2017_SBRT_Course Book

Food for thought • Traditionally, we haven t been using margins with the frame-based SRS! Ø It was (is) assumed to be perfect • Whilst we might should have used margins! Ø There are always uncertainties • Should we omit margins in frameless SRS, based on clinical experience with frame-based SRS (the dose distribution covers it)? • The concept of “ frame ” comes from the LGK, where the patient is mechanically fixed to the frame, which in turn is mechanically fixed to the delivery machine • This concept is NO LONGER VALID for linac-based or Cyberknife systems, where a direct coupling between treatment machine and patient is absent! IGRT is the only safe way to go!!!

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SBRT 2017 - D. Verellen