Aubry J F, Tanter M, Pernot M, Thomas J L, Fink M
Laboratoire Ondes et Acoustique, ESPCI, Université Paris VII, U.M.R. C.N.R.S. 7587, 10 rue Vauquelin, 75005 Paris, France.
J Acoust Soc Am. 2003 Jan;113(1):84-93. doi: 10.1121/1.1529663.
Developing minimally invasive brain surgery by high-intensity focused ultrasound beams is of great interest in cancer therapy. However, the skull induces strong aberrations both in phase and amplitude, resulting in a severe degradation of the beam shape. Thus, an efficient brain tumor therapy would require an adaptive focusing, taking into account the effects of the skull. In this paper, we will show that the acoustic properties of the skull can be deduced from high resolution CT scans and used to achieve a noninvasive adaptive focusing. Simulations have been performed with a full 3-D finite differences code, taking into account all the heterogeneities inside the skull. The set of signals to be emitted in order to focus through the skull can thus be computed. The complete adaptive focusing procedure based on prior CT scans has been experimentally validated. This could have promising applications in brain tumor hyperthermia but also in transcranial ultrasonic imaging.
利用高强度聚焦超声束开展微创脑外科手术在癌症治疗中备受关注。然而，颅骨会在相位和幅度上引发强烈像差，导致波束形状严重退化。因此，要实现有效的脑肿瘤治疗，就需要考虑颅骨的影响进行自适应聚焦。在本文中，我们将证明可从高分辨率CT扫描中推断出颅骨的声学特性，并将其用于实现非侵入性自适应聚焦。我们使用了一个完整的三维有限差分代码进行模拟，考虑了颅骨内部的所有不均匀性。这样就可以计算出为透过颅骨进行聚焦而要发射的信号集。基于先前CT扫描的完整自适应聚焦程序已通过实验验证。这在脑肿瘤热疗以及经颅超声成像中可能会有很有前景的应用。
