HYPERINTENSE UTERINE LEIOMYOMA AT T2-WEIGHTED MR-IMAGING - DIFFERENTIATION WITH DYNAMIC ENHANCED MR-IMAGING AND CLINICAL IMPLICATIONS

PURPOSE: To evaluate the role of dynamic enhanced magnetic resonance ( MR) imaging in differentiating leiomyomas with high signal intensity a t T2-weighted imaging. MATERIALS AND METHODS: Histologic features of 3 4 uterine leiomyomas that showed hyperintensity on T2-weighted images were compared with those of ordinary hypointense leiomyomas (n = 74). The results of treatment with gonadotropin-releasing hormone analogue were also analyzed in relation to pretreatment signal intensity. RESUL TS: Degenerated leiomyomas (n = 13) had higher signal intensity and he terogeneous architecture, but there was considerable overlap in signal intensity with cellular leiomyomas (n = 21). At dynamic enhanced MR i maging, cellular leiomyomas had marked contrast enhancement in the ear ly phase; while degenerated leiomyomas showed slight or irregular enha ncement. Cellular leiomyomas were reduced significantly in size after treatment (P =.02). The response in degenerated leiomyomas was minimal . CONCLUSION: Evaluation of signal intensity at T2-weighted imaging an d degree of contrast enhancement at dynamic enhanced MR imaging provid e useful information on the nature of leiomyomas.