Radiation doses used in radiation therapy are calculated during the course of treatment planning. Cross-validation of calculated dose versus received dose is performed mostly in-vitro and may not represent actual therapy doses. In vivo measurements are at best typically limited to a few surface points. Presently, dose is measured primarily with diodes, thermoluminescent or MOSFET dosimeters. Their outer sizes are in the range of 3 mm, which are unpractical for in vivo internal use, in particular for interstitial or intracavital brachytherapy. In addition, diode and MOSFET sensors are individually tethered to cables and are therefore inconvenient for making multiple point measurements. Feasibility of multiple point radiation dosimetry using luminescent optical fibers for in vivo dosimetry during radiation therapy is described that overcomes these difficulties. The spectral response of a candidate rare-earth doped optical fiber dosimetric probe is reported, having 0.5 rads/cm sensitivity. This sensor capability would enable continuous radiation monitoring of dose and dose rate during therapy at multiple locations along the sensor fiber.

Date Published: 13 February 2008
PDF: 5 pages
Proc. SPIE 6852, Optical Fibers and Sensors for Medical Diagnostics and Treatment Applications VIII, 68520L (13 February 2008); doi: 10.1117/12.784735

Published in SPIE Proceedings Vol. 6852:
Optical Fibers and Sensors for Medical Diagnostics and Treatment Applications VIII
Israel Gannot, Editor(s)