title: Half-time myocardial perfusion SPECT imaging with attenuation and Monte Carlo-based scatter correction.
abstract: OBJECTIVE
  To test the potential of a new reconstruction algorithm with Monte Carlo-based scatter correction in half-time myocardial perfusion single-photon emission computed tomography (SPECT).
  
  
  METHODS
  The mathematical four-dimensional NURBS-based Cardiac-Torso phantom and the SIMIND Monte Carlo simulation package were used to simulate full-time and half-time SPECT projection data. The data were reconstructed using the standard ordered subset expectation maximization-based algorithm and the new Monte Carlo-based algorithm. Defect contrast, myocardium versus ventricle contrast and resolution were calculated. In addition to the simulation studies, full-time and half-time SPECT projection data of 30 patients were reconstructed with the standard and the new method. The patient data were qualitatively evaluated by four nuclear medicine experts on a scale from 1 (poor quality) to 5 (high quality).
  
  
  RESULTS
  The new reconstruction method with half-time data produced higher contrast and better resolution in the simulations and also achieved higher qualitative scores in the patient study than the standard reconstruction with full-time data.
  
  
  CONCLUSIONS
  Half-time myocardial perfusion imaging using the new reconstruction algorithm with Monte Carlo-based scatter correction produced images with superior quality when compared with full-time imaging with standard reconstruction.
authors.affiliation: Department of Radiation Therapy, Vaasa Central Hospital, Vaasa, Finland. tuija.kangasmaa@vshp.fi
authors.forename: Tuija S
authors.initials: TS
authors.lastname: Kangasmaa
authors.forename: Jyrki T
authors.initials: JT
authors.lastname: Kuikka
authors.forename: Esko J
authors.initials: EJ
authors.lastname: Vanninen
authors.forename: Hanna M
authors.initials: HM
authors.lastname: Mussalo
authors.forename: Tomi P
authors.initials: TP
authors.lastname: Laitinen
authors.forename: Antti O
authors.initials: AO
authors.lastname: Sohlberg
mesh_terms: D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D009010:Monte Carlo Method; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009206:Myocardium; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D010477:Perfusion; D019047:Phantoms, Imaging; D011859:Radiography; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; C078700:technetium tc-99m tetrofosmin