National Facility of Imaging’s (NIF) Co-Director of the University of Sydney/ANSTO joint node, Professor Fernando Calamante, has been elected President of the International Society for Magnetic Resonance in Medicine (ISMRM). ISMRM draws on a multidisciplinary membership of over 9,000 clinicians, physicists, engineers, biochemists, and technologists who contribute to discovery, innovation and clinical translation in magnetic resonance.
Professor Calamante’s research is at the forefront of his field and includes the development of novel methods for Diffusion MRI, Perfusion MRI and brain connectivity, and their applications to neurology and neuroscience. He has gained international recognition for his MRI methods including his contribution to the MRtrix software for Diffusion MRI analysis, which is considered one of the most widely adopted tools in the field.
“I feel greatly honoured to have been elected to this role. The ISMRM has played such an important part of my research career and has been the source of so many collaborations and inspiration to my research; it is a real privilege to be able to play my part in contributing to ensuring the ISMRM continues to deliver its vision. These are challenging times, and it will be interesting to see how Societies such as ours react, adapt and evolve in the face of the challenges COVID has given us.” Professor Calamante said.
Professor Calamante is the first researcher from outside Europe or North America to be elected as ISMRM President.
“It is a great milestone for the ISMRM, and testimony of its international nature and diversity. Having come originally from Argentina and now living in Australia for the last 16 years, I feel I can fly the international flag as ISMRM President. As the first ‘rest of the world’ President, I will do my best to increase the presence of the ISMRM in under-represented regions,” Professor Calamante said.
Professor Calamante is the Director of Sydney Imaging, Core Research Facility at the University of Sydney and Professor in the School of Biomedical Engineering, Faculty of Engineering.
NIF Chief Executive Officer, Professor Graham Galloway said he was delighted that Professor Calamante was elected ISMRM president and has been recognised for his expertise in magnetic resonance. ISMRM is recognised by the MR community as the premiere organisation for sharing of discovery and applications and driving the development of MR technology. It brings together basic scientists, engineers, clinicians and industry. Professor Calamante’s election demonstrates that NIF is at the forefront of leading-edge imaging instrumentation and expertise in imaging technology.
The NIF Molecular Imaging & Radiochemistry (MIR) Theme is a group of NIF Fellows, Directors, and users of NIF facilities that focus on state-of-the-art radiochemistry and molecular imaging applications using PET, SPECT, and MRI.
Integrating preclinical PET systems into a national resource requires the development of defined QA programs to monitor and integrate the data from individual systems. Hence, the MIR Theme initiated a national quality assurance (QA) program for the NIF preclinical PET instruments.Read More
The Australian Government’s National Collaborative Research Infrastructure Strategy (NCRIS) exists to enable national-scale research facilities, thereby facilitating Australian researchers to address critical national and global challenges effectively and efficiently. NCRIS projects provide equipment, resources, analysis tools and, importantly, expertise.Read More
Magnetic Resonance Imaging (MRI) has a range of applications in medical diagnosis, and more than 25,000 scanners are estimated to be in use worldwide. However, lung imaging suffers from some technical challenges, limiting its application in pulmonary disease diagnosis and treatment.
Due to low proton density, movement and high susceptibility difference between air and tissue, conventional proton MRI struggles to image lung tissue and function. These can be partially overcome by the introduction of contrast agents into the lung. Hyperpolarised gases are promising contrast agents for imaging lung structure and function. The two most common gasses are helium (3He) and xenon (129Xe) isotopes. Helium isotopes are challenging and expensive to obtain, and do not provide significant functional readouts. Xenon can be challenging to work with, but promises novel physiological measurements not previously feasible. This resulting technique, termed hyperpolarized 129Xe MR imaging, has revolutionised the field of functional lung imaging.
Five years ago, an Australian Research Council (ARC) grant was awarded to researchers at Monash Biomedical Imaging (MBI) and ANSTO to design and build a machine that could reliably produce hyperpolarized xenon. In this project, Dr Wai Tung Lee and NIF Facility Fellow Dr Gang Zheng have teamed up to develop a new multimodal technology capable of high-quality investigations of the human lungs. While Dr Lee, of ANSTO, was responsible for the construction of the polarizer and production of polarized 129Xe for MR imaging, Dr Zheng, of Monash University, designed the MR experiments and adapted imaging protocols.
Hyperpolarized 129Xe (HP-Xe) gas was generated in a custom designed and constructed SEOP system at Monash Biomedical Imaging (Figure 1 and Figure 2). The system consists of a gas-polarizing unit and a gas injection and recycle unit. The core component of the gas-polarizing unit is an optical pumping cell (OPC) where the gas is polarized. The OPC is placed in an oven to regulate the amount of Rb vapour by maintaining a constant temperature between 60ºC-90ºC. The optical pumping process uses two 240W narrow-bandwidth lasers tuned to the Rb D1 transition wavelength of 794.7nm. Additional optics condition the laser light to circular polarization and shape the laser profile to fully illuminate the OPC. HP-Xe is produced in batches rather than using a continuous-flow process.
MR experiments were performed on a clinical 3T whole-body system (Skyra, Siemens Medical Solutions, Erlangen, Germany) with a broadband RF amplifier. HP-129Xe MRI was enabled using a bird-cage transmit/receive chest coil (RAPID Biomedical GmbH, Wuerzburg, Germany). A 2D-GRE sequence for X-nuclei MRI was used to image HP-Xe gas in lung. Proton channel images were acquired for the localization of the lung. The resonance frequency of 129Xe was set to 34.09 MHz on the 3T scanner. The human subject first quickly flushed his lung with pure nitrogen, and then immediately inhaled HP-Xe in the Tedlar bag. After inhalation of HP-Xe, the subject held their breath during the scan. The total imaging time was less than 10s.
Dr Zheng outlines the results to date, “We have successfully imaged gas-phase HP-129Xe in a range of phantoms, such as the Tedlar bag, syringe and the glass cell (Figure 3). We repeated the gas-phase imaging in both ex-vivo (Figure 4) and in-vivo lamb lungs (Figure 5). Imaging results supported that our polarizer can provide sufficient polarization for lung imaging. In 2019, we successfully performed a human experiment and a gas signal from the lungs was clearly identified (Figure 6). In addition, all studied showed a clear Rf peak of gaseous and dissolved xenon which should allow us to develop methods to assess lung function. We plan to study human pulmonary disease in the near future and hope to find additional collaborators to help translate this modality into clinical use.”
Gallery Notice : Images have either not been selected or couldn't be found
Construction of the hyperpolarizer is complete; it can routinely produce HP-129Xe for research use. The technique has successfully imaged HP-129Xe in phantoms, ex-vivo and in-vivo lamb lungs and a human lung. If you are considering lung research, please see more on the Monash website, or get in touch with Dr Gang Zheng to discuss your project needs.
Zheng G, Lee WT, Tong X, et al., A SEOP Filling Station at the Monash Biomedical Imaging Centre. Conference on polarization in Noble gases (PiNG), 2017.
Zheng G, Lee WT, Tong X, et al., Phase imaging of hyperpolarized 129Xe gas in a human lung. ISMRM 2020, submitted on 6 Nov 2019.
National Imaging Facility, ARC (Grant LE130100035); NHMRC (Grant APP606944); CASS Foundation; Monash Biomedical Imaging, ANSTO
This story was contributed by Dr Gang Zheng of the Monash University NIF Node.