Department of Biomedical Engineering, School of Life Science and Technology, Key Laboratory of Molecular Biophysics of Education Ministry of China, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Tongji Hospital affiliated to Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei, China.
Ultrasonics. 2024 Mar;138:107212. doi: 10.1016/j.ultras.2023.107212. Epub 2023 Nov 30.
Breast ultrasound computed tomography (USCT) has been gradually promoted to clinical application after years of rapid development. Compared with the traditional handheld ultrasound scanning method, the scanning plane of USCT is fixed at the coronal plane, and the scanning path is designed in advance; the acoustic window is not in direct contact with the breast, a lot of coupling medium (usually degassed water is used to fill the gaps between the probe and breast. The clinical application of breast USTC faces challenges: (1) the processes of water degassing, heating, filling, draining, and cleaning prolong the entire scan cycle and reduce patient throughput. (2) The breast is not stabilized and slight movements of the breast may cause motion artifacts in the USCT images. (3) The non-normal incidence of ultrasound into the breast causes reflected and transmitted signals received with a low signal-to-noise ratio (SNR) or even unable to be detected. This article proposes a coupling, stabilizing, and shaping strategy for the clinical application of USCT with a ring array transducer. The solid gel coupling agent (SGCA) is applied for coupling, and a set of SGCA moldings is designed to stabilize and shape the breast during scanning, the breast shape and size which vary from person to person are simplified into several models. The preparation time is reduced to less than 1 min by replacing disposable moldings. The results show that the breast after shaping is close to round in the coronal plane, and slopes of the breast skin are limited in the sagittal and transverse planes, the breast subcutaneous tissue (fat and glands) has a better contrast-to-noise ratio (CNR) and can be better distinguished in the reflection images than that of the breast without shaping. The mean value of the raw beamformed data which represents the reflection signal amplitude of breast subcutaneous tissue after shaping shows 1.5 times that of the breast without shaping, the signal-to-noise ratio (SNR) of the raw transmission signal data after breast shaping is overall higher than that of the breast without shaping. The application of SGCA moldings for breast coupling, stabilizing, and shaping also benefits establishing a standardized scanning process, the standardized diagnosis of the breast lesion, and the localization of breast lesions.
乳腺超声计算机断层扫描（USCT）经过多年的快速发展，逐渐推广到临床应用。与传统的手持式超声扫描方法相比，USCT 的扫描平面固定在冠状面，扫描路径预先设计；声窗不与乳房直接接触，使用大量的耦合剂（通常是脱气水）填充探头和乳房之间的间隙。乳腺 USCT 的临床应用面临挑战：（1）水脱气、加热、填充、排水和清洗过程延长了整个扫描周期，降低了患者的吞吐量。（2）乳房不稳定，乳房的轻微运动可能导致 USCT 图像中的运动伪影。（3）超声非正入射进入乳房会导致接收到的反射和透射信号信噪比（SNR）较低，甚至无法检测到。本文提出了一种基于环形阵列换能器的 USCT 临床应用的耦合、稳定和成型策略。使用固体凝胶耦合剂（SGCA）进行耦合，并设计了一套 SGCA 成型模具，在扫描过程中稳定和成型乳房，将因人而异的乳房形状和大小简化为几种模型。通过更换一次性模具，将准备时间减少到 1 分钟以内。结果表明，成型后的乳房在冠状面接近圆形，乳房皮肤的斜率在矢状面和横断面上受到限制，乳房皮下组织（脂肪和腺体）具有更好的对比噪声比（CNR），并且在反射图像中比未成型的乳房更好地分辨。代表乳房皮下组织反射信号幅度的原始波束形成数据的平均值显示，成型后比未成型时提高了 1.5 倍，乳房成型后的原始透射信号数据的信噪比（SNR）整体高于未成型时的 SNR。SGCA 成型模具在乳房耦合、稳定和成型中的应用也有利于建立标准化的扫描流程、标准化的乳腺病变诊断和乳腺病变的定位。
