title: Development of a variable-radius pinhole SPECT system with a portable gamma camera.
abstract: OBJECTIVE
  To develop a small-animal SPECT system using a low cost commercial portable gamma camera equipped with a pinhole collimator, a continuous scintillation crystal and a position-sensitive photomultiplier tube.
  
  
  METHODS
  The gamma camera was attached to a variable radius system, which enabled us to optimize sensitivity and resolution by adjusting the radius of rotation to the size of the object. To investigate the capability of the SPECT system for small animal imaging, the dependence of resolution and calibration parameters on radius was assessed and acquisitions of small phantoms and mice were carried out.
  
  
  RESULTS
  Resolution values, ranging from 1.0mm for a radius of 21.4mm and 1.4mm for a radius of 37.2mm were obtained, thereby justifying the interest of a variable radius SPECT system.
  
  
  CONCLUSIONS
  The image quality of phantoms and animals were satisfactory, thus confirming the usefulness of the system for small animal SPECT imaging.
authors.affiliation: Unitat de Biofísica, Facultat de Medicina, Universitat de Barcelona, Spain. fpino@iconcologia.net
authors.forename: F
authors.initials: F
authors.lastname: Pino
authors.forename: N
authors.initials: N
authors.lastname: Roé
authors.forename: A
authors.initials: A
authors.lastname: Orero
authors.forename: C
authors.initials: C
authors.lastname: Falcón
authors.forename: S
authors.initials: S
authors.lastname: Rojas
authors.forename: J M
authors.initials: JM
authors.lastname: Benlloch
authors.forename: D
authors.initials: D
authors.lastname: Ros
authors.forename: J
authors.initials: J
authors.lastname: Pavía
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging; D002138:Calibration; D004867:Equipment Design; D015902:Gamma Cameras; D007091:Image Processing, Computer-Assisted; D008168:Lung / Q000000981:diagnostic imaging; D051379:Mice; D019047:Phantoms, Imaging; D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation* / Q000662:veterinary
chemical_list: D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; D019690:Technetium Tc 99m Exametazime