Can measurement of apparent diffusion coefficient before treatment predict the response to uterine artery embolization for adenomyosis?

OBJECTIVES

To determine the usefulness of the apparent diffusion coefficient (ADC) in predicting response to uterine artery embolization (UAE) for symptomatic adenomyosis.

METHODS

A prospective study was performed on 25 patients who underwent diffusion-weighted (DW) magnetic resonance imaging (MRI) before UAE between June 2011 and December 2012. All patients underwent 3-month follow-up MRI after UAE using non-spherical polyvinyl alcohol (PVA) particles ranging from 150 to 500 μm. Quantitative measurement of the ADC was performed for each adenomyosis. Complete response and incomplete response were defined as ≥ 90 % or < 90 %, respectively, of the non-perfusion area with adenomyosis at the follow-up MRI. The ADC values were compared between patients who achieved complete or incomplete response which was assessed according to the MRI findings after UAE.

RESULTS

Nineteen patients showed complete response, and six showed incomplete response. The ADC value ranged from 0.842 to 1.346 × 10(-3) mm(2)/s (mean 1.075 ± 0.117). The mean ADC was 1.043 ± 0.237 in the complete response group and 1.176 ± 0.429 in the incomplete response group (0.012). Using a threshold of <1.147 × 10(-3) mm(2)/s, the sensitivity and specificity of the ADC to predict success after UAE were 83.3 % and 84.2 %.

CONCLUSION

The ADC of adenomyosis may potentially predict a successful response to UAE for adenomyosis.

KEY POINTS: • Pre-procedural MRI might help clinicians predict response of UAE in adenomyosis • ADC might help predict UAE outcomes in adenomyosis • MR predictors might be used to counsel patients with symptomatic adenomyosis.