Measurement possibilities using an electronic portal imaging device.
Affiliation
North Western Medical Physics Department, Christie Hospital, Manchester, UK.Issue Date
1993-11
Metadata
Show full item recordAbstract
A vital role in the quality control of radiotherapy is the use of portal imaging for verifying field size, shape, orientation and patient set-up. Coincidence of treated volume and target volume is imperative. Electronic portal imaging devices are effective at providing this verification. However, these devices are versatile enough to be used in other ways pertinent to the delivery of high quality, high precision radiotherapy. This paper examines two such ways: in assessing the reproducibility of a multileaf collimator system, and in determining exit doses in vivo. Configured as a dosimeter, the system shows a linear response with good dynamic range. Its high spatial resolution was used to show that leaf positioning was reproducible to within 0.5 mm for all tested gantry and collimator angles. Our preliminary results from this exit dosimetry technique demonstrate that, under specific conditions, doses can be determined to within 2.5% of that measured using silicon diodes or ion chambers.Citation
Measurement possibilities using an electronic portal imaging device. 1993, 29 (2):237-43 Radiother OncolJournal
Radiotherapy and OncologyDOI
10.1016/0167-8140(93)90253-5PubMed ID
8310151Type
ArticleLanguage
enISSN
0167-8140ae974a485f413a2113503eed53cd6c53
10.1016/0167-8140(93)90253-5