Work

Optimal MR-ARFI encoding parameters for a range of contemporary magnetic field gradient systems

Year: 2026

Type: preprint

Abstract: Purpose To optimize motion encoding gradients in MR-Acoustic Radiation Force Imaging (ARFI) experiments under a range of experimental conditions, and to provide a general simulation tool. Methods In MR-ARFI, Transcranial focused Ultrasound Stimulation (TUS) induced tissue displacement is encoded by motion encoding gradients as a phase change. We extended previously proposed equations for phase SNR to account for finite gradient switching times. We simulated the phase SNR while varying the strength and slew rate of motion encoding gradients for monopolar and bipolar encoding schemes in order to identify optimal configurations for various gradient hardware specifications. Phantom MR-ARFI experiments were performed to validate the simulations. Results Optimized gradient durations are derived for a range of gradient strengths and slew rates. Gradient slew-rate is shown to influence the optimal parameters. Phantom MR-ARFI results showed good agreement with the simulations. Conclusion The availability of modern gradient hardware is shown to dramatically improve the sensitivity of the ARFI experiment. Our openly available calculation tool allows ready calculation of optimal timings for any experimental conditions.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.10.13.758785

Authors: Shota Hodono, David G. Norris

Institutions: Radboud University Nijmegen, Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Twente

Language: English

Topic: Advanced MRI Techniques and Applications

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

Open Access status: green

Funders: European Commission, Radboud Universiteit, HORIZON EUROPE Framework Programme

Award: G3763542640