Sports Okinawa, 4-19-7 Jitchaku, Urasoe-shi, Okinawa 901-2122, Japan. Department of Sports Research, Japan Institute of Sports Sciences, 3-15-1 Nishigaoka, Kita-ku, Tokyo 115-0056, Japan. Author to whom any correspondence should be addressed.
Physiol Meas. 2018 Nov 6;39(11):115003. doi: 10.1088/1361-6579/aae7e2.
To examine the influence of pennation angle on measurement of shear wave elastography, this study utilised the propagation view mode that can reveal shear wave propagation in human pennate muscle in vivo.
The validity of the propagation view mode was qualitatively confirmed by observation of shear wave propagation in tissue-mimicking phantoms. Shear wave velocity of the medial gastrocnemius (MG) was evaluated in 15 healthy males. By changing the placement of the ultrasound probe on the skin surface, shear wave propagation in the MG was changed: shear waves propagated along the MG fascicles (horizontal condition) and across the fascicles (oblique condition).
It was observed that shear wave propagation became faster when shear waves passed through stiffer parts of the phantoms and perimysium of the MG, which is concordant with the basic principle of shear wave elastography. Shear wave velocity in the horizontal condition (2.69 ± 0.71 m s) was significantly higher than that in the oblique condition (2.61 ± 0.73 m s) (p < 0.001), but the effect size was small (Cohen's d = 0.11).
Ultrasound shear wave elastography can evaluate tissue elasticity of pennate muscles along the fascicle direction, even if shear waves propagate across the obliquely arranged fascicles.
探讨羽状角对剪切波弹性成像测量的影响，本研究采用能在活体人羽状肌中显示剪切波传播的传播视图模式。
通过观察组织模拟体中的剪切波传播，定性确认传播视图模式的有效性。评估了 15 名健康男性的内侧腓肠肌（MG）的剪切波速度。通过改变皮肤表面上超声探头的放置位置，改变 MG 中的剪切波传播：剪切波沿 MG 束传播（水平条件）和穿过束（斜向条件）。
观察到当剪切波穿过更硬的组织和 MG 的肌周膜时，剪切波传播速度变快，这与剪切波弹性成像的基本原理一致。水平条件下的剪切波速度（2.69 ± 0.71 m/s）明显高于斜向条件下的剪切波速度（2.61 ± 0.73 m/s）（p < 0.001），但效应量较小（Cohen's d = 0.11）。
超声剪切波弹性成像可以评估羽状肌沿束方向的组织弹性，即使剪切波斜向传播穿过束。
