In vivo breast tumor detection using transient elastography

Abstract

This paper presents first in vivo experiments for breast tumor detection using transient elastography. This technique has been developed for detection and quantitative mapping of hard lesions in soft tissues. It consists in following the propagation inside soft tissues of very low-frequency shear waves (approximately 60 Hz) generated by a vibrating system located at the body surface. Because transient shear waves propagate through the medium in less than 0.1 s, the shear propagation imaging is performed with an ultrafast echographic scanner able to reach frame rates up to 6000 Hz. The local shear wave speed is directly linked to the local shear Young's modulus of the medium. The shear elasticity map of the medium can then be computed using an inversion algorithm. In vivo experiments were conducted on 15 women who had palpable breast lesions. For clinical adaptability reasons, shear waves were generated by the surface of the ultrasound (US) imaging transducer itself, which was linked to a mechanical vibrator. Our preliminary in vivo results demonstrate the clinical applicability of the transient elastography technique for breast lesion detection.