A Modular Hybrid Framework for CEST MRI Development and Clinical Translation Using pTx-Pulseq Preparation With Open- and Closed-Source Readouts and ONNX Mapping
Freudensprung M, Rajput JR, Liebig P, Weinmüller S, Singer L, Vladimirov N, Perlman O, Nagel AM, Dörfler A, Zaiß M (2026)
Publication Type: Journal article
Publication year: 2026
Journal
DOI: 10.1002/mrm.70596
Abstract
Purpose: Chemical exchange saturation transfer (CEST) MRI offers unique metabolic insights for imaging of cancer, stroke, or neurodegeneration. However, the rapid expansion of CEST preparation schemes and evaluation techniques creates a bottleneck; novel methods often remain complex prototypes requiring offline processing, preventing clinical adoption. Methods: To bridge this gap, we propose a hybrid sequence and reconstruction framework. This approach combines a flexible, pTx-enabled preparation block using the open-source Pulseq standard with a closed-source snapshot readout, and an interchangeable ONNX-based neural network for online post-processing. Results: We validated this framework at 7 T using three distinct applications: deepWASABI for B0 and B1 prediction, a protein CEST approach for B1-corrected CEST mapping, and semi-solid MT MRF for quantifying magnetization transfer rates and semi-solid proton volume fractions. By utilizing closed-source readouts, we leverage advanced proprietary image reconstructions essential for high-resolution whole-brain coverage. Simultaneously, the integrated ONNX network processes contrast-weighted images directly at the scanner to generate parameter maps online. Conclusion: This hybrid architecture eliminates complex compilation steps, allowing deployment by simply copying Pulseq and ONNX files. By enabling push-button execution and immediate clinical data storage, this platform significantly accelerates the development, evaluation, and dissemination of advanced CEST MRI methods and forms a blueprint for scaling any magnetization-prepared MRI approach at any system.
Authors with CRIS profile
Martin Freudensprung
Neuroradiologisches Institut
Simon Weinmüller
Department of Neuroradiology
Ludwig Singer
Neuroradiologisches Institut
Armin Michael Nagel
Institute of Radiology
Arnd Dörfler
Department of Neuroradiology
Moritz Zaiß
Professur für Multimodale Bildgebung in der klinischen Forschung
Involved external institutions
Israel (IL)How to cite
APA:
Freudensprung, M., Rajput, J.R., Liebig, P., Weinmüller, S., Singer, L., Vladimirov, N.,... Zaiß, M. (2026). A Modular Hybrid Framework for CEST MRI Development and Clinical Translation Using pTx-Pulseq Preparation With Open- and Closed-Source Readouts and ONNX Mapping. Magnetic Resonance in Medicine. https://doi.org/10.1002/mrm.70596
MLA:
Freudensprung, Martin, et al. "A Modular Hybrid Framework for CEST MRI Development and Clinical Translation Using pTx-Pulseq Preparation With Open- and Closed-Source Readouts and ONNX Mapping." Magnetic Resonance in Medicine (2026).
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