利用螺旋CT确定面神经管锥段位置

Application of Multislice Spiral CT in Locating the Pyramidal Segment of the Facial Canal

目的为临床医生提供面神经管锥段位置关系的信息。方法取15例开颅取脑后颅底标本,对面神经管锥段与外半规管凸、后骨半规管、锥隆起、鼓索隆起之间的直线距离进行直接测量与64层螺旋CT测量;对118例患者头颅CT扫描图像进行相同项目的测量。对颅底标本两种方法测量结果和男女患者头颅CT扫描资料测量结果分别进行t检验。结果尸骨直接测量与CT测量结果((x珚±s)mm,以下同)分别是1.49±0.61与1.55±0.60,2.27±1.02与2.19±1.07,3.31±1.31与3.39±1.28,3.78±1.26与3.87±1.42;两种方法测量值差异无显著统计学意义(P>0.05)。活体测量男女性的测量值分别为1.68±0.86与1.34±0.69,2.49±1.44与1.95±1.35,3.60±1.24与3.13±1.23,3.96±1.21与3.47±1.32;两性的测量值差异有显著统计学意义(P<0.05)。结论 CT测量方法可靠,测得值可信;CT扫描除可助医生明确诊断外,CT测量和面神经管的三维重建还可助临床医生术前、术中对面神经管锥段及其他解剖结构的定位与保护。在术中可以外半规管凸、后骨半规管、锥隆起对锥段定位;相反亦可以面神经定位骨半规管。

Objective To supply useful information on the location of the pyramidal segment of the facial canal for clinicians.Methods The distances from the pyramidal segment of the facial canal to the prominence of the lateral semicircular canal,the posterior semicircular canal,pyramidal eminence,and chordal eminence were measured directly and through 64-slice spiral CT on 15 cranial base specimens.The same parameters were also measured on CT images of skulls of 118 patients.To compare the measurements on specimens between the two methods and those on patients between males and females,t test was conducted.Results The distances,measured directly and through CT,from the pyramidal segment of the facial canal to the prominence of the lateral semicircular canal,the posterior semicircular canal,pyramidal eminence,and chordal eminence were 1.49±0.61 mm and 1.55±0.60 mm,2.27±1.02 mm and 2.19±1.07 mm,3.31±1.31 mm and 3.39±1.28 mm,3.78±1.26 mm and 3.87±1.42 mm,respectively;there was no statistically significant difference between the measurements by the two methods（P0.05）.The corresponding measurement values in male and female patients were 1.68±0.86 mm and 1.34±0.69 mm,2.49±1.44 mm and 1.95±1.35 mm,3.60±1.24 mm and 3.13±1.23 mm,3.96±1.21 mm and 3.47±1.32 mm,respectively;there was statistically significant difference between the measurements of male and female patients（P0.05）.Conclusion CT measurement,in combination with 3D reconstruction of the facial canal can be used to facilitate the localization of the pyramidal segment of the facial canal and related anatomical structures before and during operation.During operation,the lateral semicircular canal,posterior semicircular canal and pyramidal eminence are useful clues to the localization of pyramidal segment of the facial canal;facial nerves can also be used to localize semicircular canals.