Lung MRI with hyperpolarised gases: current & future clinical perspectives

Abstract

The use of pulmonary MRI in a clinical setting has historically been limited. Whilst CT remains the gold-standard for structural lung imaging in many clinical indications, technical developments in ultrashort and zero echo time MRI techniques are beginning to help realise non-ionising structural imaging in certain lung disorders. In this invited review, we discuss a complementary technique – hyperpolarised (HP) gas MRI with inhaled 3He and 129Xe – a method for functional and microstructural imaging of the lung that has great potential as a clinical tool for early detection and improved understanding of pathophysiology in many lung diseases. HP gas MRI now has the potential to make an impact on clinical management by enabling safe, sensitive monitoring of disease progression and response to therapy. With reference to the significant evidence base gathered over the last two decades, we review HP gas MRI studies in patients with a range of pulmonary disorders, including COPD/emphysema, asthma, cystic fibrosis, and interstitial lung disease. We provide several examples of our experience in Sheffield of using these techniques in a diagnostic clinical setting in challenging adult and paediatric lung diseases.

Treatment Trials in Young Patients with Chronic Obstructive Pulmonary Disease and Pre–Chronic Obstructive Pulmonary Disease Patients: Time to Move Forward

“…Other imaging techniques also hold promise. For instance, polarized gas MRI can identify abnormalities in diffusion and ventilation, which may precede the development of clinically overt disease (137) .…”

Through-Space Multinuclear Magnetic Resonance Signal Enhancement Induced by Parahydrogen and Radiofrequency Amplification by Stimulated Emission of Radiation

“…Inherently low sensitivity is seen as a significant limitation of NMR spectroscopy and imaging. The most efficient way to improve NMR sensitivity is to create nuclear spin hyperpolarization, i.e ., highly nonequilibrium population of the nuclear spin states. , At the moment, several hyperpolarization techniques are available, including dissolution dynamic nuclear polarization (d-DNP), − spin-exchange optical pumping (SEOP), − parahydrogen-induced polarization (PHIP), − and signal amplification by reversible exchange (SABRE). , d-DNP and SEOP are currently used for human biomedical applications with astounding results. ,− However, d-DNP and SEOP require sophisticated and expensive equipment limiting their widespread use and suffer from the long time needed for production of a hyperpolarized (HP) sample and the low duty cycles. In contrast, PHIP and SABRE are the faster and more affordable alternatives.…”

Standalone portable xenon-129 hyperpolariser for multicentre clinical magnetic resonance imaging of the lungs

“…Magnetic resonance imaging (MRI) of hyperpolarised xenon-129 ( 129 Xe) is an emerging research and clinical imaging modality, with demonstrated clinical impact in a range of lung pathologies such as cystic fibrosis, interstitial lung diseases, asthma and obstructive lung diseases. 1 Additionally, hyperpolarised 129 Xe MRI has been demonstrated in other organs (e . g .…”