New technologies enable accurate, non-invasive lung tumor treatment without additional intra-fraction radiation imagingAfghanistan — Wednesday, April 7, 2010
Elekta has introduced an advanced solution for treating lung tumors that enables doctors to visually confirm the tumor’s position during the breathing cycle. This new technology treats the lesion with a continuous radiation beam, increasing therapy accuracy while using less imaging radiation during treatment delivery.
Lung tumors have been among the most challenging radiation therapy targets because the patient’s breathing causes tumors to move. New research has shown that the lung tumor shifts position from day to day during the course of treatment (baseline shift).1 Doctors often have had to use external skin surface markers or implanted markers to estimate lung tumor position during the breathing cycle and then apply the beam only during certain points in the patient’s respiration. These strategies require complex, time-consuming planning and delivery, and prolong treatment with an inefficient stop-start (i.e., gated) beam delivery.
“Elekta’s XVI Symmetry ™ and XVI Intuity™ completely change the approach when it comes to the treatment of lung tumors,” says Dee Mathieson, Senior Vice President, Oncology Business Line Management. “Symmetry provides tools to manage shifts in the relative positions of the tumor and organs-at-risk during the respiratory cycle, and Intuity ensures that not only is the tumor’s position accounted for, but also the position of nearby healthy critical structures. This contributes to a more patient-friendly and safe treatment.”
Intuity and Symmetry were developed in collaboration with Elekta’s clinical partner, The Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AvL), in Amsterdam. Both XVI tools are designed to significantly enhance the clinician’s confidence in aggressively treating cancer, while limiting undue exposure to healthy tissues. The results can lead to better patient outcomes and quality of life.
XVI Symmetry and XVI Intuity are feature sets of version 4.5 of Elekta’s X-ray Volume Imaging (XVI) package of software solutions for Image Guided Radiation Therapy (IGRT). XVI 4.5 recently received 510(k) clearance and CE marking, to enable sales and distribution in the United States and Europe.
XVI Symmetry—Managing Respiratory Motion
“Traditional external markers in lung cancer radiation therapy don’t account for baseline shifts of the tumor throughout the course of the treatment sessions,” says NKI-AvL’s Jan-Jakob Sonke, Ph.D., who with his colleagues developed the technology behind Symmetry.1-4 “Symmetry captures image data during the breathing phase and performs sophisticated computations to provide 4D data. This data helps to visualize the tumor position in each phase of the respiratory cycle to arrive at an average position of the tumor for each treatment.”
The benefits are accounting for baseline shifts and the ability of the physician to treat using reduced “margins” (i.e. better fit of dose) around the tumor—by virtue of enhanced knowledge of the tumor’s position on a day to day basis.
XVI Intuity—Image Guidance for Both Tumors and Critical Structures
The key to safe, effective radiation therapy is often to maximize the dose to the tumor, and to minimize the dose to critical structures, or organs-at-risk. Imaging technology integrated in Elekta IGRT systems has revolutionized the physician’s ability to achieve this goal.
XVI Intuity extends image guidance by better enabling critical structure avoidance, which allows doctors to understand the positional relationship between the target and organs-at-risk. This ensures that anatomical changes and corrections to set-up errors have not inadvertently put critical structures into the radiation beam’s path.
For more information on Elekta’s next generation SBRT visit: www.elekta.com/lung-sbrt
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