Jan 2 2008
Varian Medical Systems has received FDA 510(k) clearances for its RapidArc(TM) radiotherapy technology, a revolutionary advance that makes it possible to deliver image-guided, intensity-modulated radiation therapy (IMRT) two to eight times faster and more precisely than is possible with conventional IMRT or helical tomotherapy.
"RapidArc represents a major medical advance that will change the way radiation therapy is planned and delivered," says Dow Wilson, president of Varian's Oncology Systems business. "Our primary goal with this product is to improve clinical outcomes. In addition, we discovered that we could simultaneously improve treatment efficiency significantly. RapidArc should make better-quality radiotherapy a more affordable, more accessible treatment option, and enable more cancer patients to receive a higher standard of care."
RapidArc, Varian's new technology for delivering volumetric modulated arc therapy, quickly delivers a complete IMRT treatment in a single rotation of the treatment machine around the patient. The two FDA clearances for RapidArc cover the treatment hardware and the RapidArc treatment planning software module in Varian's Eclipse(TM) treatment planning system. Varian will begin taking orders for RapidArc immediately, and will begin delivering it to customers in the spring of 2008.
"Customer interest in RapidArc is tremendous," said Wilson. "This technology extends the versatility of Varian's image-guided radiotherapy system, adding volumetric arc therapy to other advanced capabilities including fixed-beam IMRT and stereotactic treatments. Doctors can use RapidArc for better prostate and head and neck treatments, and still offer fixed beam IMRT treatments with motion management for lung and breast tumors and electron treatments for patients with lymphomas and skin cancers. No other treatment technology offers this kind of versatility for customizing treatments according to each patient's specific needs."
Plan studies comparing fixed-beam and helical IMRT with RapidArc show that RapidArc can reduce the amount of non-therapeutic radiation reaching healthy tissues during treatment. For example, in the case of head and neck cancer treatments, RapidArc plans are better at protecting critical structures like the spinal cord, brain stem, eyes, optic nerve and chiasm, parotid (salivary) glands, and brain. Moreover, with RapidArc's highly efficient use of the primary beam, secondary stray radiation caused by scatter and leakage are reduced by over 50 percent on average compared with fixed field IMRT.
RapidArc Technology
RapidArc technology utilizes a sophisticated, proprietary algorithm that creates a finely-shaped IMRT dose distribution that closely matches the size and shape of the tumor. It works by varying three parameters simultaneously: 1) the speed with which the treatment machine rotates around the patient, 2) the dimensions of the beam-shaping aperture, which change continually during the treatment based on the patient's unique anatomy, and 3) the rate at which the dose is delivered. These technologies work together to make RA the most revolutionary advance in radiation therapy in terms of speed, efficiency, and conformality.
"The RapidArc planning algorithm exploits the unique characteristics of Varian's most advanced medical linear accelerators, which can deliver dose at different rates, and the multileaf collimator, which is used to shape the beam so it conforms to the shape of the tumor," said Corey Zankowski, senior director of software systems marketing at Varian. "Not only is the treatment faster to deliver, it is also easier to plan and execute. That means a higher quality treatment that's easier on the clinicians and easier on the patients."