{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T06:14:05Z","timestamp":1782454445652,"version":"3.54.5"},"reference-count":30,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2021,10,20]],"date-time":"2021-10-20T00:00:00Z","timestamp":1634688000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"DOI":"10.13039\/100000050","name":"National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["Z1A\u2010HL006214"],"award-info":[{"award-number":["Z1A\u2010HL006214"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["Z1A\u2010HL006257"],"award-info":[{"award-number":["Z1A\u2010HL006257"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Magnetic Resonance Imaging"],"published-print":{"date-parts":[[2022,6]]},"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>MRI T2* and R2* mapping have gained clinical acceptance for noninvasive assessment of iron overload. Lower field MRI may offer increased measurement dynamic range in patients with high iron concentration and may potentially increase MRI accessibility, but it is compromised by lower signal\u2010to\u2010noise ratio that reduces measurement precision.<\/jats:p><\/jats:sec><jats:sec><jats:title>Purpose<\/jats:title><jats:p>To characterize a high\u2010performance 0.55\u2009T MRI system for evaluating patients with liver iron overload.<\/jats:p><\/jats:sec><jats:sec><jats:title>Study Type<\/jats:title><jats:p>Prospective.<\/jats:p><\/jats:sec><jats:sec><jats:title>Population<\/jats:title><jats:p>Forty patients with known or suspected iron overload (sickle cell anemia [<jats:italic>n<\/jats:italic>\u00a0=\u00a05], \u00df<jats:bold>\u2010<\/jats:bold>thalassemia [<jats:italic>n<\/jats:italic>\u00a0=\u00a03], and hereditary spherocytosis [<jats:italic>n<\/jats:italic>\u00a0=\u00a02]) and a liver iron phantom.<\/jats:p><\/jats:sec><jats:sec><jats:title>Field strength\/sequence<\/jats:title><jats:p>A breath\u2010held multiecho gradient echo sequence at 0.55\u2009T and 1.5\u2009T.<\/jats:p><\/jats:sec><jats:sec><jats:title>Assessment<\/jats:title><jats:p>Patients were imaged with T2*\/R2* mapping 0.55\u2009T and 1.5\u2009T within 24\u2009hours, and 16 patients returned for follow\u2010up exams within 6\u201316\u2009months, resulting in 56 paired studies. Liver T2* and R2* measurements and standard deviations were compared between 0.55\u2009T and 1.5\u2009T and used to validate a predictive model between field strengths. The model was then used to classify iron overload at 0.55\u2009T.<\/jats:p><\/jats:sec><jats:sec><jats:title>Statistical Tests<\/jats:title><jats:p>Linear regression and Bland\u2013Altman analysis were used for comparisons, and measurement precision was assessed using the coefficient of variation. A <jats:italic>P<\/jats:italic>\u2010value\u2009&lt;\u20090.05 was considered statistically significant.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>R2* was significantly lower at 0.55\u2009T in our cohort (488\u2009\u00b1\u2009449\u2009s<jats:sup>\u22121<\/jats:sup> at 1.5\u2009T vs. 178\u2009\u00b1\u2009155\u2009s<jats:sup>\u22121<\/jats:sup> at 0.55\u2009T, <jats:italic>n<\/jats:italic>\u00a0=\u00a056 studies) and in the patients with severe iron overload (937\u2009\u00b1\u2009369\u2009s<jats:sup>\u22121<\/jats:sup> at 1.5\u2009T vs. 339\u2009\u00b1\u2009127\u2009s<jats:sup>\u22121<\/jats:sup> at 0.55\u2009T, <jats:italic>n<\/jats:italic>\u00a0=\u00a023 studies). The coefficient of variation indicated reduced precision at 0.55\u2009T (3.5\u2009\u00b1\u20092.2% at 1.5\u2009T vs 6.9\u2009\u00b1\u20093.9% at 0.55\u2009T). The predictive model accurately predicted 1.5\u2009T R2* from 0.55\u2009T R2* (Bland Altman bias\u00a0=\u00a0\u22126.6\u2009\u00b1\u200920.5%). Using this model, iron overload at 0.55\u2009T was classified as: severe R2*\u2009&gt;\u2009185\u2009s<jats:sup>\u22121<\/jats:sup>, moderate 81\u2009s<jats:sup>\u22121<\/jats:sup>\u00a0&lt;\u2009R2*\u2009&lt;\u2009185\u2009s<jats:sup>\u22121<\/jats:sup>, and mild 45\u2009s<jats:sup>\u22121<\/jats:sup>\u00a0&lt; R2*\u2009&lt;\u200991\u2009s<jats:sup>\u22121<\/jats:sup>.<\/jats:p><\/jats:sec><jats:sec><jats:title>Data Conclusion<\/jats:title><jats:p>We demonstrated that 0.55\u2009T provides T2* and R2* maps that can be used for the assessment of liver iron overload in patients.<\/jats:p><\/jats:sec><jats:sec><jats:title>Evidence Level<\/jats:title><jats:p>2<\/jats:p><\/jats:sec><jats:sec><jats:title>Technical Efficacy<\/jats:title><jats:p>Stage 2<\/jats:p><\/jats:sec>","DOI":"10.1002\/jmri.27950","type":"journal-article","created":{"date-parts":[[2021,10,21]],"date-time":"2021-10-21T12:27:17Z","timestamp":1634819237000},"page":"1855-1863","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Evaluation of Hepatic Iron Overload Using a Contemporary 0.<scp>55\u2009T MRI<\/scp> System"],"prefix":"10.1002","volume":"55","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7169-5693","authenticated-orcid":false,"given":"Adrienne E.","family":"Campbell\u2010Washburn","sequence":"first","affiliation":[{"name":"Cardiovascular Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine","family":"Mancini","sequence":"additional","affiliation":[{"name":"Cardiovascular Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Conrey","sequence":"additional","affiliation":[{"name":"Sickle Cell Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lanelle","family":"Edwards","sequence":"additional","affiliation":[{"name":"Systems Biology Center, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sujata","family":"Shanbhag","sequence":"additional","affiliation":[{"name":"Cardiovascular Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Wood","sequence":"additional","affiliation":[{"name":"Department of Cardiology Children's Hospital Los Angeles  California Los Angeles USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui","family":"Xue","sequence":"additional","affiliation":[{"name":"Systems Biology Center, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Kellman","sequence":"additional","affiliation":[{"name":"Systems Biology Center, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"W. Patricia","family":"Bandettini","sequence":"additional","affiliation":[{"name":"Cardiovascular Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Swee Lay","family":"Thein","sequence":"additional","affiliation":[{"name":"Sickle Cell Branch, Division of Intramural Research National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Department of Health and Human Services  Bethesda Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2021,10,20]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1182\/asheducation-2016.1.625"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/jmri.24584"},{"key":"e_1_2_8_4_1","doi-asserted-by":"publisher","DOI":"10.1097\/MOH.0b013e3280d2b76b"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1148\/rg.2018170079"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2004-10-3982"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1186\/1532-429X-16-40"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.22657"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.25459"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.2019190452"},{"key":"e_1_2_8_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/jmri.26637"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.2214\/ajr.168.5.9129412"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1148\/radiology.179.2.2014276"},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF01356827"},{"issue":"1","key":"e_1_2_8_15_1","first-page":"108","article-title":"Geographical variations in current clinical practice on transfusions and iron chelation therapy across various transfusion\u2010dependent anaemias","volume":"11","author":"Viprakasit V","year":"2013","journal-title":"Blood Transfus"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2010-01-251348"},{"key":"e_1_2_8_17_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12968-015-0115-3"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.28278"},{"key":"e_1_2_8_19_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.24389"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.20713"},{"key":"e_1_2_8_21_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12968-014-0106-9"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.1182\/blood.V89.3.739"},{"key":"e_1_2_8_23_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.28452"},{"key":"e_1_2_8_24_1","doi-asserted-by":"publisher","DOI":"10.1155\/2015\/294024"},{"key":"e_1_2_8_25_1","unstructured":"RajendranK TaoS MichalakGJ LengS McColloughCH.Quantifying liver iron content using photon\u2010counting detector based computed tomography. Radiology Society of North America (RSNA) annual meeting. Chicago;2018. SST09\u201009."},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00330-019-06380-9"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-020-74968-z"},{"key":"e_1_2_8_28_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00330-012-2506-2"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0192890"},{"key":"e_1_2_8_30_1","doi-asserted-by":"publisher","DOI":"10.4103\/jcis.JCIS_30_18"},{"key":"e_1_2_8_31_1","doi-asserted-by":"publisher","DOI":"10.1002\/mrm.25868"}],"container-title":["Journal of Magnetic Resonance Imaging"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jmri.27950","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/jmri.27950","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jmri.27950","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T11:39:01Z","timestamp":1692963541000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jmri.27950"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10,20]]},"references-count":30,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2022,6]]}},"alternative-id":["10.1002\/jmri.27950"],"URL":"https:\/\/doi.org\/10.1002\/jmri.27950","archive":["Portico"],"relation":{},"ISSN":["1053-1807","1522-2586"],"issn-type":[{"value":"1053-1807","type":"print"},{"value":"1522-2586","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10,20]]},"assertion":[{"value":"2021-07-13","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2021-09-23","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2021-10-20","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}