Magnetic resonance imaging-guided focused ultrasound ablation of uterine fibroids: early clinical experience.
OBJECTIVE
The aim of this study was to assess the feasibility and effectiveness of magnetic resonance (MRI)-guided focused ultrasound (MRIgFUS) ablation for uterine fibroids and to identify the candidates for this treatment.


METHODS
A total of 48 patients with a symptomatic uterine fibroid underwent MRIgFUS. The percent ablation volume was calculated, and the patients' characteristics and the MR imaging features of the fibroids that might predict the effect of this treatment were assessed. Changes in the symptoms related to the uterine fibroid were assessed at 6 and 12 months.


RESULTS
The planned target zone were successfully treated in 32 patients with bulk-related and menstrual symptoms but unsuccessfully treated in the remaining 16 patients. These 16 patients were obese or their uterine fibroid showed heterogeneous high signal intensity on T2-weighted images. The 32 successfully treated patients were followed up for 6 months. At the 6-month follow-up, bulk-related and menstrual symptoms were diminished in 60% and 51% of patients, respectively. Among them, 17 patients were followed up for 12 months, and 9 of them who showed alleviation of bulk-related symptoms at 6 months had further improvement. The mean percent ablation volume of those nine patients was 51%. In 5 (33%) of the 15 patients with alleviation of menstrual symptoms at 6 months, the symptoms became worse at 12 months. There was a significant difference in the mean percent ablation volume between patients with alleviation of menstrual symptoms and those without (54% vs. 37%; P = 0.03).


CONCLUSIONS
MRIgFUS ablation is a safe, effective treatment for nonobese patients with symptomatic fibroids that show low signal intensity on T2-weighted images. Ablation of more than 50% of the fibroid volume may be needed with a short-term follow-up.
Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita 565-0871, Japan. k-mikami@ra3.so-net.ne.jp
Koji
K
Mikami
Takamichi
T
Murakami
Atsuya
A
Okada
Keigo
K
Osuga
Kaname
K
Tomoda
Hironobu
H
Nakamura
D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D007889:Leiomyoma / Q000628:therapy*; D053783:Magnetic Resonance Imaging, Interventional; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome; D014464:Ultrasonic Therapy; D014594:Uterine Neoplasms / Q000628:therapy*
D003287:Contrast Media; D019786:Gadolinium DTPA