# Tensor-valued diffusion MRI in under 3 minutes: An initial survey of microscopic anisotropy and tissue heterogeneity in intracranial tumors

## TL;DR

This study demonstrates that a rapid 3-minute diffusion MRI protocol can reliably assess microscopic tissue properties in intracranial tumors, enabling faster clinical evaluations.

## Contribution

It introduces a fast b-tensor encoding protocol that accurately measures tissue heterogeneity and anisotropy in intracranial tumors within a clinically feasible time.

## Key findings

- Fast protocol yields similar parameters to full protocol.
- Glioblastomas show lower anisotropy than meningiomas.
- Metastases exhibit higher tissue heterogeneity than other tumor types.

## Abstract

Purpose: To evaluate the feasibility of a 3-minute b-tensor encoding protocol for diffusion MRI-based assessment of the microscopic anisotropy and tissue heterogeneity in a wide range of intracranial tumors. Methods: B-tensor encoding was performed in 42 patients with intracranial tumors (gliomas, meningiomas, adenomas, metastases). Microscopic anisotropy and tissue heterogeneity were evaluated by estimating the anisotropic kurtosis ($MK_A$) and isotropic kurtosis ($MK_I$), respectively. An extensive imaging protocol was compared with a faster 3-minute protocol. Results: The fast imaging protocol yielded parameters with characteristics in terms of bias and precision similar to the full protocol. Glioblastomas had lower microscopic anisotropy than meningiomas $(MK_A = 0.29 \pm 0.06$ versus $0.45\pm0.08, p = 0.003)$. Metastases had higher tissue heterogeneity $(MK_I = 0.57\pm0.07)$ than both the glioblastomas $(0.44\pm0.06, p < 0.001)$ and meningiomas $(0.46\pm0.06, p = 0.03)$. Conclusion: Evaluation of the microscopic anisotropy and tissue heterogeneity in intracranial tumor patients is feasible in clinically relevant times frames.

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Source: https://tomesphere.com/paper/1902.09986