Evaluation of pinhole collimator materials for micron-resolution < i > ex-vivo < /i > SPECT.
Evaluation of pinhole collimator materials for micron-resolution <i>ex-vivo</i> SPECT.
Phys Med Biol. 2019 Apr 04;:
Authors: Nguyen MP, Goorden MC, Kamphuis C, Beekman FJ
Abstract
Pinhole collimation is widely recognized for offering superior resolution-sensitivity trade-off in SPECT imaging of small subjects. The newly developed EXIRAD-3D autoradiography technique (MILabs B.V.) based on a highly focusing multi-pinhole collimator achieves micron-resolution SPECT for cryo-cooled tissue samples. For such high resolutions, the choice of pinhole material may have a significant impact on images. Therefore, this paper aims to compare the performance of EXIRAD-3D with lead, tungsten, gold, and depleted uranium pinhole collimators designed such that they achieve equal sensitivities. Performance in terms of resolution is characterized for several radioisotopes, namely <sup>111</sup>In (171 keV and 245 keV), <sup>99m</sup>Tc (140 keV), <sup>201</sup>Tl (71 keV), and <sup>125</sup>I (27 keV). Using Monte Carlo simulation, point spread functions were simulated and their profiles as well as their full-width-at-half-maximum and full-width-at-tenth-maximum were determined and evaluated for different materials and isotopes. Additionally, reconstructed images of a Derenzo resolution phantom, validated with experimental data, wer...
Source: Physics in Medicine and Biology - Category: Physics Authors: Nguyen MP, Goorden MC, Kamphuis C, Beekman FJ Tags: Phys Med Biol Source Type: research