IEEE Trans Ultrason Ferroelectr Freq Control. 2021 Jan;68(1):65-71. doi: 10.1109/TUFFC.2020.3009135. Epub 2020 Dec 23.
To understand the in-plane elastic character of ultrasonic waves in the skull, longitudinal wave velocities were studied in the MHz range using a conventional pulse technique. Taking advantage of the thickness of swine skulls, anisotropic in-plane wave velocity changes in the outer and diploe layers were experimentally investigated using structural information measured by X-ray computer tomography (CT). The velocities in the thin inner layer were difficult to measure. The main trabecular alignment (MTA) in the thick swine diploe layer was almost perpendicular to the thickness direction and changed with position inside the skull. The degree of anisotropy of in-plane longitudinal wave velocity ranged 1.07-1.33 in both outer and diploe layers, depending on position and swine sample. The angle of the fastest velocity in the outer layer was different from that in most parts of the diploe layer. Anisotropic character in the diploe layer gradually changed with position in the thickness direction.
为了了解颅骨中超声波的面内弹性特性，使用常规脉冲技术在 MHz 范围内研究了纵波速度。利用猪颅骨的厚度，通过 X 射线计算机断层扫描（CT）测量的结构信息，实验研究了外板和板障层中各向异性的面内波速度变化。由于内层很薄，因此难以测量速度。在厚的猪板障层中，主要的骨小梁排列（MTA）几乎垂直于厚度方向，并随颅骨内部的位置而变化。在内外板中，面内纵波速度的各向异性度范围为 1.07-1.33，具体取决于位置和猪样本。外层中最快速度的角度与板障层的大部分区域不同。板障层中的各向异性特征随厚度方向的位置逐渐变化。
