Effect of passive muscle length change on apparent diffusion coefficient: detection with clinical MR imaging.
OBJECTIVE
We investigated whether change in muscle microstructure associated with passive extension and contraction affects proton diffusivity.


METHODS
In 6 male subjects, we compared apparent diffusion coefficients (ADC) along the posterior-to-anterior (ADC-PA), right-to-left (ADC-RL) and superior-to-inferior (ADC-SI) directions of the right tibialis anterior muscle with the ankle joint in passive plantar flexion and passive dorsiflexion.


RESULTS
Compared to the respective ADCs at plantar flexion, the ADC-PA (P=0.002) and ADC-RL (P=0.008) were significantly greater, but ADC-SI (P=0.008) significantly lower at dorsiflexion.


CONCLUSIONS
Our results indicate that change in muscle microstructure associated with passive extension and contraction would affect proton diffusivity, and this alteration of proton diffusivity could be detected by measuring ADC with a clinical magnetic resonance scanner.
Hatakenaka
Masamitsu
M
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Radiology Center, Kyushu University Hospital, Fukuoka, Japan. mhatake@radiol.med.kyushu-u.ac.jp
Yabuuchi
Hidetake
H
Matsuo
Yoshio
Y
Okafuji
Takashi
T
Kamitani
Takeshi
T
Setoguchi
Taro
T
Nishikawa
Kei
K
Honda
Hiroshi
H
D000328:Adult; D001834:Body Water / Q000737:chemistry* / Q000502:physiology*; D004058:Diffusion; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000737:chemistry* / Q000502:physiology*