It is not necessary to hold urine for liver, gallbladder and spleen ultrasound, it is necessary to hold urine for fasting. Only ultrasound examination of these parts such as bladder, ureter, prostate and uterine adnexa is necessary to hold urine. Because the bladder is a cavity organ, a well-filled bladder is needed to see the bladder wall and the structures in the bladder cavity. When observing ureteral lesions, especially those at the end of the ureter, the bladder needs to be filled; when observing the prostate and uterine ovaries, the bladder needs to be held because a moderate filling of the bladder can push away the lower abdominal intestines, so that the intestines do not become gas and cause misdiagnosis or missed diagnoses. A filled bladder is anechoic and can be used as a good sound transmission window as a way to improve visual resolution. Therefore, in order to better display the image clarity, it is necessary to hold urine when doing ultrasound examination of bladder, ureter, prostate and uterine adnexa; liver, gallbladder and spleen ultrasound does not need to hold urine, it is necessary to examine on an empty stomach.