Abstract:
:Various forms of GAFChromic film have been used for several years as radiographic media for measuring dose distributions of brachytherapy sources and small radiation fields. Upon irradiation the film changes colour and darkens with time post-irradiation. The darkening is most rapid in the first 24 h, and it has been suggested that for accurate dosimetry a waiting period of 24 h should occur before any optical density (OD) measurements are taken. A more rapid colour stabilization (RCS) procedure has been developed and is evaluated. The procedure consists of heating the film post-irradiation for a period of 2 h at 45 degrees C. The RCS procedure is compared with a control group and the dose response is tested for linearity, stability and reproducibility using two densitometers with light sources at different wavelengths (632.8 nm and 671 nm). The rise in net optical density (NOD) for the period 3-168 h is less than 3% for the RCS group as compared with 12% for the controls. In the first 24 h, the increase in NOD for the RCS samples is less than 0.5%, as opposed to 6% for the control group.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Reinstein LE,Gluckman GR,Meek AGdoi
10.1088/0031-9155/43/10/001subject
Has Abstractpub_date
1998-10-01 00:00:00pages
2703-8issue
10eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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