GSI - Helmholtz Centre for Heavy Ion Research

R&D into software solutions for a next generation dose delivery system 

Trainee: Michelle Lis
Supervisor: Christian Graeff

Though scanned ion beams permit highly conformal treatment, and have shown successful in treatment outcomes at several tumor sites, producing the same treatment outcomes to moving tumors in the thorax and abdomen region remains a challenge. Interference between the target and beam motion as well as the changes to the
beam range with the target movement has complicated exact dose delivery. Advanced stage lung cancers and hepatic or pancreatic cancer patients could benefit tremendously from particle therapy if solutions for these challenges are found.

A next generation dose delivery system is being developed, specifically aimed at the treatment of moving tumors and potentially other non-cancer targets of the thorax. Besides faster beam delivery, the dose delivery system integrates both motion detection and mitigation methods in its core functionality. The Fellow has implemented a preliminary motion mitigation strategy, where prior knowledge of the patient anatomy and tumor motion can be incorporated in treatment plan optimization, achieving optimal tissue sparing and conformal dose coverage.

The Fellow designed and implemented advanced motion mitigation strategies, which synchronize the delivery to the target motion for safe and conformal treatments. Experimental validation has been performed with 1D periodic motion phantoms and has been repeated with sophisticated moving phantoms to show the efficacy of the strategy and confirm the safety of the system.