(TVS) The transvaginal sonography (transvaginal echography or endovaginal ultrasound), uses a small vaginal transducer (5-7.5 MHz) that is inserted into the vagina to depict the inner female organs (uterus, ovaries, vessels). As a general rule, ultrasound works better when the probe is close to the area being examined. Compared with a sonogram through the abdominal wall, the transvaginal technique produces a sharper image, not only because of the close proximity to the uterus, but also because the better signal to noise ratio of the used transducer.

Indications:

The advantage of transvaginal sonography is being able to get very close to the structures of the pelvis, and thus get better images and a more reliable diagnosis.

See also Pelvic Ultrasound, Hysterosalpingo Contrast Sonography.

The usual applications of endocavitary echography (also called internal echography / endoscopic ultrasound (EUS)) are examinations of the pelvic organs through internally introduced probes, which give a more precise and correct image.
Transrectal ultrasound is a well established method for rectal or prostate carcinoma assessment.
A transvaginal echography uses a small transducer that is inserted directly into the vagina.
Used are high-frequency (10-12 MHz) for superficial organs, endocavitary echography, and intraoperative laparoscopic ultrasound. A sterile cover is slipped over the probe, which is then covered with lubricating ultrasound gel and placed in the cavitary (see Equipment Preparation).

See also Endoscopic Ultrasound, Prostate Ultrasound, Interventional Ultrasound, Transurethral Sonography, Vaginal Probe, Rectal Probe.