Ultrasound diagnosis is a non-invasive examination method and diagnostic technique that uses ultrasound diagnostic instruments to examine the human body and diagnose diseases based on certain physical characteristics of ultrasound. Its advantages include non-invasive, painless, no ionizing radiation and radioactive damage, etc., high safety, convenience, real-time dynamic imaging, relatively low price, high repeatability, wide range of applications, intraoperative bedside examination, and generally no need for contrast agents. At the same time, there are some shortcomings, including poor display of bones, lungs and gastrointestinal tract, obesity, in addition to displaying the anatomical range limitations, as well as by the machine equipment, operator dependence is relatively strong, will produce a lot of ultrasound artifacts, including acoustic shadow, posterior echo enhancement, reverberation, mirror artifacts, partial volume effect, etc.. The application of ultrasound examination is relatively wide, from head to toe omnipotent and omnipresent, but some parts are not sensitive to ultrasound examination.