CT量化评分评估寰枢椎脱位及合并颅底凹陷症寰枢椎脱位复位难易程度的可行性研究

A feasibility study on CT quantitative scoring in assessing the reduction difficulty of atlantoaxial dislocation and basilar invagination

中文关键词:  寰枢椎脱位  颅底凹陷症  颈椎双向牵引  寰齿间隙  齿突距Chamberlain线垂直距离  复位

英文关键词:Atlantoaxial dislocation  Basilar invagination  Bidirectional traction of the cervical  Atlantodens interval  Vertical distance from dens to Chamberlain line  Reduction

中文摘要:

  【摘要】 目的：探讨应用CT量化评分评估寰枢椎脱位（atantoaxial dislocatiion，AAD）及合并颅底凹陷症（basilar invagination，BI）的AAD复位难易程度的可行性，为手术决策提供指导。方法：2018年3月~2019年12月，对88例AAD（BI/AAD）患者入院后行颈椎CT扫描，依据定义的影像特征进行量化评分：枢椎关节平整、水平，0分；枢椎关节轻度斜坡化，1分；枢椎关节严重斜坡化，1.5~2分；寰枢椎关节骨赘形成，2分；寰枢椎关节球窝畸形、寰枢椎关节交锁、寰枢椎关节骨痂、寰齿间隙骨性融合或阻挡，3分。分别计算双侧侧块关节及寰齿关节赋值的总和，然后根据总分将其分为4级：Ⅰ级，0~1分，Ⅱ级，2~3分，Ⅲ级，4~6分，Ⅳ级，7~9分。颈椎双向牵引1周后，在维持牵引状态下行CT检查，测量牵引前后的寰齿间隙距离（atlantodens interval，ADI）和齿突距Chamberlain线垂直距离（vertical distance from dens to Chamberlain line，VDDC），通过公式计算寰枢椎脱位的垂直复位率、水平复位率和总体复位率，比较各级总体复位率的差异，分析CT量化评分对判断AAD（BI/AAD）复位难易程度的价值。结果：88例患者中，Ⅰ级15例，Ⅱ级23例，Ⅲ级38例，Ⅳ级12例。Ⅰ、Ⅱ、Ⅲ级牵引前ADI值分别为7.3±3.4mm、8.1±3.7mm和8.8±4.1mm，经颈椎双向牵引1周后，ADI值分别为1.5±1.5mm，2.0±1.0mm和5.7±1.7mm，牵引前后有统计学差异（P<0.05）；Ⅳ级牵引前后ADI值分别为8.9±3.9mm和6.8±3.6mm，差异无统计学意义（P>0.05）。Ⅰ、Ⅱ、Ⅲ、Ⅳ级牵引前VDDC值分别为11.9±3.9mm、12.2±3.6mm、13.6±3.8mm和12.3±3.2mm，经颈椎双向牵引后VDDC分别为0.8±0.5mm、3.1±1.1mm、5.9±1.5mm和8.2±2.0mm，牵引前后有统计学差异（P<0.05）。各级经过颈椎双向牵引1周后总体复位率分别为（86.4±12.0）%、（67.6±8.0）%、（45.9±9.0）%和（28.4±13.0）%，各级间比较有统计学差异（P<0.05）。结论：应用CT影像量化评分有助于术前评估AAD（BI/AAD）患者的复位难易程度，从而为手术决策提供参考。

英文摘要:

  【Abstract】 Objectives: To explore the feasibility of applying CT quantitative scoring analysis in evaluating the reduction difficulty of atlantoaxial dislocation and basilar invagination, and to provide guidance for surgical decision-making. Methods: From March 2018 to December 2019, 88 patients with atlantoaxial dislocation underwent cervical thin-slice CT scans after admission. The quantitative scoring was based on the defined image features, inlcuding: 0 point, flat and horizontal atlantoaxial joint; 1 point, slightly sloped atlantoaxial joint; 1.5-2 points, more obvious sloped atlantoaxial joint; 2 points, osteophytes in atlantoaxial joint; 3 points, ball-and-socket deformity, interlocking, callus in atlantoaxial joint, and anlanto-odontoid bony fusion or blocking. The total scores of assignments of lateral mass joints and atlanto-odontoid joints on both sides were calculated separately, and divided into 4 grades: gradeⅠ(0-1 point); gradeⅡ(2-3 points); grade Ⅲ(4-6 points); and grade Ⅳ(7-9 points). After one week of bidirectional traction of the skull, CT scan was performed while maintaining the traction. The atlantodens interval(ADI) and vertical distance of dens to Chamberlain line(VDDC) before and after traction were measured, and the vertical reduction rate, horizontal reduction rate, and overall reduction rate of atlantoaxial dislocation were calculated. The difference in reduction rate of each group was compared, and the value of CT image scoring in judging the reduction difficulty of atlantoaxial dislocation was analyzed. Results: Of the 88 patients, 15 cases were of grade Ⅰ, 23 of grade Ⅱ, 38 of grade Ⅲ, and 12 of grade Ⅳ. The pre-traction ADI values of grades Ⅰ, Ⅱ and Ⅲ were 7.3±3.4mm, 8.1±3.7mm and 8.8±4.1mm, respectively, and after 1 week of bidirectional cervical traction, the ADI values were 1.5±1.5mm, 2.0±1.0mm and 5.7±1.7mm, respectively, and the statistical differences before and after traction were significant(P<0.05). The ADI values in group Ⅳ before and after traction were 8.9±3.9mm and 6.8±3.6mm respectively, there was no statistically significant difference(P>0.05). The pre-traction VDDC values of grades Ⅰ, Ⅱ, Ⅲ and Ⅳ were 11.9±3.9mm, 12.2±3.6mm, 13.6±3.8mm and 12.3±3.2mm, respectively, and the VDDC values after bidirectional cervical traction were 0.8±0.5mm, 3.1±1.1mm, 5.9±1.5mm and 8.2±2.0mm, respectively, and the statistical differences before and after traction were significant(P<0.05). The overall reduction rates were (86.4±12.0)%, (67.6±8.0)%, (45.9±9.0)%, and (28.4±13.0)% after one week of bi-directional traction of the skull, and the statistical differences between groups were significant(P<0.05). Conclusions: The quantitative scoring method using CT images can help judge the difficulty of atlantoaxial reduction and provide a reference for surgical decision-making.