Iodine contrast nPAG for radiologically visible target region in deformable dosimeters. (August 2019)

• Record Type: Journal Article
• Authors: Watson, C J; Yeo, A U; Supple, J R; Geso, M; Kron, T; Franich, R D
• Is Part Of: Journal of physics. Volume 1305(2019)
• Publication Date: 2019-08
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/1305/1/012048
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: The utility of gel dosimeters is sought to be improved upon in this study which proposes a target region of different X-ray CT contrast that is dose sensitive. The changes in the physico-chemical makeup of nPAG caused by the addition of the X-ray imaging Iodine based contrast agent Isovue are explored. The impact of this change on dose measurements is also discussed. The increase in HU as it correlates with increasing Isovue concentration is detailed, along with the dosimetric changes that occur, namely the steepness of the dose response curve and general shape of the percentage depth dose curve. It is noted that diffusion of Isovue from one gel region to another has significant dosimetric impact and the experimental method was constructed and conducted with this in mind. Further refinement and optimisation of the Isovue nPAG formulation will lead to a target region dosimeter that can be contoured on X-ray CT and used in the improvement of planning protocols, especially in cases that involve motion and deformation of target volumes.