preparation of mri scanner room and subject positioning for 129xe mri of lung ventilation

超极化 129Xe MRI 研究肺功能的标准化工作流程

Hyperpolarized 129Xe MRI is an exciting tool for non-invasive, spatially-resolved characterization and quantification of specific aspects of pulmonary function1,2,3. Acquisition and reconstruction approaches similar to those used in anatomical proton MRI yield images of inhaled 129Xe in the lungs, permitting visualization of non-ventilated lung regions and region-resolved quantification of ventilation distribution4,5,6,7,8. More advanced pulse sequence and analysis techniques yield further complementary information, including quantification of gas-exchange efficacy between alveoli and pulmonary capillaries via spectroscopic MRI9,10,11,12,13 and characterization of alveolar microstructure integrity via diffusion-weighted MRI14,15,16.
Inhaled 129Xe has been proven safe and tolerable in adult and pediatric subjects, including those with pulmonary disease17,18. Measurements of lung function derived from 129Xe MRI have shown sensitivity to structural and functional alterations in many pulmonary disease contexts, including chronic obstructive pulmonary disease6,10,19, cystic fibrosis20,21,22, idiopathic pulmonary fibrosis23,24,25, and asthma7,10,26. Given the high safety and tolerability of 129Xe MRI, the lack of ionizing radiation in MRI compared with other common imaging approaches, and the high reproducibility of 129Xe MRI results27,28, 129Xe MRI holds significant promise, in particular for precise serial monitoring of individuals receiving a time course of therapy for chronic pulmonary disease.
The safety and clinical promise of 129Xe MRI have led to its FDA approval in December 2022 for lung ventilation imaging in persons aged 12 years and older29. Given this, it is anticipated that the number of research and clinical sites capable of performing 129Xe MRI (currently ~20 worldwide) will increase significantly over the coming years. As 129Xe MRI spreads to new institutions, it is important that robust methodological resources exist to allow sites to build out clinically relevant 129Xe MRI techniques quickly and to perform scans and generate results that are closely comparable with those of existing sites.
In this work, we will outline the current best practices for human hyperpolarized 129Xe MRI of lung ventilation, as agreed upon by member institutions of the 129Xe MRI Clinical Trials Consortium (Xe MRI CTC) and summarized in a recent position paper30. Topics will include the preparation of tailored pulse sequences ideal for a complete 129Xe MRI workflow, preparation, and administration of hyperpolarized 129Xe gas, an optimized workflow for human 129Xe MRI sessions, and best practices for monitoring subject safety and comfort during MRI sessions.

作者聚焦：使用 129Xe MRI 推进肺部成像的标准化和最佳实践

获取肺通气的超极化 129Xe 磁共振图像

Our research seeks to establish Xenon MRI as a clinical tool for characterizing lung function. Xenon MRI allows us to directly visualize ventilation defects in patients with obstructive lung diseases like COPD, asthma, and cystic fibrosis. It offers information that can't be obtained from standard MRI and pulmonary function test.Xenon MRI was recently approved by the FDA for clinical evaluation of lung ventilation. This represents a culmination of a huge amount of effort by the people in our field and it's an exciting opportunity to show how Xenon MRI can improve patient care and outcomes in pulmonary disease. Xenon MRI is still a relatively new family of techniques, and standardization is still an ongoing process.This protocol distills the existing standards for Xenon ventilation MRI into a form that we hope will be useful to research in clinical sites who are trying to perform these scans for the first time. Common clinical readouts of lung function, like pulmonary function tests, only give a single number for the entire lung with no spatial information included. Xenon MRI can make regional assessments of several aspects of lung health and function, which we believe will be very useful in the clinic.Only a few institutions are currently performing Xenon MRI, but we expect there will be many more sites soon considering the recent FDA approval. We hope that this Xenon ventilation MRI protocol will serve as a blueprint for new sites and help em to ramp up their Xenon MRI operations more quickly.

肺通气 129Xe MRI 的 MRI 扫描仪室的制备和受试者定位

首先，确保任何进入 MRI 扫描室的人都已从身体或口袋中取出所有金属和电子物体。准备 Xenon 129 背心线圈，将其插入扫描仪并将其放在 MRI 扫描仪患者工作台上。根据扫描室的布局，指示受试者以脚先仰卧或头先仰卧位躺在病床上。根据需要将枕头放在受试者的头部、膝盖等下方，以确保手术过程中的舒适度。将 Xenon 129 背心线圈固定在受试者胸部周围，同时当受试者处于舒适的充气水平时，将线圈中线保持在头脚方向，尽可能靠近受试者肺部的预期中线。将线圈放在受试者的低位可能会导致肺部外围的不良信号减少。在 MRI 扫描室的病床旁边设置一个 MRI 安全脉搏血氧仪，并将脉搏血氧仪探头连接到受试者。验证脉搏血氧仪读数是否正确。将鼻插管放在受试者的鼻子中，并将其连接到氧气源，以便在需要时在剂量吸入后使用。根据当地安全政策，以 MRI 安全方式将氧气罐和调节器放置在可触及的距离内。将患者工作台推进到 MRI 扫描仪中，将线圈的中线或受试者的肺部对齐到扫描仪的等中心。此处显示的图像代表了一项研究的通风图像，该研究是在不知不觉中使用带有损坏电缆的 Xenon 129 背心线圈进行的。右肺的信噪比低于左肺。这里显示了一项研究的通风图像，该研究是在将 Xenon 129 背心线圈放置在离受试者脚太远的地方进行的。由于缺乏接收器灵敏度，在两个肺尖中观察到人为的低氙 129 信号。

Research

JoVE Journal

Medicine

Preparation of MRI Scanner Room and Subject Positioning for 129Xe MRI of Lung Ventilation

Acquiring Hyperpolarized 129Xe Magnetic Resonance Images of Lung Ventilation

Hyperpolarized 129Xe MRI comprises a unique array of structural and functional lung imaging techniques. Technique standardization across sites is ...

科研

医学

Pre-Scan Preparation and Coaching of Subject for 129Xe MRI of Lung Ventilation

受试者进行 129Xe 肺通气 MRI 的预扫描准备和指导

Performing 129Xe MRI Scan of Lung Ventilation to Assess Pulmonary Function

进行肺通气 的 129Xe MRI 扫描以评估肺功能