7 T renal MRI: challenges and promises

MAGMA. 2016 Jun;29(3):417-33. doi: 10.1007/s10334-016-0538-3. Epub 2016 Mar 23.

Abstract

The progression to 7 Tesla (7 T) magnetic resonance imaging (MRI) yields promises of substantial increase in signal-to-noise (SNR) ratio. This increase can be traded off to increase image spatial resolution or to decrease acquisition time. However, renal 7 T MRI remains challenging due to inhomogeneity of the radiofrequency field and due to specific absorption rate (SAR) constraints. A number of studies has been published in the field of renal 7 T imaging. While the focus initially was on anatomic imaging and renal MR angiography, later studies have explored renal functional imaging. Although anatomic imaging remains somewhat limited by inhomogeneous excitation and SAR constraints, functional imaging results are promising. The increased SNR at 7 T has been particularly advantageous for blood oxygen level-dependent and arterial spin labelling MRI, as well as sodium MR imaging, thanks to changes in field-strength-dependent magnetic properties. Here, we provide an overview of the currently available literature on renal 7 T MRI. In addition, we provide a brief overview of challenges and opportunities in renal 7 T MR imaging.

Keywords: 7 T MRI; Kidney; RF shimming; Renal MRI.

Publication types

  • Review

MeSH terms

  • Animals
  • Humans
  • Image Enhancement / methods
  • Kidney / diagnostic imaging*
  • Kidney / pathology
  • Magnetic Resonance Angiography*
  • Magnetic Resonance Imaging*
  • Nephrons / diagnostic imaging
  • Nephrons / pathology
  • Oxygen / blood
  • Oxygen / chemistry
  • Reproducibility of Results
  • Signal-To-Noise Ratio
  • Spin Labels

Substances

  • Spin Labels
  • Oxygen