Magnetic Resonance guided Focused Ultrasound Therapy (MRgFUS).
What is ExAblate?
ExAblate is a new, radiation-free treatment that can provide prompt pain
relief for individuals suffering from bone tumor pain. Using non-invasive focused
ultrasound technology, ExAblate treats painful bone metastases by destroying
the pain-causing nerves on the bone surface surrounding the tumor.
ExAblate treatments are precision- controlled and monitored by Magnetic
Resonance Imaging (MRI) technology, ensuring a high rate of effectiveness with
minimal damage to surrounding tissue. This unique combination of technologies
is called Magnetic Resonance guided Focused Ultrasound Therapy (MRgFUS).
Non-invasive and non-toxic, for those who cannot or choose not to undergo
radiation treatments, ExAblate is the solution of choice for fast, long-lasting
bone pain relief.
ExAblate’s MRgFUS system received CE approval in 2007 for palliative treatment
of painful bone metastases.
How Does the Treatment Work?
The ExAblate system delivers focused ultrasound waves onto a small area of
the painful bone, which causes the bone surface to heat up and destroy the pain-
causing nerves. This process is repeated until all the nerves causing the pain are
The treatment is performed while lying in a specially adapted MRI scanner.
Guided by detailed images of your anatomy and the tumor, the physician is
able to pinpoint, guide and continuously monitor the treatment.
The procedure is usually performed under conscious sedation, on an outpatient
basis. Pain relief is generally experienced within three days.
One treatment is usually enough to achieve durable, long-lasting pain relief
What are the Advantages of
• Pain relief is durable - only one treatment is usually required
• Reduced pain and analgesic dependence can improve quality of life
• It is non-invasive, so no incisions or probes are needed
• Treatment is personalized to patient anatomy, pathology and response profile
• Exposure to ionizing radiation effects is eliminated
• Side-effects, if any, are minimal
What are the risks?
There are no known serious side effects.
The treatment could cause some pain or a mild skin burn. There is a possibility
of damage to other tissues, although this risk is minimized by the control attained
through MR imaging. You may experience an allergic reaction to the MRI dye or the
pain medication. There may be other risks that your doctor will discuss with you.
MR guided Focused Ultrasound Surgery (MRgFUS) technology combines
a high intensity focused ultrasound beam that heats and destroys
targeted tissue, non-invasively and Magnetic Resonance Imaging system
(MRI) which visualizes patient anatomy, and controls the treatment by
continuously monitoring the tissue effect.
Why Are MR guided Focused Ultrasound and Control Important for a Non-Invasive Procedure?
All of the above ensure safe and accurate MR guided Focused Ultrasound treatments.
Imaging in 3 Orientations for Precise Tumor Targeting
High precision anatomical MR images in 3 orientations, showing the tumor and surrounding organs, are used to position the patient and to plan the treatment to ensure:
- exact tumor targeting
- beam path visualization.
With MRgFUS, the focused ultrasound beam can be seen during the treatment to ensure that the ultrasound travels through a safe pathway to the focus. This ensures that the correct region is targeted. Sonication parameters can be adjusted to optimize the treatment and are monitored by the physician during the treatment.
MR thermometry for continuous temperature feedback
The temperature is continuously monitored during every sonication providing accurate thermal monitoring of the targeted ablation.
Temperature maps display the relative tissue temperature as a color map superimposed on an anatomical MR image. This allows the physician to observe temperature changes continuously during treatment. Based on these observed temperature changes, treatment parameters can be adjusted to ensure safe and effective thermal ablation.
Accumulated thermal dose
The system keeps track of which regions have reached thermal dose enabling the physician to determine if there has been sufficient heating.
Outcome assessment - post treatment contrast imaging for precise treatment validation