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Amzajerdian F, Hamedani H, Baron R, Loza L, Duncan I, Ruppert K, Kadlecek S, Rizi R. Simultaneous quantification of hyperpolarized xenon-129 ventilation and gas exchange with multi-breath xenon-polarization transfer contrast (XTC) MRI. Magn Reson Med 2023; 90:2334-2347. [PMID: 37533368 PMCID: PMC10543483 DOI: 10.1002/mrm.29804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/21/2023] [Accepted: 07/05/2023] [Indexed: 08/04/2023]
Abstract
PURPOSE To demonstrate the feasibility of a multi-breath xenon-polarization transfer contrast (XTC) MR imaging approach for simultaneously evaluating regional ventilation and gas exchange parameters. METHODS Imaging was performed in five healthy volunteers and six chronic obstructive pulmonary disease (COPD) patients. The multi-breath XTC protocol consisted of three repeated schemes of six wash-in breaths of a xenon mixture and four normoxic wash-out breaths, with and without selective saturation of either the tissue membrane or red blood cell (RBC) resonances. Acquisitions were performed at end-exhalation while subjects maintained tidal breathing throughout the session. The no-saturation, membrane-saturation, and RBC-saturation images were fit to a per-breath gas replacement model for extracting voxelwise tidal volume (TV), functional residual capacity (FRC), and fractional ventilation (FV), as well as tissue- and RBC-gas exchange (fMem and fRBC , respectively). The sensitivity of the derived model was also evaluated via simulations. RESULTS With the exception of FRC, whole-lung averages for all metrics were decreased in the COPD subjects compared to the healthy cohort, significantly so for FV, fRBC , and fMem . Heterogeneity was higher overall in the COPD subjects, particularly for fRBC , fMem , and fRBC:Mem . The anterior-to-posterior gradient associated with the gravity-dependence of lung function in supine imaging was also evident for FV, fRBC , and fMem values in the healthy subjects, but noticeably absent in the COPD cohort. CONCLUSION Multi-breath XTC imaging generated high-resolution, co-registered maps of ventilation and gas exchange parameters acquired during tidal breathing and with low per-breath xenon doses. Clear differences between healthy and COPD subjects were apparent and consistent with spirometry.
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Affiliation(s)
- Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ryan Baron
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ian Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rahim Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Pokochueva EV, Svyatova AI, Burueva DB, Koptyug IV. Chemistry of nuclear spin isomers of the molecules: from the past of the Universe to emerging technologies. Russ Chem Bull 2023. [DOI: 10.1007/s11172-023-3711-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Achekzai T, Ruppert K, Loza L, Amzajerdian F, Profka H, Duncan IF, Kadlecek SJ, Rizi RR. Investigating the impact of RF saturation-pulse parameters on compartment-selective gas-phase depolarization with xenon polarization transfer contrast MRI. Magn Reson Med 2022; 88:2447-2460. [PMID: 36046917 PMCID: PMC9529921 DOI: 10.1002/mrm.29405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/20/2022] [Accepted: 07/17/2022] [Indexed: 11/07/2022]
Abstract
PURPOSE To demonstrate the utility of continuous-wave (CW) saturation pulses in xenon-polarization transfer contrast (XTC) MRI and MRS, to investigate the selectivity of CW pulses applied to dissolved-phase resonances, and to develop a correction method for measurement biases from saturation of the nontargeted dissolved-phase compartment. METHODS Studies were performed in six healthy Sprague-Dawley rats over a series of end-exhale breath holds. Discrete saturation schemes included a series of 30 Gaussian pulses (8 ms FWHM), spaced 25 ms apart; CW saturation schemes included single block pulses, with variable flip angle and duration. In XTC imaging, saturation pulses were applied on both dissolved-phase resonance frequencies and off-resonance, to correct for other sources of signal loss and compromised selectivity. In spectroscopy experiments, saturation pulses were applied at a set of 19 frequencies spread out between 185 and 200 ppm to map out modified z-spectra. RESULTS Both modified z-spectra and imaging results showed that CW RF pulses offer sufficient depolarization and improved selectivity for generating contrast between presaturation and postsaturation acquisitions. A comparison of results obtained using a variety of saturation parameters confirms that saturation pulses applied at higher powers exhibit increased cross-contamination between dissolved-phase resonances. CONCLUSION Using CW RF saturation pulses in XTC contrast preparation, with the proposed correction method, offers a potentially more selective alternative to traditional discrete saturation. The suppression of the red blood cell contribution to the gas-phase depolarization opens the door to a novel way of quantifying exchange time between alveolar volume and hemoglobin.
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Affiliation(s)
- Tahmina Achekzai
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Harrilla Profka
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ian F. Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stephen J. Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rahim R. Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Preclinical MRI Using Hyperpolarized 129Xe. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238338. [PMID: 36500430 PMCID: PMC9738892 DOI: 10.3390/molecules27238338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 12/05/2022]
Abstract
Although critical for development of novel therapies, understanding altered lung function in disease models is challenging because the transport and diffusion of gases over short distances, on which proper function relies, is not readily visualized. In this review we summarize progress introducing hyperpolarized 129Xe imaging as a method to follow these processes in vivo. The work is organized in sections highlighting methods to observe the gas replacement effects of breathing (Gas Dynamics during the Breathing Cycle) and gas diffusion throughout the parenchymal airspaces (3). We then describe the spectral signatures indicative of gas dissolution and uptake (4), and how these features can be used to follow the gas as it enters the tissue and capillary bed, is taken up by hemoglobin in the red blood cells (5), re-enters the gas phase prior to exhalation (6), or is carried via the vasculature to other organs and body structures (7). We conclude with a discussion of practical imaging and spectroscopy techniques that deliver quantifiable metrics despite the small size, rapid motion and decay of signal and coherence characteristic of the magnetically inhomogeneous lung in preclinical models (8).
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Pilot Quality-Assurance Study of a Third-Generation Batch-Mode Clinical-Scale Automated Xenon-129 Hyperpolarizer. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27041327. [PMID: 35209116 PMCID: PMC8879294 DOI: 10.3390/molecules27041327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 11/28/2022]
Abstract
We present a pilot quality assurance (QA) study of a clinical-scale, automated, third-generation (GEN-3) 129Xe hyperpolarizer employing batch-mode spin-exchange optical pumping (SEOP) with high-Xe densities (50% natural abundance Xe and 50% N2 in ~2.6 atm total pressure sourced from Nova Gas Technologies) and rapid temperature ramping enabled by an aluminum heating jacket surrounding the 0.5 L SEOP cell. 129Xe hyperpolarization was performed over the course of 700 gas loading cycles of the SEOP cell, simulating long-term hyperpolarized contrast agent production in a clinical lung imaging setting. High levels of 129Xe polarization (avg. %PXe = 51.0% with standard deviation σPXe = 3.0%) were recorded with fast 129Xe polarization build-up time constants (avg. Tb = 25.1 min with standard deviation σTb = 3.1 min) across the first 500 SEOP cell refills, using moderate temperatures of 75 °C. These results demonstrate a more than 2-fold increase in build-up rate relative to previously demonstrated results in a comparable QA study on a second-generation (GEN-2) 129Xe hyperpolarizer device, with only a minor reduction in maximum achievable %PXe and with greater consistency over a larger number of SEOP cell refill processes at a similar polarization lifetime duration (avg. T1 = 82.4 min, standard deviation σT1 = 10.8 min). Additionally, the effects of varying SEOP jacket temperatures, distribution of Rb metal, and preparation and operation of the fluid path are quantified in the context of device installation, performance optimization and maintenance to consistently produce high 129Xe polarization values, build-up rates (Tb as low as 6 min) and lifetimes over the course of a typical high-throughput 129Xe polarization SEOP cell life cycle. The results presented further demonstrate the significant potential for hyperpolarized 129Xe contrast agent in imaging and bio-sensing applications on a clinical scale.
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Ohno Y, Seo JB, Parraga G, Lee KS, Gefter WB, Fain SB, Schiebler ML, Hatabu H. Pulmonary Functional Imaging: Part 1-State-of-the-Art Technical and Physiologic Underpinnings. Radiology 2021; 299:508-523. [PMID: 33825513 DOI: 10.1148/radiol.2021203711] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Over the past few decades, pulmonary imaging technologies have advanced from chest radiography and nuclear medicine methods to high-spatial-resolution or low-dose chest CT and MRI. It is currently possible to identify and measure pulmonary pathologic changes before these are obvious even to patients or depicted on conventional morphologic images. Here, key technological advances are described, including multiparametric CT image processing methods, inhaled hyperpolarized and fluorinated gas MRI, and four-dimensional free-breathing CT and MRI methods to measure regional ventilation, perfusion, gas exchange, and biomechanics. The basic anatomic and physiologic underpinnings of these pulmonary functional imaging techniques are explained. In addition, advances in image analysis and computational and artificial intelligence (machine learning) methods pertinent to functional lung imaging are discussed. The clinical applications of pulmonary functional imaging, including both the opportunities and challenges for clinical translation and deployment, will be discussed in part 2 of this review. Given the technical advances in these sophisticated imaging methods and the wealth of information they can provide, it is anticipated that pulmonary functional imaging will be increasingly used in the care of patients with lung disease. © RSNA, 2021 Online supplemental material is available for this article.
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Affiliation(s)
- Yoshiharu Ohno
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Joon Beom Seo
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Grace Parraga
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Kyung Soo Lee
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Warren B Gefter
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Sean B Fain
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Mark L Schiebler
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
| | - Hiroto Hatabu
- From the Department of Radiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University School of Medicine, Toyoake, Aichi, Japan (Y.O.); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan (Y.O.); Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea (J.B.S.); Department of Medicine, Robarts Research Institute, and Department of Medical Biophysics, Western University, London, Canada (G.P.); Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (SKKU-SOM), Seoul, Korea (K.S.L.); Department of Radiology, Penn Medicine, University of Pennsylvania, Philadelphia, Pa (W.B.G.); Departments of Medical Physics and Radiology (S.B.F., M.L.S.), UW-Madison School of Medicine and Public Health, Madison, Wis; and Center for Pulmonary Functional Imaging, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02215 (H.H.)
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Marshall H, Stewart NJ, Chan HF, Rao M, Norquay G, Wild JM. In vivo methods and applications of xenon-129 magnetic resonance. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2021; 122:42-62. [PMID: 33632417 PMCID: PMC7933823 DOI: 10.1016/j.pnmrs.2020.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 11/26/2020] [Accepted: 11/29/2020] [Indexed: 05/28/2023]
Abstract
Hyperpolarised gas lung MRI using xenon-129 can provide detailed 3D images of the ventilated lung airspaces, and can be applied to quantify lung microstructure and detailed aspects of lung function such as gas exchange. It is sensitive to functional and structural changes in early lung disease and can be used in longitudinal studies of disease progression and therapy response. The ability of 129Xe to dissolve into the blood stream and its chemical shift sensitivity to its local environment allow monitoring of gas exchange in the lungs, perfusion of the brain and kidneys, and blood oxygenation. This article reviews the methods and applications of in vivo129Xe MR in humans, with a focus on the physics of polarisation by optical pumping, radiofrequency coil and pulse sequence design, and the in vivo applications of 129Xe MRI and MRS to examine lung ventilation, microstructure and gas exchange, blood oxygenation, and perfusion of the brain and kidneys.
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Affiliation(s)
- Helen Marshall
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Neil J Stewart
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Ho-Fung Chan
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Madhwesha Rao
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Graham Norquay
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Jim M Wild
- POLARIS, Imaging Sciences, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom.
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8
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Amzajerdian F, Ruppert K, Hamedani H, Baron R, Xin Y, Loza L, Achekzai T, Duncan IF, Qian Y, Pourfathi M, Kadlecek S, Rizi RR. Measuring pulmonary gas exchange using compartment-selective xenon-polarization transfer contrast (XTC) MRI. Magn Reson Med 2020; 85:2709-2722. [PMID: 33283943 DOI: 10.1002/mrm.28626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 12/22/2022]
Abstract
PURPOSE To demonstrate the feasibility of generating red blood cell (RBC) and tissue/plasma (TP)-specific gas-phase (GP) depolarization maps using xenon-polarization transfer contrast (XTC) MR imaging. METHODS Imaging was performed in three healthy subjects, an asymptomatic smoker, and a chronic obstructive pulmonary disease (COPD) patient. Single-breath XTC data were acquired through a series of three GP images using a 2D multi-slice GRE during a 12 s breath-hold. A series of 8 ms Gaussian inversion pulses spaced 30 ms apart were applied in-between the images to quantify the exchange between the GP and dissolved-phase (DP) compartments. Inversion pulses were either centered on-resonance to generate contrast, or off-resonance to correct for other sources of signal loss. For an alternative scheme, inversions of both RBC and TP resonances were inserted in lieu of off-resonance pulses. Finally, this technique was extended to a multi-breath protocol consistent with tidal breathing, involving 30 consecutive acquisitions. RESULTS Inversion pulses shifted off-resonance by 20 ppm to mimic the distance between the RBC and TP resonances demonstrated selectivity, and initial GP depolarization maps illustrated stark magnitude and distribution differences between healthy and diseased subjects that were consistent with traditional approaches. CONCLUSION The proposed DP-compartment selective XTC MRI technique provides information on gas exchange between all three detectable states of xenon in the lungs and is sufficiently sensitive to indicate differences in lung function between the study subjects. Investigated extensions of this approach to imaging schemes that either minimize breath-hold duration or the overall number of breath-holds open avenues for future research to improve measurement accuracy and patient comfort.
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Affiliation(s)
- Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ryan Baron
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Tahmina Achekzai
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ian F Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yiwen Qian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rahim R Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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9
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Pravdivtsev AN, Sönnichsen FD, Hövener JB. In vitro singlet state and zero-quantum encoded magnetic resonance spectroscopy: Illustration with N-acetyl-aspartate. PLoS One 2020; 15:e0239982. [PMID: 33002045 PMCID: PMC7529218 DOI: 10.1371/journal.pone.0239982] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 09/16/2020] [Indexed: 12/20/2022] Open
Abstract
Magnetic resonance spectroscopy (MRS) allows the analysis of biochemical processes non-invasively and in vivo. Still, its application in clinical diagnostics is rare. Routine MRS is limited to spatial, chemical and temporal resolutions of cubic centimetres, mM and minutes. In fact, the signal of many metabolites is strong enough for detection, but the resonances significantly overlap, exacerbating identification and quantification. Besides, the signals of water and lipids are much stronger and dominate the entire spectrum. To suppress the background and isolate selected signals, usually, relaxation times, J-coupling and chemical shifts are used. Here, we propose methods to isolate the signals of selected molecular groups within endogenous metabolites by using long-lived spin states (LLS). We exemplify the method by preparing the LLSs of coupled protons in the endogenous molecules N-acetyl-L-aspartic acid (NAA). First, we store polarization in long-lived, double spin states, followed by saturation pulses before the spin order is converted back to observable magnetization or double quantum filters to suppress background signals. We show that LLS and zero-quantum coherences can be used to selectively prepare and measure the signals of chosen metabolites or drugs in the presence of water, inhomogeneous field and highly concentrated fatty solutions. The strong suppression of unwanted signals achieved allowed us to measure pH as a function of chemical shift difference.
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Affiliation(s)
- Andrey N Pravdivtsev
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Kiel, Germany
| | - Frank D Sönnichsen
- Otto Diels Institute for Organic Chemistry, Kiel University, Kiel, Germany
| | - Jan-Bernd Hövener
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Kiel, Germany
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10
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Birchall JR, Irwin RK, Nikolaou P, Pokochueva EV, Kovtunov KV, Koptyug IV, Barlow MJ, Goodson BM, Chekmenev EY. Pilot multi-site quality assurance study of batch-mode clinical-scale automated xenon-129 hyperpolarizers. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 316:106755. [PMID: 32512397 DOI: 10.1016/j.jmr.2020.106755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 06/11/2023]
Abstract
We present a pilot quality assurance (QA) study of spin-exchange optical pumping (SEOP) performed on two nearly identical second-generation (GEN-2) automated batch-mode clinical-scale 129Xe hyperpolarizers, each utilizing a convective forced air oven, high-power (~170 W) continuous pump laser irradiation, and xenon-rich gas mixtures (~1.30 atm partial pressure). In one study, the repeatability of SEOP in a 1000 Torr Xe/900 Torr N2/100 Torr 4He (2000 Torr total pressure) gas mixture is evaluated over the course of ~700 gas loading cycles, with negligible decrease in performance during the first ~200 cycles, and with high 129Xe polarization levels (avg. %PXe = 71.7% with standard deviation σPXe = 1.5%), build-up rates (avg. γSEOP = 0.019 min-1 with standard deviation σγ = 0.003 min-1) and polarization lifetimes (avg. T1 = 90.5 min with standard deviation σT = 10.3 min) reported at moderate oven temperature of ~70 °C. Although the SEOP cell in this study exhibited a detectable performance decrease after 400 cycles, the cell continued to produce potentially useable HP 129Xe with %PXe = 42.3 ± 0.6% even after nearly 700 refill cycles. The possibility of "regenerating" "dormant" (i.e., not used for an extended period of time) SEOP cells using repeated temperature cycling methods to recover %PXe is also demonstrated. The quality and consistency of results show significant promise for translation to clinical-scale production of hyperpolarized 129Xe contrast agents for imaging and bio-sensing applications.
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Affiliation(s)
- Jonathan R Birchall
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, MI 48202, United States.
| | - Robert K Irwin
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | | | - Ekaterina V Pokochueva
- International Tomography Center SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090, Russia
| | - Kirill V Kovtunov
- International Tomography Center SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090, Russia
| | - Igor V Koptyug
- International Tomography Center SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090, Russia
| | - Michael J Barlow
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Boyd M Goodson
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL 62901, United States; Materials Technology Center, Southern Illinois University, Carbondale, IL 62901, United States
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, MI 48202, United States; Russian Academy of Sciences, Leninskiy Prospekt 14, Moscow 119991, Russia.
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11
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Ruppert K, Amzajerdian F, Xin Y, Hamedani H, Loza L, Achekzai T, Duncan IF, Profka H, Qian Y, Pourfathi M, Kadlecek S, Rizi RR. Investigating biases in the measurement of apparent alveolar septal wall thickness with hyperpolarized 129Xe MRI. Magn Reson Med 2020; 84:3027-3039. [PMID: 32557808 DOI: 10.1002/mrm.28329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/03/2020] [Accepted: 04/29/2020] [Indexed: 02/06/2023]
Abstract
PURPOSE To investigate biases in the measurement of apparent alveolar septal wall thickness (SWT) with hyperpolarized xenon-129 (HXe) as a function of acquisition parameters. METHODS The HXe MRI scans with simultaneous gas-phase and dissolved-phase excitation were performed using 1-dimensional projection scans in mechanically ventilated rabbits. The dissolved-phase magnetization was periodically saturated, and the dissolved-phase xenon uptake dynamics were measured at end inspiration and end expiration with temporal resolutions up to 10 ms using a Look-Locker-type acquisition. The apparent alveolar septal wall thickness was extracted by fitting the signal to a theoretical model, and the findings were compared with those from the more commonly use chemical shift saturation recovery MRI spectroscopy technique with several different delay time arrangements. RESULTS It was found that repeated application of RF saturation pulses in chemical shift saturation recovery acquisitions caused exchange-dependent gas-phase saturation that heavily biased the derived SWT value. When this bias was reduced by our proposed method, the SWT dependence on lung inflation disappeared due to an inherent insensitivity of HXe dissolved-phase MRI to thin alveolar structures with very short T 2 ∗ . Furthermore, perfusion-based macroscopic gas transport processes were demonstrated to cause increasing apparent SWTs with TE (2.5 μm/ms at end expiration) and a lung periphery-to-center SWT gradient. CONCLUSION The apparent SWT measured with HXe MRI was found to be heavily dependent on the acquisition parameters. A method is proposed that can minimize this measurement bias, add limited spatial resolution, and reduce measurement time to a degree that free-breathing studies are feasible.
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Affiliation(s)
- Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Tahmina Achekzai
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ian F Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Harrilla Profka
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rahim R Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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12
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Pravdivtsev AN, Hövener JB. Simulating Non-linear Chemical and Physical (CAP) Dynamics of Signal Amplification By Reversible Exchange (SABRE). Chemistry 2019; 25:7659-7668. [PMID: 30689237 DOI: 10.1002/chem.201806133] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/18/2019] [Indexed: 01/30/2023]
Abstract
The hyperpolarization of nuclear spins by using parahydrogen (pH2 ) is a fascinating technique that allows spin polarization and thus the magnetic resonance signal to be increased by several orders of magnitude. Entirely new applications have become available. Signal amplification by reversible exchange (SABRE) is a relatively new method that is based on the reversible exchange of a substrate, catalyst and parahydrogen. SABRE is particularly interesting for in vivo medical and industrial applications, such as fast and low-cost trace analysis or continuous signal enhancement. Ever since its discovery, many attempts have been made to model and understand SABRE, with various degrees of simplifications. In this work, we reduced the simplifications further, taking into account non-linear chemical and physical (CAP) dynamics of several multi-spin systems. A master equation was derived and realized using the MOIN open-source software. The effects of different parameters (exchange rates, concentrations, spin-spin couplings) on relaxation and the polarization level have been evaluated and the results provide interesting insights into the mechanism of SABRE.
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Affiliation(s)
- Andrey N Pravdivtsev
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany
| | - Jan-Bernd Hövener
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany
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13
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Doganay O, Chen M, Matin T, Rigolli M, Phillips JA, McIntyre A, Gleeson FV. Magnetic resonance imaging of the time course of hyperpolarized 129Xe gas exchange in the human lungs and heart. Eur Radiol 2018; 29:2283-2292. [PMID: 30519929 PMCID: PMC6443604 DOI: 10.1007/s00330-018-5853-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/27/2018] [Accepted: 10/23/2018] [Indexed: 12/23/2022]
Abstract
Purpose To perform magnetic resonance imaging (MRI), human lung imaging, and quantification of the gas-transfer dynamics of hyperpolarized xenon-129 (HPX) from the alveoli into the blood plasma. Materials and methods HPX MRI with iterative decomposition of water and fat with echo asymmetry and least-square estimation (IDEAL) approach were used with multi-interleaved spiral k-space sampling to obtain HPX gas and dissolved phase images. IDEAL time-series images were then obtained from ten subjects including six normal subjects and four patients with pulmonary emphysema to test the feasibility of the proposed technique for capturing xenon-129 gas-transfer dynamics (XGTD). The dynamics of xenon gas diffusion over the entire lung was also investigated by measuring the signal intensity variations between three regions of interest, including the left and right lungs and the heart using Welch’s t test. Results The technique enabled the acquisition of HPX gas and dissolved phase compartment images in a single breath-hold interval of 8 s. The y-intersect of the XGTD curves were also found to be statistically lower in the patients with lung emphysema than in the healthy group (p < 0.05). Conclusion This time-series IDEAL technique enables the visualization and quantification of inhaled xenon from the alveoli to the left ventricle with a clinical gradient strength magnet during a single breath-hold, in healthy and diseased lungs. Key Points • The proposed hyperpolarized xenon-129 gas and dissolved magnetic resonance imaging technique can provide regional and temporal measurements of xenon-129 gas-transfer dynamics. • Quantitative measurement of xenon-129 gas-transfer dynamics from the alveolar to the heart was demonstrated in normal subjects and pulmonary emphysema. • Comparison of gas-transfer dynamics in normal subjects and pulmonary emphysema showed that the proposed technique appears sensitive to changes affecting the alveoli, pulmonary interstitium, and capillaries. Electronic supplementary material The online version of this article (10.1007/s00330-018-5853-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ozkan Doganay
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK. .,Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK.
| | - Mitchell Chen
- Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK
| | - Tahreema Matin
- Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK
| | - Marzia Rigolli
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK
| | - Julie-Ann Phillips
- Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK
| | - Anthony McIntyre
- Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK
| | - Fergus V Gleeson
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK.,Department of Radiology, The Churchill Hospital, Oxford University Hospitals NHS Trust, Old Rd, Oxford, OX3 7LE, UK
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14
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Kern AL, Gutberlet M, Voskrebenzev A, Klimeš F, Rotärmel A, Wacker F, Hohlfeld JM, Vogel‐Claussen J. Mapping of regional lung microstructural parameters using hyperpolarized
129
Xe dissolved‐phase MRI in healthy volunteers and patients with chronic obstructive pulmonary disease. Magn Reson Med 2018; 81:2360-2373. [DOI: 10.1002/mrm.27559] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Agilo L. Kern
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Marcel Gutberlet
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Andreas Voskrebenzev
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Filip Klimeš
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Alexander Rotärmel
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Frank Wacker
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
| | - Jens M. Hohlfeld
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
- Clinical Airway Research Fraunhofer Institute for Toxicology and Experimental Medicine Hannover Germany
- Department of Respiratory Medicine Hannover Medical School Hannover Germany
| | - Jens Vogel‐Claussen
- Diagnostic and Interventional Radiology Hannover Medical School Hannover Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH) Member of the German Center for Lung Research (DZL) Hannover Germany
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15
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Ruppert K, Amzajerdian F, Hamedani H, Xin Y, Loza L, Achekzai T, Duncan IF, Profka H, Siddiqui S, Pourfathi M, Sertic F, Cereda MF, Kadlecek S, Rizi RR. Assessment of flip angle-TR equivalence for standardized dissolved-phase imaging of the lung with hyperpolarized 129Xe MRI. Magn Reson Med 2018; 81:1784-1794. [PMID: 30346083 DOI: 10.1002/mrm.27538] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 08/20/2018] [Accepted: 08/27/2018] [Indexed: 12/25/2022]
Abstract
PURPOSE To investigate the feasibility of describing the impact of any flip angle-TR combination on the resulting distribution of the hyperpolarized xenon-129 (HXe) dissolved-phase magnetization in the chest using a single virtual parameter, TR90°,equiv . METHODS HXe MRI scans with simultaneous gas- (GP) and dissolved-phase (DP) excitation were performed using 2D projection scans in mechanically ventilated rabbits. Measurements with DP flip angles ranging from 6-90° and TRs ranging from 8.3-500 ms were conducted. DP maps based on acquisitions of similar radio frequency pulse-induced relaxation rates were compared. RESULTS The observed distribution of the DP magnetization was strongly affected by acquisition flip angle and TR. However, for flip angles up to 60°, measurements with the same radio frequency pulse-induced relaxation rates, resulted in very similar DP images despite the presence of significant macroscopic gas transport processes. For flip angles approaching 90°, the downstream signal component decreased noticeably relative to acquisitions with lower flip angles. Nevertheless, the total DP signal continued to follow an empirically verified conversion equation over the entire investigated parameter range, which yields the equivalent TR of a hypothetical 90° measurement for any experimental flip angle-TR combination. CONCLUSION We have introduced a method for converting the flip angle and TR of a given HXe DP measurement to a standardized metric based on the virtual quantity, TR90°,equiv , using their equivalent RF relaxation rates. This conversion permits the comparison of measurements obtained with different pulse sequence types or by different research groups using various acquisition parameters.
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Affiliation(s)
- Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Tahmina Achekzai
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ian F Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Harrilla Profka
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Sarmad Siddiqui
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Federico Sertic
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Maurizio F Cereda
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rahim R Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
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16
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Kern AL, Gutberlet M, Qing K, Voskrebenzev A, Klimeš F, Kaireit TF, Czerner C, Biller H, Wacker F, Ruppert K, Hohlfeld JM, Vogel-Claussen J. Regional investigation of lung function and microstructure parameters by localized 129 Xe chemical shift saturation recovery and dissolved-phase imaging: A reproducibility study. Magn Reson Med 2018; 81:13-24. [PMID: 30198113 DOI: 10.1002/mrm.27407] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/03/2018] [Accepted: 05/28/2018] [Indexed: 01/25/2023]
Abstract
PURPOSE To evaluate the reproducibility and regional variation of parameters obtained from localized 129 Xe chemical shift saturation recovery (CSSR) MR spectroscopy in healthy volunteers and patients with chronic obstructive pulmonary disease (COPD) and to compare the results to 129 Xe dissolved-phase MR imaging. METHODS Thirteen healthy volunteers and 10 COPD patients were scanned twice using 129 Xe dissolved-phase imaging, CSSR, and ventilation imaging sequences. A 16-channel phased-array coil in combination with the regularized spectral localization achieved by sensitivity heterogeneity (SPLASH) method was used to perform a regional analysis of CSSR data. Lung function and microstructural parameters were obtained using Patz model functions and their reproducibility was assessed. RESULTS The Patz model alveolar wall thickness parameter shows good reproducibility on a regional basis with a median coefficient of variation of 6.5% in healthy volunteers and 12.4% in COPD patients. Significant regional differences of lung function parameters derived from localized CSSR were found in healthy volunteers and correlations with spirometric indices were found. CONCLUSION Localized 129 Xe CSSR provides reproducible estimates of alveolar wall thickness and is able to detect regional differences of lung microstructure.
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Affiliation(s)
- Agilo Luitger Kern
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Marcel Gutberlet
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Kun Qing
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia
| | - Andreas Voskrebenzev
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Filip Klimeš
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Till Frederik Kaireit
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Christoph Czerner
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Heike Biller
- Clinical Airway Research, Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany
| | - Frank Wacker
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jens M Hohlfeld
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany.,Clinical Airway Research, Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany.,Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
| | - Jens Vogel-Claussen
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
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17
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Li H, Zhang Z, Zhao X, Han Y, Sun X, Ye C, Zhou X. Quantitative evaluation of pulmonary gas-exchange function using hyperpolarized 129 Xe CEST MRS and MRI. NMR IN BIOMEDICINE 2018; 31:e3961. [PMID: 30040165 DOI: 10.1002/nbm.3961] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 05/14/2018] [Accepted: 05/20/2018] [Indexed: 06/08/2023]
Abstract
Hyperpolarized 129 Xe gas MR has been a powerful tool for evaluating pulmonary structure and function due to the extremely high enhancement in spin polarization, the good solubility in the pulmonary parenchyma, and the excellent chemical sensitivity to its surrounding environment. Generally, the quantitative structural and functional information of the lung are evaluated using hyperpolarized 129 Xe by employing the techniques of chemical shift saturation recovery (CSSR) and xenon polarization transfer contrast (XTC). Hyperpolarized 129 Xe chemical exchange saturation transfer (Hyper-CEST) is another method for quantifying the exchange information of hyperpolarized 129 Xe by using the exchange of xenon signals according to its different chemical shifts, and it has been widely used in biosensor studies in vitro. However, the feasibility of using hyperpolarized 129 Xe CEST to quantify the pulmonary gas exchange function in vivo is still unclear. In this study, the technique of CEST was used to quantitatively evaluate the gas exchange in the lung globally and regionally via hyperpolarized 129 Xe MRS and MRI, respectively. A new parameter, the pulmonary apparent gas exchange time constant (Tapp ), was defined, and it increased from 0.63 s to 0.95 s in chronic obstructive pulmonary disease (COPD) rats (induced by cigarette smoke and lipopolysaccharide exposure) versus the controls with a significant difference (P = 0.001). Additionally, the spatial distribution maps of Tapp in COPD rats' pulmonary parenchyma showed a regionally obvious increase compared with healthy rats. These results indicated that hyperpolarized 129 Xe CEST MR was an effective method for globally and regionally quantifying the pulmonary gas exchange function, which would be helpful in diagnosing lung diseases that are related to gas exchange, such as COPD.
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Affiliation(s)
- Haidong Li
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhiying Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiuchao Zhao
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yeqing Han
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xianping Sun
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chaohui Ye
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xin Zhou
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
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18
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Ruppert K, Amzajerdian F, Hamedani H, Xin Y, Loza L, Achekzai T, Duncan IF, Profka H, Siddiqui S, Pourfathi M, Cereda MF, Kadlecek S, Rizi RR. Rapid assessment of pulmonary gas transport with hyperpolarized 129Xe MRI using a 3D radial double golden-means acquisition with variable flip angles. Magn Reson Med 2018; 80:2439-2448. [PMID: 29682792 DOI: 10.1002/mrm.27217] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 03/20/2018] [Accepted: 03/24/2018] [Indexed: 12/15/2022]
Abstract
PURPOSE To demonstrate the feasibility of using a 3D radial double golden-means acquisition with variable flip angles to monitor pulmonary gas transport in a single breath hold with hyperpolarized xenon-129 MRI. METHODS Hyperpolarized xenon-129 MRI scans with interleaved gas-phase and dissolved-phase excitations were performed using a 3D radial double golden-means acquisition in mechanically ventilated rabbits. The flip angle was either held fixed at 15 ° or 5 °, or it was varied linearly in ascending or descending order between 5 ° and 15 ° over a sampling interval of 1000 spokes. Dissolved-phase and gas-phase images were reconstructed at high resolution (32 × 32 × 32 matrix size) using all 1000 spokes, or at low resolution (22 × 22 × 22 matrix size) using 400 spokes at a time in a sliding-window fashion. Based on these sliding-window images, relative change maps were obtained using the highest mean flip angle as the reference, and aggregated pixel-based changes were tracked. RESULTS Although the signal intensities in the dissolve-phase maps were mostly constant in the fixed flip-angle acquisitions, they varied significantly as a function of average flip angle in the variable flip-angle acquisitions. The latter trend reflects the underlying changes in observed dissolve-phase magnetization distribution due to pulmonary gas uptake and transport. CONCLUSION 3D radial double golden-means acquisitions with variable flip angles provide a robust means for rapidly assessing lung function during a single breath hold, thereby constituting a particularly valuable tool for imaging uncooperative or pediatric patient populations.
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Affiliation(s)
- Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Tahmina Achekzai
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ian F Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Harrilla Profka
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Sarmad Siddiqui
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Maurizio F Cereda
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rahim R Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
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19
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Yablonskiy DA, Sukstanskii AL, Quirk JD. Diffusion lung imaging with hyperpolarized gas MRI. NMR IN BIOMEDICINE 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] [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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20
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Barskiy DA, Coffey AM, Nikolaou P, Mikhaylov DM, Goodson BM, Branca RT, Lu GJ, Shapiro MG, Telkki VV, Zhivonitko VV, Koptyug IV, Salnikov OG, Kovtunov KV, Bukhtiyarov VI, Rosen MS, Barlow MJ, Safavi S, Hall IP, Schröder L, Chekmenev EY. NMR Hyperpolarization Techniques of Gases. Chemistry 2017; 23:725-751. [PMID: 27711999 PMCID: PMC5462469 DOI: 10.1002/chem.201603884] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Indexed: 01/09/2023]
Abstract
Nuclear spin polarization can be significantly increased through the process of hyperpolarization, leading to an increase in the sensitivity of nuclear magnetic resonance (NMR) experiments by 4-8 orders of magnitude. Hyperpolarized gases, unlike liquids and solids, can often be readily separated and purified from the compounds used to mediate the hyperpolarization processes. These pure hyperpolarized gases enabled many novel MRI applications including the visualization of void spaces, imaging of lung function, and remote detection. Additionally, hyperpolarized gases can be dissolved in liquids and can be used as sensitive molecular probes and reporters. This Minireview covers the fundamentals of the preparation of hyperpolarized gases and focuses on selected applications of interest to biomedicine and materials science.
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Affiliation(s)
- Danila A Barskiy
- Department of Radiology, Department of Biomedical Engineering, Department of Physics, Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University, Nashville, TN, 37232, USA
| | - Aaron M Coffey
- Department of Radiology, Department of Biomedical Engineering, Department of Physics, Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University, Nashville, TN, 37232, USA
| | - Panayiotis Nikolaou
- Department of Radiology, Department of Biomedical Engineering, Department of Physics, Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University, Nashville, TN, 37232, USA
| | | | - Boyd M Goodson
- Southern Illinois University, Department of Chemistry and Biochemistry, Materials Technology Center, Carbondale, IL, 62901, USA
| | - Rosa T Branca
- Department of Physics and Astronomy, Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - George J Lu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Mikhail G Shapiro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | | | - Vladimir V Zhivonitko
- International Tomography Center SB RAS, 630090, Novosibirsk, Russia
- Novosibirsk State University, Pirogova St. 2, 630090, Novosibirsk, Russia
| | - Igor V Koptyug
- International Tomography Center SB RAS, 630090, Novosibirsk, Russia
- Novosibirsk State University, Pirogova St. 2, 630090, Novosibirsk, Russia
| | - Oleg G Salnikov
- International Tomography Center SB RAS, 630090, Novosibirsk, Russia
- Novosibirsk State University, Pirogova St. 2, 630090, Novosibirsk, Russia
| | - Kirill V Kovtunov
- International Tomography Center SB RAS, 630090, Novosibirsk, Russia
- Novosibirsk State University, Pirogova St. 2, 630090, Novosibirsk, Russia
| | - Valerii I Bukhtiyarov
- Boreskov Institute of Catalysis SB RAS, 5 Acad. Lavrentiev Pr., 630090, Novosibirsk, Russia
| | - Matthew S Rosen
- MGH/A.A. Martinos Center for Biomedical Imaging, Boston, MA, 02129, USA
| | - Michael J Barlow
- Respiratory Medicine Department, Queen's Medical Centre, University of Nottingham Medical School, Nottingham, NG7 2UH, UK
| | - Shahideh Safavi
- Respiratory Medicine Department, Queen's Medical Centre, University of Nottingham Medical School, Nottingham, NG7 2UH, UK
| | - Ian P Hall
- Respiratory Medicine Department, Queen's Medical Centre, University of Nottingham Medical School, Nottingham, NG7 2UH, UK
| | - Leif Schröder
- Molecular Imaging, Department of Structural Biology, Leibniz-Institut für Molekulare Pharmakologie (FMP), 13125, Berlin, Germany
| | - Eduard Y Chekmenev
- Department of Radiology, Department of Biomedical Engineering, Department of Physics, Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University, Nashville, TN, 37232, USA
- Russian Academy of Sciences, 119991, Moscow, Russia
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21
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Zhang Z, Guan Y, Li H, Zhao X, Han Y, Xia Y, Sun X, Liu S, Ye C, Zhou X. Quantitative comparison of lung physiological parameters in single and multiple breathhold with hyperpolarized xenon magnetic resonance. Biomed Phys Eng Express 2016. [DOI: 10.1088/2057-1976/2/5/055013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Stewart NJ, Wild JM. MRI methods for structural and functional assessment of the lungs: proton and multinuclear. IMAGING 2016. [DOI: 10.1183/2312508x.10002115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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23
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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] [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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24
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Abstract
Molecular imaging plays an important role in the era of personalized medicine, especially with recent advances in magnetic resonance (MR) probes. While the first generation of these probes focused on maximizing contrast enhancement, a second generation of probes has been developed to improve the accumulation within specific tissues or pathologies, and the newest generation of agents is also designed to report on changes in physiological status and has been termed "smart" agents. This represents a paradigm switch from the previously commercialized gadolinium and iron oxide probes to probes with new capabilities, and leads to new challenges as scanner hardware needs to be adapted for detecting these probes. In this chapter, we highlight the unique features for all five different categories of MR probes, including the emerging chemical exchange saturation transfer, (19)F, and hyperpolarized probes, and describe the key physical properties and features motivating their design. As part of this comparison, the strengths and weaknesses of each category are discussed.
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Affiliation(s)
- Michael T McMahon
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA; The Russell H. Morgan Department of Radiology and Radiological Sciences, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
| | - Kannie W Y Chan
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA; The Russell H. Morgan Department of Radiology and Radiological Sciences, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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25
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Kovtunov KV, Truong ML, Barskiy D, Salnikov OG, Bukhtiyarov V, Coffey AM, Waddell KW, Koptyug IV, Chekmenev EY. Propane- d6 Heterogeneously Hyperpolarized by Parahydrogen. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2014; 118:28234-28243. [PMID: 25506406 PMCID: PMC4259496 DOI: 10.1021/jp508719n] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/06/2014] [Indexed: 05/20/2023]
Abstract
Long-lived spin states of hyperpolarized propane-d6 gas were demonstrated following pairwise addition of parahydrogen gas to propene-d6 using heterogeneous parahydrogen-induced polarization (HET-PHIP). Hyperpolarized molecules were synthesized using Rh/TiO2 solid catalyst with 1.6 nm Rh nanoparticles. Hyperpolarized (PH ∼ 1%) propane-d6 was detected at high magnetic field (9.4 T) spectroscopically and by high-resolution 3D gradient-echo MRI (4.7 T) as the gas flowed through the radiofrequency coil with a spatial and temporal resolution of 0.5 × 0.5 × 0.5 mm3 and 17.7 s, respectively. Stopped-flow hyperpolarized propane-d6 gas was also detected at 0.0475 T with an observed nuclear spin polarization of PH ∼ 0.1% and a relatively long lifetime with T1,eff = 6.0 ± 0.3 s. Importantly, it was shown that the hyperpolarized protons of the deuterated product obtained via pairwise parahydrogen addition could be detected directly at low magnetic field. Importantly, the relatively long low-field T1,eff of HP propane-d6 gas is not susceptible to paramagnetic impurities as tested by exposure to ∼0.2 atm oxygen. This long lifetime and nontoxic nature of propane gas could be useful for bioimaging applications including potentially pulmonary low-field MRI. The feasibility of high-resolution low-field 2D gradient-echo MRI was demonstrated with 0.88 × 0.88 mm2 spatial and ∼0.7 s temporal resolution, respectively, at 0.0475 T.
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Affiliation(s)
- Kirill V. Kovtunov
- International
Tomography Center, 3A
Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk
State University, 2 Pirogova
St., Novosibirsk, 630090, Russia
- E-mail:
| | - Milton L. Truong
- Institute of Imaging Science, Department
of Radiology, Department of Biomedical
Engineering, Department of Physics and Astronomy, Department of Biochemistry, Vanderbilt-Ingram Cancer
Center, Vanderbilt University, Nashville, Tennessee 37232-2310, United States
| | - Danila
A. Barskiy
- International
Tomography Center, 3A
Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk
State University, 2 Pirogova
St., Novosibirsk, 630090, Russia
| | - Oleg G. Salnikov
- International
Tomography Center, 3A
Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk
State University, 2 Pirogova
St., Novosibirsk, 630090, Russia
| | - Valery
I. Bukhtiyarov
- Boreskov
Institute of Catalysis, SB RAS, 5 Acad. Lavrentiev Pr., Novosibirsk 630090, Russia
| | - Aaron M. Coffey
- Institute of Imaging Science, Department
of Radiology, Department of Biomedical
Engineering, Department of Physics and Astronomy, Department of Biochemistry, Vanderbilt-Ingram Cancer
Center, Vanderbilt University, Nashville, Tennessee 37232-2310, United States
| | - Kevin W. Waddell
- Institute of Imaging Science, Department
of Radiology, Department of Biomedical
Engineering, Department of Physics and Astronomy, Department of Biochemistry, Vanderbilt-Ingram Cancer
Center, Vanderbilt University, Nashville, Tennessee 37232-2310, United States
| | - Igor V. Koptyug
- International
Tomography Center, 3A
Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk
State University, 2 Pirogova
St., Novosibirsk, 630090, Russia
| | - Eduard Y. Chekmenev
- Institute of Imaging Science, Department
of Radiology, Department of Biomedical
Engineering, Department of Physics and Astronomy, Department of Biochemistry, Vanderbilt-Ingram Cancer
Center, Vanderbilt University, Nashville, Tennessee 37232-2310, United States
- E-mail:
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26
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Cleveland ZI, Virgincar RS, Qi Y, Robertson SH, Degan S, Driehuys B. 3D MRI of impaired hyperpolarized 129Xe uptake in a rat model of pulmonary fibrosis. NMR IN BIOMEDICINE 2014; 27:1502-14. [PMID: 24816478 PMCID: PMC4229493 DOI: 10.1002/nbm.3127] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/17/2014] [Accepted: 03/31/2014] [Indexed: 05/24/2023]
Abstract
A variety of pulmonary pathologies, in particular interstitial lung diseases, are characterized by thickening of the pulmonary blood-gas barrier, and this thickening results in reduced gas exchange. Such diffusive impairment is challenging to quantify spatially, because the distributions of the metabolically relevant gases (CO2 and O2) cannot be detected directly within the lungs. Hyperpolarized (HP) (129)Xe is a promising surrogate for these metabolic gases, because MR spectroscopy and imaging allow gaseous alveolar (129)Xe to be detected separately from (129)Xe dissolved in the red blood cells (RBCs) and the adjacent tissues, which comprise blood plasma and lung interstitium. Because (129)Xe reaches the RBCs by diffusing across the same barrier tissues (blood plasma and interstitium) as O2, barrier thickening will delay (129)Xe transit and, thus, reduce RBC-specific (129)Xe MR signal. Here we have exploited these properties to generate 3D, MR images of (129)Xe uptake by the RBCs in two groups of rats. In the experimental group, unilateral fibrotic injury was generated prior to imaging by instilling bleomycin into one lung. In the control group, a unilateral sham instillation of saline was performed. Uptake of (129)Xe by the RBCs, quantified as the fraction of RBC signal relative to total dissolved (129)Xe signal, was significantly reduced (P = 0.03) in the injured lungs of bleomycin-treated animals. In contrast, no significant difference (P = 0.56) was observed between the saline-treated and untreated lungs of control animals. Together, these results indicate that 3D MRI of HP (129)Xe dissolved in the pulmonary tissues can provide useful biomarkers of impaired diffusive gas exchange resulting from fibrotic thickening.
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Affiliation(s)
- Zackary I. Cleveland
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
| | - Rohan, S. Virgincar
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
- Department of Biomedical Engineering, Duke University, Durham, NC
| | - Yi Qi
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
| | - Scott H. Robertson
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
- Graduate Program in Medical Physics; Duke University Medical Center, Durham, NC
| | - Simone Degan
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
- Center for Molecular and Biomolecular Imaging, Duke University, Durham, NC
| | - Bastiaan Driehuys
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC
- Department of Biomedical Engineering, Duke University, Durham, NC
- Graduate Program in Medical Physics; Duke University Medical Center, Durham, NC
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27
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Walkup LL, Woods JC. Translational applications of hyperpolarized 3He and 129Xe. NMR IN BIOMEDICINE 2014; 27:1429-1438. [PMID: 24953709 DOI: 10.1002/nbm.3151] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 04/07/2014] [Accepted: 05/19/2014] [Indexed: 06/03/2023]
Abstract
Clinical magnetic resonance imaging of the lung is technologically challenging, yet over the past two decades hyperpolarized noble gas ((3)He and (129)Xe) imaging has demonstrated the ability to measure multiple pulmonary functional biomarkers. There is a growing need for non-ionizing, non-invasive imaging techniques due to increased concern about cancer risk from ionizing radiation, but the translation of hyperpolarized gas imaging to the pulmonary clinic has been stunted by limited access to the technology. New developments may open doors to greater access and more translation to clinical studies. Here we briefly review a few translational applications of hyperpolarized gas MRI in the contexts of ventilation, diffusion, and dissolved-phase imaging, as well as comparing and contrasting (3)He and (129)Xe gases for these applications. Simple static ventilation MRI reveals regions of the lung not participating in normal ventilation, and these defects have been observed in many pulmonary diseases. Biomarkers related to airspace size and connectivity can be quantified by apparent diffusion coefficient measurements of hyperpolarized gas, and have been shown to be more sensitive to small changes in lung morphology than standard clinical pulmonary functional tests and have been validated by quantitative histology. Parameters related to gas uptake and exchange and lung tissue density can be determined using (129)Xe dissolved-phase MRI. In most cases functional biomarkers can be determined via MRI of either gas, but for some applications one gas may be preferred, such as (3)He for long-range diffusion measurements and (129)Xe for dissolved-phase imaging. Greater access to hyperpolarized gas imaging coupled with newly developing therapeutics makes pulmonary medicine poised for a potential revolution, further adding to the prospects of personalized medicine already evidenced by advancements in molecular biology. Hyperpolarized gas researchers have the opportunity to contribute to this revolution, particularly if greater clinical application of hyperpolarized gas imaging is realized.
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Affiliation(s)
- Laura L Walkup
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
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28
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Qing K, Mugler JP, Altes TA, Jiang Y, Mata JF, Miller GW, Ruset IC, Hersman FW, Ruppert K. Assessment of lung function in asthma and COPD using hyperpolarized 129Xe chemical shift saturation recovery spectroscopy and dissolved-phase MRI. NMR IN BIOMEDICINE 2014; 27:1490-501. [PMID: 25146558 PMCID: PMC4233004 DOI: 10.1002/nbm.3179] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 07/10/2014] [Accepted: 07/11/2014] [Indexed: 05/03/2023]
Abstract
Magnetic-resonance spectroscopy and imaging using hyperpolarized xenon-129 show great potential for evaluation of the most important function of the human lung -- gas exchange. In particular, chemical shift saturation recovery (CSSR) xenon-129 spectroscopy provides important physiological information for the lung as a whole by characterizing the dynamic process of gas exchange, while dissolved-phase (DP) xenon-129 imaging captures the time-averaged regional distribution of gas uptake by lung tissue and blood. Herein, we present recent advances in assessing lung function using CSSR spectroscopy and DP imaging in a total of 45 subjects (23 healthy, 13 chronic obstructive pulmonary disease (COPD) and 9 asthma). From CSSR acquisitions, the COPD subjects showed red blood cell to tissue-plasma (RBC-to-TP) ratios below the average for the healthy subjects (p < 0.001), but significantly higher septal wall thicknesses as compared with the healthy subjects (p < 0.005); the RBC-to-TP ratios for the asthmatic subjects fell outside two standard deviations (either higher or lower) from the mean of the healthy subjects, although there was no statistically significant difference for the average ratio of the study group as a whole. Similarly, from the 3D DP imaging acquisitions, we found that all the ratios (TP to gas phase (GP), RBC to GP, RBC to TP) measured in the COPD subjects were lower than those from the healthy subjects (p < 0.05 for all ratios), while these ratios in the asthmatic subjects differed considerably between subjects. Despite having been performed at different lung inflation levels, the RBC-to-TP ratios measured by CSSR and 3D DP imaging were fairly consistent with each other, with a mean difference of 0.037 (ratios from 3D DP imaging larger). In ten subjects the RBC-to-GP ratios obtained from the 3D DP imaging acquisitions were also highly correlated with their diffusing capacity of the lung for carbon monoxide per unit alveolar volume ratios measured by pulmonary function testing (R = 0.91).
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Affiliation(s)
- Kun Qing
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - John P. Mugler
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Talissa A. Altes
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Yun Jiang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Jaime F. Mata
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - G. Wilson Miller
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Iulian C. Ruset
- Xemed LLC, Durham, NH, USA
- Department of Physics, University of New Hampshire, Durham, NH, USA
| | - F. William Hersman
- Xemed LLC, Durham, NH, USA
- Department of Physics, University of New Hampshire, Durham, NH, USA
| | - Kai Ruppert
- Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
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29
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Stewart NJ, Leung G, Norquay G, Marshall H, Parra-Robles J, Murphy PS, Schulte RF, Elliot C, Condliffe R, Griffiths PD, Kiely DG, Whyte MK, Wolber J, Wild JM. Experimental validation of the hyperpolarized129Xe chemical shift saturation recovery technique in healthy volunteers and subjects with interstitial lung disease. Magn Reson Med 2014; 74:196-207. [DOI: 10.1002/mrm.25400] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Neil J. Stewart
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - General Leung
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Graham Norquay
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Helen Marshall
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Juan Parra-Robles
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | | | | | - Charlie Elliot
- Academic Directorate of Respiratory Medicine; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
- Sheffield Pulmonary Vascular Disease Unit; Sheffield Teaching Hospitals, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Robin Condliffe
- Academic Directorate of Respiratory Medicine; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
- Sheffield Pulmonary Vascular Disease Unit; Sheffield Teaching Hospitals, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Paul D. Griffiths
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - David G. Kiely
- Academic Directorate of Respiratory Medicine; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
- Sheffield Pulmonary Vascular Disease Unit; Sheffield Teaching Hospitals, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Moira K. Whyte
- Academic Directorate of Respiratory Medicine; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
| | - Jan Wolber
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
- Medical Diagnostics; GE Healthcare; Amersham United Kingdom
| | - Jim M. Wild
- Academic Unit of Radiology; University of Sheffield, Royal Hallamshire Hospital; Sheffield United Kingdom
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30
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Stem cells and cell therapies in lung biology and diseases: conference report. Ann Am Thorac Soc 2014; 10:S25-44. [PMID: 23869447 DOI: 10.1513/annalsats.201304-089aw] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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31
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Leung G, Norquay G, Schulte RF, Wild JM. Radiofrequency pulse design for the selective excitation of dissolved 129Xe. Magn Reson Med 2014; 73:21-30. [PMID: 24395490 DOI: 10.1002/mrm.25089] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 10/30/2013] [Accepted: 11/27/2013] [Indexed: 12/25/2022]
Abstract
PURPOSE To optimize radiofrequency (RF) pulses for the selective excitation of dissolved phase (129)Xe that take into account the very short T2*, while simultaneously, minimally exciting the much larger gas signal. METHODS Numerical simulations of Shinnar le-Roux pulses and binomial coefficient composite-element pulses were performed and experimentally implemented on a 1.5 Tesla (T) clinical scanner. These were compared with pulses commonly used for short T2* imaging from the literature. The pulses were then experimentally tested in vivo with healthy volunteers inhaling hyperpolarized (129)Xe using nuclear MR spectroscopy on a 1.5T clinical scanner. RESULTS Standard RF excitation pulses inadvertently excite the gas compartment, or are long enough that the T2* of the dissolved compartment deteriorates the received signal. Amplitude modulated binomial composite pulses perform well being short and having high selectivity, however, deteriorate at high amplifier gain setting. Composite pulses using pulse width modulation provide the desired frequency response even in these nonlinear, high gain regimes. CONCLUSION Composite pulses provide a means of very narrow band frequency selectivity in a short duration pulse that is well suited to dissolved (129)Xe imaging. Pulse width modulation maintains the desired frequency response even in the presence of amplitude distortion.
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Affiliation(s)
- General Leung
- Unit of Academic Radiology, University of Sheffield, Sheffield, United Kingdom
| | - Graham Norquay
- Unit of Academic Radiology, University of Sheffield, Sheffield, United Kingdom
| | | | - Jim M Wild
- Unit of Academic Radiology, University of Sheffield, Sheffield, United Kingdom
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Kirby M, Parraga G. Pulmonary functional imaging using hyperpolarized noble gas MRI: six years of start-up experience at a single site. Acad Radiol 2013; 20:1344-56. [PMID: 24119346 DOI: 10.1016/j.acra.2013.02.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 01/31/2013] [Accepted: 02/01/2013] [Indexed: 12/01/2022]
Abstract
RATIONALE AND OBJECTIVES In this review, we summarize our experience evaluating pulmonary function in 330 different subjects using hyperpolarized noble gas magnetic resonance imaging (MRI) after enrollment and screening of >1100 subjects with and without respiratory disease during the period February 1, 2006, through November 1, 2012. MATERIALS AND METHODS We discuss the feasibility of hyperpolarized gas MRI research in a small nonhospital research unit and provide an overview of our experience since we initiated patient-based studies. We also discuss the importance of infrastructure support, collaboration, research trainees, and a large and willing patient population that helped to advance the research and technological deliverables. A summary of patient safety and tolerability, key feasibility, and research milestones is provided, as well as a roadmap for future studies. RESULTS Hyperpolarized (3)He and (129)Xe gas MRI is feasible at smaller centers without significant human resources for large and small longitudinal studies by virtue of its excellent patient safety and tolerability, the speed with which images can be acquired and quantitatively analyzed and the high spatial-temporal dynamics of the method that allows for acute and chronic therapy studies. CONCLUSIONS The hyperpolarized noble gas MRI community's highly collaborative efforts and motivation to further the development and application of this tool has resulted in a moment-of-opportunity to translate the method clinically to provide an improved understanding of pulmonary disease. There are, as well, new and unprecedented opportunities for the evaluation of disease progression and to help develop the new treatments and interventions critically required for chronic pulmonary disease.
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Affiliation(s)
- Miranda Kirby
- Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada, N6A 5K8; Department of Medical Biophysics, London, Canada
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Abstract
A better understanding of the anatomic structure and physiological function of the lung is fundamental to understanding the pathogenesis of pulmonary disease and how to design and deliver better treatments and measure response to intervention. Magnetic resonance imaging (MRI) with the hyperpolarised noble gases helium-3 ((3)He) and xenon-129 ((129)Xe) provides both structural and functional pulmonary measurements, and because it does not require the use of x-rays or other ionising radiation, offers the potential for intensive serial and longitudinal studies in paediatric patients. These facts are particularly important in the evaluation of chronic lung diseases such as asthma and cystic fibrosis- both of which can be considered paediatric respiratory diseases with unmet therapy needs. This review discusses MRI-based imaging methods with a focus on hyperpolarised gas MRI. We also discuss the strengths and limitations as well as the future work required for clinical translation towards paediatric respiratory disease.
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Affiliation(s)
- Miranda Kirby
- Imaging Research Laboratories, Robarts Research Institute, London, Canada.
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Witte C, Schröder L. NMR of hyperpolarised probes. NMR IN BIOMEDICINE 2013; 26:788-802. [PMID: 23033215 DOI: 10.1002/nbm.2873] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 07/23/2012] [Accepted: 08/29/2012] [Indexed: 06/01/2023]
Abstract
Increasing the sensitivity of NMR experiments is an ongoing field of research to help realise the exquisite molecular specificity of this technique. Hyperpolarisation of various nuclei is a powerful approach that enables the use of NMR for molecular and cellular imaging. Substantial progress has been achieved over recent years in terms of both tracer preparation and detection schemes. This review summarises recent developments in probe design and optimised signal encoding, and promising results in sensitive disease detection and efficient therapeutic monitoring. The different methods have great potential to provide molecular specificity not available by other diagnostic modalities.
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Affiliation(s)
- Christopher Witte
- ERC Project BiosensorImaging, Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
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Svenningsen S, Kirby M, Starr D, Leary D, Wheatley A, Maksym GN, McCormack DG, Parraga G. Hyperpolarized (3) He and (129) Xe MRI: differences in asthma before bronchodilation. J Magn Reson Imaging 2013; 38:1521-30. [PMID: 23589465 DOI: 10.1002/jmri.24111] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 02/12/2013] [Indexed: 01/22/2023] Open
Abstract
PURPOSE To compare hyperpolarized helium-3 ((3) He) and xenon-129 ((129) Xe) MRI in asthmatics before and after salbutamol inhalation. MATERIALS AND METHODS Seven asthmatics provided written informed consent and underwent spirometry, plethysmography, and MRI before and after salbutamol inhalation. (3) He and (129) Xe ventilation defect percent (VDP) and ventilation coefficient of variation (COV) were measured. To characterize the airways spatially related to ventilation defects, wall area percent (WA%) and lumen area (LA) were evaluated for two subjects who had thoracic x-ray computed tomography (CT) acquired 1 year before MRI. RESULTS Before salbutamol inhalation, (129) Xe VDP (8 ± 5%) was significantly greater than (3) He VDP (6 ± 5%, P = 0.003). Post-salbutamol, there was a significant improvement in both (129) Xe (5 ± 4%, P < 0.0001) and (3) He (4 ± 3%, P = 0.001) VDP, and the improvement in (129) Xe VDP was significantly greater (P = 0.008). (129) Xe MRI COV (Pre: 0.309 ± 0.028, Post: 0.296 ± 0.036) was significantly greater than (3) He MRI COV (Pre: 0.282 ± 0.018, Post: 0.269 ± 0.024), pre- (P < 0.0001) and post-salbutamol (P < 0.0001) and the decrease in COV post-salbutamol was significant ((129) Xe, P = 0.002; (3) He, P < 0.0001). For a single asthmatic, a sub-segmental (129) Xe MRI ventilation defect that was visible only before salbutamol inhalation but not visible using (3) He MRI was spatially related to a remodeled fourth generation sub-segmental airway (WA% = 78%, LA = 2.9 mm(2) ). CONCLUSION In asthma, hyperpolarized (129) Xe MRI may help reveal ventilation abnormalities before bronchodilation that are not observed using hyperpolarized (3) He MRI.
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Affiliation(s)
- Sarah Svenningsen
- Imaging Research Laboratories, Robarts Research Institute, London, Canada; Department of Medical Biophysics, The University of Western Ontario, London, Canada
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Kirby M, Svenningsen S, Kanhere N, Owrangi A, Wheatley A, Coxson HO, Santyr GE, Paterson NAM, McCormack DG, Parraga G. Pulmonary ventilation visualized using hyperpolarized helium-3 and xenon-129 magnetic resonance imaging: differences in COPD and relationship to emphysema. J Appl Physiol (1985) 2013; 114:707-15. [DOI: 10.1152/japplphysiol.01206.2012] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In subjects with chronic obstructive pulmonary disease (COPD), hyperpolarized xenon-129 (129Xe) magnetic resonance imaging (MRI) reveals significantly greater ventilation defects than hyperpolarized helium-3 (3He) MRI. The physiological and/or morphological determinants of ventilation defects and the differences observed between hyperpolarized 3He and 129Xe MRI are not yet understood. Here we aimed to determine the structural basis for the differences in ventilation observed between 3He and 129Xe MRI in subjects with COPD using apparent diffusion coefficients (ADC) and computed tomography (CT). Ten COPD ex-smokers provided written, informed consent and underwent MRI, CT, spirometry, and plethysmography. 3He and 129Xe MRI ventilation volume was generated using semiautomated segmentation, and ADC maps were registered to generate ADC values for lung regions of interest ventilated by both gases (ADCHX) and by 3He gas only (ADCHO). CT wall area percentage and the lowest 15th percentile point of the CT lung density histogram (HU15%) were also evaluated. For lung regions accessed by 3He gas only, mean 3He ADCHO was significantly greater than for regions accessed by both gases (ADCHO = 0.503 ± 0.119 cm2/s, ADCHX = 0.470 ± 0.125 cm2/s, P < 0.0001). The difference between 3He and 129Xe ventilation volume was significantly correlated with CT HU15% ( r = −65, P = 0.04) and 3He ADCHO ( r = 0.70, P = 0.02), but not CT wall area percentage ( r = −0.34, P = 0.33). In conclusion, in this small study in COPD subjects, we observed significantly decreased 129Xe MRI ventilation compared with 3He MRI, and these regions of decreased 129Xe ventilation were spatially and significantly correlated with regions of increased pulmonary emphysema, but not airway wall thickness.
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Affiliation(s)
- Miranda Kirby
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
| | - Sarah Svenningsen
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
| | - Nikhil Kanhere
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada
| | - Amir Owrangi
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada
| | - Andrew Wheatley
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
| | - Harvey O. Coxson
- Department of Radiology & James Hogg Research Centre, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Giles E. Santyr
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
| | - Nigel A. M. Paterson
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada
| | - David G. McCormack
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada
| | - Grace Parraga
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
- Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada
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