Send to

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

Monitoring linear accelerator output constancy using the PTW Linacheck.

Author information

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


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.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center