Do you need to hold your urine for B-ultrasound?

Do B-ultrasound whether to hold urine and do B-ultrasound position related. If do hepatobiliary spleen pancreas B-ultrasound, do not need to hold urine; do heart B-ultrasound, do not need to hold urine; do superficial parts of the body B-ultrasound, do not need to hold urine; if do kidney ureter bladder B-ultrasound, must hold urine; do uterine accessories, through the bladder, this situation may need to hold urine; for scrotal color ultrasound, do not need to hold urine; It is recommended that if you need to do B-ultrasound of the urinary system, especially the color ultrasound of the ureter and bladder, you must hold urine and empty the stool, so that you can clearly find whether there are lesions in the bladder, whether there are stones and tumors at the lower end of the ureter, etc. Women do B-ultrasound of uterine accessories, if they are in menstruation, they may need to do B-ultrasound on the pubic bladder.