Correlation of Reductions in Perfused Fibroid Volume With Subsequent Reductions in Total Fibroid Volume After Transcervical Radiofrequency Ablation

Study Objective
To determine if the extent of fibroid ablation, as reflected in a decrease in perfused fibroid volume three months after treatment, correlates with a reduction in total fibroid volume at 12 months.

Design
Prospective, longitudinal, multicenter, single-arm trial.

Setting
Academic and community hospitals in the United Kingdom, The Netherlands and Mexico.

Patients
27 women with heavy menstrual bleeding secondary to fibroids.

Intervention
Radiofrequency ablation guided by built-in intrauterine sonography (the Sonata™ System).

Measurements and Main Results
The 27 patients had a total of 42 fibroids that were ablated. Contrast-enhanced MRI was used to determine the perfused and total fibroid volumes at baseline, at 3 months post-treatment and again at 12 months post-treatment. All MRI measurements were performed at a single core laboratory (MedQIA, Los Angeles, USA). Using a least squares method for linear regression, the change in total fibroid volume at 12 months as a function of the change in perfused fibroid volume at 3 months was found to have a correlation coefficient (R2) of 0.7518. The linear equation describing this relationship was y = 0.9919x + 0.0052.

Conclusion
There is a positive correlation between the reduction in perfused fibroid volume noted on contrast-enhanced MRI at 3 months after transcervical radiofrequency ablation and the reduction in total fibroid volume at 12 months. Thus, as larger portions of a fibroid are ablated, there will tend to be a greater reduction in total fibroid volume at 1 year.