title: Quantitation of myocardial blood flow and myocardial flow reserve with 99mTc-sestamibi dynamic SPECT/CT to enhance detection of coronary artery disease.
abstract: OBJECTIVE
  Conventional dual-head single photon emission computed tomography (SPECT)/CT systems capable of fast dynamic SPECT (DySPECT) imaging have a potential for flow quantitation. This study introduced a new method to quantify myocardial blood flow (MBF) and myocardial flow reserve (MFR) with DySPECT scan and evaluated the diagnostic performance of detecting coronary artery disease (CAD) compared with perfusion using invasive coronary angiography (CAG) as the reference standard.
  
  
  METHODS
  This study included 21 patients with suspected or known CAD who had received DySPECT, ECG-gated SPECT (GSPECT), and CAG (13 with ≥ 50% stenosis in any vessel; non-CAD group: 8 with patent arteries or < 50% stenosis). DySPECT and GSPECT scans were performed on a widely used dual-head SPECT/CT scanner. The DySPECT imaging protocol utilized 12-min multiple back-and-forth gantry rotations during injections of (99m)Tc-sestamibi (MIBI) tracer at rest or dipyridamole-stress stages. DySPECT images were reconstructed with full physical corrections and converted to the physical unit of becquerels per milliliter. Stress MBF (SMBF), rest MBF (RMBF), and MFR were quantified by a one-tissue compartment flow model using time-activity curves derived from DySPECT images. Perfusion images were processed for GSPECT scan and interpreted to obtain summed stress score (SSS) and summed difference score (SDS). Receiver-operating characteristic (ROC) analyses were conducted to evaluate the diagnostic performance of flow and perfusion.
  
  
  RESULTS
  Using the criteria of ≥ 50% stenosis as positive CAD, areas under the ROC curve (AUCs) of flow assessment were overall significantly greater than those of perfusion. For patient-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.91 ± 0.07, 0.86 ± 0.09, 0.64 ± 0.12, and 0.59 ± 0.13. For vessel-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.81 ± 0.05, 0.76 ± 0.06, 0.62 ± 0.07, and 0.56 ± 0.08, respectively.
  
  
  CONCLUSIONS
  The preliminary data suggest that MBF quantitation with a conventional SPECT/CT system and the flow quantitation method is a clinically effective approach to enhance CAD detection.
authors.affiliation: Nuclear Science and Engineering Institute, University of Missouri-Columbia, Columbia, MO, USA.
authors.forename: Bailing
authors.initials: B
authors.lastname: Hsu
authors.forename: Fu-Chung
authors.initials: FC
authors.lastname: Chen
authors.forename: Tao-Cheng
authors.initials: TC
authors.lastname: Wu
authors.forename: Wen-Sheng
authors.initials: WS
authors.lastname: Huang
authors.forename: Po-Nien
authors.initials: PN
authors.lastname: Hou
authors.forename: Chien-Cheng
authors.initials: CC
authors.lastname: Chen
authors.forename: Guang-Uei
authors.initials: GU
authors.lastname: Hung
mesh_terms: D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi
chemical_list: D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi