LIFT: Lung magnetic resonance Imaging of Fluorocarbon Tracer gases
Research type
Research Study
Full title
Lung magnetic resonance Imaging of Fluorocarbon Tracer gases
IRAS ID
211398
Contact name
John Simpson
Contact email
Duration of Study in the UK
2 years, 10 months, 14 days
Research summary
Summary of Research
In this study we will develop and implement new methods for safe, repeatable, non-invasive imaging of lung ventilation properties. We will develop a technique to image gases in lungs using an MRI scanner. The study has three phases: technical development work, healthy volunteer repeatability studies, and studies of patients with a respiratory disease. All three phases of the study involve participants inhaling an inert gas (a fluorocarbon gas called perfluoropropane) for a short period (up to 4 inhalation sessions, each up to 1 minute duration), which is inhaled as a perfluoropropane/oxygen gas mixture. Gas inhalation will be performed whilst study participants are lying in an MRI scanner, so that images can be acquired of gas entering and leaving the lungs over the respiratory cycle.
In the first phase of the study we will optimise our MRI scan methods. In the second phase we will measure the reproducibility of our lung function measurements, and in the third phase we will measure the difference in lung function between patients with asthma, patients with chronic obstructive pulmonary disease, and healthy volunteers. In addition, we will measure the change in lung ventilation properties when patients are administered a bronchodilator drug.
If successful, our study will lead to a novel lung imaging approach with potential to augment or replace existing lung ventilation measurements that do not provide anatomical data, or that involve the use of radioisotopes or ionising radiation.
Summary of Results
This study is called “Lung magnetic resonance Imaging of Fluorocarbon Tracer gases”. It was carried out by researchers at Newcastle University and The University of Sheffield. It was sponsored by the Newcastle Upon Tyne Hospitals NHS Foundation Trust. Funding came from the Medical Research Council.
The study required the participation of healthy volunteers and patients with respiratory diseases, and thus patients and members of the public were involved in undertaking the research. We involved members of the public and patients with respiratory diseases in the design of the study, through discussions of the proposed work at British Lung Foundation "Breathe Easy" patient support group meetings and the VOICENorth Research Support Group. This involvement provided advice and input into the structure of the study participant journey, and into the design of the participant information sheets.
The study took place in both Newcastle Upon Tyne and Sheffield. In Newcastle the study took place at The Newcastle Magnetic Resonance Centre which is part of Newcastle University and linked with the Newcastle upon Tyne Hospitals NHS Foundation Trust. In Sheffield the study took place at the University of Sheffield and Sheffield Teaching Hospitals NHS Foundation Trust. The study took place between 3/8/2016 and 2/9/2022.
This research was needed to develop and implement new methods for safe, repeatable, non-invasive imaging of lung ventilation properties. The hope was that this will lead to a new lung imaging approach, without the use of radiation, that delivers scans showing lung function. We plan further development of this new type of lung scan so that it can eventually be used routinely by NHS hospitals to inform patient care.
We developed a technique to image special gases in lungs using an MRI scanner. The study had three phases: technical development work, healthy volunteer repeatability studies, and studies of patients with a respiratory disease.
All three phases of the study involve participants inhaling an inert gas called perfluoropropane (PFP), which was inhaled mixed with oxygen. Study participants were asked to inhale three deep breaths of the PFP/oxygen gas mixture lying in an MRI scanner, and then hold their breath whilst a scan of the gas in their lungs was taken. This allowed us to look at where inhaled gas goes in the lungs, which lets us see and measure ventilation problems associated with lung disease.
The principal research question was whether lung ventilation properties, as measured by MRI of inhaled perfluoropropane, differ between patients with a respiratory disease and healthy volunteers. “Ventilation properties” means how well air moves in and out of the lungs. We also wanted to see if the technique could show a difference in patients with respiratory disease (asthma or chronic obstructive pulmonary disease (COPD)) before and after they inhaled salbutamol, which is a drug to open up their bronchial tubes (a bronchodilator). We also asked what was the best MRI scan protocol to be able to see and measure lung ventilation properties.83 healthy volunteers, 41 patients with asthma and 28 patients with COPD were recruited across both study sites. Healthy volunteers attended for one scan session. After written consent was obtained, a measure of their lung function was performed (spirometry) and they inhaled perfluoropropane/oxygen gas mixture whilst MRI scans were taken of their lungs.
Patients with either asthma or COPD attended for a “screening” session at least 24hrs before their scan session, during which written consent was obtained. They were asked to withhold any regular bronchodilator medications they were taking up to 24hrs before the scan session. When they attended for their scan session, spirometry was recorded and they had the same scan as the healthy volunteers. However, they were then given salbutamol, after which spirometry was recorded again and the scans were repeated.
Of the 41 patients with asthma recruited and screened, only 35 were able to proceed to the scan session. Of the 28 patients with COPD recruited and screened only 21 were able to proceed to the scan session.We were able to demonstrate a statistically significant difference in the amount of gas entering the lungs when comparing patients with asthma and healthy volunteers. We were also able to demonstrate statistically significant differences in the amount of gas entering the lungs when comparing patients with COPD with healthy volunteers. We were able to demonstrate that at least 10% less volume of the lungs was fully ventilated in patients with either asthma or COPD than in healthy volunteers. We were also able to demonstrate that the MRI scanning technique was reproducible, as repeated scans on the same individual gave very close results. We found we could show a clear response to treatment with a bronchodilator in patients with respiratory disease.
This study has helped us establish that this is a technique that can be used safely and reliably to give direct visual information about areas of a person’s lungs that are working well and those which are not. It has allowed us to develop further work looking at clinical problems in patients with lung disease.
We have already done some further research using this technique to allow us to image participant’s lungs repeatedly whilst they breathe PFP/oxygen gas and then room air, to measure how quickly the gas enters and leaves different parts of the lungs. We have also been awarded funding to develop the MRI scanner technology used in our lung scans, to make the scans more accurate and better able to detect lung abnormalities.This study has generated four medical journal publications so far, and a further publication with details of the patient group results is currently being written. Results from this study have been presented at national and international conferences.
REC name
North East - Newcastle & North Tyneside 1 Research Ethics Committee
REC reference
16/NE/0282
Date of REC Opinion
7 Oct 2016
REC opinion
Further Information Favourable Opinion