MR elastography in a murine stroke model reveals correlation of macroscopic viscoelastic properties of the brain with neuronal density

作者：Freimann Florian Baptist; Mueller Susanne; Streitberger Kaspar Josche; Guo Jing; Rot Sergej; Ghori Adnan; Vajkoczy Peter; Reiter Rolf; Sack Ingolf; Braun Juergen^*

来源：NMR in Biomedicine, 2013, 26(11): 1534-1539.

DOI：10.1002/nbm.2987

• MR elastography
• mouse brain
• stroke
• ischemia
• middle cerebral artery occlusion
• neuronal density
• viscoelastic network

The aim of this study was to investigate the influence of neuronal density on viscoelastic parameters of living brain tissue after ischemic infarction in the mouse using MR elastography (MRE). Transient middle cerebral artery occlusion (MCAO) in the left hemisphere was induced in 20 mice. In vivo 7-T MRE at a vibration frequency of 900 Hz was performed on days 3, 7, 14 and 28 (n=5 per group) after MCAO, followed by the analysis of histological markers, such as neuron counts (NeuN). MCAO led to a significant reduction in the storage modulus in the left hemisphere relative to contralateral values (p=0.03) without changes over time. A correlation between storage modulus and NeuN in both hemispheres was observed, with correlation coefficients of R=0.648 (p=0.002, left) and R=0.622 (p=0.003, right). The loss modulus was less sensitive to MCAO, but correlated with NeuN in the left hemisphere (R=0.764, p=0.0001). In agreement with the literature, these results suggest that the shear modulus in the brain is reduced after transient ischemic insult. Furthermore, our study provides evidence that the in vivo shear modulus of brain tissue correlates with neuronal density. In diagnostic applications, MRE may thus have diagnostic potential as a tool for image-based quantification of neurodegenerative processes.

• 出版日期2013-11
• 单位河北医科大学