Whole-brain diffusional variance decomposition (DIVIDE): Demonstration of technical feasibility at clinical MRI systems

TL;DR

This study demonstrates that whole-brain diffusional variance decomposition (DIVIDE) using q-space trajectory encoding (QTE) is technically feasible across various clinical MRI systems, enabling advanced tissue microstructure analysis beyond conventional methods.

Contribution

The paper introduces a validated protocol for implementing DIVIDE with QTE on diverse MRI systems, expanding its potential clinical applicability.

Findings

Feasibility demonstrated at all tested MRI systems.

High-performance systems achieved 2 mm isotropic resolution.

Lower-performance systems obtained acceptable images at 2.5x2.5x4 mm3 resolution.

Abstract

Purpose: To assess the technical feasibility of whole-brain diffusional variance decomposition (DIVIDE) based on q-space trajectory encoding (QTE) at clinical MRI systems with varying performance. DIVIDE is used to separate diffusional heterogeneity into components that arise due to isotropic and anisotropic tissue structures. Methods: We designed imaging protocols for DIVIDE using numerically optimized gradient waveforms for diffusion encoding. Imaging was performed at systems with magnetic field strengths between 1.5 and 7 T, and gradient amplitudes between 33 and 80 mT/m. Technical feasibility was assessed from signal characteristics and quality of parameter maps in a single volunteer scanned at all systems. Results: The technical feasibility of QTE and DIVIDE was demonstrated at all systems. The system with the highest performance allowed whole-brain DIVIDE at 2 mm isotropic voxels. The system with the lowest performance required a spatial resolution of 2.5x2.5x4 mm3 to yield a sufficient signal-to-noise ratio. Conclusions: Whole-brain DIVIDE based on QTE is feasible at the investigated MRI systems. This demonstration indicates that tissue features beyond those accessible by conventional diffusion encoding may be explored on a wide range of MRI systems.