Recent developments with a prototype fan-beam optical CT scanner

7th International Conference on 3D Radiation Dosimetry

Campbell, W.G.^1 ; Jirasek, A.^1 ; Wells, D.^2

Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada^1

BC Cancer Agency, Vancouver Island Centre, Victoria, BC, Canada^2

关键词: Beam intensity;    Cooling technique;    Data corruption;    Detector arrays;    Gel dosimeter;    Normoxic polymer gel;    Optical computed tomography;    Registration techniques;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/444/1/012066/pdf
DOI  :  10.1088/1742-6596/444/1/012066

来源: IOP

【 摘 要 】

The latest design of a prototype fan-beam optical computed tomography scanner is presented. A new beam creation system consists of a 635 nm laser diode module with variable, DC voltage-controlled beam intensity. A change in scanner alignment allows for the elimination of ring artefacts caused by data corruption that is spaced symmetrically across the detector array. These artefacts, as well as a pair of streaking artefacts caused by flask seams, are removed in sinogram space. A flask registration technique has been developed that allows for accurate, reproducible dosimeter placement. Protocol investigations with gel dosimeters have indicated the importance of: i) proper cooling techniques during gel manufacture, and ii) scanning the dosimeter while it is at room temperature. Latest reconstructions of a normoxic polymer gel dosimeter are presented as an indicator of current system performance.