Novel optical fibre sensors and their applications in radiotherapy

Majed Alharbi, Michael Martyn, Lingxia Chen, Sean Gillespie, Peter Woulfe, Sinead O'Keeffe, Mark Foley

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

The aim of this study was to investigate the over-response of an inorganic optical fibre sensor (OFS) when measuring percentage depth dose curves (PDDs) with respect to an ion chamber by means of physical measurements and Monte Carlo (MC) simulations. The sensor was constructed by filling a cavity (700 μm diameter and 7 mm deep), which was made in a PMMA (polymethyl methacrylate) plastic optical fibre, with an inorganic scintillating material: Terbium doped gadolinium oxysulphide (Gd2O2S:Tb). The MC software packages BEAMnrc and DOSXYZnrc were used to develop a MC model of an Elekta Versa HD linear accelerator (linac), which was then used to simulate the Gd2O2S:Tb scintillator. The results of the PDD measurements showed a depth dependence of the OFS, however the percentage differences between the ion chamber and the OFS measurements showed that as the radiation field size decreases, the difference between the two measurements decreases from 16.5% to 5.1% for 10x10 cm2 and 2x2 cm2, respectively. The MC simulation of the sensor showed a good agreement compared to physical measurements at shallow depth in the phantom; however, discrepancies were observed at depth, which was less pronounced for 4x4 cm2 than for 10x10 cm2. The results of this study indicate that including Cerenkov radiation measurements is essential to accurately quantify the overresponse and the higher discrepancy between the measured and simulated PDD profiles of the OFS.

Original languageEnglish
Title of host publicationOptical Sensing and Detection V
EditorsFrancis Berghmans, Anna G. Mignani
PublisherSPIE
ISBN (Electronic)9781510618862
DOIs
Publication statusPublished - 2018
EventOptical Sensing and Detection V 2018 - Strasbourg, France
Duration: 23 Apr 201826 Apr 2018

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume10680
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X

Conference

ConferenceOptical Sensing and Detection V 2018
Country/TerritoryFrance
CityStrasbourg
Period23/04/1826/04/18

Keywords

  • Inorganic Scintillator
  • Monte Carlo
  • Optical Fibre Sensors
  • Percentage Depth Dose
  • Radiation Therapy

Fingerprint

Dive into the research topics of 'Novel optical fibre sensors and their applications in radiotherapy'. Together they form a unique fingerprint.

Cite this