| Zugriffsnummer | 52302 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Accelerated B1+ mapping and robust parallel transmit pulse design for heart and prostate imaging at 7 T |
| Autor(in); Institution |
Egger, Nico; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
Nagelstraßer, Sophia; Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
Wildenberg, Saskia; Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
Bitz, Andreas; Electrical Engineering and Information Technology, University of Applied Sciences - FH Aachen, Aachen, GERMANY
Ruck, Laurent; Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
Herrler, Jürgen; Siemens Healthcare, Erlangen, Bavaria, GERMANY
Meixner, Christian Rainer; Siemens Healthcare, Erlangen, Bavaria, GERMANY
Kimmlingen, Ralph; Siemens Healthcare, Erlangen, Bavaria, GERMANY
Lanz, Titus; Rapid Biomedical, Rimpar, GERMANY
Uder, Michael; Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
Nagel, Armin Michael; Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, GERMANY
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| Quelle/Jahr | Magnetic Resonance in Medicine: 92 (2024), 5, 1933 - 1951 |
| ISSN | 0740-3194 (print) ; 1522-2594 (online) |
| DOI | |
| Verlag | New York, NY: Wiley |
| Freie Schlagworte | 7 Tesla ; B+1 mapping ; heart ; parallel transmission ; prostate ; ultra high-field |
| Zusammenfassung | Purpose To investigate the impact of reduced k-space sampling on B+1 mapping and the resulting impact on phase shimming and dynamic/universal parallel transmit (pTx) RF pulse design. Methods Channel-wise 3D B+1 maps were measured at 7 T in 35 and 23 healthy subjects for the heart and prostate region, respectively. With these B+1 maps, universal phase shims optimizing homogeneity and B+1 efficiency were designed for heart and prostate imaging. In addition, universal 4kT-point pulses were designed for the heart. Subsequently, individual phase shims and individual 4kT-pulses were designed based on B+1 maps with different acceleration factors and tested on the original maps. The performance of the pulses was compared by evaluating their coefficients of variation (CoV), B+1 efficiencies and specific energy doses (SED). Furthermore, validation measurements were carried out for one heart and one prostate subject. Results For both organs, the universal phase shims showed significantly higher B+1 efficiencies and lower CoVs compared to the vendor provided default shim, but could still be improved with individual phase shims based on accelerated maps (acquisition time = 30 s). In the heart, the universal 4kT-pulse achieved significantly lower CoVs than tailored phase shims. Tailored 4kT-pulses based on accelerated B+1 maps resulted in even further reduced CoVs or a 2.5-fold reduction in SED at the same CoVs as the universal 4kT-pulse. Conclusion Accelerated B+1maps can be used for the design of tailored pTx pulses for prostate and cardiac imaging at 7 T, which further improve homogeneity, B+1 efficiency, or SED compared to universal pulses. |
| Kostenfreier Zugang | Open Access Hybrid |
| Rechteinformation | CC BY 4.0 ; Creative Commons Attribution 4.0 License |
| Förderinformationen (1) | Förderername: Open Access funding enabled and organized by Projekt DEAL |
Zitierung
Egger, N., Nagelstraßer, S., Wildenberg, S., Bitz, A., Ruck, L., Herrler, J., Meixner, C. R., Kimmlingen, R., Lanz, T., Schmitter, S., Uder, M., & Nagel, A. M. (2024). Accelerated B1+ mapping and robust parallel transmit pulse design for heart and prostate imaging at 7 T. Magnetic Resonance in Medicine, 92(5), 1933–1951. https://doi.org/10.1002/mrm.30185