Treatment planning for conformal stereotactic radiotherapy

Due to three dimensional planning techniques it is possible to conform the high dose region precisely to a target volume inside the brain. Special pat ient fixation and positioning systems allow a high precision in repositioni ng of the patient thus allowing fractionated stereotactic radiotherapy. Con formation can be achieved with many different irradiation techniques for ex ample with a linear accelerator using noncoplanar arcs or conformal static beams. Noncoplanar are therapy with multiple isocenters and conformal stati c beam therapy with one isocenter are compared. In both cases the DVHs of t he planning target volume and normal tissue are calculated and discussed.