Renal imaging at 7 Tesla: preliminary results.
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.
Umutlu
Lale
L
Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstr. 55, Essen, Germany. Lale.Umutlu@uk-essen.de
Orzada
Stephan
S
Kinner
Sonja
S
Maderwald
Stefan
S
Brote
Irina
I
Bitz
Andreas K
AK
Kraff
Oliver
O
Ladd
Susanne C
SC
Antoch
Gerald
G
Ladd
Mark E
ME
Quick
Harald H
HH
Lauenstein
Thomas C
TC
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