Monitoring linear accelerator output constancy using the PTW Linacheck

Garry M McDermott; Andrew H Buckle

doi:10.1016/j.meddos.2009.12.001

Monitoring linear accelerator output constancy using the PTW Linacheck

Med Dosim. 2011 Spring;36(1):71-4. doi: 10.1016/j.meddos.2009.12.001. Epub 2010 Mar 26.

Authors

Garry M McDermott¹, Andrew H Buckle

Affiliation

¹ Radiotherapy Physics Section, Department of Medical Physics and Clinical Engineering, Churchill Hospital, Oxford Radcliffe NHS Hospitals Trust, Headington, Oxford, UK. [email protected]

PMID: 20346645
DOI: 10.1016/j.meddos.2009.12.001

Abstract

The PTW-Linacheck was assessed for its ability to monitor linear accelerator radiation output constancy. The key issues that were considered were the setup for daily output measurements, e.g., requirements for build-up and backscatter material, and the reproducibility and linearity of the device with linear accelerator output. An appropriate measurement setup includes a 10 × 10 cm field at 100 cm FSD, 5 cm backscatter, and no added build-up for 4 MeV electron beams, 1 cm added build-up for 6-16 MeV electron beams and 5 cm added build-up for 6-15 MV photon beams. Using this measurement setup, the dose linearity and short-term reproducibility were acceptable; however, the Linacheck should be recalibrated on a monthly basis to ensure acceptable long-term reproducibility.

Publication types

Evaluation Study

MeSH terms

Equipment Design
Equipment Failure Analysis
Particle Accelerators / instrumentation*
Radiometry / instrumentation*
Radiotherapy Dosage*
Radiotherapy, High-Energy / instrumentation*
Reproducibility of Results
Sensitivity and Specificity
Signal Processing, Computer-Assisted / instrumentation*