PALO ALTO, Calif. -- September 30, 2004 -- A leading private clinic in Switzerland has become the second European hospital to install the new On-Board Imager(tm) system for image-guided radiation therapy (IGRT) made by Varian Medical Systems (NYSE: VAR). The new radiotherapy department at the Hirslanden Klinik in Aarau has been equipped with one of the most advanced and sophisticated radiotherapy systems in the world today. In addition to the On-Board Imager, which is used to fine tune patient positioning at the time of treatment, the system incorporates Varian’s RPM(tm) Respiratory Gating system, which tracks tumor motion and turns the treatment beam on and off as the tumor moves in and out of range. By “gating” the treatment beam, doctors are able to deliver a more precise dose to the tumor, and avoid more of the surrounding healthy tissues.
“This clinic is really outstanding,” says Dr. Peter Cossmann, chief physicist. “The special combination of advanced technologies that has been implemented here make it one of the most modern and advanced radiotherapy clinics in the world.”
Varian's On-Board Imager is a digital imaging device mounted on the treatment machine via robotically controlled arms that operate along three axes of motion. No other imaging device for radiotherapy has this range of motion. This allows the imager to be positioned optimally for the best possible view of the tumor and surrounding anatomy. The device produces high-resolution images of the tumor, and it can also track tumor motion to provide doctors with a clear indication of exactly how a tumor will move during treatment due to normal breathing and other physiological processes.
Prior to the advent of IGRT and tools like the On-Board Imager and respiratory gating, radiation oncologists have had to contend with variations in patient positioning and with respiratory motion by treating a larger margin of healthy tissue around the tumour. IGRT is expected to enable doctors to minimize the volume of healthy tissue exposed to the treatment beam. Dr. Cossmann and his colleagues at Aarau are currently using the On-Board Imager to adjust and verify positioning on 15 patients a day and the intention is to gradually increase this to 35 per day.
“The clinic treats all cancers but we have a particular interest in treating thoracic and lung cancers using the On-Board Imager and respiratory gating,” adds Dr. Cossmann. “This is proving to be a very effective way of increasing the dose while minimizing damage to other organs.”
As well as such key Varian IGRT solutions, the clinic’s Radio-Oncology Department has also implemented an entirely paperless and filmless working environment, utilizing Varian’s VARiS Visionä oncology management system, which offers electronic patient charts.
“I have a great deal of pride about this place,” says Dr. Cossmann. “Our goal was to combine the best possible technologies on the market for the benefit of cancer patients and we have achieved that.”