Investigation of radiation sensitive normoxic polymer gels for radiotherapy dosimetry

摘要: The overall objective of this study was to develop and characterise new normoxic polymer gel formulations for evaluation complex 3-D treatment volumes application in radiotherapy dosimetry. Throughout thesis, the essential characteristics gels have been extensively investigated. Studies were performed on chemical components MAGIC an improved formulation proposed. Various anti-oxidants studied different versions with fewer chemicals developed named MAGAS MAGAT dosimeters. ascorbic acid anti-oxidant found a slow oxygen scavenging rate therefore delay period between manufacture irradiation necessary before became radiation sensitive. Vacuum pumping solution remove dissolved shown initially increase R2-dose response sensitivity dosimeter, reducing time irradiation. measurement depth dose showed that has potential as clinical dosimetry tool. radiological properties MAGIC, Due their high gelatine monomer concentration, differences water observed cross-section ratios attenuation, energy absorption collision stopping power coefficient through therapeutic range. It determined when using developing most important consideration equivalence are mass relative electron densities. A preliminary hypoxic PAG dosimeter combined tetrakis (hydroxymethyl) phosphonium chloride form PAGAT gel. compared favourably previous studies An extensive subsequently undertaken which investigated number characteristics. dosimetry, significantly reduced manufacturing procedure dosimeter. attenuation feasibility x-ray computerised tomography (CT) technique gels. CT tool measuring investigation diagnostic Normoxic use specialised index (CTDI) acceptance testing quality assurance scanners radiology. These findings provide significant contribution toward development successful implementation radiotherapy.