title: Renal imaging at 7 Tesla: preliminary results.
abstract: OBJECTIVE
  To investigate the feasibility of 7T MR imaging of the kidneys utilising a custom-built 8-channel transmit/receive radiofrequency body coil.
  
  
  METHODS
  In vivo unenhanced MR was performed in 8 healthy volunteers on a 7T whole-body MR system. After B(0) shimming the following sequences were obtained: 1) 2D and 3D spoiled gradient-echo sequences (FLASH, VIBE), 2) T1-weighted 2D in and opposed phase 3) True-FISP imaging and 4) a T2-weighted turbo spin echo (TSE) sequence. Visual evaluation of the overall image quality was performed by two radiologists.
  
  
  RESULTS
  Renal MRI at 7T was feasible in all eight subjects. Best image quality was found using T1-weighted gradient echo MRI, providing high anatomical details and excellent conspicuity of the non-enhanced vasculature. With successful shimming, B(1) signal voids could be effectively reduced and/or shifted out of the region of interest in most sequence types. However, T2-weighted TSE imaging remained challenging and strongly impaired because of signal heterogeneities in three volunteers.
  
  
  CONCLUSIONS
  The results demonstrate the feasibility and diagnostic potential of dedicated 7T renal imaging. Further optimisation of imaging sequences and dedicated RF coil concepts are expected to improve the acquisition quality and ultimately provide high clinical diagnostic value.
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstr. 55, Essen, Germany. Lale.Umutlu@uk-essen.de
authors.forename: Lale
authors.initials: L
authors.lastname: Umutlu
authors.forename: Stephan
authors.initials: S
authors.lastname: Orzada
authors.forename: Sonja
authors.initials: S
authors.lastname: Kinner
authors.forename: Stefan
authors.initials: S
authors.lastname: Maderwald
authors.forename: Irina
authors.initials: I
authors.lastname: Brote
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Bitz
authors.forename: Oliver
authors.initials: O
authors.lastname: Kraff
authors.forename: Susanne C
authors.initials: SC
authors.lastname: Ladd
authors.forename: Gerald
authors.initials: G
authors.lastname: Antoch
authors.forename: Mark E
authors.initials: ME
authors.lastname: Ladd
authors.forename: Harald H
authors.initials: HH
authors.lastname: Quick
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Lauenstein
mesh_terms: D000328:Adult; D003952:Diagnostic Imaging / Q000379:methods; D004867:Equipment Design; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015233:Models, Statistical; D011846:Radio Waves; D011871:Radiology / Q000379:methods*; D012815:Signal Processing, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000379:methods