Hyperpolarized Gas MRI for Pulmonary Disease Assessment
Polarean Imaging, a company based in North Carolina, is pursuing regulatory approval for clinical use of its hyperpolarized gas MRI. The technology is intended to assist in diagnosing respiratory conditions, something that would be particularly useful during the ongoing COVID-19 pandemic.
Specifically, Polarean produces equipment to generate hyperpolarized 129Xenon (HPX) or helium gas. In practice, the patient inhales some of the hyperpolarized gas, and then undergoes a 10-20 second MRI scan. Data published to date about the technology suggests that HPX MRI can enhance the MRI signal by 100,000-fold.
Such an enhanced signal may make it possible to non-invasively study lung structures in unprecedented detail, something that is not really possible with MRI alone. For instance, it may be possible to identify areas of the lung with poor ventilation, and quantify the volume of ventilated space within the lungs. In effect, such measurements allow clinicians to image lung function rather than just lung structure.
Medgadget had the opportunity to talk to Richard Hullihen, Chief Executive Officer of Polarean Imaging, about the technology and what it may mean for clinical practice.
Conn Hastings, Medgadget: Please give us an overview of MRI scanning in assessing respiratory diseases.
Richard Hullihen, Polarean Imaging: MRI is presently not widely used in respiratory disease assessment. This is because historically proton-based MRI is tuned to find water in tissues and as the lungs are filled with air, the signal gets attenuated and the resulting resolution has not been very useful. When combined with Polarean’s drug device, it shows promise to become a key tool in the assessment of respiratory disease, by using Xenon instead.
Medgadget: How has magnetic resonance imaginging played a role in the response to the COVID-19 pandemic?
Richard Hullihen: Most healthcare institutions have reduced staff and caregiving during the pandemic. Because COVID-19 is an infectious disease, patients and staff are very carefully controlled and very few leave the designated areas and ICUs where they are being cared for. Due to the limited utility of proton-based MRI as mentioned above, MRI hasn’t been used frequently as a tool for imaging the lung in the acute setting. We look in the future toward research focused on post-infection effects of COVID-19 on pulmonary function and helping pulmonary medicine in assessing this.
Medgadget: How does hyperpolarized gas MRI work? What are its advantages compared with conventional MRI?
Richard Hullihen: Hyperpolarization of our inert noble gas contrast agent 129Xenon creates an inhalable contrast agent with a 100,000-fold increase in signal. This allows for the visualization of ventilation to the endpoints of airways, and the regional assessment of gas exchange and lung function in a single 10 second breath hold scan. It does this without exposing the patient to ionizing radiation inherent in x-ray or CT procedures.
Medgadget: Please give us an overview of the products offered by Polarean Imaging.
Richard Hullihen: Polarean offers its drug device combination products in the form of its HPX Polarizer and QA measurement station, its drug delivery device which is a single use bag with mouthpiece, and its proprietary drug, the 129Xenon source gas blend.
Medgadget: What types of diseases can be assessed using hyperpolarized gas MRI?
Richard Hullihen: As you know, we are operating in a research mode presently, pursuing our first FDA approval. As a result, we are not able to make claims regarding our technologies use in clinical medicine per se. Our research customers who use the system routinely are studying virtually every form of pulmonary disease including asthma, cystic fibrosis, COPD, interstitial lung disease, and most recently pulmonary vascular disease.
Medgadget: Has the technology been used during the COVID-19 pandemic so far?
Richard Hullihen: Neither we nor or investigators from our installed base research institutions have yet published peer reviewed articles on the use of our technology in COVID-19, yet. As we previously mentioned, because this technology can directly measure function deep in the lung, non-invasively, researchers are interested in assessing its utility to characterize the long-term sequelae arising from virus-induced alveolar damage.