Transvaginal Ultrasound for Gynecology

Detailed Pelvic Ultrasound and Obstetric Ultrasound

Aug 22, 2009 Diane Ursu

Transvaginal ultrasound allows for a more detailed examination of the uterus and ovaries.

"Why do we have to do this since we just looked through the belly?" This is a question that patients often ask when they find out their ultrasound needs to be done transvaginally. Transvaginal ultrasound is done by inserting a long camera into the vaginal canal. It is an incredibly useful tool for seeing the uterus and ovaries with greater detail than can be done with the abdominal transducer, or camera.

How Sound Works

Think about what it is like to talk to someone next to you. He or she will have no problem hearing you. Now, think about what it is like talking to someone who is 50 yards, or half of a football field, away. He or she probably will not hear you. The reason is that sound waves become weaker as they travel. This principle affects ultrasound.

When ultrasound is done through the abdomen, the sound waves have to travel farther to reach the organ being examined. For this reason, lower frequency ultrasound must be used so the ultrasound waves do not get too weak before returning to the transducer. The caveat with lower frequency ultrasound is that the detail, or resolution, of the picture is not very good. Transvaginal ultrasound allows the transducer to move closer to the organs, so higher frequency ultrasound can be used. This results in a clearer, more detailed picture.

Use of Transvaginal Ultrasound

Transvaginal ultrasound is used during pelvic ultrasounds. These ultrasounds typically begin with an ultrasound scan through the bladder using an abdominal transducer. The bladder is then emptied and transvaginal ultrasound is used for clearer imaging of the uterus and ovaries.

Transvaginal ultrasound is also used for early pregnancy ultrasounds. It allows the sonographer, or ultrasound tech, to image an embryo when it would not be visible through the abdomen. An embryo can be seen as early as five weeks and six days old using transvaginal ultrasound, although it is not always possible. At six weeks old, it is only one millimeter long. Using an abdominal transducer, it might be seen by seven weeks when it is four millimeters long. It may also be used during second trimester ultrasounds to examine the cervix in greater detail.

While abdominal ultrasound may show that something is wrong, transvaginal ultrasound allows the sonographer to show structures in greater detail and with greater accuracy. What shows up as a simple cyst on an abdominal ultrasound may be clearly seen as a hemorrhagic cyst, a cyst with debris in it, on transvaginal ultrasound.

The copyright of the article Transvaginal Ultrasound for Gynecology in Women’s Health is owned by Diane Ursu. Permission to republish Transvaginal Ultrasound for Gynecology in print or online must be granted by the author in writing.

Transvaginal Transducer