3.0T MR三维成像序列在腰骶神经根成像上的应用

Application of 3.0T MR 3D imaging sequence for displaying lumbosacral nerve root

[目的]探讨MR 3D-FIESTA序列和3D-MERGE序列在腰骶神经根成像上的可行性,比较两者所得神经根影像的优缺点。[方法]对30例正常志愿者和40例考虑腰椎间盘突出神经根受压患者分别行3D-FIESTA序列和3D-MERGE序列冠状位成像。由4名高年资医师对所得图像质量进行可视化评价,并比较两序列所得图像神经根的信噪比和对比噪声比。[结果]两序列在L_1～S_1节前神经根、神经节以及L_3～S_1节后神经根显示上基本一致,在L_1和L_2的节后神经根显示上3D-FIESTA序列不及3D-MERGE序列。尽管3D-FIESTA序列对正常神经根显示评分优于3D-MERGE序列[(3.72±0.28) vs (3.36±0.31),P<0.05),前一序列对受压神经根的显示评分不及后一序列[(2.26±0.57) vs (2.81±0.42),P<0.05)。对神经根的SNR及神经根与椎体CNR的比较,3D-FIESTA序列为(48.37±9.29)、(33.25±15.46),而3D-MERGE序列分别为(122.19±15.54)、(83.92±20.47),前者不及后者(P<0.05)。然而,在神经根与脑脊液的CNR方面, 3D-FIESTA序列显著优于3D-MERGE序列[(230.57±65.02) vs(81.94±20.96),P<0.05]。[结论] 3D-FIESTA序列与3D-MERGE序列均可良好显示腰骶神经根:3D-FIESTA序列适合于显示椎管内节前神经根;3D-MERGE序列则可更好的显示侧隐窝段及远端神经根和受压的神经根。

[Objective]To explore the feasibility of MR 3D-FIESTA sequence and 3D-MERGE sequence for displaying lumbosacral nerve root,and compare the advantages and disadvantages of the two sequences.[Methods]A total of 30 normal volunteers and 40 patients with lumbar intervertebral disc herniation were checked with 3D-FIESTA sequence and 3DMERGE sequence coronal imaging.The image quality was visualized by four senior doctors,and the signal to noise ratio(SNR)and the carrier to noise ratio(CNR)were compared between the two sequences.[Results]Although the two sequences proved consistent in showing the L1~S1 preganglionic nerve root,ganglion and L3~S1 posterior nerve root,the 3D-FIESTA sequences was inferior to 3D-EMRGE sequence in displaying the L1 and L2 posterior nerve root.For showing the normal nerve root the 3DFIESTA sequence had significantly higher image quality score than the 3D-MERGE sequence[(3.72±0.28)versus(3.36±0.31),P<0.05],conversely,the former got significantly lowere score than the latter for presenting the compression of nerve root((2.26±0.57)versus(2.81±0.42),P<0.05)In term of nerve root SNR,as well as CNR between nerve root and vertebral body,the 3DFIESTA sequence was of(48.37±9.29)and(33.25±15.46),while the 3D-MERGE sequence was of(122.19±15.54)and(83.92±20.47)respectively,the former were significantly inferior to the latter(P<0.05).However,the 3D-FIESTA sequence proved significantly superior to the 3D-MERGE sequence regarding CNR between nerve root and cerebrospinal fluid((230.57±65.02)versus(81.94±20.96),P<0.05)[Conclusion]Both 3D-FIESTA sequence and 3D-MERGE sequence are feasible for presenting lumbar sacral nerve.The 3D-FIESTA sequence is suitable to show the preganglionic nerve in the spinal canal,while 3D-MERGE sequence is more useful to displaying lateral recess segment and distal nerve root,and the compressed nerve root.