Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map

Myelin water fraction (MWF) is often obtained from a multiple echo spin echo (MESE) sequence using multi-component T fitting with non-negative least squares. This process fits many unknowns including B to produce a T spectrum for each voxel. Presented is an alternative using a rapid B mapping sequen...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Magnetic resonance in medicine 2022-09, Vol.88 (3), p.1380-1390
Hauptverfasser: Mehdizadeh, Nima, Wilman, Alan H
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
container_end_page 1390
container_issue 3
container_start_page 1380
container_title Magnetic resonance in medicine
container_volume 88
creator Mehdizadeh, Nima
Wilman, Alan H
description Myelin water fraction (MWF) is often obtained from a multiple echo spin echo (MESE) sequence using multi-component T fitting with non-negative least squares. This process fits many unknowns including B to produce a T spectrum for each voxel. Presented is an alternative using a rapid B mapping sequence to supply B for the MWF fitting procedure. Effects of B errors on MWF calculations were modeled for 2D and 3D MESE using Bloch and extended phase graph simulations, respectively. Variations in SNR and relative refocusing widths were tested. Human brain experiments at 3 T used 2D MESE and an independent B map. MWF maps were produced with the standard approach and with the use of the independent B map. Differences in B and mean MWF in specific brain regions were compared. For 2D MESE, MWF with the standard method was strongly affected by B misestimations arising from limited SNR and response asymmetry around 180°, which decreased with increasing relative refocusing width. Using an independent B map increased mean MWF and decreased coefficient of variation. Notable differences in vivo in 2D MESE were in areas of high B such as thalamus and splenium where mean MWF increased by 88% and 31%, respectively (P 
doi_str_mv 10.1002/mrm.29286
format Article
fullrecord <record><control><sourceid>pubmed_cross</sourceid><recordid>TN_cdi_crossref_primary_10_1002_mrm_29286</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>35576121</sourcerecordid><originalsourceid>FETCH-LOGICAL-c971-412589079f7dfee06f6e525a8923a2914e3492babf299988a8d9260488582023</originalsourceid><addsrcrecordid>eNo9kDtPwzAQgC0EoqUw8AeQV4RS7Iud-EaoeElFDLAwRW5yhqA4iexUqP-etAWGe-juuxs-xs6lmEsh4NoHPwcEkx2wqdQACWhUh2wqciWSVKKasJMYv4QQiLk6ZpNU6zyTIKfs_XlDTd3ybztQ4C7Ycqi7lnvb93X7MQ46z_26Geq-IU7lZ8fjuNh1FLltqzF43VbU05jagd9yya-296fsyNkm0tlvnbHX-7u3xWOyfHl4WtwskxJzmSgJ2qDI0eWVIxKZy0iDtgYhtYBSUaoQVnblABGNsaZCyIQyRhsQkM7Y5f5rGboYA7miD7W3YVNIUWzlFKOcYidnZC_2bL9eear-yT8b6Q_YUF31</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map</title><source>Access via Wiley Online Library</source><creator>Mehdizadeh, Nima ; Wilman, Alan H</creator><creatorcontrib>Mehdizadeh, Nima ; Wilman, Alan H</creatorcontrib><description>Myelin water fraction (MWF) is often obtained from a multiple echo spin echo (MESE) sequence using multi-component T fitting with non-negative least squares. This process fits many unknowns including B to produce a T spectrum for each voxel. Presented is an alternative using a rapid B mapping sequence to supply B for the MWF fitting procedure. Effects of B errors on MWF calculations were modeled for 2D and 3D MESE using Bloch and extended phase graph simulations, respectively. Variations in SNR and relative refocusing widths were tested. Human brain experiments at 3 T used 2D MESE and an independent B map. MWF maps were produced with the standard approach and with the use of the independent B map. Differences in B and mean MWF in specific brain regions were compared. For 2D MESE, MWF with the standard method was strongly affected by B misestimations arising from limited SNR and response asymmetry around 180°, which decreased with increasing relative refocusing width. Using an independent B map increased mean MWF and decreased coefficient of variation. Notable differences in vivo in 2D MESE were in areas of high B such as thalamus and splenium where mean MWF increased by 88% and 31%, respectively (P &lt; 0.001). Simulations also demonstrated the advantages of this approach for 3D MESE when SNR is &lt;500. For 2D MESE, because of increased complexity of decay curves and limited SNR, supplying B improves MWF results in peripheral and central brain regions where flip angles differ substantially from 180°.</description><identifier>ISSN: 0740-3194</identifier><identifier>EISSN: 1522-2594</identifier><identifier>DOI: 10.1002/mrm.29286</identifier><identifier>PMID: 35576121</identifier><language>eng</language><publisher>United States</publisher><ispartof>Magnetic resonance in medicine, 2022-09, Vol.88 (3), p.1380-1390</ispartof><rights>2022 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c971-412589079f7dfee06f6e525a8923a2914e3492babf299988a8d9260488582023</citedby><cites>FETCH-LOGICAL-c971-412589079f7dfee06f6e525a8923a2914e3492babf299988a8d9260488582023</cites><orcidid>0000-0003-3656-0029</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,780,784,27924,27925</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/35576121$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Mehdizadeh, Nima</creatorcontrib><creatorcontrib>Wilman, Alan H</creatorcontrib><title>Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map</title><title>Magnetic resonance in medicine</title><addtitle>Magn Reson Med</addtitle><description>Myelin water fraction (MWF) is often obtained from a multiple echo spin echo (MESE) sequence using multi-component T fitting with non-negative least squares. This process fits many unknowns including B to produce a T spectrum for each voxel. Presented is an alternative using a rapid B mapping sequence to supply B for the MWF fitting procedure. Effects of B errors on MWF calculations were modeled for 2D and 3D MESE using Bloch and extended phase graph simulations, respectively. Variations in SNR and relative refocusing widths were tested. Human brain experiments at 3 T used 2D MESE and an independent B map. MWF maps were produced with the standard approach and with the use of the independent B map. Differences in B and mean MWF in specific brain regions were compared. For 2D MESE, MWF with the standard method was strongly affected by B misestimations arising from limited SNR and response asymmetry around 180°, which decreased with increasing relative refocusing width. Using an independent B map increased mean MWF and decreased coefficient of variation. Notable differences in vivo in 2D MESE were in areas of high B such as thalamus and splenium where mean MWF increased by 88% and 31%, respectively (P &lt; 0.001). Simulations also demonstrated the advantages of this approach for 3D MESE when SNR is &lt;500. For 2D MESE, because of increased complexity of decay curves and limited SNR, supplying B improves MWF results in peripheral and central brain regions where flip angles differ substantially from 180°.</description><issn>0740-3194</issn><issn>1522-2594</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2022</creationdate><recordtype>article</recordtype><recordid>eNo9kDtPwzAQgC0EoqUw8AeQV4RS7Iud-EaoeElFDLAwRW5yhqA4iexUqP-etAWGe-juuxs-xs6lmEsh4NoHPwcEkx2wqdQACWhUh2wqciWSVKKasJMYv4QQiLk6ZpNU6zyTIKfs_XlDTd3ybztQ4C7Ycqi7lnvb93X7MQ46z_26Geq-IU7lZ8fjuNh1FLltqzF43VbU05jagd9yya-296fsyNkm0tlvnbHX-7u3xWOyfHl4WtwskxJzmSgJ2qDI0eWVIxKZy0iDtgYhtYBSUaoQVnblABGNsaZCyIQyRhsQkM7Y5f5rGboYA7miD7W3YVNIUWzlFKOcYidnZC_2bL9eear-yT8b6Q_YUF31</recordid><startdate>202209</startdate><enddate>202209</enddate><creator>Mehdizadeh, Nima</creator><creator>Wilman, Alan H</creator><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><orcidid>https://orcid.org/0000-0003-3656-0029</orcidid></search><sort><creationdate>202209</creationdate><title>Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map</title><author>Mehdizadeh, Nima ; Wilman, Alan H</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c971-412589079f7dfee06f6e525a8923a2914e3492babf299988a8d9260488582023</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2022</creationdate><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Mehdizadeh, Nima</creatorcontrib><creatorcontrib>Wilman, Alan H</creatorcontrib><collection>PubMed</collection><collection>CrossRef</collection><jtitle>Magnetic resonance in medicine</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Mehdizadeh, Nima</au><au>Wilman, Alan H</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map</atitle><jtitle>Magnetic resonance in medicine</jtitle><addtitle>Magn Reson Med</addtitle><date>2022-09</date><risdate>2022</risdate><volume>88</volume><issue>3</issue><spage>1380</spage><epage>1390</epage><pages>1380-1390</pages><issn>0740-3194</issn><eissn>1522-2594</eissn><abstract>Myelin water fraction (MWF) is often obtained from a multiple echo spin echo (MESE) sequence using multi-component T fitting with non-negative least squares. This process fits many unknowns including B to produce a T spectrum for each voxel. Presented is an alternative using a rapid B mapping sequence to supply B for the MWF fitting procedure. Effects of B errors on MWF calculations were modeled for 2D and 3D MESE using Bloch and extended phase graph simulations, respectively. Variations in SNR and relative refocusing widths were tested. Human brain experiments at 3 T used 2D MESE and an independent B map. MWF maps were produced with the standard approach and with the use of the independent B map. Differences in B and mean MWF in specific brain regions were compared. For 2D MESE, MWF with the standard method was strongly affected by B misestimations arising from limited SNR and response asymmetry around 180°, which decreased with increasing relative refocusing width. Using an independent B map increased mean MWF and decreased coefficient of variation. Notable differences in vivo in 2D MESE were in areas of high B such as thalamus and splenium where mean MWF increased by 88% and 31%, respectively (P &lt; 0.001). Simulations also demonstrated the advantages of this approach for 3D MESE when SNR is &lt;500. For 2D MESE, because of increased complexity of decay curves and limited SNR, supplying B improves MWF results in peripheral and central brain regions where flip angles differ substantially from 180°.</abstract><cop>United States</cop><pmid>35576121</pmid><doi>10.1002/mrm.29286</doi><tpages>11</tpages><orcidid>https://orcid.org/0000-0003-3656-0029</orcidid></addata></record>
fulltext fulltext
identifier ISSN: 0740-3194
ispartof Magnetic resonance in medicine, 2022-09, Vol.88 (3), p.1380-1390
issn 0740-3194
1522-2594
language eng
recordid cdi_crossref_primary_10_1002_mrm_29286
source Access via Wiley Online Library
title Myelin water fraction mapping from multiple echo spin echoes and an independent B 1 + map
url https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-12-29T06%3A34%3A31IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-pubmed_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Myelin%20water%20fraction%20mapping%20from%20multiple%20echo%20spin%20echoes%20and%20an%20independent%20B%201%20+%20map&rft.jtitle=Magnetic%20resonance%20in%20medicine&rft.au=Mehdizadeh,%20Nima&rft.date=2022-09&rft.volume=88&rft.issue=3&rft.spage=1380&rft.epage=1390&rft.pages=1380-1390&rft.issn=0740-3194&rft.eissn=1522-2594&rft_id=info:doi/10.1002/mrm.29286&rft_dat=%3Cpubmed_cross%3E35576121%3C/pubmed_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/35576121&rfr_iscdi=true