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High resolution single-shot EPI at 7T

  • Research Article
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Magnetic Resonance Materials in Physics, Biology and Medicine Aims and scope Submit manuscript

Abstract

Objective

Single-shot echo planar imaging (EPI) acquisitions at 7T are challenging due to increased distortions, signal dropouts, RF-power requirements, and reduced T2*. This study developed and tested pulse sequence and protocol modifications required to allow high resolution EPI for whole brain functional neuroimaging.

Materials and methods

Using geometric distortion correction methods, modified fat saturation, and parallel imaging, we acquired high resolution single-shot gradient-echo EPI data at 7T with different spatial resolution. The BOLD sensitivity was evaluated and quantified in a breath hold experiment.

Results

Single-shot EPI data with isotropic resolution from 3 to 1.1 mm were acquired in human subjects. The RF-power deposition has been reduced to allow up to 22 slices per second. In addition, acoustic noise and helium boil-off have been reduced. A reduction of the fat saturation flip angle resulted in up to 20% signal gain without compromising the fat suppression quality. For the coil used, the BOLD sensitivity is highest for 2 or 1.4 mm isotropic resolution.

Conclusion

High resolution single-shot EPI in the whole brain can be performed at 7T with high efficiency, low signal dropout, and without major geometric distortions.

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Authors and Affiliations

  1. Department of Biomedical Magnetic Resonance, Faculty of Natural Sciences/Institute for Experimental Physics, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, Haus 01, 39120, Magdeburg, Germany

    Oliver Speck

  2. Leibniz Institute for Neurobiology, Magdeburg, Germany

    J. Stadler

  3. Medical Physics, Department of Diagnostic Radiology, University Hospital Freiburg, Freiburg, Germany

    M. Zaitsev

Authors
  1. Oliver Speck
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  2. J. Stadler
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  3. M. Zaitsev
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Correspondence to Oliver Speck.

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Speck, O., Stadler, J. & Zaitsev, M. High resolution single-shot EPI at 7T. Magn Reson Mater Phy 21, 73 (2008). https://doi.org/10.1007/s10334-007-0087-x

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  • DOI: https://doi.org/10.1007/s10334-007-0087-x

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