Name: Troubleshooting and Quality Assurance in Hyperpolarized Xenon Magnetic Resonance Imaging: Tools for High-Quality Image Acquisition (Video) | JoVE Journal
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Description: Learn quality assurance protocols for hyperpolarized xenon-129 MRI to optimize pulmonary imaging. This method enables high-resolution visualization of lung ventilation and gas exchange without ionizing radiation.

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Obtaining High-Quality Hyperpolarized Xenon-129 Magnetic Resonance Images

<ol><li>Pellegrino, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Interpretative+strategies+for+lung+function+tests%5BTitle%5D)+AND+%22European+Respiratory+Journal%22%5BJournal%5D)">Interpretative strategies for lung function tests.</a> European Respiratory Journal. 26 (5), 948-968 (2005).</li>
<li>Ebner, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hyperpolarized+129Xenon+MRI+to+quantify+regional+ventilation+differences+in+mild+to+moderate+asthma%3A+A+prospective+comparison+between+semi-automated+ventilation+defect+percentage+calculation+and+pulmonary+function+tests%5BTitle%5D)+AND+%22Investigative+Radiology%22%5BJournal%5D)">Hyperpolarized 129Xenon MRI to quantify regional ventilation differences in mild to moderate asthma: A prospective comparison between semi-automated ventilation defect percentage calculation and pulmonary function tests.</a> Investigative Radiology. 52 (2), 120-127 (2017).</li>
<li>Abuelhia, E., Alghamdi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Evaluation+of+arising+exposure+of+ionizing+radiation+from+computed+tomography+and+the+associated+health+concerns%5BTitle%5D)+AND+%22Journal+of+Radiation+Research+and+Applied+Sciences%22%5BJournal%5D)">Evaluation of arising exposure of ionizing radiation from computed tomography and the associated health concerns.</a> Journal of Radiation Research and Applied Sciences. 13 (1), 295-300 (2020).</li>
<li>Kern, A. L., Vogel-Claussen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hyperpolarized+gas+MRI+in+pulmonology%5BTitle%5D)+AND+%22The+British+Journal+of+Radiology%22%5BJournal%5D)">Hyperpolarized gas MRI in pulmonology.</a> The British Journal of Radiology. 91 (1084), 20170647(2018).</li>
<li>Möller, H. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((MRI+of+the+lungs+using+hyperpolarized+noble+gases%5BTitle%5D)+AND+%22Magnetic+Resonance+in+Medicine%22%5BJournal%5D)">MRI of the lungs using hyperpolarized noble gases.</a> Magnetic Resonance in Medicine. 47 (6), 1029-1051 (2002).</li>
<li>Salerno, M., Altes, T. A., Mugler, J. P., Nakatsu, M., Hatabu, H., de Lange, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hyperpolarized+noble+gas+MR+imaging+of+the+lung%3A+Potential+clinical+applications%5BTitle%5D)+AND+%22European+Journal+of+Radiology%22%5BJournal%5D)">Hyperpolarized noble gas MR imaging of the lung: Potential clinical applications.</a> European Journal of Radiology. 40 (1), 33-44 (2001).</li>
<li>US FDA. New Drug Therapy Approvals at 2022. , https://www.fda.gov/drugs/new-drugs-fda-cders-new-molecular-entities-and-new-therapeutic-biological-products/new-drug-therapy-approvals-2022 (2023).</li>
<li>Nikolaou, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Near-unity+nuclear+polarization+with+an+open-source+129Xe+hyperpolarizer+for+NMR+and+MRI%5BTitle%5D)+AND+%22Proceedings+of+the+National+Academy+of+Sciences%22%5BJournal%5D)">Near-unity nuclear polarization with an open-source 129Xe hyperpolarizer for NMR and MRI.</a> Proceedings of the National Academy of Sciences. 110 (35), 14150-14155 (2013).</li>
<li>Birchall, J. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((XeUS%3A+A+second-generation+automated+open-source+batch-mode+clinical-scale+hyperpolarizer%5BTitle%5D)+AND+%22Journal+of+Magnetic+Resonance%22%5BJournal%5D)">XeUS: A second-generation automated open-source batch-mode clinical-scale hyperpolarizer.</a> Journal of Magnetic Resonance. 319, 106813(2020).</li>
<li>He, M., Zha, W., Tan, F., Rankine, L., Fain, S., Driehuys, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+comparison+of+two+hyperpolarized+129Xe+MRI+ventilation+quantification+pipelines%3A+The+effect+of+signal+to+noise+ratio%5BTitle%5D)+AND+%22Academic+Radiology%22%5BJournal%5D)">A comparison of two hyperpolarized 129Xe MRI ventilation quantification pipelines: The effect of signal to noise ratio.</a> Academic Radiology. 26 (7), 949-959 (2019).</li>
<li>Niedbalski, P. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Protocols+for+multi-site+trials+using+hyperpolarized+129+Xe+MRI+for+imaging+of+ventilation%2C+alveolar-airspace+size%2C+and+gas+exchange%3A+A+position+paper+from+the+129+Xe+MRI+clinical+trials+consortium%5BTitle%5D)+AND+%22Magnetic+Resonance+in+Medicine%22%5BJournal%5D)">Protocols for multi-site trials using hyperpolarized 129 Xe MRI for imaging of ventilation, alveolar-airspace size, and gas exchange: A position paper from the 129 Xe MRI clinical trials consortium.</a> Magnetic Resonance in Medicine. 86 (6), 2966-2986 (2021).</li>
<li>Möller, H. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((MRI+of+the+lungs+using+hyperpolarized+noble+gases%5BTitle%5D)+AND+%22Magnetic+Resonance+in+Medicine%22%5BJournal%5D)">MRI of the lungs using hyperpolarized noble gases.</a> Magnetic Resonance in Medicine. 47 (6), 1029-1051 (2002).</li>
<li>Bier, E. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+thermally+polarized+129Xe+phantom+for+quality+assurance+in+multi-center+hyperpolarized+gas+MRI+studies%5BTitle%5D)+AND+%22Magnetic+Resonance+in+Medicine%22%5BJournal%5D)">A thermally polarized 129Xe phantom for quality assurance in multi-center hyperpolarized gas MRI studies.</a> Magnetic Resonance in Medicine. 82 (5), 1961-1968 (2019).</li>
<li>Wild, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Comparison+between+2D+and+3D+gradient-echo+sequences+for+MRI+of+human+lung+ventilation+with+hyperpolarized+3He%5BTitle%5D)+AND+%22Magnetic+Resonance+in+Medicine%22%5BJournal%5D)">Comparison between 2D and 3D gradient-echo sequences for MRI of human lung ventilation with hyperpolarized 3He.</a> Magnetic Resonance in Medicine. 52 (3), 673-678 (2004).</li>
<li>Garrison, W. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Lung+volume+dependence+and+repeatability+of+hyperpolarized+129Xe+MRI+gas+uptake+metrics+in+healthy+volunteers+and+participants+with+COPD%5BTitle%5D)+AND+%22Radiology%3A+Cardiothoracic+Imaging%22%5BJournal%5D)">Lung volume dependence and repeatability of hyperpolarized 129Xe MRI gas uptake metrics in healthy volunteers and participants with COPD.</a> Radiology: Cardiothoracic Imaging. 5 (3), e220096(2023).</li>
<li>Ni, W., Qi, J., Liu, L., Li, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+pulse+signal+preprocessing+method+based+on+the+Chauvenet+criterion%5BTitle%5D)+AND+%22Computational+and+Mathematical+Methods+in+Medicine%22%5BJournal%5D)">A pulse signal preprocessing method based on the Chauvenet criterion.</a> Computational and Mathematical Methods in Medicine. 2019, 2067196(2019).</li>
<li>129Xe MRI Clinical Trials Consortium. , https://www.129xectc.org (2023).</li>
</ol>

Robert Thomen has provided consulting to Polarean, LLC.

The ability to troubleshoot 129Xe MRI issues is a necessary skill and may help mitigate problems in real time. Until a hyperpolarized gas infrastructure can be purchased from a single party and garner support from scanner manufacturers, these quality control tasks are the sole responsibility of the individual laboratories. The goal of this manuscript is to provide the reader with helpful practices and suggestions for the inevitable event of poor data acquisition. While we attempt to address as many potential issues as possible, many other challenges in 129Xe MRI are specific to the scanner manufacturer and cannot be discussed in detail due to intellectual property restrictions. However, the 129Xe Clinical Trials Consortium, a community with the express goal of developing multi-site trials using 129Xe MRI, consists of many site participants and veteran experts with experience operationalizing 129Xe MRI on multiple platforms and software17. It is recommended to contact any of the site participants with any implementation and/or troubleshooting questions that are not addressed here.
Regular performance checks of the coil should be performed to identify early indications of signal decrease or emerging noise issues. These checks involve examining the coil interface and internal connections, as well as assessing the potential impact of falls or excessive weight on the coil. In addition to physical inspections, comparing the spectroscopy scans frequently can aid in identifying issues with the coil&#39;s performance. As the multinuclear functionality of the MRI system is a shared component with the proton facility, any newly introduced devices or equipment in the magnetic room should undergo testing to prevent potential interference in xenon frequency. In addition to technical considerations, attention to detail in experimental procedures should be given. This encompasses effectively coaching subjects, ensuring clear communication with study coordinators, and precise positioning of the xenon bag during QC scans. These seemingly minor details should not be overlooked, as they can substantially improve image quality and overall study outcomes.
The protocol presented in this paper offers researchers a comprehensive framework to identify and address potential issues during the imaging process. By systematically following the troubleshooting steps, researchers can optimize image quality, enhance data accuracy, and advance the field of hyperpolarized xenon MRI. Continued refinement and adaptation of these troubleshooting strategies, coupled with advancements in imaging technology, will contribute to further improvements in the quality and reliability of hyperpolarized xenon MRI studies.

For over a century, lung function assessment has primarily relied on global measurements from spirometry and body plethysmography. However, these traditional pulmonary function tests (PFTs) are limited in their ability to capture early-stage disease&#39;s regional nuances and subtle changes in lung tissue1. Nuclear medicine with inhaled radiotracers has been used widely for the assessment of ventilation/perfusion mismatches commonly associated with pulmonary emboli, but this involves ionizing radiation and yields lower resolution. In contrast, computed tomography (CT) has emerged as the gold standard for lung imaging, offering exceptional spatial and temporal clarity compared to nuclear imaging2. While low-dose CT scans can mitigate radiation exposure, potential radiation risk should still be considered3,4. Proton MRI of the lung is uncommon due to low tissue density of the lung and rapid signal decay from lung tissue, although recent advances offer functional information despite potential low signal. On the other hand, hyperpolarized xenon magnetic resonance imaging (HP 129Xe MRI) is a non-invasive modality that allows for imaging of lung function with regional specificity5,6. It produces a high nonequilibrium nuclear magnetization of the gas in liter quantities. The inert gas is then inhaled by a subject inside the MR scanner for a single breath and is directly imaged by the scanner. Thus, the inhaled gas is directly imaged as opposed to the tissue itself. This technique has been used to assess lung ventilation across many diseases, including asthma, chronic obstructive pulmonary disease (COPD), cystic fibrosis, idiopathic pulmonary fibrosis, coronavirus disease 2019 (COVID-19), and many others3. In December 2022, HP 129Xe MRI was approved by the United States FDA as an MRI ventilation contrast agent to be used in the United States of America (USA) in adults and pediatric patients aged 12 years and older7. Physicians can now use 129Xe MRI to better care for patients with improved/personalized treatment plans.
Historically, clinical MRI focuses exclusively on imaging hydrogen nuclei (protons) which are abundant in nearly all human viscera. The MRI scanners, sequences, and quality control are generally maintained by the scanner manufacturer as part of the site license and warranty. However, 129Xe requires a multinuclear capable MR scanner and has required a dedicated research team to operationalize the hyperpolarizer, custom-built radiofrequency (RF) coils, dedicated pulse sequences, and offline reconstruction/analysis software. Each of these components can be supplied by third-party vendors or developed in-house. Thus, the burden of quality control generally rests on the 129Xe research team as opposed to the scanner manufacturer or individual third party. Consistent acquisition of high-quality 129Xe data is therefore uniquely challenging as each component of the 129Xe MRI process introduces the potential for error, which must be closely monitored by the 129Xe team. Not only can these situations be extremely frustrating as researchers have to troubleshoot and investigate possible causes for any challenges that may have arisen, but they can be very costly as this slows down patient imaging and subject recruitment. Some costs associated with troubleshooting involve MRI time costs, the hyperpolarization of 129Xe, which involves the consumption of different gases, and the use of materials. Additionally, with the recent FDA approval and growth in 129Xe imaging, providing a standardized protocol for quality control is necessary to avoid common issues and setbacks in 129Xe operation8,9.
Here, we present some of the more commonly encountered issues in 129Xe MRI, including RF coil failures, the emergence of various noise profiles that lead to low signal-to-noise ratio (SNR), and poor quality images10. We aim to provide some concise quality control (QC) guidelines and protocols to ensure the acquisition of high-quality image data and troubleshoot some of the more common issues that can arise in 129Xe MRI. The insights provided here are also relevant for hyperpolarized helium-3 troubleshooting.

<table><tbody><tr><td>Polarization measurement station&amp;nbsp;</td><td>Polerean</td><td>42881</td><td>https://polarean.com/</td></tr><tr><td>Pressure vessele with plunger valve</td><td>Ace glass</td><td>8648-85</td><td>https://www.aceglass.com/html/3dissues/Pressure_Vessels/offline/download.pdf</td></tr><tr><td>Tedlar bag</td><td>Jensen inert</td><td>GST381S-0707TJO&amp;nbsp;&amp;nbsp;</td><td>http://www.jenseninert.com/</td></tr><tr><td>Xenon Hyperpolarizer 9820</td><td>Polerean</td><td>49820</td><td>https://polarean.com/</td></tr><tr><td>Xenon loop coil</td><td>Clinical MR Solutions</td><td>Custom device</td><td>https://www.sbir.gov/sbc/clinical-mr-solutions-llc</td></tr><tr><td>Xenon vest coil</td><td>Clinical MR Solutions</td><td>Custom device</td><td>https://www.sbir.gov/sbc/clinical-mr-solutions-llc</td></tr></tbody></table>

troubleshooting and quality assurance in hyperpolarized xenon magnetic resonance imaging: tools for high-quality image acquisition

Troubleshooting and Quality Assurance in Hyperpolarized Xenon Magnetic Resonance Imaging: Tools for High-Quality Image Acquisition

Hyperpolarized (HP) xenon magnetic resonance imaging (129Xe MRI) is a recently federal drug administration (FDA)-approved imaging modality that produces high-resolution images of an inhaled breath of xenon gas for investigation of lung function. However, implementing 129Xe MRI is uniquely challenging as it requires specialized hardware and equipment for hyperpolarization, procurement of xenon imaging coils and coil software, development and compilation of multinuclear MR imaging sequences, and reconstruction/analysis of acquired data. Without proper expertise, these tasks can be daunting, and failure to acquire high-quality images can be&#160;frustrating, and expensive. Here, we present some quality control (QC) protocols, troubleshooting practices, and helpful tools for129Xe MRI sites, which may aid in the acquisition of optimized, high-quality data and accurate results. The discussion will begin with an overview of the process for implementing HP 129Xe MRI, including requirements for a hyperpolarizer lab, the combination of 129Xe MRI coil hardware/software, data acquisition and sequence considerations, data structures, k-space and image properties, and measured signal and noise characteristics. Within each of these necessary steps lies opportunities for errors, challenges, and unfavorable occurrences leading to poor image quality or failed imaging, and this presentation aims to address some of the more commonly encountered issues. In particular, identification and characterization of anomalous noise patterns in acquired data are necessary to avoid image artifacts and low-quality images; examples will be given, and mitigation strategies will be discussed. We aim to make the 129Xe MRI implementation process easier for new sites while providing some guidelines and strategies for real-time troubleshooting.

Figure 4 depicts the results of the noise characterization analysis performed on the noise scan. The plot demonstrates the impact of both regular and irregular noise on the k-space, where the deviation from the ideal y=x reference line is observed. Regular noise leads to a continuous pattern in the k-space, while irregular noise results in high-value outliers in the QQ plot.
Moving on to Figure 5, a series of lung images acquired using HPG MRI is presented. The top row showcases examples in the image space, including a reference scan, a lung image affected by regular and/or irregular noise, and an image with no signal. The bottom row displays the corresponding k-space modulus representations.
In Figure 5A, a distinct bright spot is centered in the k-space, indicating a clear lung signal with low noise. Conversely, Figure 5B shows the presence of regular noise (Gaussian noise) spread throughout the images. In Figure 5C, irregular noise is evident, causing high-value spikes in the k-space and resulting in a stripe pattern in image space. Figure 5D illustrates a scenario where both regular and irregular noises are present simultaneously, affecting the lung image. Lastly, Figure 5E represents a case where no signal is detected in the acquired lung image.
Figure 6 illustrates an instance of coarse data discretization compared with properly scaled k-space data. Upon calculating the SNR, it becomes evident that the discretized data exhibits a low signal level.
<img alt="Xenon gas pressurization setup, glass tube in LN2 dewar, diagram and real photo, chemistry technique." class="xfigimg" src="/files/ftp_upload/65972/65972fig01.jpg" data-altupdatedat="1788304762000" data-alt="Figure 1"> 
Figure 1: Illustration of creating a xenon phantom. The pressure vessel is placed in a small amount of liquid nitrogen to make the xenon freeze at around -203.15 °C (70 K). A bag of 129Xe is connected directly to the vessel. As the xenon diffuses into the vessel, it freezes upon touching the cold walls, creating a frozen snow-like structure. Once fully frozen, the vessel is sealed, and the xenon is allowed to thaw, resulting in increased pressure within the vessel. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="MRI spectroscopy setup with ¹H and ¹²⁹Xe phantoms, vest coil; used for imaging research." class="xfigimg" src="/files/ftp_upload/65972/65972fig02.jpg" data-altupdatedat="1788304762000" data-alt="Figure 2"> 
Figure 2: Arrangement for spectroscopy. (A) 129-Xenon phantom positioned between two proton phantoms, all enclosed within a 129Xe vest coil. (B) Secure the xenon vest coil with straps. (C) Insert the assembly into the magnet's bore for localization. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Signal analysis, variable bandwidth excitation, graph of frequency response, 4000-12000 Hz comparison." class="xfigimg" src="/files/ftp_upload/65972/65972fig03.jpg" data-altupdatedat="1788304762000" data-alt="Figure 3"> 
Figure 3: Signal response in relation to variable bandwidth excitation at a constant xenon frequency (34,081,645 Hz). Increasing bandwidth results in a higher noise floor. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Noise analysis: K-space diagram, histogram, QQ plot showcasing noise levels; data fitting results." class="xfigimg" src="/files/ftp_upload/65972/65972fig04.jpg" data-altupdatedat="1788304762000" data-alt="Figure 4"> 
Figure 4: Three types of noise scans: acceptable, regular, and irregular noise. (A) Panel A displays the k-space modulus representation of each noise pattern, with regular noise exhibiting a stripe pattern and irregular noise showing spikes (bright spots). (B) Histogram of the real and imaginary parts of k-space data for each noise scan. (C) The QQ plot of the real/imaginary components of k-space data, comparing the acquired dataset with a normally distributed dataset of equal mean and standard deviation in ascending order. The red line represents the y = x reference line. Deviations from this line indicate the presence of non-Gaussian components within the acquired data. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Noise effect on MRI scans; comparison diagram with k-space data analysis." class="xfigimg" src="/files/ftp_upload/65972/65972fig05.jpg" data-altupdatedat="1788304762000" data-alt="Figure 5"> 
Figure 5: Illustration of different noise patterns in HPG 129Xe lung imaging. The top row displays image space examples, including a reference scan, a lung image with regular and/or irregular noise, and an image with no signal. The bottom row shows the corresponding k-space modulus representations. In the image with the signal, a bright spot is centered in the k-space, representing the lung signal. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="K-space diagram with signal-to-noise ratio, analyzing digital precision effects on MR images." class="xfigimg" src="/files/ftp_upload/65972/65972fig06.jpg" data-altupdatedat="1788304762000" data-alt="Figure 6"> 
Figure 6: Illustration of the effect of high/low digital precision in 129Xe test bag reconstructed data. For the high digital precision image (top row), the image has a high SNR of 600, and the modulus of 55th row of K-space shows a smooth curve showing fine details of the data. However, in the low digital precision image (bottom row), individual data points are "binned" to a limited number of digital levels that cover the signal range, resulting in reduced SNR (SNR = 98) in the reconstructed image. This issue can only be identified through careful examination of the raw signal data, as it does not prevent the production of a seemingly satisfactory image. <a href="https://www.jove.com/files/ftp_upload/65972/65972fig06large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Here, we present a protocol for obtaining high-quality hyperpolarized xenon-129 magnetic resonance images, covering hardware, software, data acquisition, sequence selection, data management, k-space utilization, and noise analysis.

Hyperpolarized (HP) xenon magnetic resonance imaging (129Xe MRI) is a recently federal drug administration (FDA)-approved imaging modality that produces ...

troubleshooting-quality-assurance-hyperpolarized-xenon-magnetic

Research

JoVE Journal

Bioengineering

The production of hyperpolarized xenon by means of spin exchange optical pumping (SEOP) is described. This method yields a ~10000-fold enhancement of the nuclear spin polarization of Xe-129 and has applications in nuclear magnetic resonance spectroscopy and imaging. Examples of gas phase and solution state experiments are given.

Hyperpolarized Xenon for NMR and MRI Applications

Hyperpolarized 129Xe magnetic resonance imaging (MRI) is a method for studying regionally resolved aspects of pulmonary function. This work presents an end-to-end standardized workflow for hyperpolarized 129Xe MRI of lung ventilation, with specific attention to pulse sequence design, 129Xe dose preparation, scan workflow, and best practices for subject safety monitoring.

Acquiring Hyperpolarized 129Xe Magnetic Resonance Images of Lung Ventilation

The manuscript presents a detailed protocol for using hyperpolarized Xenon-129 chemical shift saturation recovery (CSSR) to trace pulmonary gas exchange, assess the apparent alveolar septal wall thickness, and measure the surface-to-volume ratio. The method has the potential to diagnose and monitor lung diseases.

Quantitative Measure of Lung Structure and Function Obtained from Hyperpolarized Xenon Spectroscopy

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Learn quality assurance protocols for hyperpolarized xenon-129 MRI to optimize pulmonary imaging. This method enables high-resolution visualization of lung ventilation and gas exchange without ionizing radiation.

Troubleshooting and Quality Assurance in Hyperpolarized Xenon Magnetic Resonance Imaging: Tools for High-Quality Image Acquisition (Video) | JoVE Journal

Troubleshooting and Quality Assurance in Hyperpolarized Xenon Magnetic Resonance Imaging: Tools for High-Quality Image Acquisition

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