正常成人腰神经根解剖结构的MR研究

Study on Anatomical Structure of the Normal Human Lumbar Nerve Root with MR

目的：利用选择性激励（PROSET）成像观察正常成人腰神经根及其毗邻结构的在体磁共振特点。方法：对40例中国正常成人志愿者行腰椎PROSET扫描，测量神经根直径（RD）、根囊角（RA）、神经根出硬膜囊的位置到椎弓根下缘的距离（RPD）、神经根上缘与上位椎弓根下缘距离（PSRD）、神经根下缘与下位椎弓根上缘的距离（PIRD）、椎弓根间距（IPD）、椎弓根高度（PH）、椎弓根宽度（PW）等指标。用SPSS11．5软件统计分析。结果：RD、RA、RPD、PIRD、IPD、PH、PW在L1～L5之间差异有统计学意义（P〈0．05），由上至下RD、RPD、PW、IPD逐渐增大，RA、PH、PSRD逐渐减小；L1、3节段IPD和L1、4节段PW男女之间差异有统计意义（P〈0．05），且男性大于女性。结论：磁共振PROSET成像能无创、准确、全面提供活体腰神经根及其毗邻结构的形态学特点。

Purpose： To investigate the characteristic of the normal lumbar nerve root and its relationship with surrounding structures by MR principle of selective excitation technique （PROSET）. Methods： MR PROSET sequence was used to study the lumbar nerve roots in 40 healthy volunteers （21 males and 19 females） with age ranged from 25 to 35 years old. Nerve root diameter （RD）, root exit angle （RA）, nerve root outlet-inferior pedicles distance （RPD）, pedicle-superior nerve root distance （PSRD）, pedicle- inferior nerve root distance （PIRD）, interpedicular distance （IPD）, pedicle width and height （PW, PH） were measured. Each parameter was analyzed with SPSS 11.5. Results： The mean RD, RA, RPD, PSRD, PIRD, IPD, PH and PW from L1 to L5 was 1.7±0.5mm-3.5±0.9mm, 41.8±9.2° -30.2v8.5° , 3.4±3.2mm- 15.3±5.9mm, 2.4＋1.1mm-1.8±0.5mm, 10.2±2.8mm-11.5±2.4mm, 21.4±1.8mm-24.4±2.Smm, 18.2± 1.7mm- 14.6±2.3mm and 8.0± 1.8mm-13.7±2.5mm, respectively. Statistical significant difference was noted at every segment with respect to RD, RA, RPD, PSRD, IPD, PH and PW （P〈0.05）. The mean RD, RPD, IPD and PW increased gradually from L1 to L5; on the contrary, the mean RA, PSRD and RH decreased gradually from L1 to L5. The mean IPD （L1 and L3） and PW （L1 and L4） were with significant difference between men and women （P〈0.05）. The mean IPD and PW of man were higher than those of women. Conclusion： The morphology of the lumbar nerve root and its surrounding structures can be detected by PROSET images non-invasively and accurately.