Background: Implementation of an important step for quality assurance in irradiation of the craniospinal axis was made through changes in the irradiation technique. Crucial improvements in patient positioning and the possibility of taking portal films of the field junctions are described.
Material and methods: A box for the positioning of the head of the patient in has been developed. In combination with vacuum cushions, it is a cheap method for the individual and secure positioning of the patient in prone position. Furthermore, a method for taking portal films of the field junctions between the lateral cranial and the upper dorsal spinal field as well as between the two dorsal spinal fields is described.
Discussion: The use of the "Bonner Box" improves the patient positioning with respect to reproducibility, setup time and comfort. The documentation of the field junctions in craniospinal irradiation, which is described for the first time, is an important tool for quality assurance.