UCL Centre for Medical Image Computing
Camino and DTI-TK: DTI TK: Advanced Diffusion MRI Pipeline for Traumatic Brain Injury Gary Hui Zhang, PhD Micr...
Camino and DTI-TK: DTI TK: Advanced Diffusion MRI Pipeline for Traumatic Brain Injury Gary Hui Zhang, PhD Microstructure Imaging Group Centre for Medical Image Computing Department of Computer Science University College London
26th of June, 2013
Mi Microstructure t t iimaging i with ith diffusion diff i MRI
Diffusion MRI D
Signal
Predict P
Estimate E
Diffusion MRI quantify water mobility in tissue
Histology y
Tissue Cell size, shape, density Membrane permeability Orientation distribution Axer, J. Neuro. Meth. 1999
Virtual Vi t l Histology Tissue Modeling Model parameters are the tissue microstructure feature themselves!
Pi li ffor advanced Pipeline d d diff diffusion i MRI analysis l i
Imaging g g
Inference
Localization
Normalization
Pi li ffor advanced Pipeline d d diff diffusion i MRI analysis l i
Imaging g g
Inference
Localization
Normalization
Camino: a platform for advanced diffusion MRI analysis l i • Implements a rich hierarchy of analytic models for diffusion MRI • Provides a robust framework for fitting diffusion MRI data to the models • Delivers a sophisticated simulator for validating diffusion MRI models
Monte Carlo Diffusion Simulator ((Hall and Alexander,, IEEE TMI 2009) Displacement PDF
Diffusion MR Signal
Availab ble Substtrates
Simu ulation Pipeline
Diffusion Substrate
Gamma-Distributed Radii
Crossing Cylinders
Permeable Cylinders
Mesh-based substrates
Rich hierarchyy of analytic y models of diffusion MRI (Panagiotaki et al, NeuroImage 2012)
Compartment Models Stick
Cylinder
GDRCylinders
Ball
Zeppelin
Tensor
Multi-Compartment Models
Astrosticks
Astrocylinders
Sphere
Dot
ZeppelinStickAstrosticks
Mapping axon diameter and density in the living h human b brain i with ith A ActiveAx ti A (Alexander et al, NeuroImage 2010)
Fixed tissue: • Vervet monkey • 4.7T; 140mT/m
In vivo: • human volunteer • 3T; 60mT/m
Mapping neurite orientation dispersion and d density it with ith NODDI (Zhang et al, NeuroImage 2012) NODDI
DTI Dominant Orientation
Orientation Dispersion
Fractional Anisotropy 0
1
0
Neurite Density 1
0
CSF 1
0
The acquisition protocol is simple to implement and clinically feasible.
1
Neurite density: a potential imaging marker for b i recovery (Wang et al, PLoS One 2013) brain
NODDI enables the extension of this animal model study to living human subjects.
Pi li ffor advanced Pipeline d d diff diffusion i MRI analysis l i
Imaging g g
Inference
Localization
Normalization
Diffusion MRI supports superior anatomical li t off white hit matter tt structures t t alignment DTI
T1
? Corpus Callosum O ti Radiation Optic R di ti Arcuate Fasciculus
DTI-TK provides the state-of-the-art for aligning diff i MRI d diffusion data t • Ranked the best performing tool of its kind (Wang et al, NeuroImage 2011) • Supports unbiased longitudinal analysis of diffusion MRI data (Keihaninejad et al, al NeuroImage 2013)
The importance of tensor-based alignment for l longitudinal it di l processing i (Keihaninejad et al, NeuroImage 2013)
Tensor-based alignment improves specificity
The importance of tensor-based alignment for l longitudinal it di l processing i (Keihaninejad et al, NeuroImage 2013)
Tensor-based alignment improves sensitivity
Pi li ffor advanced Pipeline d d diff diffusion i MRI analysis l i
Imaging g g
Inference
Localization
Normalization
Tract-specific p analysis y with DTI-TK ((Yushkevich et al,, NeuroImage 2008; Zhang et al, Medical Image Analysis 2010)
• Evaluate specific a priori hypotheses (e.g., ALS impairs only motor tracts) • Reduce confounding effect of neighboring structures • Present findings in the context natural to the structure
Typical Voxelwise Analysis
Tract-Specific Analysis
Summary • Camino provides a rigorous platform for • developing and validating advanced diffusion MRI methods • applying these methods to routine clinical research and practice • DTI-TK supports population-based analysis of diffusion MRI data by • implementing the state-of-the-art spatial normalization tool • delivering a statistical inference tool tailored specifically for white matter • T Together, th they th deliver d li an end-to-end dt d pipeline i li ffor advanced d d diff diffusion i MRI analysis
A k Acknowledgement l d t • Colleagues at • CMIC and MIG (UCL) • Penn Image Computing and Science Laboratory (U Penn)
• Camino funding support • EU CONNECT consortium (www.brain-connect.eu) • MS Society of Great Britain and Northern Ireland • UCLH Biomedical Research Centre funded by NIHR
• DTI-TK funding support • NIH-NIBIB R03-EB009321 • NIH-NINDS R01-NS065347