What is that?
Transvaginal ultrasound or more simply TVS ( Trans-Vaginal Sonography ) is a diagnostic imaging technique, which investigates the morphology and health status of female internal genital organs.
Thanks to this examination it is possible to study uterus, ovaries and appendages, and to control pregnancy in the first trimester or in the framework of assisted reproduction techniques.
Transvaginal ultrasound is based on the emission of high-frequency sound waves (inaudible to the human ear) by a probe inserted into the vagina; as in any other ultrasound examination, the sound waves emitted by the apparatus are partly reflected by the tissues they encounter, in relation to their density (echo phenomenon). The sound waves thus reflected are picked up by the same probe that generated them, and processed by a computer to reconstruct real-time images of the anatomical regions studied.
When and why is it performed?
Transvaginal ultrasound is typically used in women with infertility problems, abnormal bleeding (which can be linked to fairly common benign causes, such as fibroids or polyps), pelvic pain of unknown origin, amenorrhea, congenital malformations of the uterus and ovaries, and before on the suspicion of tumors or infections.
It can also be used at the end of the first month of pregnancy (obstetric ultrasound) due to its ability to highlight the images of the embryo and its appendages earlier, with definition and quality of images clearly superior to transabdominal ultrasound. In later stages of pregnancy, transvaginal ultrasound may be used if better visualization of the structures adjacent to the cervix is required.
We recall that transvaginal ultrasound does not involve the use of ionizing radiation (such as those used during radiographs) and therefore does not entail any danger for the mother and the fetus.
How to do it
Transvaginal ultrasound may replace the transabdominal pelvic ultrasound (TAS), which must be rigorously performed with a full bladder to facilitate visualization and study of the pelvic organs. In contrast, transvaginal ultrasound is preferably performed with an empty bladder, saving the patient this discomfort; on the other hand, the possible discomfort produced by the probe and any manual operations of the doctor, which can be used to move the uterus and the other pelvic organs, should certainly not be overlooked. We recall in this regard that the execution of transvaginal ultrasound is very similar to a gynecological examination; the patient, in fact, lies supine on a couch in a gynecological position. The probe, covered by a kind of condom sprinkled with a sterile lubricant, is then gently inserted into the vagina. Generally no special preparation is required in the days preceding the ultrasound scan; all documentation relating to any exams previously carried out, must be taken to the clinic when the ultrasound is performed, which can be performed at any stage of the menstrual cycle.
The transvaginal approach for the investigation of the pelvic organs allows to obtain more precise and detailed images from the anatomical study of the region, given the proximity of the probe to the structures to be examined, and given the lack of organs and tissues encountered in the transabdominal way (as precisely the bladder and the adipose layer, problematic in obese women). In particular, thanks to the use of higher intonation frequencies, transvaginal ultrasonography allows obtaining anatomical details of the uterus, ovaries and endometrium that cannot be reproduced with TAS. Often, however, transvaginal ultrasound and transabdominal pelvic ultrasound are used jointly to obtain a global view of the health status of the pelvic organs. Transabdominal / transvescical ultrasound allows a better visualization of superficial and distal structures to the vagina.
