SBRT 2016

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

38

Maciunas et al. Neurosurgery 1994 SBRT 2016 - D. Verellen