The utility of diffusion-weighted MR imaging in differentiation of uterine adenomyosis and leiomyoma.

PURPOSE

To investigate the value of diffusion-weighted MR imaging (DWI), especially apparent diffusion coefficient (ADC) in the differentiation of uterine adenomyosis and leiomyoma.

MATERIALS AND METHODS

17 patients with uterine leiomyoma and 22 patients with uterine adenomyosis underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values, as well as ADC D-value (defined as the ADC value of high signal intensive foci minus the ADC value of lesion tissues the difference in value), were measured and compared to investigate whether they could help in the differentiation of uterine adenomyosis and leiomyoma. Histopathologic examination was conducted as the golden standard.

RESULTS

For high signal intensive foci within the lesions, uterine adenomyosis demonstrated significantly lower mean ADC value than uterine leiomyoma (1.582 vs. 2.122 × 10(-3)mm(2)/s, P=0.001). For lesion tissues, uterine adenomyosis demonstrated significantly higher mean ADC value than uterine leiomyoma (1.214 vs. 0.967 × 10(-3)mm(2)/s, P=0.001). However, there was overlap between uterine adenomyosis and leiomyoma in both measurements. Mean ADC D-value was significantly lower in uterine adenomyosis than in uterine leiomyoma (0.369 vs. 1.096 × 10(-3)mm(2)/s, P=0.000). ADC D-value had no overlap between uterine adenomyosis and leiomyoma.

CONCLUSION

DWI can be applied for the further differentiation of uterine adenomyosis and leiomyoma, in addition to routine MR imaging. ADC D-value may be a more useful tool than ADC value in the differentiation.