TY  - JOUR
A1  - Umutlu, Lale
A1  - Orzada, Stephan
A1  - Kinner, Sonja
A1  - Maderwald, Stefan
A1  - Bronte, Irina
A1  - Bitz, Andreas
A1  - Kraff, Oliver
A1  - Ladd, Susanne C.
A1  - Antoch, Gerald
A1  - Ladd, Mark E.
A1  - Quick, Harald H.
A1  - Lauenstein, Thomas C.
T1  - Renal imaging at 7 Tesla: preliminary results
JF  - European Radiology
N2  - 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 B0 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, B1 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.

Conclusion
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.
Y1  - 2011
SN  - 1432-1084
VL  - 21
IS  - 4
SP  - 841
EP  - 849
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Umutlu, Lale
A1  - Kraff, Oliver
A1  - Fischer, Anja
A1  - Kinner, Sonja
A1  - Maderwald, Stefan
A1  - Nassenstein, Kai
A1  - Nensa, Felix
A1  - Grüneisen, Johannes
A1  - Orzada, Stephan
A1  - Bitz, Andreas
A1  - Forsting, Michael
A1  - Ladd, Mark E.
A1  - Lauenstein, Thomas C.
T1  - Seven-Tesla MRI of the female pelvis
JF  - European Radiology
Y1  - 2013
U6  - http://dx.doi.org/10.1007/s00330-013-2868-0
SN  - 1432-1084
VL  - 23
IS  - 9
SP  - 2364
EP  - 2373
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Maas, Marnix C.
A1  - Vos, Eline K.
A1  - Lagemaat, Miriam W.
A1  - Bitz, Andreas
A1  - Orzada, Stephan
A1  - Kobus, Thiele
A1  - Kraff, Oliver
A1  - Maderwald, Stefan
A1  - Ladd, Mark E.
A1  - Scheenen, Tom W. J.
T1  - Feasibility of T₂-weighted turbo spin echo imaging of the human prostate at 7 tesla
JF  - Magnetic Resonance in Medicine
N2  - Purpose
To demonstrate that high quality T₂-weighted (T2w) turbo spin-echo (TSE) imaging of the complete prostate can be achieved routinely and within safety limits at 7 T, using an external transceive body array coil only.

Methods
Nine healthy volunteers and 12 prostate cancer patients were scanned on a 7 T whole-body system. Preparation consisted of B₀ and radiofrequency shimming and localized flip angle calibration. T₁ and T₂ relaxation times were measured and used to define the T2w-TSE protocol. T2w imaging was performed using a TSE sequence (pulse repetition time/echo time 3000–3640/71 ms) with prolonged excitation and refocusing pulses to reduce specific absorption rate.

Results
High quality T2w TSE imaging was performed in less than 2 min in all subjects. Tumors of patients with gold-standard tumor localization (MR-guided biopsy or prostatectomy) were well visualized on 7 T imaging (n = 3). The number of consecutive slices achievable within a 10-g averaged specific absorption rate limit of 10 W/kg was ≥28 in all subjects, sufficient for full prostate coverage with 3-mm slices in at least one direction.

Conclusion
High quality T2w TSE prostate imaging can be performed routinely and within specific absorption rate limits at 7 T with an external transceive body array.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/mrm.24818
SN  - 1522-2594
VL  - 71
IS  - 5
SP  - 1711
EP  - 1719
PB  - Wiley-VCH
CY  - Weinheim
ER  -