Linked Life Data

20808027

Source:http://linkedlifedata.com/resource/pubmed/id/20808027

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2010-9-2
pubmed:abstractText
High spatial resolution is desired for dosimetrical verification of patient plans for radiotherapy treatments employing scanned ion beams. This is provided by Gafchromic EBT film, the ancestor of currently available EBT2 films. In this contribution, dosimetric properties of EBT films were investigated. Measurements of depth response were performed for monoenergetic fields (250 MeV/u) for different ion fluences as well as for an energy-modulated spread-out Bragg peak of 5 x 5 x 5 cm(3) in 10 cm depth. The films were positioned perpendicular to the incoming carbon ion beams. The observed quenching of the response relative to the same dose of photons was quantified by the relative efficiency. In monenenergetic beams, a relative efficiency of about 0.73 was found in the plateau, 0.4 in the peak and 0.55 in the tail region. No dependence of the relative efficiency on the ion fluence was observed well beyond the clinically used levels. This gives a constant peak to plateau ratio, which is about 1.8 times lower than that for the delivered dose. In the spread-out Bragg peak, the relative efficiency was found to decrease from 0.64 to 0.54 toward the distal end. Thus when aiming for a prediction of the film response in mixed ion beams, the efficiency of the film has to be parametrized as a function of the ion type and energy over the whole ion spectrum. In addition, the relative water-equivalent range of EBT films was measured here to be 1.291 +/- 0.015.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1361-6560
pubmed:author
pubmed:issnType
Electronic
pubmed:day
21
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5557-67
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Dosimetric properties of Gafchromic(R) EBT films in medical carbon ion beams.
pubmed:affiliation
Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany. m.martisikova@dkfz.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't