Multiscale structural analysis of mouse lingual myoarchitecture employing diffusion spectrum magnetic resonance imaging and multiphoton microscopy

Abstract

The tongue consists of a complex, multiscale array of myofibers that comprise the anatomical underpinning of lingual mechanical function. 3-D myoarchitecture was imaged in mouse tongues with diffusion spectrum magnetic resonance imaging DSI at 9.4 T bmax 7000 s /mm, 150- m isotropic voxels , a method that derives the preferential diffusion of water/voxel, and high-throughput 10 fps two-photon microscope TPM . Net fiber alignment was represented for each method in terms of the local maxima of an orientational distribution function ODF derived from the local diffusion DSI and 3-D structural autocorrelation TPM , respectively. Mesoscale myofiber tracts were generated by alignment of the principal orientation vectors of the ODFs. These data revealed a consistent relationship between the properties of the respective ODFs and the virtual superimposition of the distributed mesoscale myofiber tracts. The identification of a mesoscale anatomical construct, which specifically links the microscopic and macroscopic spatial scales, provides a method for relating the orientation and distribution of cells and subcellular components with overall tissue morphology, thus contributing to the development of multiscale methods for mechanical analysis.