InViVo-IORT - A System for Quality Control in Intra-Operative Radio Therapy

Intra operative radio therapy (IORT) is applied after the surgical removal of a tumour but still during the operation at the open situ with the objective to irradiate remains of the tumour that could not be removed surgically. Such an irridation can be performed with the Brachytherapy. In this procedure, an Iridium radiation source is placed over the remains of the tumour with the help of a carpet like "Flab" (Freiburger Flab). This Flab contains small plastic pipes, so called applicators, through which the radiation source is dragged or shifted. The accurate placement of the Flab inside the body of the patient highly depends on the experience and knowledge of the irradiation expert. Neither an individual radiation treatment planning can be performed nor a documentation of the applied isodose in the CT scans can be made, because the position of the Flab is not known in its relation to a CT data set of the patient. The sacral region of the patient does not underlie anatomical changes be tween the CT scans and the open situ of the patient due to the bones of the pelvis. Therefore in this region of the body the registration of the CT scans and the patient can be performed during operation.