Abstract：
:The purpose of this study was to measure skin dose using radiochromic film for two step-and-shoot IMRT fields and compare the results to the skin dose for a conventional open field. All exposures were made using a 6 MV photon beam produced by a Varian 21EX linear accelerator (Varian Medical Systems, CA, USA) equipped with a Millennium 120 leaf MLC. Three different field configurations were used, these were an open field, a step-and-shoot IMRT field and a clinical IMRT field. The mean ratio of the skin dose to dose at d(max) for an open 10 x 10 cm2 field at 100 cm SSD was 0.178 +/- 0.003. The step-and-shoot IMRT field consisted of 1 cm wide strips of decreasing intensity that were delivered using a step-and-shoot technique across a 10 x 10 cm2 field. The ratio of skin dose to dose at d(max) ranged from 0.180 to 0.257, with the low intensity steps having a higher relative skin dose compared to the high intensity steps. A model was derived that attributed these variations to the electron contamination from both the adjacent and more distant high intensity steps. The clinical field consisted of a 25 segment 9.8 x 10.0 cm2 beam arrangement. The ratio of skin dose to dose at d(max) for the clinical IMRT field ranged from 0.093 to 0.284. The results indicated that an IMRT field produced only minor changes in the relative skin dose, with variations potentially attributable to fluctuations in the electron contamination produced by neighbouring regions of different intensity. The use of an individual IMRT field does not significantly increase the skin dose above that of a conventional photon field.
journal_name
Australas Phys Eng Sci Medjournal_title
Australasian physical & engineering sciences in medicineauthors
Price S,Williams M,Butson M,Metcalfe Pdoi
10.1007/BF03178577subject
Has Abstractpub_date
2006-09-01 00:00:00pages
272-7issue
3eissn
0158-9938issn
1879-5447journal_volume
29pub_type
杂志文章abstract：:Thermoluminescence dosimetry (TLD) is a versatile tool for the assessment of dose from ionising radiation. The wide variety of TLD materials and their different physical forms allow the determination of different radiation qualities at dose levels from microGy to kGy. Major advantages of TL dosimeters are their small ...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
doi：
更新日期：1994-12-01 00:00:00
abstract：:Over 90% of craniopharyngeal brain tumors are cystic, which enables the injection of beta emitters such as phosphorus-32 (32P) radio-colloid into cysts for their treatment. The aim of this study was to evaluate the clinical and theoretical modelling of Bremsstrahlung radiation dose resulting from stereotactic radio-co...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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更新日期：2018-09-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
doi：10.1007/BF03178423
更新日期：2007-09-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:The Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) Radiation Oncology Specialty Group (ROSG) formed a series of working groups in 2011 to develop position papers for guidance of radiation oncology medical physics practice within the Australasian setting. These position papers are intend...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-013-0238-5
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-015-0363-4
更新日期：2015-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 指南,杂志文章
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更新日期：2004-03-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178283
更新日期：2001-03-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178723
更新日期：2005-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178780
更新日期：2003-09-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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更新日期：2008-03-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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更新日期：2010-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178603
更新日期：2008-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
doi：
更新日期：1996-06-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-017-0555-1
更新日期：2017-09-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type：
doi：10.1007/BF03178583
更新日期：2008-06-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-016-0452-z
更新日期：2016-06-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1998-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-014-0250-4
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-017-0558-y
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1991-06-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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journal_title：Australasian physical & engineering sciences in medicine
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章,评审
doi：
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1993-12-01 00:00:00
