How is diffusion tensor imaging done?
The analysis of water diffusion is performed by applying magnetic field gradients to generate an image that is sensitized to diffusion in a particular direction. A three-dimensional diffusion model (the tensor) is then estimated by repeating this process in multiple directions.
What is DTI imaging used for?
Diffusion tensor imaging tractography, or DTI tractography, is an MRI (magnetic resonance imaging) technique that measures the rate of water diffusion between cells to understand and create a map of the body’s internal structures; it is most commonly used to provide imaging of the brain.
What does diffusion tensor imaging detect?
Diffusion Tensor Imaging (DTI) is a technique that detects how water travels along the white matter tracts in the brain (Fig. 2). White-matter tracts connect different parts of the brain and must be protected during surgery.
What does red color indicate in DTI map?
A standard color scheme was used in the BrainLAB software to encode the FA maps, with blue indicating superior–inferior, red indicating transverse, and green indicating anterior–posterior.
How much does a DTI scan cost?
Results: The total direct costs of DTI and MR tractography for a 1.5-T system with 15 encoding directions were US $97. Variable cost was $76.80 and fixed cost was $20.20.
Does fMRI use contrast?
The primary form of fMRI uses the blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa in 1990. Since the early 1990s, fMRI has come to dominate brain mapping research because it does not require people to undergo injections or surgery, to ingest substances, or to be exposed to ionizing radiation.
Who created DTI?
The diffusion tensor was originally proposed for use in magnetic resonance imaging (MRI) by Peter Basser in 1994 [5, 6].
How long is diffusion tensor imaging?
between 5 and 10 min
To acquire DTI data covering the entire brain with high and reliable quality, a sequence takes between 5 and 10 min, which is relatively long compared to structural sequences such as T1-weighted and T2-weighted sequences.
What do the colors mean on a DTI?
4.2 Colors derived from DTI The color scheme most commonly used to represent the orientation of the major eigenvector works as follows: blue is superior-inferior, red is left-right, and green is anterior-posterior [48]. The cingulum can be seen in blue, and the posterior limb of the internal capsule in green.
What do the colors on a DTI image represent?
When RGB is set the DTI vectors are expressed by colours where Red, Green and Blue represent the x,y and z diffusion directions respectively. Colours such as purple are mixes of red, green and blue and therefore express vectors that have significant nonzero components in more than one of the x,y,z directions.