The Accuracy of Transvaginal Ultrasonography in the Diagnosis of Endometrial Abnormalities

TLDR

Transvaginal ultrasonography is widely used to evaluate endometrial abnormalities, especially in postmenopausal bleeding, but its utility in premenopausal women with irregular bleeding is limited. The study aimed to assess the diagnostic accuracy of transvaginal ultrasonography for endometrial abnormalities in women with abnormal uterine bleeding. A prospective study of 136 women with abnormal uterine bleeding underwent transvaginal ultrasonography, hysteroscopy, and endometrial sampling, with ultrasonographic findings compared to hysteroscopic and histologic diagnoses and analyzed using ROC curves and likelihood ratios. In premenopausal women, transvaginal ultrasonography had 88 % sensitivity and 68 % specificity (cutoff 5 mm), while in postmenopausal women it achieved 97 % sensitivity and 74 % specificity (cutoff 3 mm); positive likelihood ratios were 2.8 and 3.7, negative likelihood ratios 0.18 and 0.04, and the test could reduce invasive investigations by about 40 %.

Abstract

To evaluate the diagnostic accuracy of transvaginal ultrasonography for endometrial abnormalities in women with abnormal uterine bleeding.In a prospective study, 136 consecutive patients underwent transvaginal ultrasonography, hysteroscopy, and endometrial sampling through suction curettage or directed biopsy. The ultrasonographic findings were evaluated on the basis of the final diagnosis established by hysteroscopy and histologic examination. Receiver operating characteristic curve analysis and likelihood ratios were used. Likelihood ratios algebraically combine sensitivity and specificity to describe more than the independent values themselves, specifically the change in odds favoring disease given a particular test result.In 21 of the 136 patients, hysteroscopy detected polyps or submucous myomas, which curettage failed to detect. In 67 premenopausal women, ultrasonography demonstrated a sensitivity in diagnosing endometrial abnormalities of 88% and a specificity of 68%, using a cutoff point of 5 mm of single-layer endometrial thickness. The positive likelihood ratio was 2.8 (95% confidence interval [CI] 1.66-4.55) and negative likelihood ratio 0.18 (95% CI 0.07-0.46). In 69 postmenopausal women, using a cutoff point of 3 mm, the sensitivity, specificity, positive likelihood ratio and negative likelihood ratio were 97%, 74%, 3.7 (95% CI 2.18-6.38), and 0.04 (95% CI 0.01-0.28) respectively.Transvaginal ultrasonography is an excellent first-step diagnostic method of excluding the endometrial abnormalities in women with postmenopausal bleeding but is of limited use in premenopausal women with irregular bleeding. Ultrasonography may reduce the number of invasive endometrial investigations by approximately 40%.