The ability to use MRI for treatment planning is especially beneficial for patients with prostate, brain, head/neck, spine, and soft tissue sarcomas of the extremities. These cancer types account for approximately 30-35 percent of all treated cases with radiation.
The boundaries of soft tissue tumours are difficult to discern, such that three different clinicians may define the boundaries in three completely different ways. MRI is ideally suited for imaging organs such as the brain and prostate because of its distinctive ability to visualise soft tissue. MRI allows the clinician to better define the area to be treated with radiation.
Every patient who is treated with radiation therapy must first go through a process referred to as simulation. The intent of this phase of treatment is to simulate or prepare for radiation therapy by clearly defining the tumour target area that will be treated, including the non-diseased tissue that should be spared from radiation, and the angles from which therapy should be directed.
By using MR images where the tumour is imbedded in soft tissue, clinicians are able to more clearly define the tumour boundaries and prescribe a treatment plan that is much more precise to the diseased area while sparing harmful radiation from non-cancerous tissues.
As Philips' main clinical collaborator, the Fox Chase Cancer Center in Philadelphia has been using AcQSim simulation software to incorporate MR in conjunction with CT images in a study to evaluate the differences in targeting accuracy. Since Fox Chase acquired a Philips MRI scanner for its radiation oncology department in May 2000, their studies have included more than 400 patients with prostate, brain, and other cancers.
"Can you routinely plan treatment with MR simulation and not require the CT?" asked Gary Freedman, M.D., radiation oncologist, Department of Radiation Oncology, Fox Chase Cancer Center. "This is what we hoped to determine when we began using the MR for simulation. Our studies have shown that the addition of MR images has improved our targeting accuracy particularly for tumours in soft tissue like prostate cancer."
"Using MRI for simulation, we are able to design a more precise treatment plan to target the disease and spare more normal tissue. We have been using MRI technology for all of our prostate cancer treatments for the last year. Philips' AcQSim MR is an important new breakthrough that brings together the MRI imaging and AcQSim technologies into one system. This could simplify the simulation and treatment planning process and will improve the overall accuracy and efficiency of the department, and the simulation process for the patients."
"Philips is proud to be at the forefront of MRI-based simulation and to offer clinicians a visualisation tool that is far superior to all other therapy simulation offerings on the market", stated Himanshu Shukla, Ph.D., principal staff scientist, Philips Medical Systems. "We are constantly looking for new ways to help clinicians see more of the actual tumour, while lessening the harmful effects of radiation therapy to patients."
AcQSim MR software is the latest offering in the full line of oncology imaging, simulation, and planning products from Philips Radiation Oncology Systems, a Philips Medical Systems business focused on developing systems and technologies for the radiation oncology setting. Accompanying the AcQSim MR, Philips also introduces the new Panorama 0.23T R/T open MR system, tailored for radiation therapy planning. The R/T functionality is available to the installed base of Panorama 0.23T MR systems.
In addition to AcQSim MR, Philips offers AcQSim CT, the only oncology-dedicated 85 cm bore CT; AcQSim virtual simulation; and Pinnacle3, the only fully-integrated workstation with CT Simulation, 3D planning and IMRT. With the new Panorama 0.23T R/T and AcQsim MR, Philips offers a complete solution to further improve planning of radiation treatment for oncology patients.