May2022

The University of Aberdeen are piloting the world’s only human sized field-cycling MRI scanner in patients with brain tumours.

Unlike clinical MRI which operates at a fixed static field strength of typically 1.5T, the field cycling MRI scanner changes rapidly between 0.001T and 0.2T during a scan. By acquiring images at a range of field strengths and timings, we can measure the variation of T1 relaxation time (time for spins to return to equilibrium after excitation) with magnetic field. It is hoped that this will reveal protein interactions which may better characterise brain tumours.

We are currently recruiting pre-operative meningioma and low-grade glioma patients and comparing their field cycling scans and multi-field T1 maps with the post-operative pathology. The figure shows brain scans from a patient with a low grade glioma (diffuse astrocytoma, grade 2) in the right frontal lobe. The top row of the image shows conventional imaging (CT and 1.5T MRI) and a 200 mT research image showing hypointense signal within the brain tumour area. The bottom row shows maps of T1 relaxation times at five magnetic field strengths with the T1 measured in ms. The tumour exhibits longer T1 relaxation times than the normal brain across fields (shown in yellow).

The research team members are Lionel Broche, Vasiliki Mallikourti, James Ross, Minimol Paulose, Nichola Crouch, Stacey Dawson and Arnab Rana, with David Lurie in an Emeritus role.