The arrows show the direction and amplitude of the brain’s movement. These displacement patterns, which were enabled by extra processing of 3D aMRI, may help us understand how the brain moves with different disorders. 3D aMRI method outlined in Abderezaei et al. Brain Multiphysics (2021); Terem et al. Magnetic Resonance in Medicine (2021).
“The new method magnifies microscopic rhythmic pulsations of the brain as the heart beats to allow the visualization of minute piston-like movements, that are less than the width of a human hair,” explained Itamar Terem, a graduate student at Stanford and lead author of the first paper. “The new 3D version provides a larger magnification factor, which gives us better visibility of brain motion, and better accuracy.”
3D aMRI of the human brain shows minute movements of the brain at an unprecedented spatial resolution of 1.2 mm3, approximately the width of a human hair. The actual movements are amplified (made larger, up to 25 times) to allow clinicians and researchers to view the movements in detail. The striking detail of these animated magnified movements may be able to help identify abnormalities, such as those caused by blockages of spinal fluids, which include blood and cerebrospinal fluid.
“We showed that 3D aMRI can be used for the quantification of intrinsic brain motion in 3D, which implies that 3D aMRI holds great potential to be used as a clinical tool by radiologists and clinicians to complement decision making for the patient’s treatment,” said Kurt, senior author of the second paper. “In my lab at Stevens, we are already seeing the benefits of using variants of 3D aMRI technique in a variety of clinical conditions including Chiari Malformation I, hydrocephalus, and aneurysms, in collaboration with clinicians at Mount Sinai.”
A number of research projects are underway using the new imaging software. Holdsworth said: “We are using 3D aMRI to see if we can find new insights into the effect of mild traumatic brain injury on the brain. She added: “One study already underway, a collaboration between Mātai and the University of Auckland, uses 3D aMRI together with brain modelling methods to see whether we can develop a non-invasive way of measuring brain pressure, which may in some cases remove the need for brain surgery”. This could be valuable clinically, for example, in children with idiopathic intracranial hypertension who often require invasive brain pressure monitoring.
Miriam Sadeng, an associate professor at the University of Auckland in the department of anatomy and medical imaging, who is a physician and is an author on both papers, said: “This fascinating new visualisation method could help us understand what drives the flow of fluid in and around the brain. It will allow us to develop new models of how the brain functions, that will guide us in how to maintain brain health and restore it in disease or disorder.”
“Validating the method through computational modelling gave us further confidence about the potential impact of this work,” said Javid Abderezaei, a graduate student in Kurt’s lab at Stevens and lead author on the second paper. “What is exciting to see is that the dominant displacement patterns in the healthy brain qualitatively matched with the underlying physiology, which means that any changes in the physiological flow as a result of a brain disorder should be reflected in the displacements we measure.”
The capability to view the differences in brain motion could help us better understand a variety of brain disorders. In the future, the technology could be expanded to use in other health disorders throughout the body.