On using 3D γ-analysis for IMRT and VMAT pretreatment plan QA

Chuan Wu, Kelly E. Hosier, Kristen E. Beck, Marlyn B. Radevic, Joerg Lehmann, Hao H. Zhang, Aaron Kroner, Sharon C. Dutton, Seth A. Rosenthal, Jonathan K. Bareng, Mark D. Logsdon, David R. Asche

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


Purpose: To investigate using 3D γ analysis for IMRT and VMAT QA. Methods: We explored and studied 3D γ-analysis by comparing TPS computed and EPID back-projection reconstructed doses in patient's CT images. Two 3D γ quantities, γPTV and γ10, were proposed and studied for evaluating the QA results, and compared to 2D γ (MapCheck composite: γMC). Results: It was found that when 3(global)3 mm criteria was used, all IMRT and 90 of VMAT plans passed QA with a γ pass rate 90. A significant statistical correlation was observed between 3D and 2D γ-analysis results for IMRT QA if γ10 and γMC are concerned, but no significant relation is found between γPTV and γMC. Conclusions: 3D γ analysis based on EPID dose back-projection may provide a feasible tool for IMRT and VMAT pretreatment plan QA.

Original languageEnglish (US)
Pages (from-to)3051-3059
Number of pages9
JournalMedical physics
Issue number6
StatePublished - Jun 2012


  • 3D-Gamma
  • EPID
  • IMRT
  • QA
  • VMAT

ASJC Scopus subject areas

  • Biophysics
  • Radiology Nuclear Medicine and imaging

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