New technique enables researchers to image the brain more accurately

Quantitative susceptibility map of human brain.

Diseases and injuries of the brain have a magnetic quality that can indicate the degree of damage to the brain. For physicist and brain health researcher Dr. Alex Rauscher, making sense of the brain’s magnetic field is a complex equation, but one with the promise to objectively measure deterioration and tissue repair.

Quantitative susceptibility mapping (QSM) is a relatively new technique developed by physicists to map the magnetic properties of brain tissue via magnetic resonance imaging (MRI). A recent paper in the journal NeuroImage from Dr. Rauscher’s team presented a new method for QSM which speeds up reconstruction and improves on current state-of-the-art methods. QSM allows researchers to image the brain in greater detail, and can be used in conjunction with other imaging methods, such as myelin water imaging, to provide a more complete picture of brain health or disease. 

In 2005, Dr. Rauscher was among the first to demonstrate that mapping the magnetic field improves imaging of iron-rich areas of the brain, as well as tissue affected by trauma and diseases such as multiple sclerosis (MS), Alzheimer’s disease, and Parkinson’s disease. In 2013, his physics graduate student Vanessa Wiggermann showed that the formation of multiple sclerosis lesions leads to large changes in the magnetic properties of brain tissue

“We were the first to establish some of the early criteria for QSM,” Dr. Rauscher says. “While other groups had made great progress, it was clear that the technique still needed considerable improvement.” 

Engineering physics student in Christian Kames joined Rauscher's team as an undergraduate co-op student in 2015. Kames, now a graduate student in Rauscher’s lab, focused on improving QSM in terms of speed and image quality.  

In 2016, Kames won an international award for creating the best QSM method. Due to its high sensitivity, the method promises to become a marker for tissue damage and repair in the central nervous system.

“This is important technology, enabling UBC researchers to do more precise brain imaging,” says Rauscher, who is currently involved in studies with a number of scientists in Djavad Mowafaghian Centre for Brain Health clinics.

“With QSM, we can track changes in the brain with high precision,” Rauscher says. The technique has the potential to reduce the cost and timeline for testing the efficacy of MS drugs in clinical trials. “When you’re able to map repair in MS, you get objective data that shows whether a drug is or isn’t working.”