Supporting powerful brain imaging research

11 September 2024

Last week, we announced the three researchers who will be funded under the first round of our Catalyst Awards. One of these researchers, Dr. George Gorrie of the University of Glasgow, intends to use powerful brain imaging techniques to peer inside the brains of people living with motor neuron disease (MND). In these brain scans, Dr. Gorrie will look for signs of disease progression called biomarkers.

In our Research Strategy, Catalysing a Cure, we said that improving translation of therapies that work in the lab but struggle to help people living with MND was one of our key strategic priorities. If Dr. Gorrie identifies biomarkers, they could serve two important purposes that align with this priority: accelerating diagnosis and dividing MND cases into subgroups.

The science of MRI

Dr. Gorrie will use magnetic resonance imaging (MRI) in his research. This technique has been an essential tool in neuroscience since its invention in the 1990s.

MRI works by altering subatomic particles called protons. These particles are present in all the atoms in our bodies. Inside an MRI scanner, protons are exposed to a powerful magnetic field. The scanner pulses waves of energy through this magnetic field, which in turn cause protons to fire out energy. By measuring this energy release, the MRI can determine the difference between various types of tissues in the brain. These differences can be shown in images produced by the scanner.

But not all MRI scanners are made equally. The more powerful the magnet in the scanner, the crisper the resulting images are. Dr. Gorrie will utilize a 7 Tesla (7T) scanner housed at the University of Glasgow’s Imaging Centre of Excellence (ICE) on the Queen Elizabeth University Hospital campus. Only a handful of sites in the UK can bring scanners of this strength to bear. The 7T scanner is many times more powerful than MRI machines used for routine clinical practice.

What’s being investigated?

Researchers can analyze data produced by MRI to explore different functions and structures in the brain. Dr. Gorrie will use the data to look at four key measures.

1. Iron in the brain: Previous MRI studies noticed darker-than-expected spots in the brains of people living with MND. These spots appear in the motor cortex, where motor neurons originate. Collectively called a “motor band sign”, these dark spots are thought to be caused by a buildup of iron in brain cells. If this buildup is caused by disease processes, then detecting a motor band sign may represent a useful diagnostic marker of MND. Importantly, this sign appears to only be detectable using the improved resolution offered by the 7T scanner.
   
   
2. The path of motor neurons: To reach muscles throughout the body, motor neurons form bundles of nerves and travel through a region called the corticospinal tract. These bundles are coated in a substance called myelin, which allows nerve signals to move quickly through the body. Dr. Gorrie intends to use a technique called diffusion tensor imaging to study the health of this myelin in people living with MND.
   
   
3. Brain metabolism: Our brain cells use and release tiny molecules during their everyday function – these are called metabolites. A technique called magnetic resonance spectroscopy, which relies on MRI data, can be used to measure changes in metabolites. Dr. Gorrie will look for metabolic changes that herald the breakdown of brain cells in the motor cortex.
   
   
4. Brain shrinkage: MND is closely related to a form of dementia called fronto-temporal dementia (FTD). Roughly one in seven people with FTD will go on to develop MND. Dr. Gorrie will use MRI to study the frontal cortex – where higher thinking happens in the brain and the site of FTD damage. This imaging will look for changes, like shrinkage, in this area. This could help researchers divide people living with MND into subcategories.

Why is this research helpful?

Dr. Gorrie will investigate whether data from the MRI scans will prove useful in diagnosing MND earlier. For some people, it can take over 12 months to receive a diagnosis of MND. In MND, every second counts and techniques that could quickly identify disease are greatly needed. This information could also be used to help divide people into subgroups depending on what is happening in their brain. This could help people access the treatments that are most likely to help them as quickly as possible.