Therapeutic MRI Guided High Intensity Focused Ultrasound Ablation of Uterine Fibroids

Fibroids occur in 20-50% of women over 30 years of age, and with increasing size produce pain, menorrhagia, pressure, bloating and urinary and bowel compression symptoms. Fibroids may also cause infertility. Uterine leiomyomas are benign tumors originating from smooth muscle cells of the uterus and occasionally the smooth muscle of uterine blood vessels. Fibroids are estrogen dependent tumors ranging in size and number and can be found within the myometrium(intramural), at the uterine periphery extending to the serosa (subserosal), or pushing into the uterine cavity (submucosal). Symptomatic fibroids impact health and well-being of the female including lost work hours and reduced quality of life.

Current medical treatments include invasive removal of the fibroid (hysterectomy, myomectomy), drug therapy (GnRH analogues or progestin compounds) or treatments causing necrosis of the fibroid tissue such as ablation (freezing or heating) or embolization. For the relief of symptoms, women wishing to preserve the uterus may choose between invasive procedures of myomectomy, Uterine Artery Embolization (UAE), ablation or cryotherapy. The surgically invasive procedures require anesthesia, hospital stays, and long recovery periods. HIFU may offer an alternative to the above mentioned surgically invasive procedures.

In MRI-guided High Intensity Focused Ultrasound (HIFU), the ultrasound generated by the transducer is focused into a small focal tissue volume at specific target locations. During treatment, the beam of focused ultrasound energy penetrates through soft tissue and causes localized high temperatures (55°C to 70°C) for a few seconds within the target producing well defined regions of protein denaturation, irreversible cell damage, and coagulative necrosis. The MRI system allows 3D planning, means of measuring the temperature increase generated by HIFU, and the capability to quantifying the energy/dose delivered to the treatment zone.

This study is a single-center, single arm, non-randomized trial evaluating the safety, technical effectiveness and volume treatment capabilities of the Philips MR-guided HIFU system in the treatment of symptomatic uterine fibroid patients. Patients who have symptomatic uterine fibroids, who are eligible according to the inclusion and exclusion criteria and provide informed consent will be enrolled in this study. It is anticipated that women will participate in the study for a 2month period to include the screening, HIFU treatment and post treatment follow-up.

This clinical study is designed to confirm safety and demonstrate technical effectiveness of the Philips HIFU system for Uterine Fibroid treatment. Safety will be primarily assessed by evaluating minor complications and adverse events, and technical effectiveness will primarily be assessed with MRI measurements. Specific primary and secondary endpoints are detailed below.