Abstract:
:The characteristics of an Elekta Precise treatment machine with a gating interface were investigated. Three detectors were used: a Farmer ionization chamber, a MatriXX ionization chamber array and an in-house, single pulse-measurement ionization chamber (IVC). Measurements were made of dosimetric accuracy, flatness and symmetry characteristics and duty cycle for a range of beam-on times and gating periods. Results were compared with a standard ungated delivery as a reference. For all beam-on times, down to 0.5 s, dosimetric differences were below +/-1% and flatness and symmetry parameter variations were below +/-1.5%. For the shorter beam-on times the in-house detector deviated from the other two detectors, suggesting that this device should be used in conjunction with other detectors for absolute dosimetry purposes. However, it was found to be useful for studying gated beam characteristics pulse by pulse.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Evans PM,Symonds-Tayler JR,Colgan R,Hugo GD,Letts N,Sandin Cdoi
10.1088/0031-9155/55/8/N02subject
Has Abstractpub_date
2010-04-21 00:00:00pages
N201-10issue
8eissn
0031-9155issn
1361-6560pii
S0031-9155(10)39881-2journal_volume
55pub_type
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