MRIdian – ViewRay
MRIdian by ViewRay is the world’s first radiotherapy device with an integrated onboard MRI. It allows the treatment of tumors previously considered untreatable.
What is MRIdian (ViewRay)?
Until recently, physicians used magnetic resonance imaging (MRI) scans to see tumors, and linear accelerators (LINAC) to treat them. MRI-LINAC is a revolutionary solution that combines both technologies in the same device. MRIdian by ViewRay is the world’s first MRI-guided radiation therapy system that can image and treat cancer patients simultaneously. It is a radiotherapy solution that integrates LINAC with MRI technology in a compact design, together with software, to locate, target, and track the position and shape of tumors while radiation is being delivered.
How does MRIdian (ViewRay) work?
As with conventional radiotherapy, the patient is placed on a table, and MRI is performed on the targeted tissues. The tumor area and surrounding healthy tissues can be visualized clearly with the aid of MRI. Real-time imaging helps physicians control the treatment process during irradiation. If a clinically important movement of targets or healthy tissues is detected, physicians can adjust the target and replan the treatment while the patient is still on the treatment couch. A new MRI scan is performed before each treatment session, allowing for tailored treatment based on the patient’s daily anatomy.
Patients play an active role in MRI-Linac radiotherapy. During treatment, the patient can monitor the tumor on a screen and adjust their breathing to keep it within the marked frame. When the treatment session is over, the patient can go home immediately.
Differences between MRIdian and conventional LINAC-based treatments
MRIdian is a new technology for advanced radiotherapy. The new therapeutic method addresses the limitations of radiation oncology. Due to its ability to see the soft tissues well and monitor radiation delivery in real-time, MRI-guided radiation therapy allows for the treatment of small or hard-to-reach tumors, tumors located close to critical structures, or tumors that move (for example, with breathing). Compared to conventional radiotherapy, MRIdian offers advanced features:
- Provides continuous imaging in real-time
- Enables the physician to see tumors clearly, even in soft tissues
- Allows access to hard-to-reach or moving tumors in the chest or abdomen
- Tracks the movements of tumors and healthy tissues during radiation treatment
- Provides real-time, on-table adaptive radiotherapy planning
- Provides video recording during the treatment process and allows for visualization of progress
- Enables the delivery of high doses and precise irradiation
- Avoids the need for invasive and costly markers and tissue expanders
Advantages of MRIdian (ViewRay)
The MRIdian LINAC system provides significant benefits for certain patients:
- Enhanced real-time tumor visualization
- Tight margins and minimal radiation to surrounding healthy tissues
- Few treatment sessions
- Minimal side effects for the patient
- Excellent safety and efficacy of radiation therapy
- Improved outcomes for hard-to-treat tumors
Conditions Treatable with MRIdian (ViewRay)
MRI-LINAC can be used for all tumors throughout the body. However, it provides significant advantages for patients with lung cancer, prostate cancer, abdominal cancer, liver tumors and metastases, and pancreatic cancer in particular. Its range of applications includes breast, periaortic, lung, kidney, bladder, and pelvic lymph nodes, head and neck area, bile duct, stomach, cervix, adrenal gland, orbit, bone, spleen, gyn pelvis, thorax, aortic arch, pancreas, heart, prostate, mesenteric, abdomen (soft tissue), neck, rectal, parotid gland, pelvis, spine, esophagus, thyroid, colon, liver, extremity, mediastinal, pelvic, soft tissue pelvic, brain, uterine, flank, gall bladder, and lingual lymph nodes, nasopharynx, ovaries, rib, and thymus.
What Types of Cancer are Treated by MRIdian?
MRIdian is used mostly for the treatment of:
- Head and neck cancers
- Lung cancer
- Prostate cancer
- Liver cancer
- Gynecologic cancers
- Gastrointestinal cancers
- Pancreas cancer
- Bile duct cancer (cholangiocarcinoma)
- Breast cancer
- Kidney cancer
- Soft tissue sarcomas
MRIdian provides an opportunity to see and track soft tissues and tumors in real-time. This enables re-planning of the treatment course on the table if need be. MRIdian can be used in all tumors but is especially advantageous in the locations where the body has some degree of motion: the tumors located in the abdomen, the thoracal regions, etc. Tumors in these regions are in motion even during normal breathing patterns. Therefore, the tumor area and surrounding healthy tissues can be visualized clearly (are clearly visible) with the aid of the MRIdian. In case of detecting a clinically significant movement of targets or healthy tissues, physicians are able to adjust the target and re-plan the treatment while the patient is still on the table. Keeping an eye on the findings of each treatment session, a new MRI scan could be performed before the other one. It allows a tailored treatment in accordance with the patient’s daily anatomy.
With MRIdian, it is possible to track the tumor and give the treatment at the right time and target position. It allows treatment of hard-to-reach tumors, tumors located close to critical structures, or tumors that can move during normal bodily functions such as breathing. This makes MRI-Guided Radiation Therapy unique and more effective compared to other technologies. Moreover, MRIdian therapy offers better results with little to no side effects or complications.
What Should I Expect After MRIdian Treatment?
After your tumor board decides to carry out the treatment with MRIdian, the treatment journey consists of 4 steps: simulation, planning, treatment, and follow-up. MRIdian treatment is completed between 1-5 sessions. With MRIdian, it is possible to escalate the dose while keeping the healthy tissue unharmed. Thus, MRIdian radiotherapy is finalized with fewer fractions than conventional radiotherapy. Depending on tumor localization and type, one session would take approximately between 25 to 60 minutes. You can go to their homes or hotel rooms after each treatment session. After a week, you come back to the hospital again for a control examination and tests. According to your tumor, the succeeding treatment can be planned. For instance, if MRIdian is used for a pancreatic cancer case, the patient may need to be operated on after the treatment. On the other hand, if a patient suffers from localized prostate cancer, he can cure with MRIdian treatment and will no longer need additional treatment.
What are MRIdian’s Disadvantages?
All radiotherapy treatments may bring about some side effects. Side effects of MRIdian are roughly similar to other radiation treatments. They are typically temporary and may result in respiratory, digestive, urinary, or reproductive system issues. In addition, some patients are likely to suffer from fatigue, nausea, skin irritation, and hair loss. However, MRIdian sees and tracks healthy tissues and tumors in real-time, and consequently, it delivers the radiation beams to the tumor with utmost accuracy and causes minimum damage to healthy tissues. During the treatment, the radiation beam solely targets the tumor. If the tumor is out of the treatment area, the system automatically stops the beam thus decreasing the toxicity risk. Potential side effects depend on the treatment area. For instance, after the treatment of prostate cancer, some patients face temporary urine problems or loose and frequent bowel movements.
