{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T14:01:44Z","timestamp":1770818504567,"version":"3.50.1"},"reference-count":20,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2019,12,1]],"date-time":"2019-12-01T00:00:00Z","timestamp":1575158400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T00:00:00Z","timestamp":1577404800000},"content-version":"vor","delay-in-days":26,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100007753","name":"It\u00e4-Suomen Yliopisto","doi-asserted-by":"publisher","award":["The Doctoral Programme in Science, Technology and Computing"],"award-info":[{"award-number":["The Doctoral Programme in Science, Technology and Computing"]}],"id":[{"id":"10.13039\/100007753","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004092","name":"Kuopion Yliopistollinen Sairaala","doi-asserted-by":"publisher","award":["VTR, project 5031351"],"award-info":[{"award-number":["VTR, project 5031351"]}],"id":[{"id":"10.13039\/501100004092","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005432","name":"Pohjois-Savon Rahasto","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100005432","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"crossref","award":["Centre of Excellence in Inverse Modelling and Imaging, project number 312344"],"award-info":[{"award-number":["Centre of Excellence in Inverse Modelling and Imaging, project number 312344"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100004012","name":"Jane ja Aatos Erkon S\u00e4\u00e4ti\u00f6","doi-asserted-by":"publisher","award":["project number 64741"],"award-info":[{"award-number":["project number 64741"]}],"id":[{"id":"10.13039\/501100004012","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["EJNMMI Phys"],"published-print":{"date-parts":[[2019,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n<jats:title>Background<\/jats:title>\n<jats:p>In ordered subsets expectation maximization (OSEM) reconstruction of electrocardiography (ECG)-gated myocardial perfusion single-photon emission computed tomography (SPECT), it is often assumed that the image acquisition time is constant for each projection angle and ECG bin. Due to heart rate variability (HRV), this assumption may lead to errors in quantification of left ventricular mechanical dyssynchrony with phase analysis. We hypothesize that a time-modified OSEM (TOSEM) algorithm provides more robust results.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Methods<\/jats:title>\n<jats:p>List-mode data of 44 patients were acquired with a dual-detector SPECT\/CT system and binned to eight ECG bins. First, activity ratio (AR)\u2014the ratio of total activity in the last OSEM-reconstructed ECG bin and first five ECG bins\u2014was computed, as well as standard deviation SD<jats:sub>R-R<\/jats:sub> of the accepted R\u2013R intervals; their association was evaluated with Pearson correlation analysis. Subsequently, patients whose AR was higher than 90% were selected, and their list-mode data were rebinned by omitting a part of the acquired counts to yield AR values of 90%, 80%, 70%, 60% and 50%. These data sets were reconstructed with OSEM and TOSEM algorithms, and phase analysis was performed. Reliability of both algorithms was assessed by computing concordance correlation coefficients (CCCs) between the 90% data and data corresponding to lower AR values. Finally, phase analysis results assessed from OSEM- and TOSEM-reconstructed images were compared.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>A strong negative correlation (<jats:italic>r<\/jats:italic> = -0.749) was found between SD<jats:sub>R-R<\/jats:sub> and AR. As AR decreased, phase analysis parameters obtained from OSEM images decreased significantly. On the contrary, reduction of AR had no significant effect on phase analysis parameters obtained from TOSEM images (CCC &gt; 0.88). The magnitude of difference between OSEM and TOSEM results increased as AR decreased.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Conclusions<\/jats:title>\n<jats:p>TOSEM algorithm minimizes the HRV-related error and can be used to provide more robust phase analysis results.<\/jats:p>\n<\/jats:sec>","DOI":"10.1186\/s40658-019-0261-z","type":"journal-article","created":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T17:02:58Z","timestamp":1577466178000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Time-modified OSEM algorithm for more robust assessment of left ventricular dyssynchrony with phase analysis in ECG-gated myocardial perfusion SPECT"],"prefix":"10.1186","volume":"6","author":[{"given":"Matti J.","family":"Kortelainen","sequence":"first","affiliation":[]},{"given":"Tuomas M.","family":"Koivum\u00e4ki","sequence":"additional","affiliation":[]},{"given":"Marko J.","family":"Vauhkonen","sequence":"additional","affiliation":[]},{"given":"Mikko A.","family":"Hakulinen","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2019,12,27]]},"reference":[{"key":"261_CR1","doi-asserted-by":"publisher","first-page":"1929","DOI":"10.1007\/s00259-015-3139-x","volume":"42","author":"HJ Verberne","year":"2015","unstructured":"Verberne HJ, Acampa W, Anagnostopoulos C, Ballinger J, Bengel F, De Bondt P, Buechel RR, Cuocolo A, van Eck-Smit BLF, Flotats A, Hacker M, Hindorf C, Kaufmann PA, Lindner O, Ljungberg M, Lonsdale M, Manrique A, Minarik D, Scholte AJHA, Slart RHJA, Tr\u00e4g\u00e5rdh E, de Wit TC, Hesse B. EANM procedural guidelines for radionuclide myocardial perfusion imaging with SPECT and SPECT\/CT: 2015 revision. Eur J Nucl Med Mol Imaging. 2015;42:1929\u201340.","journal-title":"Eur J Nucl Med Mol Imaging"},{"key":"261_CR2","first-page":"306","volume":"8","author":"K Lange","year":"1984","unstructured":"Lange K, Carson R. EM reconstruction algorithms for emission and transmission tomography. J Comput Assist Tomogr. 1984;8:306\u201316.","journal-title":"J Comput Assist Tomogr"},{"key":"261_CR3","first-page":"1272","volume":"29","author":"JE Juni","year":"1988","unstructured":"Juni JE, Chen CC. Effects of gating modes on the analysis of left ventricular function in the presence of heart rate variation. J Nucl Med. 1988;29:1272\u20138.","journal-title":"J Nucl Med"},{"key":"261_CR4","first-page":"38","volume":"31","author":"SL Bacharach","year":"1990","unstructured":"Bacharach SL, Bonow RO, Green MV. Comparison of fixed and variable temporal resolution methods for creating gated cardiac blood-pool image sequences. J Nucl Med. 1990;31:38\u201342.","journal-title":"J Nucl Med"},{"key":"261_CR5","doi-asserted-by":"publisher","first-page":"687","DOI":"10.1016\/j.nuclcard.2005.06.088","volume":"12","author":"J Chen","year":"2005","unstructured":"Chen J, Garcia EV, Folks RD, Cooke CD, Faber TL, Tauxe EL, Iskandrian AE. Onset of left ventricular mechanical contraction as determined by phase analysis of ECG-gated myocardial perfusion SPECT imaging: development of a diagnostic tool for assessment of cardiac mechanical dyssynchrony. J Nucl Cardiol. 2005;12:687\u201395.","journal-title":"J Nucl Cardiol"},{"key":"261_CR6","doi-asserted-by":"publisher","first-page":"1892","DOI":"10.2967\/jnumed.112.106344","volume":"53","author":"DR Ludwig","year":"2012","unstructured":"Ludwig DR, Friehling M, Schwartzman D, Saba S, Follansbee WP, Soman P. On the importance of image gating for the assay of left ventricular mechanical dyssynchrony using SPECT. J Nucl Med. 2012;53:1892\u20136.","journal-title":"J Nucl Med"},{"key":"261_CR7","doi-asserted-by":"publisher","first-page":"118","DOI":"10.1109\/42.552061","volume":"16","author":"JW Wallis","year":"1997","unstructured":"Wallis JW, Miller TR. An optimal rotator for iterative reconstruction. IEEE Trans Med Imaging. 1997;16:118\u201323.","journal-title":"IEEE Trans Med Imaging"},{"key":"261_CR8","first-page":"515","volume":"5","author":"HO Anger","year":"1964","unstructured":"Anger HO. Scintillation Camera with Multichannel Collimators. J Nucl Med. 1964;5:515\u201331.","journal-title":"J Nucl Med"},{"key":"261_CR9","doi-asserted-by":"publisher","first-page":"75","DOI":"10.1007\/BF03027384","volume":"19","author":"M Brambilla","year":"2005","unstructured":"Brambilla M, Cannillo B, Dominietto M, Leva L, Secco C, Inglese E. Characterization of ordered-subsets expectation maximization with 3D post-reconstruction Gauss filtering and comparison with filtered backprojection in 99mTc SPECT. Ann Nucl Med. 2005;19:75\u201382.","journal-title":"Ann Nucl Med"},{"key":"261_CR10","doi-asserted-by":"publisher","first-page":"18","DOI":"10.2967\/jnmt.109.070243","volume":"38","author":"L Ceriani","year":"2010","unstructured":"Ceriani L, Ruberto T, Delaloye AB, Prior JO, Giovanella L. Three-dimensional ordered-subset expectation maximization iterative protocol for evaluation of left ventricular volumes and function by quantitative gated SPECT: a dynamic phantom study. J Nucl Med Technol. 2010;38:18\u201323.","journal-title":"J Nucl Med Technol"},{"key":"261_CR11","doi-asserted-by":"publisher","unstructured":"Pretorius PH, Johnson KL, Dahlberg ST, King MA. Investigation of the physical effects of respiratory motion compensation in a large population of patients undergoing Tc-99m cardiac perfusion SPECT\/CT stress imaging. J Nucl Cardiol. 2017:1\u201316.\u00a0https:\/\/doi.org\/10.1007\/s12350-017-0890-3.","DOI":"10.1007\/s12350-017-0890-3"},{"key":"261_CR12","doi-asserted-by":"publisher","first-page":"601","DOI":"10.1109\/42.363108","volume":"13","author":"HM Hudson","year":"1994","unstructured":"Hudson HM, Larkin RS. Accelerated image reconstruction using ordered subsets of projection data. IEEE Trans Med Imaging. 1994;13:601\u20139.","journal-title":"IEEE Trans Med Imaging"},{"key":"261_CR13","doi-asserted-by":"publisher","first-page":"718","DOI":"10.2967\/jnumed.108.060657","volume":"50","author":"MM Boogers","year":"2009","unstructured":"Boogers MM, Van Kriekinge SD, Henneman MM, Ypenburg C, Van Bommel RJ, Boersma E, Dibbets-Schneider P, Stokkel MP, Schalij MJ, Berman DS, Germano G, Bax JJ. Quantitative gated SPECT-derived phase analysis on gated myocardial perfusion SPECT detects left ventricular dyssynchrony and predicts response to cardiac resynchronization therapy. J Nucl Med. 2009;50:718\u201325.","journal-title":"J Nucl Med"},{"key":"261_CR14","doi-asserted-by":"publisher","first-page":"1790","DOI":"10.2967\/jnumed.108.055160","volume":"49","author":"SD Van Kriekinge","year":"2008","unstructured":"Van Kriekinge SD, Nishina H, Ohba M, Berman DS, Germano G. Automatic global and regional phase analysis from gated myocardial perfusion SPECT imaging: application to the characterization of ventricular contraction in patients with left bundle branch block. J Nucl Med. 2008;49:1790\u20137.","journal-title":"J Nucl Med"},{"key":"261_CR15","doi-asserted-by":"publisher","first-page":"255","DOI":"10.2307\/2532051","volume":"45","author":"LI Lin","year":"1989","unstructured":"Lin LI. A concordance correlation coefficient to evaluate reproducibility. Biometrics. 1989;45:255\u201368.","journal-title":"Biometrics"},{"key":"261_CR16","doi-asserted-by":"publisher","first-page":"443","DOI":"10.1118\/1.4938579","volume":"43","author":"W Qi","year":"2016","unstructured":"Qi W, Yang Y, Wernick MN, Pretorius PH, King MA. Limited-angle effect compensation for respiratory binned cardiac SPECT. Med Phys. 2016;43:443\u201354.","journal-title":"Med Phys"},{"key":"261_CR17","doi-asserted-by":"publisher","first-page":"38","DOI":"10.1111\/cpf.12379","volume":"38","author":"H H\u00e4m\u00e4l\u00e4inen","year":"2018","unstructured":"H\u00e4m\u00e4l\u00e4inen H, Hedman M, Laitinen T, Hedman A, Kivel\u00e4 A, Laitinen T. Reference values for left ventricular systolic synchrony according to phase analysis of ECG-gated myocardial perfusion SPECT. Clin Physiol Funct Imaging. 2018;38:38\u201345.","journal-title":"Clin Physiol Funct Imaging"},{"key":"261_CR18","first-page":"3","volume":"34","author":"GS Lin","year":"2006","unstructured":"Lin GS, Hines HH, Grant G, Taylor K, Ryals C. Automated quantification of myocardial ischemia and wall motion defects by use of cardiac SPECT polar mapping and 4-dimensional surface rendering. J Nucl Med Technol. 2006;34:3\u201317.","journal-title":"J Nucl Med Technol"},{"key":"261_CR19","doi-asserted-by":"publisher","first-page":"383","DOI":"10.1016\/j.nuclcard.2008.02.014","volume":"15","author":"J Chen","year":"2008","unstructured":"Chen J, Faber TL, Cooke CD, Garcia EV. Temporal resolution of multiharmonic phase analysis of ECG-gated myocardial perfusion SPECT studies. J Nucl Cardiol. 2008;15:383\u201391.","journal-title":"J Nucl Cardiol"},{"key":"261_CR20","doi-asserted-by":"publisher","first-page":"165","DOI":"10.1016\/j.biopsycho.2006.04.008","volume":"74","author":"RE De Meersman","year":"2007","unstructured":"De Meersman RE, Stein PK. Vagal modulation and aging. Biol Psychol. 2007;74:165\u201373.","journal-title":"Biol Psychol"}],"container-title":["EJNMMI Physics"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/link.springer.com\/content\/pdf\/10.1186\/s40658-019-0261-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/link.springer.com\/article\/10.1186\/s40658-019-0261-z\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/link.springer.com\/content\/pdf\/10.1186\/s40658-019-0261-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2020,12,26]],"date-time":"2020-12-26T00:12:01Z","timestamp":1608941521000},"score":1,"resource":{"primary":{"URL":"https:\/\/ejnmmiphys.springeropen.com\/articles\/10.1186\/s40658-019-0261-z"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,12]]},"references-count":20,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2019,12]]}},"alternative-id":["261"],"URL":"https:\/\/doi.org\/10.1186\/s40658-019-0261-z","relation":{},"ISSN":["2197-7364"],"issn-type":[{"value":"2197-7364","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,12]]},"assertion":[{"value":"7 May 2019","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 November 2019","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"27 December 2019","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"This study was performed in accordance with the Declaration of Helsinki and was approved by the Research Ethics Committee of the Northern Savo Hospital District (Dno 90\/2011; March 20, 2012). Informed consent was obtained from all human participants included in this study.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"30"}}