title: Myocardium: dynamic versus single-shot CT perfusion imaging.
abstract: OBJECTIVE
  To determine the diagnostic accuracy of dynamic computed tomographic (CT) perfusion imaging of the myocardium for the detection of hemodynamically relevant coronary artery stenosis compared with the accuracy of coronary angiography and fractional flow reserve (FFR) measurement.
  
  
  METHODS
  This study was approved by the institutional review board and the Federal Radiation Safety Council (Bundesamt für Strahlenschutz). All patients provided written informed consent. Thirty-two consecutive patients in adenosine stress conditions underwent dynamic CT perfusion imaging (14 consecutive data sets) performed by using a 256-section scanner with an 8-cm detector and without table movement. Time to peak, area under the curve, upslope, and peak enhancement were determined after calculation of time-attenuation curves. In addition, myocardial blood flow (MBF) was determined quantitatively. Results were compared with those of coronary angiography and FFR measurement by using a receiver operating characteristic (ROC) analysis. In addition, threshold values based on the Youden index and sensitivity and specificity were calculated.
  
  
  RESULTS
  Area under the ROC curve, sensitivity, and specificity, respectively, were 0.67, 41.4% (95% confidence interval [CI]: 23.5%, 61.1%), and 86.6% (95% CI: 76.0%, 93.7%) for time to peak; 0.74, 58.6% (95% CI: 38.9%, 76.5%), and 83.6% (95% CI: 72.5%, 91.5%) for area under the curve; 0.87, 82.8% (95% CI: 64.2%, 94.1%), and 88.1% (95% CI: 77.8%, 94.7%) for upslope; 0.83, 82.8% (95% CI: 64.2%, 94.1%), and 89.6% (95% CI: 79.6%, 95.7%) for peak enhancement; and 0.86, 75.9% (95% CI: 56.5%, 89.7%), and 100% (95% CI: 94.6%, 100%) for MBF. The thresholds determined by using the Youden index were 148.5 HU · sec for area under the curve, 12 seconds for time to peak, 2.5 HU/sec for upslope, 34 HU for peak enhancement, and 1.64 mL/g/min for MBF.
  
  
  CONCLUSIONS
  The semiquantitative parameters upslope and peak enhancement and the quantitative parameter MBF showed similar high diagnostic accuracy.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13121441/-/DC1.
authors.affiliation: Institute for Diagnostic and Interventional Radiology, Klinikum rechts der Isar der Technischen, Universität München, Ismaninger Str. 22, 81675 Munich, Germany; Clinic for Cardiology and Internal Intensive Care Medicine, Klinikum Bogenhausen, Munich, Germany.
authors.forename: Armin M
authors.initials: AM
authors.lastname: Huber
authors.forename: Vivian
authors.initials: V
authors.lastname: Leber
authors.forename: Bettina M
authors.initials: BM
authors.lastname: Gramer
authors.forename: Daniela
authors.initials: D
authors.lastname: Muenzel
authors.forename: Alexander
authors.initials: A
authors.lastname: Leber
authors.forename: Johannes
authors.initials: J
authors.lastname: Rieber
authors.forename: Martin
authors.initials: M
authors.lastname: Schmidt
authors.forename: Mani
authors.initials: M
authors.lastname: Vembar
authors.forename: Ellen
authors.initials: E
authors.lastname: Hoffmann
authors.forename: Ernst
authors.initials: E
authors.lastname: Rummeny
mesh_terms: D000368:Aged; D015897:Comorbidity; D003287:Contrast Media; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D005080:Exercise Test; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D007479:Iopamidol / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol