Abstract：
Three-dimensional (3D) ultrasonic imaging can enable post-facto plane of interest selection. It can be performed with devices such as wobbler probes, matrix probes, and sensor-based probes. Ultrasound systems that support 3D-imaging are expensive with added hardware complexity compared to 2D-imaging systems. An inertial measurement unit (IMU) can potentially be used for 3D-imaging by using it to track the motion of a one-dimensional array probe and constraining its motion in one degree of freedom (1-DoF) rotation (swept-fan). This work demonstrates the feasibility of an affordable IMU-assisted manual 3D-ultrasound scanner (IAM3US). A consumer-grade IMU-assisted 3D scanner prototype is designed with two support structures for swept-fan. After proper IMU calibration, an appropriate KF-based algorithm estimates the probe orientation during the swept-fan. An improved scanline-based reconstruction method is used for volume reconstruction. The evaluation of the IAM3US system is done by imaging a tennis ball filled with water and the head region of a fetal phantom. From fetal phantom reconstructed volumes, suitable 2D planes are extracted for biparietal diameter (BPD) manual measurements. Later, in-vivo data is collected. The novel contributions of this paper are (1) the application of a recently proposed algorithm for orientation estimation of swept-fan for 3D imaging, chosen based on the noise characteristics of selected consumer grade IMU (2) assessment of the quality of the 1-DoF swept-fan scan with a deflection detector along with monitoring of maximum angular rate during the scan and (3) two probe holder designs to aid the operator in performing the 1-DoF rotational motion and (4) end-to-end 3D-imaging system-integration. Phantom studies and preliminary in-vivo obstetric scans performed on two patients illustrate the usability of the system for diagnosis purposes.
摘要：
三维(3D)超声成像可以实现事后的感兴趣平面选择。它可以用摆动探针等设备进行，矩阵探针,和基于传感器的探头。与2D成像系统相比,支持3D成像的超声系统是昂贵的,具有增加的硬件复杂性。惯性测量单元(IMU)可以潜在地用于3D成像,通过使用它来跟踪一维阵列探头的运动并将其运动约束在一个自由度(1-DoF)旋转(扫掠扇形)中。这项工作证明了负担得起的IMU辅助手动3D超声扫描仪（IAM3US）的可行性。设计了一种消费级IMU辅助的3D扫描仪原型，该原型具有两个用于扫掠风扇的支撑结构。经过适当的IMU校准后，适当的基于KF的算法估计扫掠扇期间的探头方向。一种改进的基于扫描线的重建方法用于体积重建。IAM3US系统的评估是通过对充满水的网球和胎儿体模的头部区域进行成像来完成的。从胎儿幻影重建的体积中，提取合适的2D平面用于双顶直径(BPD)手动测量。稍后，收集体内数据。本文的新贡献是（1）最近提出的算法用于3D成像的扫掠扇的方向估计的应用，根据选定的消费级IMU的噪声特性进行选择（2）使用偏转检测器对1-DoF扫掠扇形扫描的质量进行评估，并监测扫描过程中的最大角速度，以及（3）两个探头支架设计以帮助操作员执行1-DoF旋转运动和（4）端到端3D成像系统集成。对两名患者进行的体模研究和初步的体内产科扫描说明了该系统用于诊断目的的可用性。
