to the results obtained from the joint Bayesian analysis. If the noise variance is constant for all channels, a sensitivity weighted average provides parameter estimates equivalent to the joint analysis. If both the noise variance and signal intensity are similar in all channels, a simple channel average gives an adequate result. However, if the noise variance differs between channels, an "ideal weighted" approach should be applied, where data are combined after weighting by the channel amplitude divided by the noise variance. Only this "ideal weighting" provides results similar to the automatic-weighting inherent in the joint Bayesian approach.
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Affiliation(s)
- James D Quirk
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4525 Scott Avenue, Campus Box 8227, St. Louis, MO 63110, USA.
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Abstract
MRI with hyperpolarized gases, (3)He, (129)Xe, (13)C, and others, has the potential to become an important diagnostic technique for clinical imaging. Due to the nonreversible loss of magnetization in hyperpolarized gas imaging, the choice of the flip angle is a major factor that influences the signal intensity, and hence, the signal-to-noise ratio. Conventional automated radiofrequency (RF) calibration procedures for (1)H imaging are not suitable for hyperpolarized gas imaging. Herein, we have demonstrated a simple procedure for RF calibration for magnetic resonance imaging (MRI) with hyperpolarized gases that is easily adaptable to clinical settings. We have demonstrated that there exists a linear relationship between the RF transmitter voltages required to obtain the same nutation angle for protons (V(1H)) and hyperpolarized gas nuclei (V(3He)). For our (1)H and (3)He coils we found that V(3He) = 1.937 . V(1H) with correlation coefficient r(2) = 0.97. This calibration can be done as a one-time procedure during the routine quality assurance (QA) protocol. The proposed procedure was found to be extremely robust in routine scanning and provided an efficient method to achieve a desired flip angle, thus allowing optimum image quality.
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Affiliation(s)
- Adil Bashir
- Mallinckrodt Institute of Radiology, St. Louis, Missouri 63110, USA
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Lutey BA, Lefrak SS, Woods JC, Tanoli T, Quirk JD, Bashir A, Yablonskiy DA, Conradi MS, Bartel ST, Pilgram TK, Cooper JD, Gierada DS. Hyperpolarized 3He MR imaging: physiologic monitoring observations and safety considerations in 100 consecutive subjects. Radiology 2008; 248:655-61. [PMID: 18641256 DOI: 10.1148/radiol.2482071838] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the safety of hyperpolarized helium 3 ((3)He) magnetic resonance (MR) imaging. MATERIALS AND METHODS Local institutional review board approval and informed consent were obtained. Physiologic monitoring data were obtained before, during, and after hyperpolarized (3)He MR imaging in 100 consecutive subjects (57 men, 43 women; mean age, 52 years +/- 14 [standard deviation]). The subjects inhaled 1-3 L of a gas mixture containing 300-500 mL (3)He and 0-2700 mL N(2) and held their breath for up to 15 seconds during MR imaging. Heart rate and rhythm and oxygen saturation of hemoglobin as measured by pulse oximetry (Spo(2)) were monitored continuously throughout each study. The effects of (3)He MR imaging on vital signs and Spo(2) and the relationship between pulmonary function, number of doses, and clinical classification (healthy volunteers, patients with asthma, heavy smokers, patients undergoing lung volume reduction surgery for severe emphysema, and patients with lung cancer) and the lowest observed Spo(2) were assessed. Any subjective symptoms were noted. RESULTS Except for a small postimaging decrease in mean heart rate (from 78 beats per minute +/- 13 to 73 beats per minute +/- 11, P < .001), there was no effect on vital signs. A mean transient decrease in Spo(2) of 4% +/- 3 was observed during the first minute after gas inhalation (P < .001) in 77 subjects who inhaled a dose of 1 L for 10 seconds or less, reaching a nadir of less than 90% at least once in 20 subjects and of less than 85% in four subjects. There was no correlation between the lowest Spo(2) and pulmonary function parameters other than baseline Spo(2) (r = 0.36, P = .001). The lowest mean Spo(2) varied by 1% between the first and second and second and third doses (P < .001) and was unrelated to clinical classification (P = .40). Minor subjective symptoms were noted by 10 subjects. No serious adverse events occurred. CONCLUSION Hyperpolarized (3)He MR imaging can be safely performed in healthy subjects, heavy smokers, and those with severe obstructive airflow limitation, although unpredictable transient desaturation suggests that potential subjects should be carefully screened for comorbidities.
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Affiliation(s)
- Barbara A Lutey
- Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, 510 S Kingshighway Blvd, St Louis, MO 63110, USA
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Quirk JD, Bretthorst GL, Duong TQ, Snyder AZ, Springer CS, Ackerman JJH, Neil JJ. Equilibrium water exchange between the intra- and extracellular spaces of mammalian brain. Magn Reson Med 2003; 50:493-9. [PMID: 12939756 DOI: 10.1002/mrm.10565] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.6] [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: 11/08/2022]
Abstract
This report describes the measurement of water preexchange lifetimes and intra/extracellular content in intact, functioning mammalian brain. Intra- and extracellular water magnetic resonance (MR) signals from rat brain in vivo were quantitatively resolved in the longitudinal relaxation domain following administration of an MR relaxation agent into the extracellular space. The estimated intracellular water content fraction was 81% +/- 8%, and the intra- to extracellular exchange rate constant was 1.81 +/- 0.89 s(-1) (mean +/- SD, N = 9), corresponding to an intracellular water preexchange lifetime of approximately 550 ms. These results provide a temporal framework for anticipating the water exchange regime (fast, intermediate, or slow) underlying a variety of compartment-sensitive measurements. The method also supplies a means by which to evaluate membrane water permeability and intra/extracellular water content serially in intact tissue. The data are obtained in an imaging mode that permits detection of regional variations in these parameters.
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Affiliation(s)
- James D Quirk
- Department of Chemistry, Washington University, St. Louis, Missouri 63110, USA
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