CT结合MRI图像在定制腰椎新型完全后路人工椎体中的应用

Application of a new type of artificial lumbar vertebra with CT and MRI imaging via posterior-only approach

目的探讨CT结合MRI图像在定制腰椎新型完全后路人工椎体中应用的可行性。方法选取健康成年志愿者12名进行腰椎CT扫描,提取Dicom格式图像。采用Mimics 19.0图像软件获得L3椎体全部完整切除的脊柱图像,建立与L_2下终板与L_4上终板横断面匹配且层厚为6 mm的C型结构样人工椎体。获取MRI图像可以观察神经根走行,测量L_3椎体的横断面面积和椎体的高度。结果 L_2椎体下终板横截面和L_4椎体上终板横截面面积大小不一,但无论是男性还是女性,L_2椎体下终板与L_4椎体上终板的横截面面积、最大横径、最大矢状径比较差异无统计学意义(P>0.05)。矢状位MRI上,男性L_3椎体前缘高度为(48.28±4.58)mm,女性为(45.02±3.03)mm;男性L_3椎体后缘高度为(43.57±3.18)mm,女性为(38.52±0.97)mm。L_3人工椎体椎弓根钉位置的解剖重建有效避开了腰椎神经根。结论新型完全后路腰椎人工椎体可以有效重建椎体的完整性和稳定性,术前获取个性化CT及MRI图像定制新型人工椎体是避免围手术期神经损伤、有效恢复椎体高度的保障。

Objective To explore the feasibility of application of CT combined with MRI imaging in a new type artificial lumbar vertebra via posterior-only approach. Methods Twelve healthy adult volunteers were selected for lumbar spine CT scan, and Dicom format images were extracted. The Mimics 19.0 image software was used to obtain the spinal images of the complete resection of the L3 vertebral body, and to establish ac-type structure-like artificial vertebral body that matched the cross-sections of the lower endplate of L2 and the upper endplate of L4 with a thickness of 6 mm. MRI images could be obtained to observe the shape of nerve roots and measure the cross-sectional area and height of the L3 vertebral body. Results The cross-sectional area of the lower endplate of L2 vertebral body and the upper endplate of L, vertebral body were different, but there were no statistically significant differences in the cross-sectional area, maximum transverse diameter and maximum sagittal diameter between the lower endplate of Lz> vertebral body and the upper endplate of L4 vertebral body, no matter male or female (P >0.05). In lumbar sagittal MRI, the anterior margin height of L3 vertebral body was (48.28±4.58) mm in males and (45.02±3.03) mm in females. The posterior margin height of L3 vertebral body was (43.57±3.18) mm for male and (38.52±0.97) mm for female. The anatomic reconstruction of the position of L3 artificial vertebral body pedicle screw effectively avoided the lumbar nerve roots. Conclusion The new posterior-only lumbar artificial vertebra can effectively reconstruct the integrity and stability of the vertebral body. To obtain the personalized CT and MRI images preoperatively is the guarantee to avoid perioperative nerve injury and effectively restore vertebral height.