1. Office of Public Health Ansgar Furst, Ph.D. Director of Neuroimaging Laboratory, WRIISC VA Palo Alto, CA Clinical Assistant Professor (Affiliated) of Psychiatry and Behavioral Sciences and of Neurology and Neurological Sciences Stanford University School of Medicine, CA DTI as a promising tool for a deeper understanding of white matter pathology

2. Office of Public Health Neuroimaging- What else?  Diffusion Tensor Imaging (DTI)  F-MRI  Diffusion-Weighted Imaging  Diffusion-Spectrum Imaging  Magnetic Resonance Spectroscopy  Magnetization Transfer Imaging  Magnetic Source Imaging

3. Office of Public Health Neuroimaging- What else?  Diffusion Tensor Imaging (DTI)  F-MRI  Diffusion-Weighted Imaging  Diffusion-Spectrum Imaging  Magnetic Resonance Spectroscopy  Magnetization Transfer Imaging  Magnetic Source Imaging

4. Too many imaging sequences ?

5. Office of Public Health Broad classification scheme T1-weighted T2-weighted T2-FLAIR T2*-GRE SWI DTI fMRI PET StructureFunction

6. Office of Public Health Broad classification scheme StructureFunction Mass effects Volume changes Midline shifts

7. Office of Public Health Broad classification scheme Structure Mass effects Volume changes Midline shifts

8. Office of Public Health Broad classification scheme Function Stay tuned …

9. Office of Public Health Diffusion Tensor Imaging (DTI)  MR sequence (available since the 90s) relatively simple to implement and time efficient  Measures microscopic motion of water molecules in brain tissue  Gives an indirect account of integrity & connectivity of white matter fiber tracts

10. Office of Public Health How does it work ?

11. Office of Public Health How does it work ?

12. Office of Public Health

13. Soaker hose analogy

14. Office of Public Health Soaker hose analogy

15. Office of Public Health FA maps – no sense of direction

16. Office of Public Health Tensors code direction of movement

17. Office of Public Health (Directionally) colored FA maps Anterior Posterior LeftRight Superior Inferior

18. Office of Public Health Patient 014  32-year old OIF veteran  Blow to the head with LOC ~ 2 min, additional LOC in bar fight and motor cycle accident < 1 min  Was in vicinity of numerous mortar blasts – no LOC but confused about circumstances afterwards  Patient complains about severe headache  Was diagnosed with TBI during WRIISC visit

19. Patient 014

25. Office of Public Health DTI – just pretty pictures ?  DTI imaging (particularly fiber tracking) can be a very powerful tool in identifying otherwise unnoticed white matter compromises  However, customized fiber tracking is very time consuming and difficult to automatize as each patient’s fiber tract architecture is unique  In order to be useful to clinicians more easily interpretable, reliable quantification of white matter damage is needed

26. Office of Public Health Please come and visit us at our poster! DTI – towards a diagnostic tool

27. Office of Public Health Suggested reading If you want to learn more about DTI Recent data showing superior sensitivity of DTI in detecting TBI

28. Office of Public Health THANK YOU!