Misalignments calibration in small-animal PET scanners based on rotating planar detectors and parallel-beam geometry Articles uri icon

publication date

  • November 2012

start page

  • 7493

end page

  • 7518

issue

  • 22

volume

  • 57

international standard serial number (ISSN)

  • 0031-9155

electronic international standard serial number (EISSN)

  • 1361-6560

abstract

  • Technological advances have improved the assembly process of PET detectors, resulting in quite small mechanical tolerances. However, in high-spatial-resolution systems, even submillimetric misalignments of the detectors may lead to a notable degradation of image resolution and artifacts. Therefore, the exact characterization of misalignments is critical for optimum reconstruction quality in such systems. This subject has been widely studied for CT and SPECT scanners based on cone beam geometry, but this is not the case for PET tomographs based on rotating planar detectors. The purpose of this work is to analyze misalignment effects in these systems and to propose a robust and easy-to-implement protocol for geometric characterization. The result of the proposed calibration method, which requires no more than a simple calibration phantom, can then be used to generate a correct 3D-sinogram from the acquired list mode data.

keywords

  • positron emission tomography (pet); non-ionizing radiation equipment and techniques; image quality; image analysis; medical physics