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CONCLUSION
More than 2200 VMAT deliveries performed with a 6 MV UNIQUE Linac were collected and analyzed. MLC motion, gantry rotation and dose delivery resulted accurate and stable: errors affecting the system were found to be small, random in nature and stationary in time.
Planar and cylindrical geometries differ not only for the numerical results of the gamma analysis but also, and mainly, because of their predictive power. The QA results obtained in planar dosimeters does not reflect accurately what happens in the patient, while QA procedure performed with cylindrical phantoms closely represents the dose discrepancies in-patient.
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Tesi di Specialità
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