Can (1)H MR Spectroscopy be Used to Assess the Success of Uterine Artery Embolisation?

Absence of contrast on contrast enhanced MRI (CEMRI) and reduction in uterine volume at 6 months post-uterine artery embolisation (UAE) currently indicate the successful disruption of the fibroid blood supply by UAE. This study assesses whether (1)H MR spectroscopy ((1)H MRS) can also indicate the success of UAE.

20 patients with symptomatic fibroids were randomised 1:1 to undergo UAE with either Gelfoam or Embospheres. CEMRI and spectra (1.5 T) were acquired pre-, 24-h and 6 months post-UAE. LCModel was used to detect significant levels of choline, creatine and lactate in fibroid spectra. Uterine volumes were measured and paired t tests (p < 0.05) assessed volume reduction over time. Qualitative assessments of CEMRI were performed.

Choline was detected in 17/18 spectra pre-UAE, 12/14 at 24-h and 6/16 at 6 months post-UAE. Choline was not detected in the 7/7 spectra available for the Embospheres group at 6 months. These fibroids were non-enhancing on CEMRI and associated with a significant reduction in mean uterine volume at 6 months (mean/min/max 396.5/84.1/997.5 cm(3), p = 0.003). Choline was detected in 6/9 fibroid spectra available for the Gelfoam group at 6 months. Of these fibroids, four demonstrated persistent enhancement on CEMRI and two were non-enhancing. This group did not demonstrate significant uterine volume reduction (mean/min/max 117.2/-230.6/382.6 cm(3), p = 0.15). The negative minimum value indicates fibroid growth.

This study has demonstrated the potential of (1)H MRS to provide an additional marker of the success of UAE.