椎板下棘64层CT三维重组和MRI的影像学研究

Imaging characteristics of inferior spine of vertebral lamina using 64-slice spiral CT3D reformation and 1.5T MRI

目的:观察椎板下棘在MSCT三维重组图像及MRI图像上的形态特点和影像学表现,为椎板下棘的影像学诊断和手术治疗提供解剖学依据。方法:对脊椎64层MSCT扫描发现有椎板下棘的211例患者进行CT三维图像重组,并测量其长度,其中57例行MRI扫描,观察椎板下棘的部位、形态及其与硬膜囊和椎间管的关系等。结果:椎板下棘出现于Th2～L5,出现率较高的椎体有Th11、Th12及L1、L5,达78.7%。侧别、性别及相邻节段间差异均有显著性意义(P<0.01),长度均值较大的节段男性为Th11、Th12,女性为Th11、Th12、L1和L5,最大均值均位于Th12,分别为(4.64±1.18)mm和(4.94±1.96)mm。胸段及部分上腰段的椎板下棘95%为长条状,相对窄基底,位于黄韧带的外侧缘,尖端指向下方,有275个(89%)椎板下棘压迫硬膜囊,有15个(5%)椎板下棘压迫椎间管。下腰段的椎板下棘87%为较宽基底的锥状,尖端指向前外下方,常常超过黄韧带的范围,有122个(91%)椎板下棘压迫椎间管,有12个(9%)椎板下棘压迫硬膜囊。结论:脊椎64层MSCT矢状面、冠状面三维重组能清楚显示椎板下棘的位置、大小、形态及其与椎管、椎间管的毗邻关系;脊椎MRI扫描则能显示椎板下棘对硬膜囊的压迫情况,将两者结合起来,对椎板下棘的正确诊断有重要价值。

Objective：To study the imaging characteristics of inferior spine of vertebral lamina （ISVL） using 64-slice spiral CT 3D reformation and MRI, in order to provide the anatomical basis for the diagnosis and surgical treatment. Methods：211 patients with ISVL revealed by 64-slice spiral CT were post-processed with 3D reconstruction, the length of ISLVs was measured. Of the 211 patients, MRI were performed in 57 patients, the position, shape of ISVL and their relationship with dural sac and intervertebral canal were studied. Results： ISVL were found at the level of vertebra Th2-L5, mostly at the level of Th11,Th12 and L1 ,L5 ,the rate of occurrence at this level could be reached up to 78. 7%. Significant statistical differences could be seen in different sides, sex and adjacent segments （P〈0.01）. The largest mean value of length located at the region of Th11 , Th12 in male,Th11 ,Th12, L1 and L5 in female, while the longest mean value of length was Thee ,which was （4.64±1. 18）mm and （4. 94±1.96）mm respectively. 95% of the ISVL thoracic and upper lumbar vertebra were linear or stripe in shape, with relative narrow base, locating at the lateral surface of ligamenta flava and pointed downwards. Dural sac were compressed in 275 （89%） of ISLVs and intervertebral canal were compressed in 15 （5M）. 87G of the ISVL at the level of lower lumbar vertebra showed relatively wide base and pointed anteriorly,laterally and inferiorly, frequently exceeded the range of ligamenta flava. Intervertebral canal was compressed by 122 （91%） of ISVL,the dural sac was compressed by 12 （9%）. Conclusion： The location, size, pattern of ISVL and their relation with spinal canal/intervertebral canal could be displayed by saggital and coronal reconstruction of 64-slice spiral CT scanning, while the compression of dural sac could be displayed on MRI. Combination of CT 3D reformation and MRI can provide accurate diagnosis.