Exploring MRI at a Deeper Level

WSU researchers are transforming the common MRI technique to glean unprecedented insights into human tissue.

Cancer is a leading cause of death with over 14 million new cancer cases occurring each year worldwide. A significant proportion of the global burden of this devastating disease can be prevented by early detection and treatment of primary tumours.

Cancer patients around the world are likely to benefit from new diagnostic tools being developed at Western Sydney University. Invasive and risky biopsies are routinely used to diagnose cancer. But these could be replaced by a ‘virtual biopsy’ generated from safe MRI scans once the research of the Nanoscale Organisation and Dynamics Group at Western Sydney University is broadly adopted. A virtual biopsy would acquire enough information from an MRI scan to be able to identify the tumour, categorise it as benign or malignant and provide, ideally, all the information that can be acquired from a traditional physical biopsy but in a non-invasive manner.

And it doesn’t stop there. The group’s imaging skills are already helping brain disease researchers, environmental chemists, grape growers and geologists searching for minerals.

“This system is incredibly versatile, we can tackle just about anything you can think of,” says the group’s leader, Professor Bill Price.

“Whether it’s a grape berry, brain tissue or sandstone, it’s a porous medium — liquid contained in a cavity — so from an MRI perspective there’s not a huge difference.”

The group is a node of the National Imaging Facility (NIF), which has put them in contact with diverse groups of researchers. The group boasts a range of skills, from fundamental quantum physics, through to clinical experience, and with this breadth of knowledge, they have developed ways to extract more data from magnetic resonance scans. 

Need to know

  • WSU research has improved MRI scans
  • This can be used in early cancer detection
  • It also has industrial applications

They have developed MRI techniques, known as pulse sequences, to extract specific information, or in some cases suppress unwanted effects, says Dr Tim Stait-Gardner, a NIF fellow who’s part of the group.

“If a sample is dissolved in water there’s a huge water signal that obscures the molecules of interest. We have developed techniques to remove the water signal so we can see traces of compounds such as brain metabolites,” he says.

The group’s water suppression pulse sequence is so effective that it has been included as a standard sequence by a major MRI manufacturer, Bruker.

Another strength is the group’s ability to not only identify the molecules in a sample, but to measure their motion, a property called diffusion. The new parameter could assist in cancer diagnosis, says Price.

“Standard MRI measures the concentration of molecules, so it might not pick up a brain tumour, for example. Because the tumour cells might have a different internal viscosity than normal cells, with a diffusion filter you might be able to achieve good contrast between the normal tissue and the tumour.”

The technique may even be able to identify parts of a tumour that are low in oxygen, a crucial breakthrough, as this hypoxic tissue is more resistant to radiotherapy treatment.

In addition to diagnosis, Dr Abhishek Gupta, a postdoctoral researcher, is working with nearby Liverpool Hospital to improve cancer treatment by combining their innovative MRI scans with radiotherapy to recommend more precise dosage. “You want to be able to see the fine boundaries of the tumour to make sure you treat all of it without damaging healthy tissue,” Gupta says.

Gupta is also developing advanced MRI-contrast agents which can be injected into the body to improve the clarity of tumour images and enable accurate disease diagnosis and management.

Price believes the techniques will have a huge impact. “The developments in the field have been enormous. Ten years ago, what we’re doing now was science fiction,” he says. 

What is MRI?

Magnetic Resonance Imaging (MRI) is performed by a giant elongated doughnut-shaped magnet in hospitals in which patients must lie very still. A ‘pulse sequence’ uses radio-frequency pulses of electromagnetism to interrogate the hydrogen atoms in the relevant tissue or sample to generate a signal, which is reconstructed by computer to create an image. Because different tissues modulate the signals differently, a detailed picture can be assembled. MRI’s advantage is that it is biologically safe, it can image soft tissue and in some cases, video can be created from the imaging.

Meet the Academic | Professor Bill Price

Professor William S. Price leads the Nanoscale Organisation and Dynamics Research Group, is the chair of Medical Imaging Physics in the School of Science and Health, and a Conjoint Professor in the School of Medicine at Western Sydney University. He is the Director of the Biomedical Magnetic Resonance Facility and of the University’s node of the National Imaging Facility, an Adjunct Professor at the National Wine and Grape Industry Centre at Charles Sturt University and holds an honorary appointment in Medical Physics at the Liverpool and Macarthur Cancer Therapy Centres.

Professor Price completed his PhD (1990) and DSc (i.e., higher doctorate; 2012); both at the University of Sydney. He is a Fellow of the Royal Society of Chemistry, the Royal Australian Chemical Institute and the Australian Institute of Physics. His research has resulted in numerous awards including the RACI’s Rennie Memorial Medal. His research interests include probing molecular dynamics in biological (e.g., tumours) and chemical systems using magnetic resonance measurements of translational diffusion and relaxation, and MRI technique and contrast agent development.

Credit

©  Nanoscale, Western Sydney University © anilyanik / Getty
Future-Makers is published for Western Sydney University by Nature Research Custom Media, part of Springer Nature.