Multiparameter MRI Analysis of the Time Course of Induced Muscle Damage and Regeneration

作者：Feng Shu; Chen Daniel; Kushmerick Martin; Lee Donghoon^*

来源：Journal of Magnetic Resonance Imaging, 2014, 40(4): 779-788.

DOI：10.1002/jmri.24417

• skeletal muscle
• MRI
• necrosis
• regeneration
• myotoxin

Purpose: To test the ability of different magnetic resonance imaging (MRI) modalities to discriminate the time course of damage and regeneration in a model of acute, toxin-induced muscle damage.
Materials and Methods: We analyzed the time course of tissue and cellular changes in mouse lower limb musculature following localized injection of myotoxin by T-2, magnetization transfer (MT), and diffusion-weighted MRI. We also used T-1-weighted imaging to measure leg muscle volume. In addition, postmortem histological analysis of toxin-injected muscles was compared to uninjected controls.
Results: The damages detected by the MRI modalities are transient and recover within 3 weeks. Muscle water diffusivity and edema measured by leg volume increased within the first hours after injection of the toxin. The rate constant for volume increase was 0.65 +/- 0.11 hr(-1), larger than the increase in T-2 (0.045 +/- 0.013 hr(-1)) and change in MT ratio (0.028 +/- 0.021 hr(-1)). During repair phase, the rate constants were much smaller: 0.022 +/- 0.004 hr(-1), 0.013 +/- 0.0019 hr(-1) and 0.0042 +/- 0.0016 hr(-1) for volume, T-2, and MT ratio, respectively. Histological analyses confirmed the underlying cellular changes that matched the progression of MR images.
Conclusion: The kinetics of change in the MRI measurements during the progression of damage and repair shows MRI modalities can be used to distinguish these processes.

• 出版日期2014-10