背景:术中神经监测(IONM)警报是后凸畸形矫正手术的令人担忧的事件之一,会导致术后神经功能缺损.据我们所知,在接受脊柱后凸手术的患者中,没有风险预测评分来预测此类事件。
目的:开发一种新的术前基于MRI的脐带形态分类(CMC)和风险预测评分,用于预测后凸畸形患者的IONM警报。
方法:前瞻性收集数据的回顾性分析患者样本:114例接受后凸畸形手术矫正的患者预后指标:使用AIS分级进行术中神经监测警报和术后神经状况。
方法:对脊柱后凸畸形后路脊柱融合术患者进行回顾性分析。根据MRI的脊髓和周围脑脊液的形态,有五种类型的绳索。1型(正常索):圆形索,在索和先端之间周围可见CSF,2型(扁平的绳索):在顶点处扭曲<50%的绳索,前CSF消失;3型(变形的绳索):在顶点处扭曲>50%的绳索,周围的CSF完全消失;4型(拉伸的绳索):绳索在曲线的顶点上被拉伸并萎缩。类型5(平移绳):根尖处的绳水平平移,脊柱屈曲塌陷。术前X线片用于测量术前矢状cobbs角,矢状畸形角比(S-DAR),矢状垂直轴(SVA),曲线的顶点,和脊柱后凸的类型。临床数据,如症状持续时间,脊髓病的临床症状,神经状态(AIS等级),使用mJOA评分的脊髓病分级,并记录截骨类型.使用多变量逻辑回归来确定IONM警报的危险因素,并开发了风险预测评分,该评分已在30名患者的新队列中得到验证。
结果:共有114名患者符合纳入标准。记录了33例患者(28.9%)的IONM警报,25例患者信号完全恢复,8例患者术后缺损。在类型5中,IONM警报的发生率明显更高(66%),其次是类型4(50%),类型3(21.1%),类型2(11.1%),和1型(11.1%)(p值<0.001)。基于多元逻辑回归,七个因素,即术前神经状况,mJOA评分≤6,存在脊髓病的迹象,T5以上的曲线顶点,术前矢状cobbs,S-DAR,和基于MRI的CMC,被确定为风险预测因子。危险因素的值从0到4不等,最大总风险评分为13。6的截断值具有良好的敏感性(84.9%)和特异性(77.8%),表明IONM警报的高风险。预测模型的AUC为0.92,表明良好的判别能力。
结论:我们开发并验证了风险预测评分,该评分可识别在脊柱后凸手术期间存在IONM警报风险的患者。识别此类高危患者(风险评分≥6)有助于正确评估和术前咨询,并有助于为治疗策略提供适当的循证参考。
BACKGROUND: Intraoperative
neuromonitoring (IONM) alert is one of the worrying events of kyphosis corrective surgery, which can result in a postoperative neurological deficit. To our knowledge, there is no risk prediction score to predict such events in patients undergoing kyphosis surgery.
OBJECTIVE: To develop a new preoperative MRI-based cord morphology classification (CMC) and risk prediction score for predicting IONM alerts in patients with kyphotic deformity.
METHODS: Retrospective analysis of prospectively collected data.
METHODS: About 114 patients undergoing surgical correction for kyphotic deformity.
METHODS: Intraoperative
neuromonitoring alerts and postoperative neurological status using AIS grading.
METHODS: Kyphotic deformity patients undergoing posterior spinal fusion were retrospectively reviewed. Based on the morphology of the spinal cord and surrounding CSF in MRI, there are 5 types of cord. Type 1 (normal cord): circular cord with surrounding visible CSF between the cord and the apex, Type 2 (flattened cord): cord with <50% distortion at the apex with obliteration of the anterior CSF; Type 3 (deformed cord): cord with >50% distortion at the apex with complete obliteration of the surrounding CSF; Type 4 (stretched cord): the cord is stretched and atrophied over the apex of the curve. Type 5 (translated cord): horizontal translation of the cord at the apex with buckling collapse of the vertebral column. Preoperative radiographs were used to measure the preoperative sagittal cobbs angle, sagittal deformity angular ratio (S-DAR), sagittal vertical axis (SVA), apex of the curve, and type of kyphosis. Clinical data like the duration of symptoms, clinical signs of myelopathy, neurological status (AIS grade), grade of myelopathy using the mJOA score, and type of osteotomy were documented. Multivariate logistic regression was used to determine the risk factors for IONM alerts and the risk prediction score was developed which was validated with new cohort of 30 patients.
RESULTS: A total of 114 patients met the inclusion criteria. IONM alerts were documented in 33 patients (28.9%), with full recovery of the signal in 25 patients and a postoperative deficit in 8 patients. Rate of IONM alerts was significantly higher in Type 5 (66%), followed by Type 4 (50%), Type 3 (21.1%), Type 2 (11.1%), and Type 1 (11.1%) (p-value<.001). Based on multiple logistic regression, 7 factors, namely preoperative neurological status, mJOA score≤6, presence of signs of myelopathy, apex of the curve above T5, preoperative sagittal cobbs, S-DAR, and MRI-based CMC, were identified as risk predictors. The value for the risk factors varies from 0 to 4, and the maximum total risk score was 13. The cut-off value of 6 had good sensitivity (84.9%) and specificity (77.8%) indicating a high risk for IONM alerts. The AUC of the predictive model was 0.92, indicating excellent discriminative ability.
CONCLUSIONS: We developed and validated a risk predictive score that identifies patients at risk of IONM alerts during kyphosis surgery. Identification of such high-risk patients (risk score≥6) helps in proper evaluation and preoperative counselling and helps in providing a proper evidence-based reference for treatment strategies.