Ultrasound has been used in the clinic for more than half a century, from the initial A-type ultrasound to today’s B-type and M-type ultrasound, from two-dimensional to three-dimensional, from color Doppler ultrasound to acoustic imaging, from intracavitary ultrasound to intraoperative and interventional ultrasound, acoustic imaging technology is becoming more and more perfect and mature, providing the basis for clinical diagnosis and treatment. The following explains several common misconceptions: Misconception 1: Color ultrasound is color ultrasound. Wrong, color ultrasound is a high-definition two-dimensional (black and white) ultrasound plus color Doppler, which is an acoustic examination technique capable of determining the speed and direction of blood flow in the vascular cavity or heart cavity. Myth 2: Ultrasound examination of uterine adnexa does not require filling the bladder. Wrong, both color ultrasound and black and white ultrasound use the bladder as a transmissive window to observe the pelvic organs, so both color ultrasound and black and white ultrasound need to fill the bladder. Myth 3: You can check the gallbladder after a meal, except for the gallbladder. Wrong, after meal, abdominal gas interference, the pancreas and bile ducts can not be well displayed, so we recommend that patients in the examination of abdominal organs is best after 8 hours of fasting, in order to obtain the best examination results. Myth 4: Ultrasound has an effect on fetal development. Wrong, this conclusion exists only in laboratory studies and no clinical reports of abnormal fetal development due to ultrasound have been found, and the acoustic parameters are adjusted to a safe range when ultrasound is performed on the fetus, and there are strict regulations on fetal scan time. Myth 5: Ultrasound shows no obvious abnormalities means everything is normal. Wrong, ultrasound is not a panacea, any advanced inspection equipment can not guarantee 100% accuracy, and the disease in the earliest stage often can not show anatomical structure and morphological abnormalities, when the functional disorders and morphological failure to change ultrasound can not be explored. Myth 6: Three-dimensional ultrasound is clearer than two-dimensional ultrasound. Wrong, the most basic diagnosis of disease is still two-dimensional ultrasound, three-dimensional ultrasound can only be some unique sections of the auxiliary diagnosis, such as the fetal face sagittal section of the observation. The above has given you some basic knowledge of ultrasound, and I hope you understand the clinical use of ultrasound correctly.