Office of Public Health Ansgar Furst, Ph.D. Director of Neuroimaging Laboratory, WRIISC VA Palo Alto, CA Clinical Assistant Professor (Affiliated) of Psychiatry.

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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

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Neuroimaging- What else?

Diffusion Tensor Imaging (DTI) F-MRI Diffusion-Weighted Imaging Diffusion-Spectrum Imaging Magnetic Resonance Spectroscopy Magnetization Transfer Imaging Magnetic Source Imaging

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Neuroimaging- What else?

Diffusion Tensor Imaging (DTI) F-MRI Diffusion-Weighted Imaging Diffusion-Spectrum Imaging Magnetic Resonance Spectroscopy Magnetization Transfer Imaging Magnetic Source Imaging

Too many imaging sequences ?

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Broad classification scheme

T1-weighted

T2-weightedT2-FLAIRT2*-GRE

SWI

DTIfMRIPET

Structure Function

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Broad classification scheme

Structure Function

Mass effects Volume changesMidline shifts

Altered synaptic/

metabolic activity, network

connectivity

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Broad classification scheme

Structure

Mass effects Volume changesMidline shifts

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Broad classification scheme

Function

Stay tuned …

Altered synaptic/

metabolic activity, network

connectivity

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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

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How does it work ?

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How does it work ?

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Soaker hose analogy

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Soaker hose analogy

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FA maps – no sense of direction

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Tensors code direction of movement

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(Directionally) colored FA maps

Anterior

Posterior

Left Right

Superior

Inferior

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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

Patient 014

Patient 014

Patient 014

Patient 014

Patient 014

Patient 014

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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

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Please come and visit us at our poster!

DTI – towards a diagnostic tool

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Suggested reading

If you want to learnmore about DTI

Recent data showingsuperior sensitivity ofDTI in detecting TBI

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THANK YOU!