{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T00:57:51Z","timestamp":1778029071971,"version":"3.51.4"},"reference-count":41,"publisher":"IOP Publishing","issue":"2","license":[{"start":{"date-parts":[[2025,1,10]],"date-time":"2025-01-10T00:00:00Z","timestamp":1736467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2025,1,10]],"date-time":"2025-01-10T00:00:00Z","timestamp":1736467200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"crossref","award":["569711"],"award-info":[{"award-number":["569711"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100030855","name":"Microsoft AI","doi-asserted-by":"crossref","award":["AI For Health Computational Services"],"award-info":[{"award-number":["AI For Health Computational Services"]}],"id":[{"id":"10.13039\/100030855","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2025,1,19]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>\n                  <jats:italic>Objective<\/jats:italic>. Modeling of the collimator-detector response (CDR) in single photon emission computed tomography (SPECT) reconstruction enables improved resolution and accuracy, and is thus important for quantitative imaging applications such as dosimetry. The implementation of CDR modeling, however, can become a computational bottleneck when there are substantial components of septal penetration and scatter in the acquired data, since a direct convolution-based approach requires large 2D kernels. This work proposes a 1D convolution and rotation-based CDR model that reduces reconstruction times but maintains consistency with models that employ 2D convolutions. To enable open-source development and use of these models in image reconstruction, we release a SPECTPSFToolbox repository for the PyTomography project on GitHub. <jats:italic>Approach<\/jats:italic>. A 1D\/rotation-based CDR model was formulated and subsequently fit to Monte Carlo (MC) point source data representative of <jats:sup>177<\/jats:sup>Lu, <jats:sup>131<\/jats:sup>I, and <jats:sup>225<\/jats:sup>Ac imaging. Computation times of (i) the proposed 1D\/rotation-based model and (ii) a traditional model that uses 2D convolutions were compared for typical SPECT matrix sizes. Both CDR models were then used in the reconstruction of MC, physical phantom, and patient data; the models were compared by quantifying total counts in hot regions of interest (ROIs) and activity contrast between hot ROIs and background regions. <jats:italic>Results<\/jats:italic>. For typical matrix sizes in SPECT reconstruction, application of the 1D\/rotation-based model provides a two-fold computational speed-up over the 2D model when running on GPU. Only small differences between the 1D\/rotation-based and 2D models (order of 1%) were obtained for count and contrast quantification in select ROIs. <jats:italic>Significance<\/jats:italic>. A technique for CDR modeling in SPECT was proposed that (i) significantly speeds up reconstruction times, and (ii) yields nearly identical reconstructions to traditional 2D convolution based CDR techniques. The released toolbox will permit open-source development of similar models for different isotopes and collimators.<\/jats:p>","DOI":"10.1088\/1361-6560\/ada10a","type":"journal-article","created":{"date-parts":[[2024,12,18]],"date-time":"2024-12-18T22:58:52Z","timestamp":1734562732000},"page":"025002","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":7,"title":["Computationally efficient collimator-detector response compensation in high energy SPECT using 1D convolutions and rotations"],"prefix":"10.1088","volume":"70","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3182-2782","authenticated-orcid":true,"given":"Lucas A","family":"Polson","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pedro","family":"Esquinas","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sara","family":"Kurkowska","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenguang","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3053-2641","authenticated-orcid":true,"given":"Peyman","family":"Sheikhzadeh","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5011-897X","authenticated-orcid":true,"given":"Mehrshad","family":"Abbassi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Saeed","family":"Farzanehfar","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seyyede","family":"Mirabedian","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3127-7478","authenticated-orcid":true,"given":"Carlos","family":"Uribe","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9980-2403","authenticated-orcid":true,"given":"Arman","family":"Rahmim","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2025,1,10]]},"reference":[{"key":"pmbada10abib1","doi-asserted-by":"crossref","DOI":"10.1161\/HCI.0000000000000020","article-title":"Contemporary cardiac SPECT imaging-innovations and best practices: an information statement from the American Society of Nuclear Cardiology","volume":"11","author":"Abbott","year":"2018","journal-title":"Circ. Cardiovasc. Imaging"},{"key":"pmbada10abib2","doi-asserted-by":"publisher","first-page":"1448","DOI":"10.1007\/s00259-017-3716-2","article-title":"Overall survival and response pattern of castration-resistant metastatic prostate cancer to multiple cycles of radioligand therapy using [177Lu]Lu-PSMA-617","volume":"44","author":"Ahmadzadehfar","year":"2017","journal-title":"Eur. J. Nucl. Med. Mol. Imaging"},{"key":"pmbada10abib3","doi-asserted-by":"publisher","first-page":"40","DOI":"10.2174\/1874440001105010040","article-title":"Brain SPECT imaging in complex psychiatric cases: an evidence-based, underutilized tool","volume":"5","author":"Amen","year":"2011","journal-title":"Open Neuroimaging J."},{"key":"pmbada10abib4","doi-asserted-by":"publisher","first-page":"1467","DOI":"10.2967\/jnumed.124.267482","article-title":"Development of a 213bi-labeled pyridyl benzofuran for targeted \u03b1-therapy of amyloid-\u03b2 aggregates","volume":"65","author":"Bender","year":"2024","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib5","doi-asserted-by":"publisher","first-page":"2969","DOI":"10.7150\/thno.96403","article-title":"Actinium-225 targeted alpha particle therapy for prostate cancer","volume":"14","author":"Bidkar","year":"2024","journal-title":"Theranostics"},{"key":"pmbada10abib6","doi-asserted-by":"publisher","first-page":"295","DOI":"10.1109\/TMI.2012.2225441","article-title":"Correction for collimator-detector response in SPECT using point spread function template","volume":"32","author":"Chun","year":"2013","journal-title":"IEEE Trans. Med. Imaging"},{"key":"pmbada10abib7","doi-asserted-by":"publisher","first-page":"1280","DOI":"10.1007\/s00259-022-06092-1","article-title":"Biodistribution and dosimetry for combined [177Lu]Lu-PSMA-I&T\/[225Ac]Ac-PSMA-I&T therapy using multi-isotope quantitative SPECT imaging","volume":"50","author":"Delker","year":"2023","journal-title":"Eur. J. Nucl. Med. Mol. Imaging"},{"key":"pmbada10abib8","doi-asserted-by":"publisher","first-page":"668","DOI":"10.1109\/TNS.2002.1039547","article-title":"Combination of MCNP and SimSET for Monte Carlo simulation of SPECT with medium- and high-energy photons","volume":"49","author":"Du","year":"2002","journal-title":"IEEE Trans. Nucl. Sci."},{"key":"pmbada10abib9","article-title":"Targeted alpha therapy with 225Actinium-PSMA-I&T of castration-resistant prostate cancer (TATCIST)","author":"Excel Diagnostics and Nuclear Oncology Center","year":"2023"},{"key":"pmbada10abib10","first-page":"pp 141","author":"Frey","year":"2006"},{"key":"pmbada10abib11","doi-asserted-by":"publisher","first-page":"941","DOI":"10.1088\/0031-9155\/43\/4\/021","article-title":"Improved estimation of the detector response function for converging beam collimators","volume":"43","author":"Frey","year":"1998","journal-title":"Phys. Med. Biol."},{"key":"pmbada10abib12","doi-asserted-by":"publisher","first-page":"797","DOI":"10.1016\/S0140-6736(21)00237-3","article-title":"[177Lu]Lu]Lu-PSMA-617 versus cabazitaxel in patients with metastatic castration-resistant prostate cancer (TheraP): a randomised, open-label, phase 2 trial","volume":"397","author":"Hofman","year":"2021","journal-title":"Lancet"},{"key":"pmbada10abib13","doi-asserted-by":"publisher","first-page":"4543","DOI":"10.1088\/0031-9155\/49\/19\/007","article-title":"GATE: a simulation toolkit for PET and SPECT","volume":"49","author":"Jan","year":"2004","journal-title":"Phys. Med. Biol."},{"key":"pmbada10abib14","doi-asserted-by":"publisher","first-page":"1734","DOI":"10.1200\/JCO.23.01241","article-title":"George sgouros and RPT-TEC group. How can radiopharmaceutical therapies reach their full potential? improving dose reporting and phase I clinical trial design","volume":"42","author":"Kiess","year":"2024","journal-title":"J. Clin. Oncol."},{"key":"pmbada10abib15","doi-asserted-by":"publisher","first-page":"581","DOI":"10.3390\/tomography7040050","article-title":"SPECT\/CT in the evaluation of suspected skeletal pathology","volume":"7","author":"Koppula","year":"2021","journal-title":"Tomography"},{"key":"pmbada10abib16","doi-asserted-by":"publisher","first-page":"1941","DOI":"10.2967\/jnumed.116.178673","article-title":"225Ac-PSMA-617 for PSMA-targeted \u03b1-radiation therapy of metastatic castration-resistant prostate cancer","volume":"57","author":"Kratochwil","year":"2016","journal-title":"J. Nucl. Med. Official Publ. Soc. Nucl. Med."},{"key":"pmbada10abib17","doi-asserted-by":"publisher","first-page":"795","DOI":"10.2967\/jnumed.117.203539","article-title":"Targeted \u03b1-therapy of metastatic castration-resistant prostate cancer with 225Ac-PSMA-617: swimmer-plot analysis suggests efficacy regarding duration of tumor control","volume":"59","author":"Kratochwil","year":"2018","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib18","doi-asserted-by":"publisher","first-page":"901","DOI":"10.1097\/01.mnm.0000239478.46157.64","article-title":"Characterization of septal penetration in 511 kev SPECT","volume":"27","author":"Laymon","year":"2006","journal-title":"Nucl. Med. Commun."},{"key":"pmbada10abib19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TMI.2024.3420228","article-title":"Joint regional uptake quantification of thorium-227 and radium-223 using a multiple-energy-window projection-domain quantitative SPECT method","volume":"43","author":"Li","year":"2024","journal-title":"IEEE Trans. Med. Imaging"},{"key":"pmbada10abib20","doi-asserted-by":"publisher","first-page":"2504","DOI":"10.1007\/s00259-024-06681-2","article-title":"Image-based dosimetry for [225Ac]Ac-PSMA-I&T therapy and the effect of daughter-specific pharmacokinetics","volume":"51","author":"Liubchenko","year":"2024","journal-title":"Eur. J. Nucl. Med. Mol. Imaging"},{"key":"pmbada10abib21","doi-asserted-by":"publisher","first-page":"151","DOI":"10.2967\/jnumed.115.159012","article-title":"MIRD pamphlet no. 26: joint EANM\/MIRD guidelines for quantitative 177Lu SPECT applied for dosimetry of radiopharmaceutical therapy","volume":"57","author":"Ljungberg","year":"2016","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib22","first-page":"pp 3584","article-title":"A new collimator simulation in simind based on the delta-scattering technique","volume":"vol 6","author":"Ljungberg","year":"2004"},{"key":"pmbada10abib23","doi-asserted-by":"publisher","first-page":"257","DOI":"10.1016\/0169-2607(89)90111-9","article-title":"A Monte Carlo program for the simulation of scintillation camera characteristics","volume":"29","author":"Ljungberg","year":"1989","journal-title":"Comput. Methods Programs Biomed."},{"key":"pmbada10abib24","doi-asserted-by":"publisher","first-page":"1059","DOI":"10.1088\/0031-9155\/25\/6\/003","article-title":"The geometric transfer function component for scintillation camera collimators with straight parallel holes","volume":"25","author":"Metz","year":"1980","journal-title":"Phys. Med. Biol."},{"key":"pmbada10abib25","doi-asserted-by":"publisher","first-page":"1772","DOI":"10.2967\/jnumed.123.265433","article-title":"Tandem isotope therapy with 225Ac-and 177Lu-PSMA-617 in a murine model of prostate cancer","volume":"64","author":"Meyer","year":"2023","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib26","doi-asserted-by":"publisher","DOI":"10.1016\/j.heliyon.2021.e07196","article-title":"Validation of a simind Monte Carlo modelled gamma camera for iodine-123 and iodine-131 imaging","volume":"7","author":"Morphis","year":"2021","journal-title":"Heliyon"},{"key":"pmbada10abib27","doi-asserted-by":"publisher","first-page":"TS5100","DOI":"10.1200\/JCO.2022.40.16_suppl.TPS5100","article-title":"Phase I\/II study of 225Ac-J591 plus 177Lu-PSMA-I&T for progressive metastatic castration-resistant prostate cancer","volume":"40","author":"Nauseef","year":"2022","journal-title":"J. Clin. Oncol."},{"key":"pmbada10abib28","doi-asserted-by":"publisher","DOI":"10.1016\/j.softx.2024.102020","article-title":"PyTomography: a Python library for medical image reconstruction","volume":"29","author":"Polson","year":"2024","journal-title":"SoftwareX"},{"key":"pmbada10abib29","doi-asserted-by":"publisher","first-page":"85","DOI":"10.2967\/jnumed.116.183194","article-title":"German multicenter study investigating [177Lu]Lu-PSMA-617 radioligand therapy in advanced prostate cancer patients","volume":"58","author":"Rahbar","year":"2017","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib30","doi-asserted-by":"publisher","first-page":"3359","DOI":"10.1088\/0031-9155\/43\/11\/013","article-title":"Geometrical response of multihole collimators","volume":"43","author":"Robert Formiconi","year":"1998","journal-title":"Phys. Med. Biol."},{"key":"pmbada10abib31","doi-asserted-by":"publisher","first-page":"4050","DOI":"10.7150\/thno.56211","article-title":"Molecular imaging and biochemical response assessment after a single cycle of [225Ac]Ac-PSMA-617\/[177Lu]Lu-PSMA-617 tandem therapy in mCRPC patients who have progressed on [177Lu]Lu-PSMA-617 monotherapy","volume":"11","author":"Rosar","year":"2021","journal-title":"Theranostics"},{"key":"pmbada10abib32","doi-asserted-by":"publisher","first-page":"1091","DOI":"10.1056\/NEJMoa2107322","article-title":"Lutetium-177-PSMA-617 for metastatic castration-resistant prostate cancer","volume":"385","author":"Sartor","year":"2021","journal-title":"New Engl. J. Med."},{"key":"pmbada10abib33","doi-asserted-by":"publisher","first-page":"62","DOI":"10.2967\/jnumed.119.229229","article-title":"Predictors of overall and disease-free survival in metastatic castration-resistant prostate cancer patients receiving 225Ac-PSMA-617 radioligand therapy","volume":"61","author":"Sathekge","year":"2020","journal-title":"J. Nucl. Med."},{"key":"pmbada10abib34","first-page":"S152\u2013S153O","article-title":"AcTION: a phase 1 study of [225Ac]Ac-PSMA-617 in men with PSMA-positive prostate cancer with or without prior [177Lu]Lu-PSMA-617 radioligand therapy","volume":"50","author":"Sathekge","year":"2023","journal-title":"Eur. J. Nucl. Med. Mol. Imaging"},{"key":"pmbada10abib35","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1038\/s41573-020-0073-9","article-title":"Radiopharmaceutical therapy in cancer: clinical advances and challenges","volume":"19","author":"Sgouros","year":"2020","journal-title":"Nat. Rev. Drug Discovery"},{"key":"pmbada10abib36","doi-asserted-by":"publisher","first-page":"114","DOI":"10.1200\/JCO.2020.38.6_suppl.114","article-title":"Dose-escalation results of a phase I study of 225Ac-J591 for progressive metastatic castration resistant prostate cancer (mCRPC)","volume":"38","author":"Tagawa","year":"2020","journal-title":"J. Clin. Oncol."},{"key":"pmbada10abib37","doi-asserted-by":"publisher","first-page":"1000","DOI":"10.1109\/TMI.2017.2786865","article-title":"Fast quasi-Newton algorithms for penalized reconstruction in emission tomography and further improvements via preconditioning","volume":"37","author":"Tsai","year":"2018","journal-title":"IEEE Trans. Med. Imaging"},{"key":"pmbada10abib38","doi-asserted-by":"publisher","first-page":"81","DOI":"10.1088\/0031-9155\/35\/1\/008","article-title":"The geometric transfer function for cone and fan beam collimators","volume":"35","author":"Tsui","year":"1990","journal-title":"Phys. Med. Biol."},{"key":"pmbada10abib39","doi-asserted-by":"publisher","first-page":"2","DOI":"10.1186\/s40658-016-0170-3","article-title":"Accuracy of 177Lu activity quantification in SPECT imaging: a phantom study","volume":"4","author":"Uribe","year":"2017","journal-title":"EJNMMI Phys."},{"key":"pmbada10abib40","doi-asserted-by":"publisher","first-page":"4796","DOI":"10.1118\/1.4927061","article-title":"Review of SPECT collimator selection, optimization and fabrication for clinical and preclinical imaging","volume":"42","author":"Van Audenhaege","year":"2015","journal-title":"Med. Phys."},{"key":"pmbada10abib41","doi-asserted-by":"publisher","first-page":"669","DOI":"10.2967\/jnumed.120.251017","article-title":"First clinical results for PSMA-targeted \u03b1-therapy using 225Ac-PSMA-I&T in advanced-mCRPC patients","volume":"62","author":"Zacherl","year":"2021","journal-title":"J. Nucl. Med."}],"container-title":["Physics in Medicine &amp; Biology"],"original-title":[],"link":[{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a","content-type":"text\/html","content-version":"am","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"am","intended-application":"similarity-checking"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,1,10]],"date-time":"2025-01-10T06:20:28Z","timestamp":1736490028000},"score":1,"resource":{"primary":{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1361-6560\/ada10a"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,10]]},"references-count":41,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,1,10]]},"published-print":{"date-parts":[[2025,1,19]]}},"URL":"https:\/\/doi.org\/10.1088\/1361-6560\/ada10a","relation":{},"ISSN":["0031-9155","1361-6560"],"issn-type":[{"value":"0031-9155","type":"print"},{"value":"1361-6560","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1,10]]},"assertion":[{"value":"Computationally efficient collimator-detector response compensation in high energy SPECT using 1D convolutions and rotations","name":"article_title","label":"Article Title"},{"value":"Physics in Medicine & Biology","name":"journal_title","label":"Journal Title"},{"value":"paper","name":"article_type","label":"Article Type"},{"value":"\u00a9 2025 The Author(s). Published on behalf of Institute of Physics and Engineering in Medicine by IOP Publishing Ltd","name":"copyright_information","label":"Copyright Information"},{"value":"2024-09-04","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2024-12-18","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2025-01-10","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}