Flow imaging on breast ultrasonography in daily practice

Abstract

At the core of breast ultrasonography is the B-mode examination. B-mode ultrasound is a form of morphological diagnosis in which pathological features are interpreted through ultrasound images composed of the ultrasound signals from objects. Color Doppler ultrasound is a form of vascular imaging, overlapping the color flow mapping formed from the Doppler shift frequency on a B-mode image. Proper equipment settings and examination techniques are essential for successful breast color Doppler examinations, leading to a better ultrasound diagnosis. In contrast-enhanced ultrasonography, ultrasound images are generated from nonlinear responses from microbubbles oscillating at a lower sound pressure, so it is called contrast harmonic imaging. Estimation of histopathology and the subsequent categorization on B-mode ultrasound are at the core of breast ultrasonography. And the addition of flow imaging to B-mode makes it possible to improve the diagnosis on breast ultrasonography so that we can reliably diagnose breast cancer and benign lesions, as well as avoid unnecessary biopsies. In this review article, I will describe the principles of color Doppler ultrasonography and contrast-enhanced ultrasonography, the history of flow imaging in breast ultrasound, the histopathology of vascularity on breast lesions, equipment settings, and examination techniques for Doppler ultrasonography. In addition, I will discuss how to utilize flow imaging in breast ultrasonography in daily practice.