Ultrasound (sonography)

Ultrasound (sonography) uses high-frequency sound waves and a computer system to project images from inside the body cavity onto a monitor screen. The image is produced when the sound waves bounce off internal organs in a way similar to the sonar used by bats and naval vessels. Ultrasound can record both moving pictures and still pictures. Gynecological ultrasound can be done through the abdomen (transabdominal) or by placing a probe inside the body through the vagina (transvaginal).

The Procedure
Ultrasound is a painless procedure that takes about 15 minutes. There are no known risks for this procedure.

For a transabdominal ultrasound, you will be asked to change into a hospital gown and lie on an examination table. The sonographer will apply a clear gel to the lower abdomen. The transducer (the instrument that produces the sound waves) cannot penetrate air. The gel eliminates any air pockets between the transducer and your skin. The sonographer moves the transducer across the abdomen to produce images of the pelvic organs on the computer screen. You may be asked to drink several glasses of water before your examination. A full bladder provides a better view of the uterus, ovaries, and bladder wall.

For a transvaginal ultrasound, you will be asked to lie with your knees up and your feet in stirrups, as for a pelvic exam, while the sonographer inserts the lubricated tip of the wand-shaped transducer into your vagina. The ultrasound transducer is smaller than the speculum used for a pelvic examination. It is inserted about three inches into your vagina and moved to different positions to provide views of the uterus and ovaries.

Reasons for an Ultrasound
Ultrasound can provide views of the uterus, ovaries, kidneys and bladders. It is frequently used to scan for cysts and tumors, to look for abnormalities in the uterus and fallopian tubes, to diagnose ectopic pregnancies, and to serve as a guide for biopsies and ovarian cyst aspiration. Transvaginal ultrasound is used as a screening tool for ovarian cancer.

Other Types of Ultrasound:
3-D Ultrasound – This type of ultrasound uses special equipment to produce images that have depth as well as length and width. These images look more like a photograph than do conventional ultrasound images.
4-D Ultrasound – A 3-D ultrasound done over time to produce a moving picture is called a 4-D ultrasound. The four dimensions are length, width, depth, and time.