Dr Noel Naughton - Using lattice Boltzmann simulations to analyse dMRI physics in skeletal muscle

Historically, numerical simulation of diffusion MRI has utilised either Monte Carlo or finite element methods, with Monte Carlo being the most dominant. The relevant spatial scale of these approaches can be broadly classified as either microscopic (Monte Carlo), where individual particles are tracked, or macroscopic (finite elements), which solve the continuum-level Bloch-Torrey equation. In this talk I will introduce the recently developed lattice Boltzmann method (LBM), which can be considered a mesoscopic approach, and is used to solve the Bloch-Torrey equation in a multi-compartment domain with permeable membranes. LBM considers the evolution of the Boltzmann distribution on a discreet lattice and has been successfully used in fluid dynamics to solve for a range of fluid flows. LBM is fast, scalable, and capable of handling irregular, permeable boundaries, making it well suited for simulating dMRI in biological tissue. I will discuss how LBM simulations of skeletal muscle dMRI provide insight into how microstructural changes affect the measured dMRI signal and can guide development of new ways of modeling dMRI in muscle, in particular by taking advantage of multiple diffusion times to characterise the tissue.

Noel is a postdoctoral researcher at the University of Illinois at Urbana-Champaign where he is working on the CyberOctopus project, which is developing a computational analog to living octopuses that can learn and adapt to novel tasks and environments. Prior to this he received his PhD in Mechanical Engineering from the University of Illinois where he was an NSF Graduate Research Fellow. His research is focused on developing new methods to estimate microstructural properties of skeletal muscle using dMRI and relating these properties to the muscle's mechanical functional ability.