Varian Medical Systems Announces Milestone 1000th On-Board Imager Installation Four Years After Introduction
Lucerne, Switzerland - Varian Medical Systems is announcing the one thousandth installation of its On- Board Imager image-guidance system for targeted radiotherapy at Kantonsspital in Lucerne, Switzerland.
The On-Board Imager is a robotic X-ray device mounted on a medical linear accelerator which generates high quality images used to precisely position cancer patients for radiotherapy and radiosurgery. Before its introduction, radiation oncologists had to contend with variations in patient positioning and with respiratory motion by treating a larger margin of healthy tissue around the tumor.
"This device plays an important role in positioning of patients while treating with new advanced forms of radiotherapy such as RapidArc and stereotactic body radiotherapy," says Rolf Stahelin, marketing director of Varian's Oncology Systems business in Europe. "We installed the first production On-Board Imager at Karolinska Hospital in Stockholm in April 2004 and four years later the On-Board Imager has become the tool of choice for modern image-guided radiotherapy."
The 1000th On-Board Imager was delivered with a new Clinac iX accelerator acquired by Kantonsspital as a replacement for a 16-year-old machine. The new accelerator becomes one of three treatment machines at the hospital and it is the first equipped with image-guided radiotherapy (IGRT) capabilities.
Dr. Peter Thum, head of the hospital's radiation oncology department, said, "We recently learned that our machine would be the thousandth of its kind and we are delighted that our establishment has achieved this landmark for this advance in imaging and treatment technology. Our hospital has in the past pioneered image-guidance using gold markers for prostate patients but the new machine will enable us to introduce IGRT for many other indications."
Dr. Thum said his team were particularly interested in using the On-Board Imager's cone-beam CT capabilities to generate 3D images of prostate and head & neck tumors. "At present we have to use the planning CT and we bring the patient across to the planning department every three weeks or so to check positioning," he said. "With this capability on the treatment machines, we will be able to do this more frequently to optimise accuracy and avoid the problem of anatomical motion when the patient is transferred from the CT scanner to the treatment machine."
Kantonsspital, a state hospital serving half a million people across six states in the center of Switzerland, treats 1400 patients each year. The IGRT- equipped accelerator is undergoing installation and commissioning and clinical treatments are expected to begin in November.
On-Board Imager
Varian's On-Board Imager for IGRT enables clinicians to image and treat patients on a single machine that rotates around the patient to take X-ray images and deliver treatments from virtually any angle. The On-Board Imager device produces high-resolution images of the tumor and tracks changes in tumor shape, size or position due to shrinkage or shifting over a multi-week course of treatment, and due to respiration.
There are more than 5000 Varian linear accelerators delivering precision radiotherapy around the world and many of these can be upgraded with an On- Board Imager for IGRT. About three-quarters of all high energy accelerators shipped by Varian are equipped with an On-Board Imager.
SOURCE: Varian Medical Systems