Transvaginal sonography combined with saline contrast sonohysterography in evaluating the uterine cavity in premenopausal patients with abnormal uterine bleeding.
OBJECTIVES: To evaluate whether saline contrast sonohysterography (SCSH) adds additional information to that obtained by transvaginal sonography (TVS) for predicting endometrial abnormality in premenopausal patients with abnormal uterine bleeding. PATIENTS AND METHODS: This was a two-center prospective study at a university clinic and a central hospital in Denmark. The uterine cavity was evaluated with TVS and SCSH in 470 premenopausal patients with abnormal uterine bleeding. One hundred and eighty-nine of the patients had operative hysteroscopy or hysterectomy within 4 months which provided a detailed description of the uterine cavity and was used as the true value for exclusion of polyps and submucous myomas. RESULTS: Based on normal endometrial morphology alone, the results for detection of an abnormal uterine cavity were as follows: sensitivities of TVS 0.92, SCSH 0.99; specificities of TVS 0.62, SCSH 0.72; positive predictive values of TVS 0.80, SCSH 0.85; negative predictive values of TVS 0.82, SCSH 0.98. Transvaginal sonography combined with SCSH was superior to TVS for detection of intracavitary abnormalities (McNemar test, P = 0.008). The post-test probability of there being an abnormal cavity after normal findings on TVS alone was 0.18 (0.10-0.32) and after TVS and SCSH it was 0.02 (0.01-0.11). When normal endometrial morphology was combined with an endometrial thickness of < 12 mm for evaluation of all abnormalities including hyperplasia, the diagnostic potential of TVS or SCSH was almost unchanged except for specificities, which were markedly lower (TVS 0.54; SCSH 0.57). In all the patients referred, TVS had a negative predictive value of 0.94 for identification of polyps and myomas when findings at subsequent SCSH were accepted as the true value. Transvaginal sonography reduced the pretest probability of polyps or submucous myomas from 0.35 to a post-test probability of 0.06, but missed 21% of the polyps. CONCLUSIONS: Sonohysterography was a sensitive tool and was superior to TVS used alone for evaluation of the uterine cavity in patients who underwent operative surgery for abnormal uterine bleeding. All abnormalities except one were found at SCSH, while TVS alone missed polyps and had almost one in four equivocal findings. The use of TVS, without saline contrast, left one in five of the polyps undiagnosed in referred patients with abnormal bleeding.