MRI测量对上胸椎肿瘤手术入路选择的意义

Pre-operative MRI measurement in choosing a proper surgical approach in dealing with upper thoracic tumors

目的:探讨术前MRI测量对上胸椎肿瘤前路切除手术入路选择的意义。方法:对8例上胸椎肿瘤患者术前进行MRI检查,在MRI矢状位图片上经胸骨切迹作与胸骨柄纵轴相垂直的线P,经病变椎体尾侧紧邻正常椎体的上、下终板作两个终板的切线E1和E2,分别记录P与脊柱相交的椎体水平及E1、E2与胸骨相交的椎体水平。P经过病变椎体远侧正常椎体,E1和E2经过胸骨切迹或其上方者采用低位颈前切口;E2经过胸骨柄上部者采用部分胸骨和/或部分内侧锁骨切除入路。P经过病变椎体或E1和E2经过胸骨柄中下部者采用后外侧经胸腔入路完成手术。结果:7例患者P经过病变椎体远侧正常椎体,其中4例E2经过胸骨切迹或其上方者有3例通过低位颈前切口完成了肿瘤的前路切除,1例显露不佳,切除少量左侧锁骨内侧部分增加显露后完成手术;3例E2经过胸骨柄上部者采用部分胸骨和/或部分内侧锁骨切除入路完成手术。1例P经过病变椎体,E1和E2经过胸骨柄中下部者采用后外侧经胸腔入路完成手术。未出现与手术相关的血管和神经损伤等并发症,3个月随访时内置物无松动、移位和断裂。结论:术前MRI测量有助于选择适当的手术入路,并可帮助判断肿瘤切除后胸椎前路的融合固定方式。

Objective：To investigate the meaning of pre-operative MRI measuring in choosing a proper surgical approach in dealing with upper thoracic tumors.Method：The preoperative MRI measurement from 8 patients with upper thoracic tumors were performed to plan the following surgical approach.A line which passes the suprasternal notch and perpendicular to the axis line of sternum was drawed and defined as line P,line E1 and E2 were 2 were defined as two lines tangently to the superior and inferior endplates of the adjacent health thoracic spine caudally respectively.The level where the P line across the vertebral column and the 2 intersection points in which E1 and E2 line pass the sternum were recorded.A hypothesis was made as following：when line P passed the caudal unaffected vertebrae,and line E1 and E2 passed the suprosternal notch or above it,then a low cervical anterior approach could be chosen;when line E2 passed the superior part of the sternum of manubrium,then a approach with partial sternotomy or clavicular removal could he chosen; when line P passed the affected vertebrae or line E2 passed the medium or inferior part of the sternum of manubrium,then a posterolateral thoracotomy approach could be choosed.Result：Line P passed the caudally unaffected vertebrae in 7 cases and the line E1 passed the suprosternal notch or above as well.Line E2 passed the suprosternal notch or above in 4 cases,among these,there were only 3 cases of tumor resection by the low cervical anterior approach.An complementary approach with left medial clavicular resection was made in 1 case for extensive exposure.Partial sternotomy or clavicular resection was done in 3 cases,in which the line E2 passed the superior part of the sternum manubrium.Posterolateral thoracotomy was done in 1 case,in which the line P passed the affected vertebrae,while line E1 and E2 passed the medium or inferior part of the sternum of manubrium as well.No neurologic complications or vertebral artery injury occurred with related to the operation.No implant loosening,migration or failure was found at 3 month＇s follow-up.Conclusion： Measuring under the sagittal MRI before surgery could be helpful in choosing the surgical approach and determining the methods of spinal reconstruction and fixation.