Diffuse adenomyosis: comparison of endovaginal US and MR imaging with histopathologic correlation.

Abstract

PURPOSE: To compare the accuracy of endovaginal ultrasound (US) and magnetic resonance (MR) imaging in the diagnosis of adenomyosis. MATERIALS AND METHODS: The authors prospectively studied 119 consecutive patients undergoing hysterectomy. The endovaginal US scans and MR images were interpreted independently in a double-blind fashion. Imaging findings were compared with those at histopathologic examination. RESULTS: At histopathologic examination, adenomyosis was found in 28 of the 119 patients (24%). Sensitivity and specificity was 89% for endovaginal US and 89% for MR imaging. The positive predictive value was 71% for US and 65% for MR imaging. The negative predictive value was 96% for US and 95% for MR imaging. There was no statistically significant difference between the sensitivities (P = .65) and specificities (P = .75) of endovaginal US and MR imaging. The mean junctional zone (JZ) thickness on MR images in patients with and without proved adenomyosis was 15.0 mm +/- 4.9 and 7.7 mm +/- 3.3, respectively (P < .0001). When receiver operating characteristic curves were applied retrospectively, the optimal JZ value for the diagnosis of adenomyosis with MR imaging was > or = 12 mm. CONCLUSION: Endovaginal US was as accurate as MR imaging in the diagnosis of uterine adenomyosis. Use of a JZ thickness of > or= 12 mm should further optimize the diagnostic accuracy of MR imaging.