Gynecological ultrasound is a non-invasive ultrasound examination of the internal female genital system (uterus and ovaries). It is generally used as a support for the gynecological examination. It also applies in the identification of anatomical conditions at oncological risk (for example ovarian masses), anatomical functional conditions (infertility, menstrual cycle or menopausal disorders) and post-surgical monitoring.

 

Gynecological ultrasound can be performed through two approaches:

 

• Transvaginal ultrasound: the patient is lying down and has just emptied her bladder. A probe is introduced inside the vagina covered by a disposable probe cover. The ultrasound image is projected on a screen that the patient can possibly view. This examination method, although more annoying (but not painful), represents the most suitable method of execution in most clinical conditions as it guarantees a better visualization of the genital system and a better resolution of the image.

• Trans-abdominal ultrasound: after having adequately filled the bladder (drinking a bottle of water) the probe is placed on the abdomen. The image quality is reduced due to a matter of ultrasound penetrance through the abdominal wall. Furthermore, some conditions such as obesity, thickened abdominal wall or intestinal meteorism (gas in the intestine) can further increase the acoustic impedance to ultrasound further reducing the quality of the image. This method is used for specific diagnostic questions (for example voluminous abdominal masses) or in the case in which it is not possible to perform the examination by the transvaginal route.

 

The gynecological ultrasound examination can be performed at any time of the menstrual cycle or in menopause. Sometimes, there may be an indication to perform it in a particular phase of the cycle.

 

Gynecological ultrasound has its limits. For example, in about 10% of ultrasound examinations, the endometrium (the internal portion of the uterus) will not be visible. In post-menopause, it is possible not to be able to see the ovaries as these tend to atrophy and be "lost" between the intestinal loops. The accuracy of gynecological ultrasound, even if conducted in the best-operating conditions, is not absolute (i.e. there are falsely negative and falsely positive cases) Although transvaginal ultrasound is an accurate method in the differential diagnosis between benign and malignant masses, the use of this examination in the screening of gynecological malignancies is not currently supported by valid scientific data. In all cases, ultrasound does not always allow to exclude a pathology affecting the uterus or ovaries with certainty.

 

Sometimes it may be useful to repeat the examination after some time, in order to evaluate the evolution of the aspects detected or integrate the results with those of other diagnostic imaging methods (CT, magnetic resonance imaging). Similarly, it may be necessary to perform blood tests or a diagnostic hysteroscopy.

 

It is indicated as an annual screening in both fertile and postmenopausal women as a completion of the gynecological examination.

 

Sources and bibliography

 

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