Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstr. 55, Essen, Germany.
Eur Radiol. 2011 Apr;21(4):841-9. doi: 10.1007/s00330-010-1962-9. Epub 2010 Sep 25.
To investigate the feasibility of 7T MR imaging of the kidneys utilising a custom-built 8-channel transmit/receive radiofrequency body coil.
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.
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.
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.
利用定制的 8 通道发射/接收射频体线圈，研究在 7T 磁共振成像（MRI）中对肾脏进行成像的可行性。
在 7T 全身磁共振系统上对 8 名健康志愿者进行了未增强的活体 MRI 检查。在进行 B0 匀场后，获得了以下序列：1）二维和三维扰相梯度回波序列（FLASH、VIBE）；2）二维 T1 加权同相位和反相位；3）True-FISP 成像；4）T2 加权涡轮自旋回波（TSE）序列。两名放射科医生对整体图像质量进行了视觉评估。
在所有 8 名受试者中，7T 肾脏 MRI 是可行的。使用 T1 加权梯度回波 MRI 可获得最佳图像质量，提供了高解剖细节和出色的非增强血管对比度。通过成功的匀场，可以有效减少 B1 信号空洞，并在大多数序列类型中将其移出感兴趣区域。然而，由于在 3 名志愿者中存在信号不均匀性，T2 加权 TSE 成像仍然具有挑战性，并且受到严重影响。
这些结果证明了专用 7T 肾脏成像的可行性和诊断潜力。进一步优化成像序列和专用射频线圈概念有望提高采集质量，并最终提供高临床诊断价值。
