Measurement of the Orientation of 2D Ultrasound Probe for Medical Diagnosis of Left Ventricular Motion

摘要

This paper describes a method to measure the orientation of 2D ultrasound probe during medical examination of left ventricle (LV). A commercial 6-axis sensor, consisting of a 3-axis accelerometer and a 3-axis gyro sensor, was used in the measurement. The orientation of the echocardiogram was estimated by numerical integration of angular velocity which is obtained from the gyro sensors. Then, the accumulative error is reduced by the orientation correction using the direction of gravitational acceleration obtained by the accelerometer. To further improve accuracy, calibration of the echo probe direction against a datum plane was done before and after the measurement. With this method, the orientation of 2D echo probe was measured with the examinations of two healthy subjects. The estimated orientation of 2D section planes of the heart showed quite a difference from the ASE (American Society of Echocardiogram) guideline. This study reconstructed 3D image of LV motion with 8 different cross-sectional images by synchronizing the heartbeat of each data. The 3D image of the heart clearly demonstrates LV motion; however, the model suggests that the information is insufficient even with 8 echo data following the guideline of ASE.