[Transvaginal sonography of the postmenopausal endometrium]

The most frequent symptom suggesting endometrial pathology is uterine bleeding. Each postmenopausal uterine bleeding requires fraction explorative curettage and histopathologic examination of the material obtained from the cervical canal and uterine cavity. The aim of this study was to estimate the efficacy of ultrasonography as a non-invasive method in detection of endometrial pathology in postmenopausal women, and to find out whether its more frequent use could safely decrease the number of curettages in detection of these conditions.

A prospective investigation has been performed in postmenopausal women not menstruating for more than a year, and who reported to the Department of Obstetrics and Gynaecology in Novi Sad for uterine bleeding during 1996 and 1997. Each woman underwent ultrasonographic examination by vaginal probe of 5 MHz and fraction curettage, whereas the samples from cervical canal (if obtained) and from uterine cavity were sent to histopathologic examination to the Institute of Pathology in Novi Sad. Standard statistical methods have been used for the analysis of the results. Validity of the applied ultrasonographic method in detecting endometrial pathology has been estimated by calculation of its sensitivity and specificity.

A satisfactory visualisation of the endometrium has been obtained in all 35 examined cases. The thinnest endometrium was 1 mm wide and the thickest one was--25 mm. The fraction curettage has been used to obtain material from the cervix in 2 cases and from the uterine cavity in 35 cases. In our patients with uterine bleeding, who were in the postmenopause for 13 years on average, endometrial atrophy was recorded in 17.14%, endometrial polyp in 11.43%, endometrial hyperplasia in 22.86%, endometrial adenocarcinoma in 42.86% and uterine sarcoma in 5.71%. There were 2 false negative ultrasonographic findings (2 cases of endometrial hyperplasia) and sonographic thickness less than standard versus 2 false positive cases (endometrium thicker than the limit value, 7 and 14 mm, with no real pathology) which showed that the sensitivity of the investigated method was 93.10% and the specificity was 66.66%, if the limit value for the thickness of endometrium was 3 mm.

Ultrasonographic thickness of endometrium means maximum double thickness in longitudinal plane, i.e. the distance of the opposite bordering surfaces of endometrium and myometrium. The procedure of measurements of endometrial thickness is simple in most cases. Most authors agree that there is a positive correlation between the thickness of endometrium and its pathological conditions. The most often used limit values are 3 and 4 mm. Higher limit values of endometrial thickness increase the sensitivity of the method even to 100%, but negatively affect its specificity making this method inadequate as a screening method for endometrial carcinoma. Many authors insist on introducing other criteria for evaluation of the endometrium i.e. for taking its thickness as the only criterion. Ultrasonography does not provide a completely safe differentiation between benign hyperplasia and endometrial carcinoma.

The transvaginal sonography is an efficient and acceptable, noninvasive method for early detection of endometrial pathology in postmenopausal women. The thickened endometrium during menopause is the most significant ultrasonographic criterion implicating its pathology. The vaginosonographically measured thickness of 3 mm and less, gives a relatively safe prediction of endometrial atrophy, whereas the thickness above 3 mm requires explorative curettage and histopathologic examination of the endometrium, no matter if the woman has or has not uterine bleeding. (ABSTRACT TRUNCATED)