Measuring Microstructural Features Related to Neuronal Activation Using Diffusion MRI and Three-Compartment Diffusion Models: A Feasibility Study

Irina Kezele¹, Daniel C. Alexander², Philip Batchelor³, Jean-Franois Mangin¹, Denis Le Bihan¹, Cyril Poupon¹

We propose an analytic three-compartment diffusion model to explain the diffusion signal coming from tissues that are assumed to comprehend the intracellular and extracellular free water pools and a membrane-bound water pool, as hypothesized in a recent paper by Le Bihan (Phys. Med. Biol. 2007). Using this model we deliver an optimized imaging protocol to measure the relevant model parameters. Simulation experiments demonstrate the accuracy of estimating all the model parameters. In particular, the accurate estimation of membrane-water compartment size promotes the potential to detect the changes of this size that has been suggested to be related to neuronal activation.