An ultrasound exam (or "sonogram") is a painless diagnostic technique that makes use of how sound waves travel through the body. When sound waves pass through the body, they bounce off tissues and organs in certain ways. The reflected waves can be used to make images of the organs inside. The sound waves don't hurt the body, and there's no radiation.
Ultrasound imaging may be done in the health provider's office, in the hospital, or in an outpatient facility. The reason for the study and details of the case will help decide where the test should be done.
In most cases, very little needs to be done before an ultrasound exam. The patient lies on the exam table. A clear, water-based gel is put on the skin over the part to be checked. This gel helps the sound waves go through the body. A hand-held probe ("transducer") is then moved over that part. For prostate ultrasound exams, a specially designed probe is inserted into the rectum.
There is no risk of radiation with this study. The patient can return to daily tasks right away after the test.
Some exams, such as a bladder scan for residual urine, don't call for the user to have a lot of experience. Other exams, such as ultrasound of the kidneys, testicles or prostate, call for the user to have more experience or skill.