Color ultrasound is the application of probe examination using ultrasound Doppler technology and the principle of ultrasound echo to clearly display the various structures of the examined area on the screen in order to assist in the determination of diseases. Color ultrasound examination is a diagnostic ultrasound technology that uses the Doppler principle to superimpose a two-dimensional ultrasound image on the acquired blood flow information processed in color and brightness. Color ultrasound examination is a kind of acoustic wave conduction, which is very safe, has no radiation and is not harmful to the human body. Its application is more extensive, and it can be used for the examination of obstetrics, heart, urinary system, abdominal organs, cranium and brain and many other items. Due to the different indications, the specific examination process is not exactly the same, and the preparation before the examination is also different. Generally the ultrasound examination of abdominal organs, such as liver, gallbladder, spleen, pancreas, stomach, etc. need fasting, while other examinations such as heart, blood vessels, thyroid, breast, etc. do not need fasting preparation, but the lower abdomen and pelvic parts, such as bladder, gynecological examination, prostate examination, etc., need to hold urine. Patients who need to undergo ultrasound examination should be fully prepared before the examination under the guidance of the doctor.