兔坐骨神经背景信号抑制扩散加权成像

Diffusion weighted whole body imaging with background signal suppression (DWIBS) in peripheral nerve:animal experiment study

目的探讨DWIBS周围神经成像扫描参数的优化方案。方法对5只健康新西兰白兔行坐骨神经冠状位MRN成像,评价不同参数组合DWIBS序列及T2WI/SPIR图像兔坐骨神经的显示效果以及图像信号噪声比(SNR)与对比噪声比(CNR)。制作兔坐骨神经组织切片。结果T2WI/SPIR图像和b值=200 s/mm^2、层厚=2 mm的DWIBS序列兔坐骨神经成像效果较好。T2WI/SPIR图像SNR和CNR最高。DWIBS中,以b值=200 s/mm^2、层厚=1.5 mm序列SNR、CNR最高。结论采用适当b值(200 s/mm^2)和薄层扫描(1.5 mm)能够获得较好的兔坐骨神经DWIBS图像。

Objective To discuss DWIBS imaging protocols of peripheral nerve imaging. Methods MRN imaging of each sciatic nerve were obtained coronally in 5 adult New Zealand white rabbits. All images of rabbit sciatic nerve in DWIBS and T2WI/SPIR were observed, and the imaging qualities were evaluated by measurement the signal intensity of middle segment of sciatic nerve （SN）, muscle （SM） and background （SD）, also calculating signal-noise ratio （SNR） and contrast-noise ratio （CNR） of each sequence. Results The rabbit sciatic nerve was showed with high signal, especially on DWIBS （with b value =200 s/mm^2, slice thickness= 2 mm） and T2WI/SPIR. Among all images, T2WI/SPIR got the highest SNR and CNR. SNR and CNR of DWIBS with b value= 200 s/mm^2 , slice thickness = 2 mm was higher than those of other DWIBS sequences. Conclusion Preferable rabbit sciatic nerve DWIBS could be obtained with higher SNR and CNR by adopting b value （200 s/mm^2） and smaller slice thickness. Histopathologic factors impacted DWIBS neuroimaging.