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

Publication/Presentation Date

6-1-2012

Abstract

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, γ(PTV) and γ(10), were proposed and studied for evaluating the QA results, and compared to 2D γ (MapCheck composite: γ(MC)).

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 γ(10) and γ(MC) are concerned, but no significant relation is found between γ(PTV) and γ(MC).

CONCLUSIONS: 3D γ analysis based on EPID dose back-projection may provide a feasible tool for IMRT and VMAT pretreatment plan QA.

Volume

39

Issue

6

First Page

3051

Last Page

3059

ISSN

0094-2405

Disciplines

Medicine and Health Sciences | Oncology

PubMedID

22755690

Department(s)

Department of Radiation Oncology

Document Type

Article

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