In Vivo Dosimetry using Plastic Scintillation Detectors for External Beam Radiation Therapy

 
 
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3.5 Conclusion 
We have found that PSDs built with BCF-60 or BCF-12 scintillating fiber exhibit non-
negligible temperature dependence, with BCF-60 PSDs exhibiting greater temperature 
dependence than BCF-12 PSDs. For BCF-60 PSDs calibrated at room temperature, the 
dependence is on the order of 1% near room temperature and on the order of 10% at 
human body temperature. The exact mechanism of this temperature dependence is not 
known, but the wavelength shifting fluors and temperature-dependent transmission 
through cyanoacrylate appear to be at least partially responsible. We have suggested that 
a temperature-specific correction factors derived by characterizing the temperature 
dependence may be sufficient to account for this effect, although further research is 
required to validate this assertion. Alternatively, temperature-specific calibrations would 
account for the effect. In addition, carefully selecting the scintillator and optical coupling 
used in new PSDs may reduce the temperature dependence. Further research is needed to 
determine the optimal materials to use in a PSD to reduce or eliminate the temperature 
dependence.
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CHAPTER 4 
 
INTERNAL IN VIVO DOSIMETRY FOR PROSTATE INTENSITY 
MODULATED RADIATION THERAPY 
 
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This chapter is based on material published by the author of this dissertation in Physics 
in Medicine and Biology in 2014:[Wootton LS, Kudchadker RJ, Lee AK, and Beddar AS 
2014 Real-time in vivo rectal wall dosimetry using plastic scintillation detectors for 
patients with prostate cancer. Phys. Med. Biol. 58 2955-67]. It is reproduced here with 
permission of IOP Publishing. Wording in the introduction and discussion has been 
modified to conform to the overall style of this dissertation.