Laboratorio de Acústica Ultrasonora, Facultad de Ciencias, Igua 4225, 11400, Montevideo, Uruguay.
Phys Med Biol. 2010 Mar 21;55(6):1753-65. doi: 10.1088/0031-9155/55/6/014. Epub 2010 Mar 2.
In this paper 1D transient elastography was employed in fresh bovine skeletal muscle samples to assess the shear elastic modulus mu while the tissue was locally heated by means of an electrical resistance. The investigation is based on the study of the time shift of the shear wave propagation produced by the local temperature variation. The experiments show that the thermal expansion contribution to the time shift is negligible when compared with the shear wave speed variation. In such a case, the quantification of mu as a function of temperature becomes possible. Repeated experiments in different samples lead to a reproducible behavior of mu as a function of temperature. Irreversible elasticity changes are produced when the temperature exceeds a certain critical value T(c). The proposed method allows estimating this value as well as the spatial extension of the resulting thermal lesion. This point is important when considering applications in monitoring focused ultrasound surgery (FUS) because the surrounding normal tissue should remain unaffected.
本文采用一维瞬态弹性成像技术，对新鲜牛骨骼肌样本进行剪切弹性模量 μ 的评估，同时利用电阻对组织进行局部加热。该研究基于局部温度变化产生的剪切波传播时间位移的研究。实验表明，与剪切波速度变化相比，热膨胀对时间位移的贡献可以忽略不计。在这种情况下，可以实现 μ 随温度的定量变化。在不同样本中的重复实验导致 μ 随温度的重现性行为。当温度超过某个临界值 T(c)时，会产生不可逆的弹性变化。该方法允许估计这个值以及由此产生的热损伤的空间扩展。当考虑在监测聚焦超声手术（FUS）中的应用时，这一点很重要，因为周围的正常组织应该不受影响。
