术中CT导航在先天性颅颈畸形后路固定中的应用

Intraoperative computed tomography with integrated navigation system for complex craniovertebral junction stabilization

目的探讨术中CT与导航系统在先天性颅颈交界区畸形后路固定手术中的应用价值。方法本组23例患者畸形复杂，男11例，女12例，年龄19—52岁，平均33．5岁。其中3例外院行单纯后颅窝减压术，采用术中CT导航下后路修补枕颈固定术，12例经口齿状突磨除术后，行二期术中CT导航下后路固定术，单纯行术中CT导航下后路减压固定术8例。结果导航下后路寰椎侧块、枢椎椎弓根螺钉固定7例，经寰枢关节螺钉固定6例，枕颈钉棒系统固定10例，导航验证准确度平均为1．8mm（0．6—2．2mm）。术中发现2例椎弓根螺钉位置不佳，术中调整后CT验证螺钉位置满意。根据术前及术后6个月Nurick分级，21例（91％）患者症状改善1级以上，2例（9％）患者症状无明显改善。本组病例无术中椎动脉及神经功能损伤等并发症。结论术中CT结合导航系统可以术中及时评价寰枢关节复位情况和植入螺钉的位置及深度，有效地避免了患者二次手术的风险；对于提高手术定位精度、优化手术路径及提高手术成功率等具有重要意义。

Objective To evaluate workflow, feasibility, and clinical outcome of fixation procedures with intraoperative computed tomography image - guided navigation for complex eraniovertebral junction malformation （CVJM）. Methods We present 23 cases that outline our experience with intraoperative CT scanning for navigated fixation procedures, among whom, 11 were male, and 12 were female. The ages of these patients were 19- 52 years （mean： 33.5 years）. All patients were treated with combination of bone grafting with rod and screw fixation systems. 7 patients underwent C1 lateral mass and C2 pedicle screw fixation. C1-2 transartieular screw fixation were performed in 6 patients. Moreover, because of the complex changes in geometry and bony structure, 10 patients were treated with individualized fixation surgery. Results There were no vascular or neural complications but pedicle perforation were detected in 2 patients which were corrected intraoperatively. All patients were clinically evaluated by Nurick grade criteria and concerning neurologie deficits 6 - month after surgery. 21 patients （91%） improved at least 1 Nurick grade, whereas the grade did not change in 2 （9%） patients. Craniovertebral stability and solid bone fusion were achieved in all patients. NNS was found to correlate well with the intra - operative findings and the recalibration was uneventful in all cases with an accuracy of 1.8 mm （0.6 - 2.2mm）. Conclusions iCT scanning with integrated NNS was found both feasible and beneficial in the surgical management of complex CVJM. In this unusual patient population, the technique appeared to be of value in negotiating complex anatomy and achieving a more controllable screw placement.