A magnetic resonance imaging-compatible, large-scale array for trans-skull ultrasound surgery and therapy
A magnetic resonance imaging-compatible, large-scale array for trans-skull ultrasound surgery and therapy
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DOI：
10.7863/jum.2005.24.8.1117
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发表时间：
2005-08-01
影响因子：
2.3
通讯作者：
Hynynen, K
中科院分区：
文献类型：
--
作者：
Clement, GT;White, PJ;Hynynen, K
Objective.超声换能器阵列和放大器技术的进步促使了许多有趣的超声治疗科学建议。这些包括轻度侵入性和非侵入性技术，用于通过颅骨的超声脑外科手术。在以前的工作中，它被证明是如何一个500元半球形换能器可以纠正由颅骨与换能器，工作在0.8 MHz附近的频率引起的波失真。由于目标为trans-skull聚焦是其在临床上的最终用途，一个新的半球相控阵系统，现在已经开发出的声学参数进行了优化，以匹配在初步研究中确定的值。方法.换能器进行了测试，通过聚焦超声波通过体外人类头骨，并通过相位自适应聚焦技术进入大脑模型。同时，通过使用磁共振引导和温度测量来监测该过程。结果一个500个元件的30厘米直径，0.81 MHz的阵列的超声焦点可以通过电子控制的体积约为30 × 30 × 26毫米的头骨。此外，温度监测的内表面和外表面的头骨显示，该阵列可以凝固目标脑组织，而不会导致过度的头骨加热。结论.这些实验的成功结果表明，可以产生足够高的强度来破坏脑组织，而不会过度加热周围区域，也不会产生大的磁共振噪声和伪影。
Objective. Advances in ultrasound transducer array and amplifier technologies have prompted many intriguing scientific proposals for ultrasound therapy. These include both mildly invasive and noninvasive techniques to be used in ultrasound brain surgery through the skull. In previous work, it was shown how a 500-element hemisphere-shaped transducer could correct the wave distortion caused by the skull with a transducer that operates at a frequency near 0.8 MHz. Because the objective for trans-skull focusing is its ultimate use in a clinical context, a new hemispheric phased-array system has now been developed with acoustic parameters that are optimized to match the values determined in preliminary studies. Methods. The transducer was tested by focusing ultrasound through ex vivo human skulls and into a brain phantom by means of a phase-adaptive focusing technique. Simultaneously, the procedure was monitored by the use of magnetic resonance guidance and thermometry. Results. The ultrasound focus of a 500-element 30-cm-diameter, 0.81-MHz array could be steered electronically through the skull over a volume of approximately 30 x 30 x 26 mm. Furthermore, temperature monitoring of the inner and outer surfaces of the skull showed that the array could coagulate targeted brain tissue without causing excessive skull heating. Conclusions. The successful outcome of these experiments indicates that intensities high enough to destroy brain tissue can be produced without excessive heating of the surrounding areas and without producing large magnetic resonance noise and artifacts.