Fanctional Imaging of Muscle Contraction caused by Electric Stimulation
Watanabe Y, Umeda M, Higuchi M, Kimura K, Aoki I, Tanaka C, Naruse S
Meiji School of Oriental Medicine
The purpose of this study is to visualize muscle contraction during electric stimulation using dynamic DWI. Seven healthy volunteers underwent MRI of the lower extremities with single shot diffusion EPIs and phase contrast gradient echo, respectively. In the results, the DWI signal intensity in the stimulated muscles was decreased by the electric stimulation. The speed of muscle shortening was estimated from the phase contrast images. However, muscle deformation was not enough to explain the signal decrease in DWI. We suggest that the signal reduction in DWI is caused by incoherent water movement in the tissue, caused by the intramuscular structure.