Advanced MRI-Guided Radiation Therapy Planning With a 3-Tesla MRI Simulator

Magnetic Resonance Imaging (MRI) Guided Advanced Procedure and Simulations (MAPS) uses MRI imaging to perform an external beam radiation therapy “simulation” (or planning procedure) for a variety of tumors for improved targeting.

This state-of-the-art suite will be the first in New England to offer this type of radiation therapy planning and brachytherapy.

What is the MRI Advanced Procedure and Simulation (MAPS) or an MRI simulator?

  • The MRI simulator is a powerful magnet (3-Tesla strength) that produces high quality medical images of the tumor and nearby organs. It is similar to an MRI, but used for radiation therapy.
  • With this state-of-the-art suite, we are able to use MRI images for specific targeting of tumors.
  • The MRI Simulator allows for better positioning for the patient. This makes treatments even more accurate.

How is MRI-guided radiation therapy planning using the MRI Advanced Procedure and Simulation (MAPS) an improvement?

Having the MRI simulator gives us the ability to generate high quality MRI images with the patient in the treatment position in their customized immobilization devices (used to hold the patient in the correct position), which further increases the accuracy of our treatments.

How will MRI-guided radiation therapy planning help me?

For radiation therapy of soft tissue tumors such as cancers of the breast, gastrointestinal, genitourinary (e.g. prostate and bladder), gynecological, head and neck, and sarcoma the detailed information provided by MRI can improve our ability to target the cancer and identify important nearby organs during the radiation therapy planning process. This will allow your doctors to deliver more precise radiation therapy that can minimize injury to surrounding organs and reduce toxicities, to improve outcomes.

How is this different from getting an MRI in the radiology department?

The MRI imaging performed for radiation therapy planning is high quality since the scanner is the same state-of-the-art scanner used for diagnostic scans in radiology. The big difference is that we will be able to perform the MRI scan with the patient in the treatment position and with their custom radiation therapy immobilization equipment in place, which will allow us to plan the radiation treatments more accurately.

Will MRI-guided radiation therapy planning replace CT-guided radiation therapy planning?

  • No, we have not yet reached the point where it entirely replaces CT-based planning.
  • We continue to use both technologies in our practice, and are performing research to gather data on their effectiveness in different situations.
  • In the future we may see CT-guided planning completely replaced by MRI-guided planning.

I am already going to receive radiation treatment, so will the MRI expose me to more radiation?

MRI does not expose the patient to any ionizing radiation.

What is MRI-guided brachytherapy?

  • Brachytherapy is a treatment procedure that uses small radioactive isotopes or seeds placed in close proximity to the tumor to deliver radiation to targets either deep within the body or to a superficial surface such as the skin.
  • Most brachytherapy is performed either with X-ray or CT guidance.
  • In the MAPS suite, we have real-time imaging of the location and placement of these implanted radiation devices. This helps us improve the quality of these procedures.

How do I find out if I am a candidate for MRI-guided radiation therapy?

Call 617-732-MR-RT or email MR-Treatment@bwh.harvard.edu to setup an appointment with one of our specialists.

Patient Experience during MRI-Guided Radiation Therapy Planning

For the first time, cancer patients in New England will have a cutting-edge option for radiation treatment, known as MRI-Guided Radiation Therapy (MRI-RT). This video highlights the two components of the new MRI-RT, a 3 Tesla MRI scanner modified for radiation therapy planning called the MR Advanced Procedure and Simulation (MAPS) unit and an integrated MRI-guided linear accelerator (MRI-LINAC). The MAPS unit includes a high-field strength (3.0T) magnet for diagnostic quality imaging for initial radiation therapy planning. The MRI-LINAC, meanwhile, is a state-of-the-art hybrid device that integrates a modified, lower-field (0.35T) MRI scanner with a linear accelerator (radiation delivery machine) to reduce the magnetic interference on the radiation beam.

What do I need to do to prepare for the MRI scan for my MRI-guided radiation therapy appointment?

A radiation oncology staff member will call you before your MRI to confirm your appointment, review the safety and medical screening questions, and give you any instructions you may need.

What if I have metal implants?

  • MRI Safety Screening Form: Our staff will review an MRI safety screening form prior to the MRI appointment with you.
  • Because MRI involves a powerful magnet, patients with metallic implants in their body can be at risk for injury from the scanner. Your team will carefully review your medical history to see if you are safe to be scanned. Some metallic implants may be safe to scan with the MRI.

Will the procedure require intravenous (IV) contrast dye?

If your MRI requires the use of an IV contrast dye, you will be asked questions to determine if you have a history of kidney disease, diabetes, lupus, multiple myeloma, or other conditions. Some patients may need a blood test to check their kidney function first.

Contrast preparation: Many of our patients receive an oral or intravenous (IV) contrast dye during their MRI to better visualize the area being scanned. The contrast agents in use today carry a low risk of allergic reaction and cause little discomfort for most people. If the doctor determines that IV contrast dye is necessary, the technologist will place an IV in your arm prior to your scan. If an oral contrast is needed, you will be asked to arrive early to take the contrast.

Should I keep taking my medications?

It is important to keep taking your medications unless otherwise instructed. For some MRI-guided procedures, you may be asked to stop taking your medicine prior to your procedure.

Should I eat or drink before the scan?

If you are having your abdomen scanned, you might need to fast 4-6 hours before the MRI exam. This will ensure that undigested food will not obscure the images. For some exams, you may be asked to drink some oral contrast when you arrive for your MRI exam. Most other MRI exams do not require you to fast or otherwise restrict your diet.

When should I arrive?

You will be asked to arrive early before your scheduled appointment to allow time to complete some required paperwork, placement of an IV if needed, and change into a hospital gown. At that time, a technologist will review the safety screening questions with you.

What should I wear?

You will need to change into a hospital gown. Our changing areas are private and there is a secure locker for your clothes and belongings. It is best if you leave valuable items at home. You will need to lock up all of your belongings, including your cell phone and credit cards. If you are wearing anything metallic, such as jewelry, dentures, eyeglasses, or hearing aids that might interfere with the MRI, we will ask you to remove them. Patients who are having a brain / head MRI should not wear make-up as some brands contain metal.

What can I expect during the MRI scan for my MRI-Guided Radiation Therapy?

Scanning: A technologist will bring you into the MRI room where you will lie down on the patient table in the immobilization devices that were made to hold you in the same position each day. You will be positioned in the large cylindrical magnet with the area to be imaged centered in the cylinder. The scanner makes a loud knocking noise when it takes the pictures. To lessen the noise, the MRI technologist will give you earplugs. In some instances, you will be offered headphones to listen to music. You will also be given a squeeze ball that sends a signal to the technologist in the observation room in case you are having a problem. You may use the squeeze ball at any time to get our attention.

The technologist will leave the room but will monitor you through the observation window just outside the scanner room and with cameras. There is also audio communication at all times through an intercom system that the technologist will use to instruct you on what is happening during the scan. It is important for you to lie very still. For some exams, you will be asked to hold your breath as the pictures are taken or the treatment is given.

Length of MRI exam: MRI scans used for radiation therapy planning may vary in length but most take 20-60 minutes to complete after you have been positioned inside the scanner.

How do I find out if I am a candidate for MRI-guided radiation therapy?

Call 617-732-MR-RT or email MR-Treatment@bwh.harvard.edu to setup an appointment with one of our specialists.

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