Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-2-24
pubmed:abstractText
When treating prostate cancer using high dose rate (HDR) brachytherapy, overdosing the rectal wall may lead to post-treatment rectal complications. An area of concern is related to how the rectal wall dose is calculated by treatment planning systems (TPSs). TPSs are used to calculate the dose delivered to the rectal wall, but they assume that the rectum is a water-equivalent homogeneous medium of infinite size and do not consider the effect that an air-filled "empty" rectal cavity would have on the dose absorbed along the rectal wall. The aim of this research is to quantify the effect that an air cavity has on the rectal wall dose, as its presence changes the backscatter conditions in the region. The MO Skin and RADFET dosimeters proved capable of measuring absolute dose with increasing distance from the HDR Ir-192 brachytherapy source. However, the anterior rectal wall doses measured by the MOSkin and RADFET in an empty rectal cavity were 14.7 +/- 0.2% and 13.7 +/- 0.6% lower than the dose measured in a homogeneous rectal phantom. Monte Carlo simulations corroborated the experimentally obtained results, reporting a -13.2 +/- 0.6% difference. The dose measured at the posterior wall of an empty rectal cavity was between 22% and 26% greater than the dose measured in a full rectal cavity. The heterogeneity of the rectal volume appears to have a significant effect on the rectal dose when compared to calculated rectal dose.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0094-2405
pubmed:author
pubmed:issnType
Print
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
224-32
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
The effect of rectal heterogeneity on wall dose in high dose rate brachytherapy.
pubmed:affiliation
Centre of Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2522, Australia.
pubmed:publicationType
Journal Article