MR imaging features with pathologic correlation in adenomyosis

Objective To evaluate the usefulness of MRI in the diagnosis of adenomyosis. Methods Sagittal Turbo SE T 1WI, T 2WI, T 1SPIR and T 2SPIR MRI examination were performed on 30 cases with adenomyosis. Results The lesions in 12 cases with diffuse adenomyosis were demonstrated as diffusely thickened junctional zone (JZ) measured 10～35 mm (mean 18 mm) On T 2WI. 6 of them were of homogenous hypointensity. Another six had hyperintensive foci within the hypointensive lesions on T 2WI, and these hyperintensive foci could also be found on T 1WI in 5 lesions. 23 focal lesions (adenomyomas) in 18 cases were oval, irregular or round masses with hypointensity that were the same as the intensity of JZ on T 2WI. They were from 2.0-7.5 cm in diameter (mean 3.9 cm), and all but one showed ill-defined margins. 15 masses hadhyperintensive foci within the hypointensive lesions on T 2WI and 12 of 15 presented hyperintensity on T 1WI. The diffusely thickened JZ and focal masses correspond to the hyperplastic and hypertrophic musculature around the heterotopic endometrial islands. The hyperintensive foci were correlated with the heterotopic endometrial islands. The hyperintensive foci showed only on T 2WI corresponded to the heterotopic endometrial islands without hemorrhage. The hyperintensive foci shown on both T 2WI and T 1WI were the heterotopic endometrial islands with hemorrhage. Conclusion MRI is the modality of choice for the diagnosis of adenomyosis. T 2WI is the most useful sequence. T 2WI combining with T 1WI, T 1SPIR, and T 2SPIR can improve the accuracy in the diagnosis of adenomyosis.