12th September 2014

Presentation at ASTRO reveals how advanced image registration helps screen for patients requiring adaptive radiotherapy

Mirada Medical software applied to state-of-the-art Adaptive Radiotherapy (ART) is the subject of an oral presentation at the annual conference of the American Society of Radiation Oncology (ASTRO). The ASTRO conference is September 14-17 in San Francisco, California and is attended by leading radiation oncology professionals from around the world.

A critical yet hugely time-consuming step in ART is the monitoring of patients throughout the course of therapy to determine which need to be replanned. This need presents a significant barrier to adoption of ART methods in the clinic. The original research, being presented by collaborators from the University Medical Center, Groningen, The Netherlands, (230, Wednesday 17, 11:15am, Room 103), examined the possibility of using advanced image registration methods to automate patient monitoring and to flag only those patients that might need further investigation. Such a method can create a significant time savings.

The study included twenty-eight locally advanced Head and Neck Cancer patients treated with IMRT. For each patient, the planning target volumes and organs at risk were contoured on the planning CT and propagated to a rescan using deformable image registration (Mirada RTx). Dose distributions of the treatment plan were calculated on both images. Replanning decisions are usually made by applying constraints to the recalculated dose on the rescan, using the warped structures. However, as a surrogate for recalculation, a dose projection method using a rigid translation applied to the original dose mapped onto the rescan was used. The same set of constraints were then applied to this resulting dose, in order to decide whether a replan was required. The results showed that the automated dose projection method correctly removed 90% of cases from further evaluation while identifying 100% of those that required investigation. This indicates rigid dose projection onto rescan CTs is a fast and automated substitute for dose recalculation since full recalculation and replanning decisions need only be made on those patients flagged by the system.

The study forms part of Mirada’s Registration AssuranceSM program, a comprehensive program for ensuring DIR quality and continuous improvement through rigorous scientific validation of technology, education, comprehensive QC tools and a commitment to ongoing development and support. Mirada recognizes the need for ongoing innovation in workflows such as adaptive replanning for RT, as well as assurance that their technology can be trusted to provide quality of care to the patient. The registration, contouring and adaptive replanning workflows used in the study are all available in the new releases of Mirada RTxTM and Mirada Workflow BoxTM. “

Adaptive Radiotherapy presents an exciting opportunity for clinics to move to the next stage of personalized treatment,” stated Dr. Timor Kadir, Chief Technology Officer of Mirada Medical. “Mirada is committed to applying its advanced deformable registration and imaging technology for making Adaptive Radiotherapy practical for every clinic and every patient.”

Mirada Medical will be demonstrating its complete suite of radiotherapy applications, and highlighting its unique Registration AssuranceSM program at ASTRO, booth #308. The researchers will be available to discuss their research and answer questions.