Image guidance is essential for high-precision dose delivery in radiotherapy. It comprises the pre-treatment localization of the target with CT and/or MRI as well as safeguarding patient positioning during treatment. Especially the introduction of the linac mounted Cone Beam CT has opened a new realm of possibilities to enhance treatment precision, including:
* Localization of mobile tumors and organs-at-risk.
* Improvement of visualization of the relevant anatomy by application of markers in or around the tumor.
* Bio-mechanical modeling of the internal anatomy.
* Strategies for geometrical and dosimetric corrections of the treatment, including adaptive radiotherapy ( ART).
Focus is on mobile gastrointestinal/abdominal tumors (pancreatic, bladder and esophagus).
Moreover, external beam radiotherapy is combined with other techniques:
* Brachytherapy: the tumor is irradiated locally with a radioactive source
* Hyperthermia: the effect of irradiation is enhanced by heating.
Research includes modeling and quantification of the synergistic effect of these combinations.