2017_SBRT_Course Book

Accuracy: Frame-based versus IGRT- frameless

• Invasive SRS is NOT without uncertainties • Factors most influencing accuracy: Ø CT image slice thickness Ø Tension / distorsion of ring due to patient weight Ø MRI distorsion Ø CT, MRI, PET image registration Ø Target definition Ø Target localization

Maciunas et al. Neurosurgery 1994

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Maciunas et al. Neurosurgery 1994 SBRT 2017 - D. Verellen