title: Comparison of gamma (Anger) camera systems in terms of detective quantum efficiency using Monte Carlo simulation.
abstract: OBJECTIVE
  The aim of the present study was to perform an extensive evaluation of available gamma camera systems in terms of their detective quantum efficiency (DQE) and determine their dependency on relevant parameters such as collimator type, imaging depth, and energy window using the Monte Carlo technique.
  
  
  METHODS
  The modulation transfer function was determined from a simulated (99m)Tc point source and was combined with the system sensitivity and photon yield to obtain the DQE of the system. The simulations were performed for different imaging depths in a water phantom for 13 gamma camera systems from four manufacturers.
  
  
  RESULTS
  Except at very low spatial frequencies, the highest DQE values were found with a lower energy window threshold of around 130 keV for all systems. The height and shape of the DQE curves were affected by the collimator design and the intrinsic properties of the gamma camera systems. High-sensitivity collimators gave the highest DQE at low spatial frequencies, whereas the high-resolution and ultrahigh-resolution collimators showed higher DQE values at higher frequencies. The intrinsic resolution of the system mainly affected the DQE curve at superficial depths.
  
  
  CONCLUSIONS
  The results indicate that the manufacturers have succeeded differently in their attempts to design a system constituting an optimal compromise between sensitivity and spatial resolution.
authors.affiliation: aDepartment of Medical Physics, Karlstad Hospital, Karlstad bDepartment of Radiation Physics, Institute of Clinical Sciences, the Sahlgrenska Academy at University of Gothenburg cDepartment of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg dDepartment of Natural Science and Biomedicine, School of Health Sciences, Jönköping University eHospital Physics, Department of Oncology, County Hospital Ryhov, Jönköping, Sweden.
authors.forename: Ida
authors.initials: I
authors.lastname: Eriksson
authors.forename: Sven-Åke
authors.initials: SÅ
authors.lastname: Starck
authors.forename: Magnus
authors.initials: M
authors.lastname: Båth
mesh_terms: D015902:Gamma Cameras; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D013667:Technetium; D014867:Water
chemical_list: D014867:Water; D013667:Technetium