Collaborations with the
UCLA Laboratory of Neuro 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 Collaborative
R01s – only possible because of the P41 –
expertise, 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.
nd
2
R01 (UCLA/CMRR) –
Compare 7T and 3T Diffusion Imaging
in 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 H
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 scanned
at both 7 and 3T
Data reconstructed
with sum-of-squares,
adaptive recombine,
SENSE1, etc.
Structural Network Hubs
Damaged by HIV
Hough Transform Tractography Algorithm
Aganj 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,
we studied a fast q-space sampling scheme
(“staggered HYDI"; Zhan ISBI 2011)
Sample first b-value shell
Uniformly on sphere
(electrostatic
principle)
Interleave
New shells with
higher diffusion
weightings (b=1000,
2000, 3000 s/mm2
at 7 Tesla)
Multi-shell HYDI using TDF (Zhan ISBI 2011)
- compare ODFs + tractography from each shell, combined, subsampled
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!