Collaborations with theCollaborations with theUCLA Laboratory of Neuro UCLA Laboratory of Neuro

Imaging (LONI) Imaging (LONI)

Paul Thompson, Ph.D.

Professor of Neurology & Psychiatry

Director, Imaging Genetics Center

Laboratory of Neuro Imaging

UCLA School of Medicine, Los Angeles, CA

UCLA-CMRR were awarded 2 UCLA-CMRR were awarded 2 Collaborative R01s – only possible Collaborative R01s – only possible

because of the P41 – expertise, because of the P41 – expertise, infrastructure infrastructure

CMRR provides UCLA with novel scans, algorithms, analyses that we work on together (>30 papers in 4 years):

R01 NIBIB, HARDI Mapping of Disease Effects on the Brain - $549,204/year How can HARDI advance the study of Alzheimer’s disease?

- develop new algorithms to handle HARDI, multi-shell DWI (compute ODFs, tracts, networks)

- do better diffusion models help? (HARDI, TDF, CSA-ODF) and connectivity – CMRR expertise in mathematics as well as acquisition

Joint papers – with G. Sapiro (30 papers); C. Lenglet (26); Bryon Mueller (8), N. Harel (8); E. Yacoub (2), etc.

22ndnd R01 (UCLA/CMRR) – R01 (UCLA/CMRR) – Compare 7T and 3T Diffusion Compare 7T and 3T Diffusion

Imaging Imaging in Alzheimer’s disease, MCIin Alzheimer’s disease, MCI

• R01 NIBIB, Computational Modeling of High-Field MR Images - $294,831/year

• Scan 80 people at both 7T and 3T (Kelvin Lim and Bryon Mueller) – highly valuable dataset for the field

1. How can 7T scanning advance the study of AD and MCI?

2. How do DTI measures change at higher field? (FA/ODFs, networks, connectivity measures)

CMRR 7T DWI - Noam Harel; UCLA tractography

CMRR 7T DWI - Noam Harel; UCLA tractography

CMRR 7T DWI; Thompson-Lenglet-Sapiro R01

7T picks up thinner tracts; reconstruction method also matters

Connectivity matrices

10 people scannedat both 7 and 3T

Data reconstructed

with sum-of-squares,adaptive recombine,

SENSE1, etc.

Structural Network Structural Network Hubs Damaged by HIVHubs Damaged by HIV

Hough Transform Tractography AlgorithmAganj I, Lenglet C, Jahanshad N, Yacoub E, Harel N, Thompson PM, Sapiro G (2011).

A Hough Transform Global Probabilistic Approach to Multiple-Subject Diffusion MRI Tractography, Medical Image Analysis, 2011 Aug;15(4):414-25.

Whole Brain HARDI Tractography (CMRR, Aganj et al.)

This is the most robust tractography algorithm we have ever used (avoids ‘spaghetti’)

Trying it now in many clinical projects (HIV, 22q, children)

Collaborating on better mathematical models of Diffusion - critical to infer FA, fiber directions, connectivity

To capture diffusion at multiple b-values, To capture diffusion at multiple b-values, we studied a fast q-space sampling schemewe studied a fast q-space sampling scheme

(“staggered HYDI"; Zhan ISBI 2011) (“staggered HYDI"; Zhan ISBI 2011)

Sample first b-value shellUniformly on sphere

(electrostaticprinciple)

Interleave New shells with higher diffusion

weightings (b=1000,2000, 3000 s/mm2

at 7 Tesla)

Multi-shell HYDI using TDF (Zhan ISBI Multi-shell HYDI using TDF (Zhan ISBI 2011)2011)

- - compare ODFs + tractography from each shell, compare ODFs + tractography from each shell, combined, sub-sampled combined, sub-sampled

14

Thanks to the CMRR P41:Thanks to the CMRR P41:

Many UCLA projects benefit from CMRR’s scientific innovations

Support includes: scans, algorithms, unique expertise

>30 joint papers in 4 years

2 collaborative funded R01s (7T, HARDI)

another collaborative R01 is being planned today!