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Image-guided stereotactic radiotherapy
12
Figure 1: The invasive head frame fixation (frame-based) (left) and the mask
immobilization (frameless approach) (right)
Finally, even with the technological advancements that enable a good dosimetrical
plan with sub-millimetric positioning of the target and immobilization of the patient,
some uncertainties in target localization and positioning are still present and must be
taken into account during a SRS treatment (9).
Stereotactic
Imaging
Replacement of the stereotactic system of external coordinates for
patient positioning by imaging =
Frameless