TrueBOLD: Detection of brain activity with TrueFISP

• Applicant: Professor Klaus Scheffler, Ph.D.
• Subject Area: Medical Physics, Biomedical Technology
• Term: from 2017 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 320973753

• Final Report Year: 2025

Final Report Abstract

TrueBOLD addresses the detection of neuronal activity in humans with magnetic resonance imaging based on balanced SSFP acquisition scheme at very high fields. Traditionally, blood oxygenation changes are detected with T2*-weighted echo planar sequences (EPI) that are sensitive to the static dephasing around small and larger vessels filled with deoxygenated blood. EPI is not specific to a certain type of vessel architecture or size, it sometimes shows blurring and blooming around larger vessels, it shows significant spatial distortions and thus severe challenges in precise co-registration to submillimeter anatomical scans. The proposed detection of BOLD changes with pass-band balanced SSFP, TrueBOLD has the potential to overcome these limitations. We addressed a number of challenges and research questions that are linked to the fast and reliable implementation of balanced SSFP at 9.4T. One major outcome of this project was the demonstration of the very specific sensitivity of TrueBOLD to small cortical vessels enabling corticallaminar specific functional imaging without the bias from larger draining veins. We also have shown that laminar-specific functional imaging with TrueBOLD has a superior signal fidelity and signal-to-noise ration to existing techniques.

Publications

• Multiline balanced SSFP for rapid functional imaging at ultrahigh field. Magnetic Resonance in Medicine, 79(2), 994-1000.
  Ehses, Philipp & Scheffler, Klaus
  
• The impact of vessel size, orientation and intravascular contribution on the neurovascular fingerprint of BOLD bSSFP fMRI. NeuroImage, 163, 13-23.
  Báez-Yánez, Mario Gilberto; Ehses, Philipp; Mirkes, Christian; Tsai, Philbert S.; Kleinfeld, David & Scheffler, Klaus
  
• Autofocusing‐based phase correction. Magnetic Resonance in Medicine, 80(3), 958-968.
  Loktyushin, Alexander; Ehses, Philipp; Schölkopf, Bernhard & Scheffler, Klaus
  
• The BOLD sensitivity of rapid steady‐state sequences. Magnetic Resonance in Medicine, 81(4), 2526-2535.
  Scheffler, Klaus; Heule, Rahel; Báez‐Yánez, Mario G.; Kardatzki, Bernd & Lohmann, Gabriele
  
• A 32‐channel multi‐coil setup optimized for human brain shimming at 9.4T. Magnetic Resonance in Medicine, 83(2), 749-764.
  Aghaeifar, Ali; Zhou, Jiazheng; Heule, Rahel; Tabibian, Behzad; Schölkopf, Bernhard; Jia, Feng; Zaitsev, Maxim & Scheffler, Klaus
  
• Impact of prospective motion correction, distortion correction methods and large vein bias on the spatial accuracy of cortical laminar fMRI at 9.4 Tesla. NeuroImage, 208, 116434.
  Bause, Jonas; Polimeni, Jonathan R.; Stelzer, Johannes; In, Myung-Ho; Ehses, Philipp; Kraemer-Fernandez, Pablo; Aghaeifar, Ali; Lacosse, Eric; Pohmann, Rolf & Scheffler, Klaus
  
• Intravascular BOLD signal characterization of balanced SSFP experiments in human blood at high to ultrahigh fields. Magnetic Resonance in Medicine, 85(4), 2055-2068.
  Pérez‐Rodas, Marlon; Pohmann, Rolf; Scheffler, Klaus & Heule, Rahel
  
• Multi‐parametric artificial neural network fitting of phase‐cycled balanced steady‐state free precession data. Magnetic Resonance in Medicine, 84(6), 2981-2993.
  Heule, Rahel; Bause, Jonas; Pusterla, Orso & Scheffler, Klaus
  
• BOLD sensitivity and vessel size specificity along CPMG and GRASE echo trains. Magnetic Resonance in Medicine, 86(4), 2076-2083.
  Scheffler, Klaus; Engelmann, Jörn & Heule, Rahel
  
• High‐resolution neural network‐driven mapping of multiple diffusion metrics leveraging asymmetries in the balanced steady‐state free precession frequency profile. NMR in Biomedicine, 35(6).
  Birk, Florian; Glang, Felix; Loktyushin, Alexander; Birkl, Christoph; Ehses, Philipp; Scheffler, Klaus & Heule, Rahel
  
• Unshielded bent folded‐end dipole 9.4 T human head transceiver array decoupled using modified passive dipoles. Magnetic Resonance in Medicine, 86(1), 581-597.
  Avdievich, Nikolai I.; Solomakha, Georgiy; Ruhm, Loreen; Henning, Anke & Scheffler, Klaus
  
• Accelerated MRI at 9.4 T with electronically modulated time‐varying receive sensitivities. Magnetic Resonance in Medicine, 88(2), 742-756.
  Glang, Felix; Nikulin, Anton V.; Bause, Jonas; Heule, Rahel; Steffen, Theodor; Avdievich, Nikolai & Scheffler, Klaus
  
• MAGNETIC RESONANCE TOMOGRAPHY (MRT) IMAGING, EMPLOYING RF RECEIVE COILS WITH TEMPORAL SENSITIVITY PROFILE MODULATION. Patent number: 11378634 Type: Grant, Filed: August 4, 2020, Date of Patent: July 5, 2022 Assignee: Max-Planck-Gesellschaft zur Foerderung der Wissenschaften e. V.
  Klaus Scheffler; Jonas Bause; Alexander Loktyushin & Kai Buckenmaier
  
• Optimized ultrahigh field parallel transmission workflow using rapid presaturated TurboFLASH transmit field mapping with a three‐dimensional centric single‐shot readout. Magnetic Resonance in Medicine, 89(1), 322-330.
  Bosch, Dario; Bause, Jonas; Geldschläger, Ole & Scheffler, Klaus
  
• FastPtx: a versatile toolbox for rapid, joint design of pTx RF and gradient pulses using Pytorch’s autodifferentiation. Magnetic Resonance Materials in Physics, Biology and Medicine, 37(1), 127-138.
  Bosch, Dario & Scheffler, Klaus
  
• Functional mapping of sensorimotor activation in the human thalamus at 9.4 Tesla. Frontiers in Neuroscience, 17.
  Charyasz, Edyta; Heule, Rahel; Molla, Francesko; Erb, Michael; Kumar, Vinod Jangir; Grodd, Wolfgang; Scheffler, Klaus & Bause, Jonas
  
• Prediction of motion induced magnetic fields for human brain MRI at 3 T. Magnetic Resonance Materials in Physics, Biology and Medicine, 36(5), 797-813.
  Zhou, Jiazheng; Hagberg, Gisela E.; Aghaeifar, Ali; Bause, Jonas; Zaitsev, Maxim & Scheffler, Klaus
  
• Reconfigurable dipole receive array for dynamic parallel imaging at ultra‐high magnetic field. Magnetic Resonance in Medicine, 90(4), 1713-1727.
  Nikulin, Anton V.; Glang, Felix; Avdievich, Nikolai I.; Bosch, Dario; Steffen, Theodor & Scheffler, Klaus
  
• Intra‐scan RF power amplifier drift correction. Magnetic Resonance in Medicine, 92(2), 645-659.
  Aghaeifar, Ali; Bosch, Dario; Heule, Rahel; Williams, Sydney; Ehses, Philipp; Mauconduit, Franck & Scheffler, Klaus
  
• Submillimeter balanced SSFP BOLD–functional MRI accelerated with 3D stack‐of‐spirals at 9.4 T. Magnetic Resonance in Medicine, 92(1), 186-201.
  Iyyappan, Valsala Praveen; Veldmann, Marten; Bosch, Dario; Scheffler, Klaus & Ehses, Philipp
  
• Macrovascular contributions to resting-state fMRI signals: A comparison between EPI and bSSFP at 9.4 Tesla. Imaging Neuroscience, 3.
  Ramadan, Dana; Mueller, Sebastian; Stirnberg, Ruediger; Bosch, Dario; Ehses, Philipp; Scheffler, Klaus & Bause, Jonas