special subjects
Ultrasonography
Procedure for Ultrasonography
If certain parts of the abdomen are being examined during an ultrasound, people may be asked to refrain from eating and drinking for several hours before the test. Normal gas build up in the intestines from eating or drinking can sometimes make ultrasound images difficult to obtain. In other instances, such as an ultrasound of female reproductive organs, women may be asked to drink a large amount of fluid to fill their bladder. Usually, the examiner places thick gel on the skin over the area to be examined to ensure good sound transmission. A handheld transducer is placed on the skin and moved over the area to be evaluated. To evaluate some body parts, the examiner inserts the transducer into the body—for example, into the vagina to better image the uterus and ovaries or into the anus to image the prostate gland. The examiner sometimes attaches the transducer to a viewing tube called an endoscope and passes it into the body. This procedure is called endoscopic ultrasonography. The endoscope can be passed down the throat to view the heart ( Echocardiography and Other Ultrasound Procedures ) or through the stomach to view the liver and other nearby organs. After the test, most people can resume their usual activities immediately. Ultrasonography and magnetic resonance imaging (MRI) do not use x-rays. 