Linked Life Data

11818002

Source:http://linkedlifedata.com/resource/pubmed/id/11818002

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-1-30
pubmed:abstractText
An extensive set of measured data was developed for the purpose of verifying the accuracy of a photon dose-calculation algorithm. Dose distributions from a linear accelerator were measured using an ion chamber in a water phantom and thermoluminescent dosimeters in a heterogeneous anthropomorphic phantom. Test cases included square fields, rectangular fields, fields having different source-to-surface distances, wedged fields, irregular fields, obliquely incident fields, asymmetrically collimated fields with wedges, multileaf collimator-shaped fields, and two heterogeneous density cases. The data set was used to validate the photon dose-calculation algorithm in a commercial radiation treatment planning system. The treatment planning system calculated photon doses to within the American Association of Physicists in Medicine (AAPM) Task Group 53 (TG-53) criteria for 99% of points in the buildup region, 90% of points in the inner region, 88% of points in the outer region, and 93% of points in the penumbra. For the heterogeneous phantoms, calculations agreed with actual measurements to within +/-3%. The monitor unit tests revealed that the 18-MV open square fields, oblique incidence, oblique incidence with wedge, and mantle field test cases did not meet the TG-53 criteria but were within +/-2.5% of measurements. It was concluded that (i) the photon dose calculation algorithm used by the treatment planning system did not meet the TG-53 criteria 100% of the time; (ii) some of the TG-53 criteria may need to be modified, and (iii) the generally stated goal of accuracy in dose delivery of within 5% cannot be met in all situations using this beam model in the treatment planning system.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1526-9914
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26-45
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Verification of the accuracy of a photon dose-calculation algorithm.
pubmed:affiliation
Department of Radiation Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA. kagifford@mail.mdanderson.org
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't