title: SPECT myocardial blood flow quantitation toward clinical use: a comparative study with13N-Ammonia PET myocardial blood flow quantitation.
abstract: OBJECTIVE
  The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of99mTc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with13N-Ammonia (NH3) position emission tomography (PET) on the same cohorts.
  
  
  BACKGROUND
  Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations.
  
  
  METHODS
  Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach.
  
  
  RESULTS
  The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R2: MBF = 0.92, MFR = 0.78; regional R2: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06 , ΔMFR = -0.02 - 0.22).
  
  
  CONCLUSIONS
  Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected.
authors: Nuclear Science and Engineering Institute, University of Missouri-Columbia, Columbia, Missouri, USA.
authors: Bailing
authors: B
authors: Hsu
authors: Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors: Lien-Hsin
authors: LH
authors: Hu
authors: Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors: Bang-Hung
authors: BH
authors: Yang
authors: Division of Cardiology, Shin Kong Wu-Ho Su Memorial Hospital, Taipei, Taiwan.
authors: Lung-Ching
authors: LC
authors: Chen
authors: Department of Nuclear Medicine, Shin Kong Wu-Ho Su Memorial Hospital, Taipei, Taiwan.
authors: Yen-Kung
authors: YK
authors: Chen
authors: Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors: Chien-Hsin
authors: CH
authors: Ting
authors: Department of Nuclear Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua, Taiwan.
authors: Guang-Uei
authors: GU
authors: Hung
authors: Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. wshuang01@gmail.com.
authors: Wen-Sheng
authors: WS
authors: Huang
authors: Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan. dcwu@vghtpe.tw.
authors: Tao-Cheng
authors: TC
authors: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000641:Ammonia; D001783:Blood Flow Velocity; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003326:Coronary Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods; D009590:Nitrogen Radioisotopes; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D009590:Nitrogen Radioisotopes; D019275:Radiopharmaceuticals; D000641:Ammonia; D017256:Technetium Tc 99m Sestamibi
keywords: 13N-Ammonia PET; 99mTc-Sestamibi dynamic SPECT; coronary artery disease; myocardial blood flow quantitation