Magnetic Resonance guided Focused Ultrasound (MRgFUS) Technology
The ExAblate® system uses MR guided focused ultrasound technology
which combines high intensity focused ultrasound (HIFU) that heats and destroys targeted tissue non-invasively and Magnetic Resonance Imaging (MRI) which visualizes patient anatomy and continuously controls the treatment and monitors the effect on the tissue.
Ultrasound is a form of energy that passes through skin, muscle, fat and other soft tissue. High intensity focused ultrasound energy, focused on a small target volume, provides a therapeutic effect by raising the tissue temperature of the target high enough to destroy it. This is similar to how the sun′s rays ignite a flame when focused under a magnifying glass.
How Does the Treatment Work?
The focused ultrasound destroys the outer membrane of the bone that contains the pain causing nerves. When the patient, who is consciously sedated, is lying within the MRI, the bone tumor can be precisely visualized. Treatment is continuously controlled and monitored by the operator of the ExAblate system.
The focused ultrasound waves are focused down onto a small area of the painful bone. This causes the bone surface to heat up and destroys the tissue. The focused ultrasound is then targeted to another area next to the treated location and this new area is treated. The process is repeated several times until the nerves in the bone surface of the painful bone tumor are destroyed.
Experience with MR guided Focused Ultrasound
Results of an international, multi-center clinical study showed that patients who received ExAblate treatments reported significant improvement in well-being and function, along with a decrease in need for analgesics or opioids.
Promising results from previous trials on pain palliation for bone mets
have led the FDA to approve ExAblate to reduce the pain associated with bone metastases in patients who are not suitable or choose not to radiation therapy.
The physician plans and performs the MRgFUS procedure,
while the patient lies in the MRI,
continuously communicating with the physician.