Ready for Routine: Homogeneous, High-Resolution, and Multicontrast Whole-Brain MRI at 7 Tesla in Short Scan Time With "plug-and-Play" pTx Sequences. - 2025
InvestigativeRadiology_61(6)_(2026-Jun)_[Faber]—Ready for Routine--Homogeneous, High-Resolution, and Multicontrast Whole-Brain MRI at 7 Tesla in Short Scan Time With “Plug-and-Play” pTx Sequences.pdf
[en] [en] BACKGROUND: 7T MRI received FDA/CE clearance almost 7 years ago. However, until today, it has not yet been widely adopted in clinical routine. This is mainly due to field inhomogeneities that impede whole-brain coverage. Moreover, the long scan times often associated with high-resolution imaging are an additional limiting factor.
PURPOSE: To combine calibration-free parallel transmit technology (pTx) using universal pulses (UP) with advanced imaging acceleration strategies to achieve homogenous multicontrast 7T MRI with whole-brain coverage and high spatial resolution in short scan time.
MATERIALS AND METHODS: Ten healthy volunteers were scanned both with conventional vendor-provided sequences and with custom sequences for anatomical whole-brain imaging [-weighted, -weighted, FLAIR, and susceptibility-weighted]. The scan times for the 2 anatomical protocols were matched (25 minutes). In addition, a quantitative MRI protocol [multi-parametric mapping (MPM) and chemical exchange saturation transfer (CEST)] was scanned twice using custom sequences with conventional (circular polarized) and UPs, respectively, in a scan time of 2×25 minutes. Moreover, 4 patients with different neurological diseases were scanned, namely temporal lobe epilepsy, spinocerebellar ataxia, cerebral amyloid angiopathy, and glioblastoma. For the patients, only optimized custom sequences with UPs were acquired.
RESULTS: Compared with conventional implementations, the custom sequences provide strongly improved image homogeneity and quality with significantly higher SNR and CNR across the whole brain, including cerebellum and brain stem. Moreover, UPs improve the repeatability of derived quantitative parameters. The suggested protocol has additionally been successfully demonstrated in 4 patients with different neurological pathologies.
CONCLUSIONS: Homogeneous whole-brain 7T MRI with high spatial resolution and high image quality is possible in clinically feasible scan times. The developed protocol can be applied without any expert knowledge and is ready for clinical use. The approach could largely extend applicability of UHF MRI in neuroradiology paving the way for increased routine use of 7T MRI.
Disciplines :
Radiology, nuclear medicine & imaging
Author, co-author :
Faber, Jennifer
Paech, Daniel
Pracht, Eberhard
Stirnberg, Rüdiger
Ehses, Philipp
Völzke, Yannik
Löwen, Daniel
Ferreira, Mónica
Brunheim, Sascha
Boulant, Nicolas
Gras, Vincent
Mauconduit, Franck
Massire, Aurélien
Goa, Pål Erik
Lamalle, Laurent ; Université de Liège - ULiège > Département de physique
This work received financial support through the German Federal Ministry of Education and Research (BMBF; funding code 01ED2109A) and the Research Council of Norway (RCN, funding code 322980), both as part of the SCAIFIELD project under the aegis of the EU Joint Programme\u2014Neurodegenerative Disease Research (JPND) and from the European Union Horizon 2020 Research and Innovation program under grant agreement 885876 (AROMA). D.P. has received funding from the Else Kroener Fresenius Foundation (2022_EKES.33). J.F. was funded within the Advanced Clinician Scientist Programme (ACCENT, funding code 01EO2107, by the German Federal Ministry of Education and Research (BMBF) and as a PI of the iBehave Network, sponsored by the Ministry of Culture and Science of the State of North Rhine-Westphalia and received funding from the National Ataxia Foundation (NAF). J.F. is members of the European Reference Network for Rare Neurological Diseases. T.B. was funded by the Neuro-aCSis Bonn Neuroscience Clinician Scientist Program (2024-12-07).Bundesministerium f\u00FCr Bildung, Wissenschaft, Forschung und Technologie, http://dx.doi.org/10.13039/501100010571, German Federal Ministry of Education and Research (BMBF; funding code 01ED2109A), T.S., Bundesministerium f\u00FCr Bildung und Forschung, http://dx.doi.org/10.13039/501100002347, German Federal Ministry of Education and Research (BMBF; funding code 01ED2109A), T.K., Horizon 2020 Framework Programme, http://dx.doi.org/10.13039/100010661, European Union Horizon 2020 Research and Innovation program under grant agreement 885876 (AROMA)., T.S.
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