title: Absolute myocardial flow quantification with (82)Rb PET/CT: comparison of different software packages and methods.
abstract: OBJECTIVE
  In clinical cardiac (82)Rb PET, globally impaired coronary flow reserve (CFR) is a relevant marker for predicting short-term cardiovascular events. However, there are limited data on the impact of different software and methods for estimation of myocardial blood flow (MBF) and CFR. Our objective was to compare quantitative results obtained from previously validated software tools.
  
  
  METHODS
  We retrospectively analyzed cardiac (82)Rb PET/CT data from 25 subjects (group 1, 62 ± 11 years) with low-to-intermediate probability of coronary artery disease (CAD) and 26 patients (group 2, 57 ± 10 years; P=0.07) with known CAD. Resting and vasodilator-stress MBF and CFR were derived using three software applications: (1) Corridor4DM (4DM) based on factor analysis (FA) and kinetic modeling, (2) 4DM based on region-of-interest (ROI) and kinetic modeling, (3) MunichHeart (MH), which uses a simplified ROI-based retention model approach, and (4) FlowQuant (FQ) based on ROI and compartmental modeling with constant distribution volume.
  
  
  RESULTS
  Resting and stress MBF values (in milliliters per minute per gram) derived using the different methods were significantly different: using 4DM-FA, 4DM-ROI, FQ, and MH resting MBF values were 1.47 ± 0.59, 1.16 ± 0.51, 0.91 ± 0.39, and 0.90 ± 0.44, respectively (P<0.001), and stress MBF values were 3.05 ± 1.66, 2.26 ± 1.01, 1.90 ± 0.82, and 1.83 ± 0.81, respectively (P<0.001). However, there were no statistically significant differences among the CFR values (2.15 ± 1.08, 2.05 ± 0.83, 2.23 ± 0.89, and 2.21 ± 0.90, respectively; P=0.17). Regional MBF and CFR according to vascular territories showed similar results. Linear correlation coefficient for global CFR varied between 0.71 (MH vs. 4DM-ROI) and 0.90 (FQ vs. 4DM-ROI). Using a cut-off value of 2.0 for abnormal CFR, the agreement among the software programs ranged between 76 % (MH vs. FQ) and 90 % (FQ vs. 4DM-ROI). Interobserver agreement was in general excellent with all software packages.
  
  
  CONCLUSIONS
  Quantitative assessment of resting and stress MBF with (82)Rb PET is dependent on the software and methods used, whereas CFR appears to be more comparable. Follow-up and treatment assessment should be done with the same software and method.
authors: Divisions of Nuclear Medicine, Johns Hopkins Medical Institutions, Department of Radiology, 601 N. Caroline Street, Suite 3223, Baltimore, MD, 21287, USA, atahari1@jhmi.edu.
authors: Abdel K
authors: AK
authors: Tahari
authors: Andy
authors: A
authors: Lee
authors: Mahadevan
authors: M
authors: Rajaram
authors: Kenji
authors: K
authors: Fukushima
authors: Martin A
authors: MA
authors: Lodge
authors: Benjamin C
authors: BC
authors: Lee
authors: Edward P
authors: EP
authors: Ficaro
authors: Stephan
authors: S
authors: Nekolla
authors: Ran
authors: R
authors: Klein
authors: Robert A
authors: RA
authors: deKemp
authors: Richard L
authors: RL
authors: Wahl
authors: Frank M
authors: FM
authors: Bengel
authors: Paco E
authors: PE
authors: Bravo
mesh_terms: D003326:Coronary Circulation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D055414:Myocardial Perfusion Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D012189:Retrospective Studies; D012414:Rubidium Radioisotopes; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D012414:Rubidium Radioisotopes
references: J Am Coll Cardiol. 2009 Jul 7;54(2):150-6
references: 19573732
references: J Nucl Cardiol. 2010 Aug;17(4):600-16
references: 20387135
references: J Am Coll Cardiol. 2011 Aug 9;58(7):740-8
references: 21816311
references: J Nucl Med. 2005 Aug;46(8):1264-71
references: 16085581
references: Eur J Nucl Med. 1998 Sep;25(9):1313-21
references: 9724382
references: Circulation. 2011 Nov 15;124(20):2215-24
references: 22007073
references: J Am Coll Cardiol. 2007 Mar 13;49(10):1052-8
references: 17349884
references: Int J Cardiol. 2013 Aug 10;167(3):1023-6
references: 22475847
references: Med Phys. 2010 Aug;37(8):3995-4010
references: 20879561
references: Eur J Nucl Med Mol Imaging. 2012 Aug;39(8):1233-9
references: 22648514
references: J Nucl Med. 2009 Feb;50(2):214-9
references: 19164219
references: J Am Coll Cardiol. 2006 Sep 5;48(5):1029-39
references: 16949498
references: Semin Nucl Med. 2005 Jan;35(1):17-36
references: 15645392
references: Circulation. 2007 Mar 20;115(11):1464-80
references: 17372188
references: J Nucl Cardiol. 2008 Nov-Dec;15(6):745-53
references: 18984449
references: Eur J Nucl Med Mol Imaging. 2007 Nov;34(11):1765-74
references: 17619189
references: Circ Res. 1992 Mar;70(3):496-507
references: 1537087
references: J Nucl Med. 1996 Oct;37(10):1701-12
references: 8862316
references: J Nucl Cardiol. 2010 Oct;17(5):941-73
references: 20552312
references: J Nucl Med. 2013 Jan;54(1):50-4
references: 23090213
references: J Am Coll Cardiol. 2011 Aug 9;58(7):749-51
references: 21816312
references: J Am Coll Cardiol. 2009 Jun 30;54(1):1-15
references: 19555834
references: Eur J Nucl Med Mol Imaging. 2009 Apr;36(4):576-86
references: 18985343
references: J Nucl Cardiol. 2006 Jan-Feb;13(1):24-33
references: 16464714
references: J Nucl Med. 2011 May;52(5):726-32
references: 21498538
references: J Nucl Med. 2012 Feb;53(2):171-81
references: 22228795
references: J Nucl Cardiol. 2010 Aug;17(4):555-70
references: 20596841
references: IEEE Trans Med Imaging. 2002 Mar;21(3):216-25
references: 11989846
references: J Nucl Med. 2009 Jul;50(7):1062-71
references: 19525467