fiber tracking techniques in magnetic resonance diffusion tensor imaging grace michaels csun,...
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![Page 1: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/1.jpg)
Fiber Tracking Techniques in Magnetic Resonance Diffusion
Tensor Imaging
Grace MichaelsCSUN, Computer Science
Junior
![Page 2: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/2.jpg)
What is MRDTI ?
• A modern technique for visualization at high resolution of the white matter tracts in the brain.
![Page 3: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/3.jpg)
Two Steps…
![Page 4: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/4.jpg)
MRI scanner, determines the orientation of the tracts at each point by measuring diffusion
rates and identifying the direction of the fastest diffusion.
![Page 5: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/5.jpg)
The information about the diffusion rates is encoded into the
diffusion tensor and various integration techniques are used to reconstruct the path of the fiber.
![Page 6: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/6.jpg)
DT-MRI also promises tofurther our understanding
of abnormalities in a variety of diseases such as
• Stroke • Tumors
• Multiple sclerosis • Schizophrenia
![Page 7: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/7.jpg)
Experiments
• 2D • 3D
![Page 8: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/8.jpg)
Experiments
• 2D
![Page 9: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/9.jpg)
Experiments
• 2D
![Page 10: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/10.jpg)
Experiments
• 2D
![Page 11: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/11.jpg)
How the method works?
• We start from initial concentration of test liquid, corresponding to a drop at some point of the tested media.
![Page 12: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/12.jpg)
How the method works?
• The fact that water molecules are more likely to propagate along the fiber then cross it is reflected in the coefficients of diffusion tensor prescribing different rates of propagation in different directions trough the linear diffusion equation.
![Page 13: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/13.jpg)
Diffusion Tensor
![Page 14: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/14.jpg)
where is concentration of test molecules at point
- one step forward in time - one step backward in time
),(),(3
1
3
1
txdx
dT
dx
dtx
dt
d
jij
i j i
),( tx 3x
So, we solve the anisotropic equation:
![Page 15: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/15.jpg)
A curvature-based ridge-tracking algorithm
in 2D
![Page 16: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/16.jpg)
Finding end points
![Page 17: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/17.jpg)
Finding end points
![Page 18: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/18.jpg)
Why is fiber tracking important?
• Brain surgery may cause damage to important fiber bundles. Knowledge of their extension could minimize functional damage to the patient.
• White matter can be visualized using fiber traces for a better understanding of brain anatomy.
• Connectivity between different parts of the brain can be inferred, which is useful for functional and morphological research on the brain.
![Page 19: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/19.jpg)
Future work
• Develop 3D experiments
• Get real data from MRI clinic in Pasadena
• Real data experiments
![Page 20: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/20.jpg)
Acknowledgements
• Dr. Alexander Alekseenko, Math Department, CSUN
• NASA CSUN/JPL PAIR Program
• Dr. Carol Shubin, NASA CSUN/JPL PAIR Program director, Math Department
![Page 21: Fiber Tracking Techniques in Magnetic Resonance Diffusion Tensor Imaging Grace Michaels CSUN, Computer Science Junior](https://reader030.vdocument.in/reader030/viewer/2022032523/56649d765503460f94a5825d/html5/thumbnails/21.jpg)
THANK YOU!
QUESTIONS ???