Effect of reduced photon count levels and choice of normal data on semi-automated image assessment in cardiac SPECT

  • Matthias Wetzl
  • James C. Sanders
  • Torsten Kuwert
  • Philipp Ritt
Original Article



The SMARTZOOM multifocal collimator from Siemens Healthcare was developed to improve the γ-photon sensitivity in myocardial perfusion imaging without truncating the field of view. As part of the IQ-SPECT package, it may be used to reduce radiopharmaceutical dose to patients, as well as acquisition time. The aim of this study was twofold: (1) to evaluate the influence of dose reduction in semi-automated MPI scoring, with focus on different strategies for the choice of normal data (count-matched, full-count), and (2) to evaluate the effect of dose reduction afforded by Siemens’ IQ-SPECT package.


50 patients underwent Tc-99m-sestamibi one-day stress/rest SPECT/CT. Multiple levels of count reduction were generated using binomial thinning. Using Corridor 4DM, summed stress score (SSS) was calculated using either count-matched or full-count normal data. Studies were classified as low-risk (SSS < 4) or intermediate/high-risk (SSS ≥ 4).


Count reduction using count-matched normal data increases false-normal rate and decreases sensitivity. With full-count normal data, count reduction increases false-hypoperfusion rate, leading to decreased specificity. Altogether, rate of reclassification was significant at roughly 67% dose and below.


Significant bias results from count level of normal data relative to actual patient data. Compared to standard LEHR, IQ-SPECT should allow for significant dose reduction.

Key Words

MPI SPECT/CT Tc-99m MIBI dose reduction normal data 



Myocardial perfusion imaging


Total perfusion deficit


Summed stress score


Summed rest score


Acquisition time


Imaging time


Counts per pixel



The present work was performed in (partial) fulfillment of the requirements for obtaining the degree “Dr. med.”


Matthias Wetzl has nothing to declare. James C. Sanders has been supported in the past by a collaboration agreement with Siemens Molecular Imaging that is not directly related to this project. Torsten Kuwert has received honoraria for lectures on behalf of Siemens Molecular Imaging. Torsten Kuwert and Philipp Ritt: the Clinic of Nuclear Medicine in Erlangen has a research cooperation with Siemens on the field of SPECT/CT, but not related to the data contained in this manuscript.

Supplementary material

12350_2018_1272_MOESM1_ESM.pptx (255 kb)
Supplementary material 1 (PPTX 255 kb)


  1. 1.
    Zheng ZJ, Croft JB, Giles WH, Mensah GA. Sudden cardiac death in the United States, 1989 to 1998. Circulation. 2001;104:2158–63.CrossRefPubMedGoogle Scholar
  2. 2.
    Hachamovitch R, Berman DS, Shaw LJ, Kiat H, Cohen I, Cabico JA, et al. Incremental prognostic value of myocardial perfusion single photon emission computed tomography for the prediction of cardiac death: differential stratification for risk of cardiac death and myocardial infarction. Circulation. 1998;97:535–43.CrossRefPubMedGoogle Scholar
  3. 3.
    Underwood SR, Anagnostopoulos C, Cerqueira M, Ell PJ, Flint EJ, Harbinson M, et al. Myocardial perfusion scintigraphy: the evidence. Eur J Nucl Med Mol Imaging. 2004;31:261–91.CrossRefPubMedGoogle Scholar
  4. 4.
    Hendel RC, Berman DS, Di Carli MF, Heidenreich PA, Henkin RE, Pellikka PA, et al. Appropriate use criteria for cardiac radionuclide imaging. J Am Coll Cardiol. 2009;53:2201–29.CrossRefPubMedGoogle Scholar
  5. 5.
    Hutton B. The origins of SPECT and SPECT/CT. Eur J Nucl Med Mol Imaging. 2014;41:3–16.CrossRefGoogle Scholar
  6. 6.
    Okada RD, Glover D, Gaffney T, Williams S. Myocardial kinetics of technetium-99m-hexakis-2-methoxy-2-methylpropyl-isonitrile. Circulation. 1988;77:491–8.CrossRefPubMedGoogle Scholar
  7. 7.
    Dorbala S, Di Carli MF, Delbeke D, Abbara S, DePuey EG, Dilsizian V, et al. SNMMI/ASNC/SCCT guideline for cardiac SPECT/CT and PET/CT 1.0. J Nucl Med. 2013;54:1485–507.CrossRefPubMedGoogle Scholar
  8. 8.
    Hesse B, Tagil K, Cuocolo A, Anagnostopoulos C, Bardies M, Bax J, et al. EANM/ESC procedural guidelines for myocardial perfusion imaging in nuclear cardiology. Eur J Nucl Med Mol Imaging. 2005;32:855–97.CrossRefPubMedGoogle Scholar
  9. 9.
    de Jong MC, Genders TS, van Geuns R-J, Moelker A, Hunink MM. Diagnostic performance of stress myocardial perfusion imaging for coronary artery disease: a systematic review and meta-analysis. Eur Radiol. 2012;22:1881–95.CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Lindner O, Bengel FM, Hacker M, Schäfer W, Burchert W. Use of myocardial perfusion imaging and estimation of associated radiation doses in Germany from 2005 to 2012. Eur J Nucl Med Mol Imaging. 2014;41:963–71.CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    Duvall WL, Croft L, Godiwala T, Ginsberg E, George T, Henzlova M. Reduced isotope dose with rapid SPECT MPI imaging: Initial experience with a CZT SPECT camera. J Nucl Cardiol. 2010;17:1009–14.CrossRefPubMedGoogle Scholar
  12. 12.
    Bocher M, Blevis IM, Tsukerman L, Shrem Y, Kovalski G, Volokh L. A fast cardiac gamma camera with dynamic SPECT capabilities: design, system validation and future potential. Eur J Nucl Med Mol Imaging. 2010;37:1887–902.CrossRefPubMedPubMedCentralGoogle Scholar
  13. 13.
    DePuey EG. Advances in SPECT camera software and hardware: currently available and new on the horizon. J Nucl Cardiol. 2012;19:551–81.CrossRefPubMedGoogle Scholar
  14. 14.
    Vija AH, Malmin R, Yahil A, Zeintl J, Bhattacharya M, Rempel TD et al. A method for improving the efficiency of myocardial perfusion imaging using conventional SPECT and SPECT/CT imaging systems. In: Nuclear Science Symposium Conference Record (NSS/MIC), 2010 IEEE; 2010. p. 3433-7.Google Scholar
  15. 15.
    Zeintl J, Rempel TD, Bhattacharya M, Malmin RE, Vija AH. Performance characteristics of the SMARTZOOM collimator. In: Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE; 2011. p. 2426-9.Google Scholar
  16. 16.
    Erwin WD, Jessop AC, Mar MV, Macapinlac HA, Mawlawi OR. Qualitative and quantitative comparison of gated blood pool single photon emission computed tomography using low-energy high-resolution and SMARTZOOM collimation. Nucl Med Commun. 2017;38:35–43.CrossRefPubMedGoogle Scholar
  17. 17.
    Pirich C, Keinrath P, Barth G, Rendl G, Rettenbacher L, Rodrigues M. Diagnostic accuracy and functional parameters of myocardial perfusion scintigraphy using accelerated cardiac acquisition with IQ SPECT technique in comparison to conventional imaging. Q J Nucl Med Mol Imaging. 2017;61:102–7.PubMedGoogle Scholar
  18. 18.
    Caobelli F, Pizzocaro C, Paghera B, Guerra UP. Evaluation of patients with coronary artery disease. IQ-SPECT protocol in myocardial perfusion imaging: Preliminary results. Nuklearmedizin. 2013;52:178–85.CrossRefPubMedGoogle Scholar
  19. 19.
    Lyon MC, Foster C, Ding X, Dorbala S, Spence D, Bhattacharya M, et al. Dose reduction in half-time myocardial perfusion SPECT-CT with multifocal collimation. J Nucl Cardiol. 2016;23:657–67.CrossRefPubMedGoogle Scholar
  20. 20.
    Havel M, Kolacek M, Kaminek M, Dedek V, Kraft O, Sirucek P. Myocardial perfusion imaging parameters: IQ-SPECT and conventional SPET system comparison. Hell J Nucl Med. 2014;17:200–3.PubMedGoogle Scholar
  21. 21.
    Novak M, Grancorvitz A, Johnson C. Comparison of IQ-SPECT/CT with conventional SPECT/CT for myocardial perfusion imaging. J Nucl Med. 2012;53:2712.Google Scholar
  22. 22.
    Erwin W, Jessop A, Peirsol W, Mar M, Jones S, Macapinlac H, et al. Qualitative and quantitative comparison of gated blood pool SPECT using low-energy high-resolution and SMARTZOOM collimation. J Nucl Med. 2014;55:1736.Google Scholar
  23. 23.
    Matsuo S, Nakajima K, Onoguchi M, Wakabayash H, Okuda K, Kinuya S. Nuclear myocardial perfusion imaging using thallium-201 with a novel multifocal collimator SPECT/CT: IQ-SPECT versus conventional protocols in normal subjects. Ann Nucl Med. 2015;29:452–9.CrossRefPubMedGoogle Scholar
  24. 24.
    Du Y, Bhattacharya M, Frey EC. Simultaneous Tc-99m/I-123 dual-radionuclide myocardial perfusion/innervation imaging using Siemens. Phys Med Biol. 2014;59:2813.CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    Henzlova MJ, Duvall WL, Einstein AJ, Travin MI, Verberne HJ. ASNC imaging guidelines for SPECT nuclear cardiology procedures: Stress, protocols, and tracers. J Nucl Cardiol. 2016;23:606–39.CrossRefPubMedGoogle Scholar
  26. 26.
    Holly TA, Abbott BG, Al-Mallah M, Calnon DA, Cohen MC, DiFilippo FP, et al. Single photon-emission computed tomography. J Nucl Cardiol. 2010;17:941–73.CrossRefPubMedGoogle Scholar
  27. 27.
    Bundesamt für Strahlenschutz. Bekanntmachung der aktualisierten diagnostischen Referenzwerte für nuklearmedizinische Untersuchungen [National Regulation]. Bundesanzeiger. 2012;19(10):2012.Google Scholar
  28. 28.
    Verberne HJ, Acampa W, Anagnostopoulos C, Ballinger J, Bengel F, De Bondt P, et al. EANM procedural guidelines for radionuclide myocardial perfusion imaging with SPECT and SPECT/CT: 2015 revision. Eur J Nucl Med Mol Imaging. 2015;42:1929–40.CrossRefPubMedPubMedCentralGoogle Scholar
  29. 29.
    Slomka P, Germano G. Optimizing radiation dose and imaging time with conventional myocardial perfusion SPECT: Technical aspects. J Nucl Cardiol. 2017;24:888–91.CrossRefPubMedGoogle Scholar
  30. 30.
    Ficaro EP, Lee BC, Kritzman JN, Corbett JR. Corridor4DM: The Michigan method for quantitative nuclear cardiology. J Nucl Cardiol. 2007;14:455–65.CrossRefPubMedGoogle Scholar
  31. 31.
    Germano G, Kiat H, Kavanagh PB, Moriel M, Mazzanti M, Su HT, et al. Automatic quantification of ejection fraction from gated myocardial perfusion SPECT. J Nucl Med. 1995;36:2138–47.PubMedGoogle Scholar
  32. 32.
    Germano G, Kavanagh PB, Slomka PJ, Van Kriekinge SD, Pollard G, Berman DS. Quantitation in gated perfusion SPECT imaging: The Cedars-Sinai approach. J Nucl Cardiol. 2007;14:433–54.CrossRefPubMedGoogle Scholar
  33. 33.
    Germano G, Kavanagh PB, Waechter P, Areeda J, Van Kriekinge S, Sharir T, et al. A new algorithm for the quantitation of myocardial perfusion SPECT. I: Technical principles and reproducibility. J Nucl Med. 2000;41:712–9.PubMedGoogle Scholar
  34. 34.
    Garcia EV, Faber TL, Cooke CD, Folks RD, Chen J, Santana C. The increasing role of quantification in clinical nuclear cardiology: The Emory approach. J Nucl Cardiol. 2007;14:420–32.CrossRefPubMedGoogle Scholar
  35. 35.
    Slomka PJ, Nishina H, Berman DS, Akincioglu C, Abidov A, Friedman JD, et al. Automated quantification of myocardial perfusion SPECT using simplified normal limits. J Nucl Cardiol. 2005;12:66–77.CrossRefPubMedGoogle Scholar
  36. 36.
    Rubeaux M, Xu Y, Germano G, Berman DS, Slomka PJ. Normal databases for the relative quantification of myocardial perfusion. Curr Cardiovasc Imaging Rep. 2016;9:22.CrossRefPubMedPubMedCentralGoogle Scholar
  37. 37.
    Slomka PJ, Fish MB, Lorenzo S, Nishina H, Gerlach J, Berman DS, et al. Simplified normal limits and automated quantitative assessment for attenuation-corrected myocardial perfusion SPECT. J Nucl Cardiol. 2006;13:642–51.CrossRefPubMedGoogle Scholar
  38. 38.
    Nakajima K, Matsumoto N, Kasai T, Matsuo S, Kiso K, Okuda K. Normal values and standardization of parameters in nuclear cardiology: Japanese Society of Nuclear Medicine working group database. Ann Nucl Med. 2016;30:188–99.CrossRefPubMedPubMedCentralGoogle Scholar
  39. 39.
    Sharir T, Pinskiy M, Pardes A, Rochman A, Prokhorov V, Kovalski G, et al. Comparison of the diagnostic accuracies of very low stress-dose with standard-dose myocardial perfusion imaging: Automated quantification of one-day, stress-first SPECT using a CZT camera. J Nucl Cardiol. 2016;23:11–20.CrossRefPubMedGoogle Scholar
  40. 40.
    Esteves FP, Galt JR, Folks RD, Verdes L, Garcia EV. Diagnostic performance of low-dose rest/stress Tc-99m tetrofosmin myocardial perfusion SPECT using the 530c CZT camera: quantitative vs visual analysis. J Nucl Cardiol. 2014;21:158–65.CrossRefPubMedGoogle Scholar
  41. 41.
    Nakazato R, Berman DS, Hayes SW, Fish M, Padgett R, Xu Y, et al. Myocardial perfusion imaging with a solid-state camera: simulation of a very low dose imaging protocol. J Nucl Med. 2013;54:373–9.CrossRefPubMedPubMedCentralGoogle Scholar
  42. 42.
    Siemens Molecular Imaging. IQ-SPECT Hints and Tips Software Version VA60A [Manufacturer’s White Paper]; 2011.Google Scholar
  43. 43.
    Lindner O, Bengel F, Burchert W, Hacker M, Schäfer W, Schäfers M et al. DGN-Handlungsempfehlung (S1-Leitlinie): Myokard-Perfusions-Szintigraphie [National Guideline]; 2012.Google Scholar
  44. 44.
    Berman DS, Kang X, Van Train KF, Lewin HC, Cohen I, Areeda J, et al. Comparative prognostic value of automatic quantitative analysis versus semiquantitative visual analysis of exercise myocardial perfusion single-photon emission computed tomography. J Am Coll Cardiol. 1998;32:1987–95.CrossRefPubMedGoogle Scholar
  45. 45.
    Lecchi M, Martinelli I, Zoccarato O, Maioli C, Lucignani G, Del Sole A. Comparative analysis of full-time, half-time, and quarter-time myocardial ECG-gated SPECT quantification in normal-weight and overweight patients. J Nucl Cardiol. 2017;24:876–87.CrossRefPubMedGoogle Scholar
  46. 46.
    Caobelli F, Thackeray JT, Soffientini A, Bengel FM, Pizzocaro C, Guerra UP. Feasibility of one-eighth time gated myocardial perfusion SPECT functional imaging using IQ-SPECT. Eur J Nucl Med Mol Imaging. 2015;42:1–9.CrossRefGoogle Scholar
  47. 47.
    Meden J, Ficaro E, Corbett J. Clinical comparison of four minute IQ-SPECT imaging with conventional parallel hole collimated SPECT/CT. J Nucl Med Meeting Abstracts 2011;52:1132Google Scholar
  48. 48.
    Matsutomo N, Nagaki A, Sasaki M. Performance of myocardial perfusion imaging using multi-focus fan beam collimator with resolution recovery reconstruction in a comparison with conventional SPECT. Asia Ocean J Nucl Med Biol. 2014;2:111–9.PubMedPubMedCentralGoogle Scholar
  49. 49.
    Agostini D, Pineau S, Manrique A, Desmonts C. Assessment of myocardial perfusion and function by IQ-SPECT in comparison with LEHR-SPECT in patients suspected of coronary artery disease: Preliminary results. J Nucl Med Meeting Abstracts 2014;55:1717Google Scholar

Copyright information

© American Society of Nuclear Cardiology 2018

Authors and Affiliations

  • Matthias Wetzl
    • 1
  • James C. Sanders
    • 1
    • 2
  • Torsten Kuwert
    • 1
  • Philipp Ritt
    • 1
  1. 1.Clinic of Nuclear MedicineFriedrich-Alexander-University Erlangen-Nürnberg (FAU)ErlangenGermany
  2. 2.Pattern Recognition LabFriedrich-Alexander-University Erlangen-Nürnberg (FAU)ErlangenGermany

Personalised recommendations