Uterine Leiomyoma on MRI

Leiomyoma in a 28-year-old woman. Sagittal MR images in T2W (A), T1W (B) and post-contrast T1W (C) show a large, rounded, circumscribed mass in the anterior wall of the uterus (U) that pushes the bladder (B) anteriorly. The mass demonstrates T2 hypointensity, T1 isointensity and heterogeneous enhancement. 

Facts

• Most common uterine neoplasms with prevalence up to 40% of women of reproductive age
• Benign tumors of smooth muscle with variable amount of fibrous tissue
• Surrounded by pseudocapsule and supplied by one or two large vessels
• Greater than 90% from uterine body
• Classified on their position relative to uterine wall (submucosal, intramural or subserosal)

MR Imaging Findings

• Well-circumscribed mass
• Classic signal intensity: T1 isointensity, T2 hypointensity, variable enhancement
• If T1 hyperintense, think hemorrhage
• If T2 hyperintense, think cellular leiomyoma
• If no enhancement, think partially or completely infarcted leiomyoma

References

Hricak H. MRI of the pelvis: a text atlas

Hamm B, et al. MRI and CT of the female pelvis.