Double diffusion encoding and applications for biomedical imaging

Diffusion Magnetic Resonance Imaging (dMRI) is one of the most important contemporary non-invasive modalities for probing tissue structure at microscopic scale. The majority dMRI techniques employ standard single diffusion encoding (SDE) measurements, covering different sequence parameter ranges depending on complexity method. Although many signal representations and biophysical models have been proposed SDE data, they are intrinsically limited by a lack specificity. Advanced methods to provide additional microstructural information beyond what can be inferred from SDE. These enhanced contrasts play roles in characterizing biological tissues, instance upon diseases (e.g. neurodegenerative, cancer, stroke), aging, learning, development. In this review we focus double (DDE), which stands out among other advanced acquisitions its versatility, ability probe more specific correlations, feasibility preclinical clinical applications. Various DDE methodologies employed compartment sizes (Section 3), decouple effects anisotropy orientation dispersion 4), displacement study exchange, or suppress fast diffusing compartments 6). measurements also used improve robustness 5) intra-cellular via magnetic resonance spectroscopy metabolites 7). This discusses all these topics as well practical aspects related implementation contrast settings 9) aims readers guide deciding right acquisition their application.