An experimental study of the dose response of polymer gel dosimeters imaged with x-ray computed tomography

• Published in: Physics in medicine & biology Vol. 46; no. 11; pp. 2939 - 2951
• Main Authors: Trapp, J V, Bäck, S Å J, Lepage, M, Michael, G, Baldock, C
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.11.2001; Institute of Physics
• Subjects: Acrylamide - chemistry; Acrylamides - chemistry; Applied radiobiology (equipment, dosimetry...); Biological and medical sciences; Biological effects of radiation; Clinical Medicine; Dose-Response Relationship, Drug; Dose-Response Relationship, Radiation; Fundamental and applied biological sciences. Psychology; Gelatin - chemistry; Klinisk medicin; Medical and Health Sciences; Medicin och hälsovetenskap; Phantoms, Imaging; Polymers - chemistry; Radiologi och bildbehandling; Radiology, Nuclear Medicine and Medical Imaging; Radiometry - instrumentation; Radiometry - methods; Tissues, organs and organisms biophysics; Tomography, X-Ray Computed - methods; Dose repartition; Correlation; Radiodiagnosis; Polymer; Experimental study; X ray irradiation; Dose activity relation; Sensitivity; Attenuation coefficient; Chemical dosimeter; Medical imagery; Chemical composition; Computerized axial tomography; Dosimetry; Freeze
• ISSN: 0031-9155; 1361-6560; 1361-6560
• DOI: 10.1088/0031-9155/46/11/312

Changes in the linear attenuation coefficient of polymer gel dosimeters post-irradiation enable the imaging of dose distributions by x-ray computed tomography (CT). Various compositions of polymer gel dosimeters manufactured from acrylamide (AA), and N,N'-methylene-bis-acrylamide (BIS) comonomers and gelatin or agarose gelling agents were investigated. This work shows that increasing the comonomer concentration increases the CT-dose sensitivity of the polymer gel dosimeter. This can be further increased by replacing gelatin with agarose. Varying the gelatin concentration however does not significantly change the CT-dose sensitivity. Among the compositions studied, dose resolution (D(delta)95%) was found to be optimal for polymer gel dosimeters comprising 5% gelatin, 3% AA, 3% BIS and 89% water.