Magnetic Resonance Imaging–Guided Focused Ultrasound Treatment of Symptomatic Uterine Fibroids

Abstract

Objectives: The aim of this study was to assess the impact of the advanced technology of the new ExAblate 2100 system (Insightec Ltd, Haifa, Israel) for magnetic resonance imaging (MRI)Yguided focused ultrasound surgery on treatment outcomes in patients with symptomatic uterine fibroids, as measured by the nonperfused volume ratio. Materials and Methods: This is a retrospective analysis of 115 women (mean age, 42 years; range, 27Y54 years) with symptomatic fibroids who consecutively underwent MRI-guided focused ultrasound treatment in a single center with the new generation ExAblate 2100 system from November 2010 to June 2011. Mean T SD total volume and number of treated fibroids (per patient) were 89 T 94 cm 3 and 2.2 T 1.7, respectively. Patient baseline characteristics were analyzed regarding their impact on the resulting nonperfused volume ratio. Results: Magnetic resonance imagingYguided focused ultrasound treatment was technically successful in 115 of 123 patients (93.5%). In 8 patients, treatment was not possible because of bowel loops in the beam pathway that could not be mitigated (n = 6), patient movement (n = 1), and system malfunction (n = 1). Mean nonperfused volume ratio was 88% T 15% (range, 38%-100%). Mean applied energy level was 5400 T 1200 J, and mean number of sonications was 74 T 27. No major complications occurred. Two cases of first-degree skin burn resolved within 1 week after the intervention. Of the baseline characteristics analyzed, only the planned treatment volume had a statistically significant impact on nonperfused volume ratio. Conclusions: With technological advancement, the outcome of MRI-guided focused ultrasound treatment in terms of the nonperfused volume ratio can be enhanced with a high safety profile, markedly exceeding results reported in previous clinical trials.

Renal ablation using magnetic resonance-guided high intensity focused ultrasound: Magnetic resonance imaging and histopathology assessment

“…The effects of respiratory motion, boney obstacles and/ or shallow angle of focused spots on the variability of ablated volumes and depth cannot be excluded; and (3) the used energy for the kidneys caused minor collateral damage in the skin, subcutaneous muscles and intestine in two animals. Similar cutaneous and subcutaneous tissue burning was previously observed in patients [9] . In conclusion, this MRI and histopathology study provided good assessment of non-tumor renal ablation created by MRg-HIFU.…”

“…In order to exploit the use of hyperthermia in the clinic, investigators need a better understanding of heating effects on various cell types and tissues [8] . MRg-HIFU has been used for treating uterine fibroids [9,10] , palliation of bone metastases [11] , ablation in the brain tumor through the skull [12] , breast cancer [13,14] , prostate [15] and hepatocellular carcinoma [16] . The safety and feasibility of using extracorporeal HIFU in treating patients with kidney tumor has been demonstrated [17,18] .…”

White Paper: Interventional MRI: Current Status and Potential for Development Considering Economic Perspectives, Part 2: Liver and Other Applications in Oncology

“…Treatment takes approximately 2 to 3 hours, can be performed on an outpatient basis under analgosedation and most patients can usually resume normal activities the following day [51]. The method has undergone further technical development in recent years to improve safety and efficiency [52,53]. Clinical studies show that the results are comparable with other uterus-preserving treatment methods [54].…”

Genitourinary Applications of MR-Guided High-Intensity Focused Ultrasound

“…Further with newer technologies, higher NPV ratios have become routinely feasible in clinical practice with minimal adverse events [32]. A 41 % HIFU live pregnancy and 28 % spontaneous abortion rate have been reported after HIFU [33 •• ].…”