Red degeneration of uterine leiomyoma: MR appearance.

OBJECTIVE

Red degeneration (hemorrhagic infarction) of uterine leiomyoma can cause acute abdominal pain. This study was undertaken to identify MR features useful in diagnosing this rare complication of uterine leiomyoma.

METHODS

Magnetic resonance imaging from five patients symptomatic for 7 to 20 days with pathologic confirmation of red degeneration was retrospectively evaluated and correlated with histopathologic findings.

RESULTS

The lesions had a common MRI appearance: hyperintense rim on T1-weighted imaging (WI) and hypointense rim on T2-WI. These findings corresponded with numerous dilated vessels filled with red blood cells at the periphery of the lesion. The signal characteristics of the rim are best explained as an effect of abundant intracellular methemoglobin in these vessels.

CONCLUSIONS

Recognition of these characteristics may help radiologists differentiate symptomatic red degeneration from other clinical conditions that need surgical interventions.