Linked Life Data

8703325

Source:http://linkedlifedata.com/resource/pubmed/id/8703325

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1996-9-12
pubmed:abstractText
The purpose of this study is to evaluate the magnitude of the error in dose delivery caused by the use of open beam depth dose data in dosimetry calculations for wedged photon beams. Isodose plans were calculated for treatments given in a 3-field isocentric prostate or rectal setup using an open AP beam with two lateral wedged beams. The dose distributions were first calculated using open beam depth dose data for all three fields. Next, the open beam data was used only for the AP field and true wedged beam depth dose data was substituted for the two lateral wedged fields. The magnitude of the depth dose variations for wedged vs open beams depends on the nominal beam energy, the wedge angle, and the depth of measurement. Consequently, isodose distributions calculated for wedged fields were found to be different when true wedged beam depth dose data was used instead of open beam data as is commonly done. Monitor unit calculations using a field size specific wedge factor show that dose delivery errors up to 4% can result from the use of open beam depth dose data in wedged beam dose distribution calculations for a 6-MV photon beam. Accurate treatment planning for wedged fields requires the use of wedged beam depth dose data specific to each wedge. Simply using open beam depth dose data in dose calculations for wedged beams will result in dose delivery errors, the magnitude of which depends on the combination of wedge angle, field size, and nominal beam energy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0958-3947
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
281-5
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Evaluation of dose delivery based on a comparison of dosimetry calculations using open beam and wedged beam depth dose data.
pubmed:affiliation
Dept. of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
pubmed:publicationType
Journal Article, Comparative Study