دورية أكاديمية
Retrospective image correction in the presence of nonlinear temporal magnetic field changes using multichannel navigator echoes.
العنوان: | Retrospective image correction in the presence of nonlinear temporal magnetic field changes using multichannel navigator echoes. |
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المؤلفون: | Versluis MJ; Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands. m.j.versluis@lumc.nl, Sutton BP, de Bruin PW, Börnert P, Webb AG, van Osch MJ |
المصدر: | Magnetic resonance in medicine [Magn Reson Med] 2012 Dec; Vol. 68 (6), pp. 1836-45. Date of Electronic Publication: 2012 Feb 23. |
نوع المنشور: | Journal Article; Research Support, Non-U.S. Gov't |
اللغة: | English |
بيانات الدورية: | Publisher: Wiley Country of Publication: United States NLM ID: 8505245 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1522-2594 (Electronic) Linking ISSN: 07403194 NLM ISO Abbreviation: Magn Reson Med Subsets: MEDLINE |
أسماء مطبوعة: | Publication: 1999- : New York, NY : Wiley Original Publication: San Diego : Academic Press, |
مواضيع طبية MeSH: | Algorithms* , Artifacts*, Brain/*anatomy & histology , Image Enhancement/*methods , Image Interpretation, Computer-Assisted/*methods , Magnetic Resonance Imaging/*methods, Humans ; Magnetic Fields ; Nonlinear Dynamics ; Reproducibility of Results ; Sensitivity and Specificity |
مستخلص: | Spatio-temporal magnetic field changes in the brain caused by breathing or body movements can lead to image artifacts. This is especially a problem in T(2)(*)-weighted sequences. With the acquisition of an extra echo (navigator), it is possible to measure the magnetic field change induced frequency offset for a given slice during image acquisition. However, substantial local variation across a slice can occur. This work describes an extension of the conventional navigator technique that improves the estimation of the magnetic field distribution in the brain during strong field fluctuations. This is done using the combination of signals from multiple coil elements, the coil sensitivity profiles, and frequency encoding: termed sensitivity-encoded navigator echoes. In vivo validation was performed in subjects who performed normal breathing, nose touching, and deep breathing during scanning. The sensitivity-encoded navigator technique leads to an error reduction in estimating the field distribution in the brain of 73% ± 16% compared with 56% ± 14% for conventional estimation. Image quality can be improved via incorporating this navigator information appropriately into the image reconstruction. When the sensitivity-encoded navigator technique was applied to a T(2)(*)-weighted sequence at 7 T, a ghosting reduction of 47% ± 13% was measured during nose touching experiments compared with no correction. (Copyright © 2012 Wiley Periodicals, Inc.) |
تواريخ الأحداث: | Date Created: 20120225 Date Completed: 20130529 Latest Revision: 20150525 |
رمز التحديث: | 20221213 |
DOI: | 10.1002/mrm.24202 |
PMID: | 22362637 |
قاعدة البيانات: | MEDLINE |
تدمد: | 1522-2594 |
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DOI: | 10.1002/mrm.24202 |