MRI-Guided High Focused Ultrasound (MRgFUS)
DESCRIPTIONAn integrated system providing magnetic resonance imaging (MRI)-guided focused ultrasound (MRgFUS) treatment is proposed as a noninvasive therapy for uterine fibroids and for pain palliation of bone metastases. MRgFUS is also being investigated for the treatment of other benign and malignant tumors.
Magnetic resonance-guided focused ultrasound (MRgFUS) is a non-invasive treatment that combined 2 technologies, focused ultrasound and magnetic resonance imaging (MRI). The ultrasound beam penetrates through the soft tissues and, using MRI for guidance and monitoring, the beam can be focused on targeted sites. The ultrasound causes a local increase in temperature in the target tissue, resulting in coagulation necrosis while sparing the surrounding normal structures. The ultrasound waves from each sonication are focused at a focal point which has a maximum focal volume of 20 nm in diameter and 15 nm in height/length. This causes a rapid rise in temperature (i.e., to approximately 65°C to 85°C), which is sufficient to achieve tissue ablation at the focal point. In addition to providing guidance, the associated MRI can provide on-line thermometric imaging that provides a temperature “map” that can further confirm the therapeutic effect of the ablation treatment and allow for real-time adjustment of the treatment parameters.
The U.S. Food and Drug Administration (FDA) has approved the ExAblate® MRgFUS system (InSightec, Inc., Haifa, Israel) for 2 indications; treatment of uterine fibroids and for palliation of pain associated with tumors metastatic to bone. The ultrasound equipment is specially designed to be compatible with MR magnets and is integrated into standard clinical MRI units. It includes a patient table, which includes a cradle housing the focused ultrasound transducer in a water or light oil bath. Some models of the device have a detachable cradle; only certain cradle types can be used for palliation of pain associated with metastatic bone cancer.
To date, the primary clinical application of MRgFUS has been treatment of uterine fibroids (leiomyomata), one of the most common conditions affecting women in the reproductive years. Symptoms of uterine fibroids include menorrhagia, pelvic pressure, or pain. There are several approaches that are currently available to treat symptomatic uterine fibroids: hysterectomy; abdominal myomectomy; laparoscopic and hysteroscopic myomectomy; hormone therapy; uterine artery embolization; and watchful waiting. Hysterectomy and various myomectomy procedures are considered the gold standard treatment.
For treating pain associated with bone metastases, the aim of MRgFUS treatment is to destroy nerves in the bone surface surrounding the tumor. Metastatic bone disease is one of the most common causes of cancer pain. Existing treatments include conservative measures (e.g., massage, exercise), pharmacologic agents (e.g., analgesics, bisphosphonates, corticosteroids) and radiotherapy, especially conventional external beam radiotherapy (EBRT) for tumors that do not involve the nervous system.
MRgFUS is also being investigated for treatment of other tumors, including breast, prostate, and brain tumors.
In October 2004, the U.S. Food and Drug Administration (FDA) approved via the premarket application (PMA) process, the ExAblate® 2000 System (Insightec, Inc., Haifa, Israel) for “ablation of uterine fibroid tissue in pre- or perimenopausal women with symptomatic uterine fibroids who desire a uterine sparing procedure.” Treatment is indicated for women with a uterine gestational size of less than 24 weeks who have completed childbearing.
In October 2012, the FDA approved the ExAblate® System, Model 2000/2100/2100 VI via the PMA process. The intended use of the device is for pain palliation in adult patients with metastatic bone cancer who failed or are not candidates for radiation therapy. The device was evaluated through an expedited review process. The FDA required a post-approval study with 70 patients to evaluate the effectiveness of the system under actual clinical conditions.
POLICYMagnetic resonance imaging (MRI)-guided high-intensity ultrasound ablation is considered investigational. This includes, but is not limited to, its use in the following situations:
POLICY EXCEPTIONSFederal Employee Program (FEP) may dictate that all FDA-approved devices, drugs or biologics may not be considered investigational and thus these devices may be assessed only on the basis of their medical necessity.
POLICY GUIDELINESInvestigative service is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized by certifying boards and/or approving or licensing agencies or published peer review criteria as standard, effective medical practice for the treatment of the condition being treated and as such therefore is not considered medically necessary.
The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member's specific benefit plan language.
POLICY HISTORY3/31/2005: Approved by Medical Policy Advisory Committee (MPAC)
6/6/2005: Code Reference section completed
12/13/2006: Policy reviewed, ablation of tumors other than uterine fibroids as investigational added
1/8/2009: Policy reviewed, no changes
4/27/2010: Policy Title changed - "High-Intensity" and "Ablation of" were removed and "Focused (MRgFUS) for the Treatment" was added. Policy Description section was revised to add information about the ExAblate® 2000 system. Policy statement revise to add "palliative treatment of bone metastases" is considered investigational for treatment other than uterine fibroids.
04/20/2011: Policy description updated; policy statement unchanged. Added FEP verbiage to the Policy Exceptions section.
03/27/2012: Policy reviewed; no changes.
07/16/2013: Deleted "for the Treatment of Uterine Fibroids and Other Tumors" from the policy title. Policy description updated to reflect the scope of the policy. Policy statement re-written into one investigational statement; intent unchanged. Deleted outdated references from the Sources section.
SOURCE(S)Blue Cross Blue Shield Association policy # 7.01.109
CODE REFERENCEThis may not be a comprehensive list of procedure codes applicable to this policy.