SPMIC Seminar
Speakers : Arthur Harrison (University of Nottingham) and Dr Nikita Sushentsev (University of Cambridge)
Title part 1 : Hyperpolarisation development: Large scale gas separation via catalytic combustion. (Arthur Harrison) Time : 13:00 Abstract: Noble gases as contrast agents for pulmonary MRI is a rapidly developing field. Spin exchange optical pumping (SEOP) is used to artificially increase the spin polarisation of these gasses, allowing for fast detection in NMR studies. However, this process requires dilution with a buffer gas which, if not removed, reduces observed signal intensities. Modern methods employ a nitrogen buffer gas; however, cryogenic separation techniques can serve a significant penalty to the spin polarisation. Previous work demonstrated the feasibility of using a hydrogen buffer gas, capable of oxidative removal during the purification process. The second-generation combustion system is capable of separating large volumes of post SEOP gas mixtures, before recompression to ambient pressure. This process takes as little as 15 seconds, minimising signal loss due to polarisation decay. Additionally, this is currently the only viable purification method for hyperpolarised krypton, due its electric quadrupole. Title part2: Magnetic resonance fingerprinting of prostate cancer: translational potential and technical challenges (Dr Nikita Sushentsev) Abstract: Facilitating clinical translation of quantitative imaging techniques has been suggested as a means of improving interobserver agreement and diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) of the prostate. One such technique, magnetic resonance fingerprinting (MRF), has significant competitive advantages over conventional mapping techniques in terms of its multi-site reproducibility, short scanning time, and inherent robustness to motion. MRF has been shown to improve the detection of clinically significant prostate cancer when added to standard mpMRI sequences, however, several fundamental questions still require answers before adding MRF to mpMRI to investigate its diagnostic utility in the clinical setting. For instance, mpMRI protocol mandates the inclusion of dynamic contrast enhanced (DCE) imaging, known for its significant T1 shortening effect. MRF could be used to measure both pre- and post-contrast T1 values, but its utility must be assessed. Moreover, the existing studies using MRF in the prostate have all been conducted on 3.0 T MRI systems, limiting the technique’s use on 1.5 T MRI scanners that are still more widely used for prostate imaging across the globe. In my presentation, I will, therefore, discuss the results of our study in which we evaluated the variation in MRF T1 measurements post gadolinium-based contrast agent injection and the utility of such T1 measurements to differentiate peripheral and transition zone tumours from normal prostatic tissue. I will also present our work focussed on evaluating the cross-system reproducibility of prostate MRF T1 using 1.5 and 3.0 T MRI systems. Finally, I will outline forward-looking ideas related to the use of prostate MRF in the clinical setting and will be open to discuss any potential collaborations on improving its technical aspects