Diagnostic Role of Transvaginal Sonography and Magnetic Resonance Imaging in Adenomyosis of the Uterus and its Correlation with Histopathology

BACKGROUND AND OBJECTIVE: The prevalence of adenomyosis of the uterus varies from 5% to 70%, and there is no clear consensus on its imaging diagnostic criteria. The objective of this study was to evaluate the role of transvaginal sonography (TVS), combined TVS and color Doppler (TVS-CD), and magnetic resonance imaging (MRI) in the diagnosis of adenomyosis. MATERIALS AND METHODS: This was a tertiary care hospital-based prospective study, in which 365 clinically suspected cases of adenomyosis were enrolled. All three types of imaging (TVS, TVS-CD, and MRI) were done in 233/365 patients, followed by hysterectomy in 50. Imaging features were correlated with the histopathological examination (HPE), which was taken as the gold standard for the diagnosis. The diagnostic performance of each imaging modality was assessed. RESULTS: Among patients who underwent hysterectomy, 36/50 (72%) had adenomyosis on HPE, with or without associated benign gynecological abnormalities. Sensitivity, specificity, positive predictive value (PPV), negative PV (NPV), and diagnostic accuracy (DA) of MRI were higher than that of TVS-CD (91.67% vs. 77.78%, 85.71% vs. 78.57%, 94.29% vs. 90.32%, 80% vs. 57.89%, and 90% vs. 78%, respectively). TVS alone had lower diagnostic performance (specificity: 64.29%, PPV 84.85%, NPV 52.94%, and DA74%) than TVS-CD, but equal sensitivity (77.78%). Heterogeneous myometrium was the most sensitive (80.56%), while myometrial cyst was the most specific (92.86%) TVS feature. The maximum junctional zone thickness ≥12 mm was the most sensitive (97.22%), while the hyperintense myometrial focus was the most specific (100%) MRI feature. CONCLUSION: TVS-CD should be used as an initial diagnostic imaging modality in clinically suspected cases of adenomyosis; however, MRI due to better diagnostic efficacy should be the imaging modality of choice before subjecting such patients to hysterectomy.