Diffusion MRI Flashcards
The ability of molecules to move across available space is known as:
Diffusion
Mean diffusivity refers to:
The overall diffusion
A brain imaging technique responsible for “tracing” the location & direction of white matter is:
Tractography
What allows for distinction between healthy & unhealthy white brain matter in older individuals?
White matter integrity
The dense, white matter that connects both hemispheres of the brain is called the _____ _____:
Corpus callosum
_____ are the “communicators” of the brain
Neurons
Neurons are made up of which 4 properties?
Axons, axon terminals, cell bodies & dendrites
Magnetic resonance imaging (MRI) helps identify ____ ____ in the brain:
Neural activity
Diffusion MRI’s can measure axon size & density & individual fibres. True or false?
False - they are unable to measure any of those
Diffusion MRI can be beneficial for providing information about axonal directions in white matter, microstructure (in voxels) & white matter integrity. True or false?
True
Yang et al. (2017) investigated what in subjects with & without trigeminal neuralgia?
White matter integrity
One limitation of using diffusion MRI is that they are sensitive to:
Fast imaging artefacts
It is difficult for diffusion MRI to deal with crossing/”kissing” fibres, and more restricted by scanner hardware. True or false?
True
Which 2 techniques are complimentary to diffusion MRI?
Tracer studies, histology
In which neuroimaging technique is dye injected into neurons to allow for finer details to be seen?
Tracer studies
____ refers to the relationship between two variables:
Correlation
____ refers to one variable causing changes in another:
Causation
One difference between structural & diffusion MRI is that structural MRI has a resolution of ____ mm, whereas diffusion MRI has a resolution of ____mm:
1; 1-3
Structural MRI is able to segregate _____ matter, ____ matter and ______ ____:
white; grey; cerebrospinal fluid
Structural MRI takes longer to acquire images than diffusion MRI. True or false?
True
Name the key properties of diffusion MRI:
Distorted images, several images able to be taken at once, lower resolution
Diffusion MRI takes less time, but produces more distorted images. True or false?
True
There is no principle diffusion direction in _____ matter, thus diffusion MRI is mostly used when looking at ____ matter:
Grey; white
Diffusion MRI can provide a _____, ______ and _____ view of the corpus callosum:
Dorsal; sagittal; coronal
True or false: the ability of molecules to diffuse is constrained by boundaries and depends on the direction upon which they are travelling:
True
Water is best at diffusing ____ axons, but not _____:
Along; sideways
Diffusion MRI can be used to study various brain disorders, by generating contrast in the movement (diffusion) of water in _____ matter and telling us which direction the _____ are going:
White; axons
