Transvaginal sonography in the diagnosis of adenomyosis: which findings are most accurate?

Objectives: To evaluate the accuracy of various transvaginal sonographic findings in adenomyosis by comparing them with histopathological results and to determine the most valuable sonographic feature in the diagnosis of adenomyosis.

Methods: In this prospective study, 70 consecutive patients scheduled for hysterectomy underwent preoperative transvaginal sonography. If at least one of the following sonographic features was present, a diagnosis of adenomyosis was made: heterogeneous myometrial echotexture, globular-appearing uterus, asymmetrical thickness of the anteroposterior wall of the myometrium, subendometrial myometrial cysts, subendometrial echogenic linear striations or poor definition of the endometrial-myometrial junction. The sonographic features were compared with the histopathological results.

Results: The prevalence of adenomyosis was 37.1% (26/70 patients). The sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and accuracy of transvaginal ultrasound for the diagnosis of adenomyosis were 80.8%, 61.4%, 55.3%, 84.4% and 68.6%, respectively. We found that a regularly enlarged uterus with a globular appearance, subendometrial echogenic linear striations and myometrial cysts had the highest accuracy for the diagnosis of adenomyosis. Of all findings evaluated, heterogeneous myometrium was the most common in patients with adenomyosis (21/26 patients), but it had a poor specificity. The presence of subendometrial linear striations was the most specific sonographic feature (95.5%) and it had the highest PPV (80.0%) for the diagnosis of adenomyosis.

Conclusions: The presence of subendometrial echogenic linear striations, a globular configuration and myometrial cysts on transvaginal ultrasound supports the diagnosis of adenomyosis. Among the transvaginal ultrasound diagnostic findings of adenomyosis, subendometrial linear striations have the highest diagnostic accuracy.