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Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T
Variable flip angle (VFA) sequences are a popular method of calculating T(1) values, which are required in a quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). B(1) inhomogeneities are substantial in the breast at 3 T, and these errors negatively impact the ac...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Grapho Publications, LLC
2016
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201175/ https://www.ncbi.nlm.nih.gov/pubmed/28044146 http://dx.doi.org/10.18383/j.tom.2016.00133 |
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author | Whisenant, Jennifer G. Dortch, Richard D. Grissom, William Kang, Hakmook Arlinghaus, Lori R. Yankeelov, Thomas E. |
author_facet | Whisenant, Jennifer G. Dortch, Richard D. Grissom, William Kang, Hakmook Arlinghaus, Lori R. Yankeelov, Thomas E. |
author_sort | Whisenant, Jennifer G. |
collection | PubMed |
description | Variable flip angle (VFA) sequences are a popular method of calculating T(1) values, which are required in a quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). B(1) inhomogeneities are substantial in the breast at 3 T, and these errors negatively impact the accuracy of the VFA approach, thus leading to large errors in the DCE-MRI parameters that could limit clinical adoption of the technique. This study evaluated the ability of Bloch–Siegert B(1) mapping to improve the accuracy and precision of VFA-derived T(1) measurements in the breast. Test–retest MRI sessions were performed on 16 women with no history of breast disease. T(1) was calculated using the VFA sequence, and B(1) field variations were measured using the Bloch–Siegert methodology. As a gold standard, inversion recovery (IR) measurements of T(1) were performed. Fibroglandular tissue and adipose tissue from each breast were segmented using the IR images, and the mean T(1) was calculated for each tissue. Accuracy was evaluated by percent error (%err). Reproducibility was assessed via the 95% confidence interval (CI) of the mean difference and repeatability coefficient (r). After B(1) correction, %err significantly (P < .001) decreased from 17% to 8.6%, and the 95% CI and r decreased from ±94 to ±38 milliseconds and from 276 to 111 milliseconds, respectively. Similar accuracy and reproducibility results were observed in the adipose tissue of the right breast and in both tissues of the left breast. Our data show that Bloch–Siegert B(1) mapping improves accuracy and precision of VFA-derived T(1) measurements in the breast. |
format | Online Article Text |
id | pubmed-5201175 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2016 |
publisher | Grapho Publications, LLC |
record_format | MEDLINE/PubMed |
spelling | pubmed-52011752017-12-01 Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T Whisenant, Jennifer G. Dortch, Richard D. Grissom, William Kang, Hakmook Arlinghaus, Lori R. Yankeelov, Thomas E. Tomography Research Articles Variable flip angle (VFA) sequences are a popular method of calculating T(1) values, which are required in a quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). B(1) inhomogeneities are substantial in the breast at 3 T, and these errors negatively impact the accuracy of the VFA approach, thus leading to large errors in the DCE-MRI parameters that could limit clinical adoption of the technique. This study evaluated the ability of Bloch–Siegert B(1) mapping to improve the accuracy and precision of VFA-derived T(1) measurements in the breast. Test–retest MRI sessions were performed on 16 women with no history of breast disease. T(1) was calculated using the VFA sequence, and B(1) field variations were measured using the Bloch–Siegert methodology. As a gold standard, inversion recovery (IR) measurements of T(1) were performed. Fibroglandular tissue and adipose tissue from each breast were segmented using the IR images, and the mean T(1) was calculated for each tissue. Accuracy was evaluated by percent error (%err). Reproducibility was assessed via the 95% confidence interval (CI) of the mean difference and repeatability coefficient (r). After B(1) correction, %err significantly (P < .001) decreased from 17% to 8.6%, and the 95% CI and r decreased from ±94 to ±38 milliseconds and from 276 to 111 milliseconds, respectively. Similar accuracy and reproducibility results were observed in the adipose tissue of the right breast and in both tissues of the left breast. Our data show that Bloch–Siegert B(1) mapping improves accuracy and precision of VFA-derived T(1) measurements in the breast. Grapho Publications, LLC 2016-12 /pmc/articles/PMC5201175/ /pubmed/28044146 http://dx.doi.org/10.18383/j.tom.2016.00133 Text en © 2016 The Authors. Published by Grapho Publications, LLC https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY 4.0 license (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Research Articles Whisenant, Jennifer G. Dortch, Richard D. Grissom, William Kang, Hakmook Arlinghaus, Lori R. Yankeelov, Thomas E. Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title | Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title_full | Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title_fullStr | Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title_full_unstemmed | Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title_short | Bloch–Siegert B(1)-Mapping Improves Accuracy and Precision of Longitudinal Relaxation Measurements in the Breast at 3 T |
title_sort | bloch–siegert b(1)-mapping improves accuracy and precision of longitudinal relaxation measurements in the breast at 3 t |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201175/ https://www.ncbi.nlm.nih.gov/pubmed/28044146 http://dx.doi.org/10.18383/j.tom.2016.00133 |
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