腰神经根、丛及分支CT重建整体形态及其临床意义的探讨

目的 探讨利用CT对腰神经(LN)进行多平面重建同层显示下的整体解剖学特征及其临床价值.方法 选取无腰腿痛病史、骨科专科检查无异常体征、经CT检查并按CT诊断标准确诊为腰椎正常的成年志愿者50名及30例(51条)LN病变者(腰椎间盘突出10例10条,椎管狭窄8例11条,椎体滑脱5例10条,脊髓栓系1例8条、腰椎侧弯曲畸形1例6条及创伤5例6条).使用美国GE公司制造的Light Speed 16层螺旋CT对其腰椎进行扫描,在工作站ADW4.1利用UNIX系统DICOM格式行LN多平面重建,使其同层显示,观察其整体解剖学特征及病变者的主要异常表现.结果 LN根、丛及分支CT重建结果显示:正常LN呈索条状走行,略低于肌肉的密度;每条LN与硬膜囊呈锐角走出;清晰显示腰丛及其主要分支闭孔神经、股神经、生殖神经等走行及其毗邻关系;显示的节段数百分比大小与重建角度密切相关:斜冠状面>斜冠状外旋切面>斜矢状外旋切面>冠状面>矢状切面.异常LN的主要表现有:受压移位50条(98.0%)、形态学变化49条(96.1%)、粘连41条(80.4%)、萎缩43条(83.3%),增粗8条(15.7%).结论 CT的多平面重建同层显示技术可整体显示LN形态及其走行的方向、毗邻关系等解剖学特征以及有无卡压等基本病变表现,在腰椎疾病诊断中有重要的应用价值.

Study on the overall anatomical features and clinical value of lumbar nerve root, plexus and branches in CT reconstruction

Objective To identify the overall anatomical characteristics and the clinical value of the lumbar nerves under CT multiplanar reconstruction. Methods Fifty normal subjects and 30 patients with LN diseases (51 sides) were selected, including 10 patients with lumber intervertebral disk hernia, eight patients with spinal stenosis, 5 patients with spondylolisthesis, 1 patient with tethered cord syndrome, lpatient with lumbar scoliosis, and 5 patients with spinal trauma. The 16-slice helical CT ( Light Speed, GE Company) was used for scanning the lumbar vertebra with multiplanar reconstruction in Workstation (ADW4.1) with UNIX System in DICOM format. The image was set on the same slice for the overall anatomy and manifestations of the lesions. Results The same-slice imaging showed the strip-like LN slightly lower than the surrounding muscle in density. Each LN went out of the dural sac at an acute angle. The course of the lumbar plexus and its major branches, including the obturator nerve, femoral nerve and reproductive nerve, and their relations to the adjacent structures were clearly revealed. The percentage of the segments displayed was well associated with the reconstruction angle, with the order being oblique coronal> outward-rotated oblique coronal > oblique sagittal > coronal > sagittal section. The major manifestations of abnormal LN included compression and displacement (50 sides, 98.0% ), morphological changes (49 sides, 96.1% ), adhesion (41 sides, 80.4% ). Conclusions The CT multiplanar reconstruction is ideal for the imaging of the overall size, shape, running and tension of the LN root; it is valuable in clinical diagnosis.