title: Impact of attenuation correction and gated acquisition in SPECT myocardial perfusion imaging: results of the multicentre SPAG (SPECT Attenuation Correction vs Gated) study.
abstract: OBJECTIVE
  In clinical myocardial single photon emission computed tomography (SPECT), attenuation artefacts may cause a loss of specificity in the identification of diseased vessels that can be corrected by means of gated SPECT (GSPECT) acquisition or CT attenuation correction (AC). The purpose of this multicentre study was to assess the impact of GSPECT and AC on the diagnostic performance of myocardial scintigraphy, according to patient's sex, body mass index (BMI) and site of coronary artery disease (CAD).
  
  
  METHODS
  We studied a group of 104 patients who underwent coronary angiography within 1 month before or after the SPECT study. Patients with a BMI>27 were considered "overweight". Attenuation-corrected and standard GSPECT early images were randomly interpreted by three readers blinded to the clinical data.
  
  
  RESULTS
  In the whole group, GSPECT and AC showed a diagnostic accuracy of 86.5% (sensitivity 82%, specificity 93%) and 77% (sensitivity 75.4%, specificity 81.4%), respectively (p<0.05). In women, when anterior ischaemia was matched with CAD, AC failed to show any increase in specificity (AC 63.6% vs GSPECT 63.6%) with evident loss of sensitivity (AC 72.7% vs GSPECT 90.9%). AC significantly improved SPECT specificity in the identification of right CAD in overweight men (AC 100% vs GSPECT 66.7%, p<0.05).
  
  
  CONCLUSIONS
  AC improved specificity in the evaluation of right CAD in overweight men. In the other evaluable subgroups specificity was not significantly affected while sensitivity was frequently reduced.
authors.affiliation: Nuclear Medicine, Fondazione CNR-Regione Toscana G. Monasterio, Via G. Moruzzi 1, 56124, Pisa, Italy. dario.genovesi@ifc.cnr.it
authors.forename: Dario
authors.initials: D
authors.lastname: Genovesi
authors.forename: Assuero
authors.initials: A
authors.lastname: Giorgetti
authors.forename: Alessia
authors.initials: A
authors.lastname: Gimelli
authors.forename: Annette
authors.initials: A
authors.lastname: Kusch
authors.forename: Irene
authors.initials: I
authors.lastname: D'Aragona Tagliavia
authors.forename: Mirta
authors.initials: M
authors.lastname: Casagranda
authors.forename: Giorgio
authors.initials: G
authors.lastname: Cannizzaro
authors.forename: Raffaele
authors.initials: R
authors.lastname: Giubbini
authors.forename: Francesco
authors.initials: F
authors.lastname: Bertagna
authors.forename: Giorgio
authors.initials: G
authors.lastname: Fagioli
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Rossi
authors.forename: Annadina
authors.initials: A
authors.lastname: Romeo
authors.forename: Pietro
authors.initials: P
authors.lastname: Bertolaccini
authors.forename: Rita
authors.initials: R
authors.lastname: Bonini
authors.forename: Paolo
authors.initials: P
authors.lastname: Marzullo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D015992:Body Mass Index; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D012737:Sex Factors; D014057:Tomography, X-Ray Computed