I am James F. Dempsey, Ph.D., Nucl. Chem., developer of new weapons to fight cancer. My team solved “impossible” problems for treating cancer with radiation - while clearly seeing inside the patient - with a linear accelerator inside an MRI scanner, AMA!

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The radiation treatment field has invested a lot of research into making better dose distributions and delivering accurately to patients. Many advances have been made in tracking breathing motion, surgically implanting marker or gels in the body, placing balloons in orifices to immobilize tissues, using X-Ray flat-panels detectors to find markers or make “cone-beam” CTs. However, all of these approaches still do not see the actual organs and tumor in real time as they move in the body during therapy. I founded ViewRay to solve this problem. MRI scanners provide the best soft tissue visual clarity of patients organs but they are not compatible with radiotherapy accelerators. People spent decades unsuccessfully trying to combine an MRI and a Radiation beam into a single, effective medically usefully device available to treat patients. In a sense, the MRI scanner and the accelerate do not like each other. The magnetic field generated by the MRI scanner can prevent the accelerator from operating and the accelerator uses radar technology and makes radiofrequency noise that can prevent the MRI from scanning clear images.

So, we took a superconducting MRI and we split it in half opening it up, leaving the imaging volume floating in the middle where we could shoot in radiation beams while scanning. We created magnetic sleeves that could create voids in the magnetic field to protect the accelerator. Then we borrowed ideas from stealth aircraft to absorb the radiofrequency noise and eliminate it. Finally, we developed advanced software to compute and optimize dose, as well as, track tissues with real-time MRI video . This allows us to optimize, reshape, and track moving tissues so we do not miss, which is important to eradicate the tumor and spare healthy tissues. What we call the MRIdian® Linac system was FDA cleared in February of 2017. The MRIdian® an earlier generation system has been treating patients for over 3.5 years and data published at ASTRO 2017 showed significant early results in treating pancreatic cancer, known to be one of the most difficult cancers to effectively treat.

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">I am James F. Dempsey, Ph.D., Nucl. Chem., developer of new weapons to fight cancer. My team solved “impossible” problems for treating cancer with radiation - while clearly seeing inside the patient - with a linear accelerator inside an MRI scanner, AMA!