Diffusion-weighted imaging for evaluation of uterine arterial embolization of fibroids.

Purpose: To determine whether diffusion-weighted imaging (DWI) characteristics could predict the effectiveness of uterine arterial embolization in treatment of fibroids.

Methods: This retrospective study included 17 women (27 fibroids) who underwent uterine arterial embolization for fibroids. MR imaging (1.5 T) was performed before, 1 week and 6 months after uterine arterial embolization. The volume, T2 signal, T1 signal, enhancement after contrast media injection, DWI signal (b = 500 s/mm(2) ) and apparent diffusion coefficient (ADC) were assessed for fibroids.

Results: DWI signal or ADC, whether before or 1 week after the procedure, did not show a statistical relationship to success of uterine arterial embolization. On the 1-week follow-up, 22% of fibroids enhanced vs. 85% on baseline, P < 0.0001 and DW signal intensity increased. ADC values in fibroids decreased between baseline and 1-week (1.61 vs. 1.53 × 10(-3) mm(2) /s, P = 0.13). On 6-months, ADC continued to decrease compared with baseline (1.27 × 10(-3) mm(2) /s, P = 0.002), but with a lower signal on DWI. No changes were observed in myometrium ADC at any time point.

Conclusion: Our study demonstrated that DWI and ADC reflected early and delayed changes in fibroids after embolization; however, we were not able to demonstrate a statistically significant relationship with outcome.