IEEE Trans Ultrason Ferroelectr Freq Control. 2021 Jan;68(1):116-126. doi: 10.1109/TUFFC.2020.2993810. Epub 2020 Dec 23.
Phase-controlled focused ultrasound transducers have opened up a new way to noninvasively treat brain diseases. However, due to the geometry and the heterogeneous medium of the human skull, the currently used hemispherical transducers cannot guarantee that the ultrasound emitted by the transducer penetrates the skull normally; consequently, the impact of the shear wave on the treatment area has to be considered. The usual approach is to turn off elements in the transducer with excessively large incident angles, but this approach reduces the efficiency of the transducer. This article presents the design of a novel transducer that can be rotated according to the different geometric shapes of the skull. The incident angles of the elements in the transducer are modified so that the effect of the shear wave on the treatment area can be ignored and the efficiency of the transducer is improved. The results of computed tomography (CT) model simulation of nine skulls verify the versatility and feasibility of the new transducer. We believe that this kind of rotatable transducer has clinical and engineering significance.
相控聚焦超声换能器为非侵入式治疗脑部疾病开辟了新途径。然而，由于人体颅骨的几何形状和不均匀介质，目前使用的半球形换能器不能保证换能器发出的超声波正常穿透颅骨；因此，必须考虑剪切波对治疗区域的影响。通常的方法是关闭具有过大入射角的换能器元件，但这种方法会降低换能器的效率。本文提出了一种新型换能器的设计，该换能器可以根据颅骨的不同几何形状进行旋转。对换能器中元件的入射角进行修正，从而可以忽略剪切波对治疗区域的影响，提高换能器的效率。九例颅骨的计算机断层扫描（CT）模型模拟结果验证了新型换能器的通用性和可行性。我们相信这种可旋转的换能器具有临床和工程意义。
