中耳乳突手术相关面神经管解剖的多层螺旋CT测量

Measurement of anatomical relationships of facial nerve canal related to middle ear and mastoid surgery on multi-slice computed tomography-multiplanar reformation images

目的 利用多层螺旋CT多平面重组（MPR）技术研究中耳乳突手术相关面神经管解剖.方法 选取行颞骨高分辨率CT检查发现373侧耳没有颞骨骨质异常187例成人,将原始图像传至工作站行多平面重组（MPR）成像,在重组MPR图像上测量面神经管乳突段、后膝及鼓室段与周围重要结构的距离.结果 面神经管乳突段至颈静脉窝、乳突外侧缘、外耳道后壁、后颅窝硬膜板、乙状窦、鼓岬及蜗窗的距离分别为5.43、15.99、4.42、9.01、9.44、6.02和6.51 mm,面神经管后膝至锥隆起、后半规管的距离分别为2.64和3.12 mm,面神经管鼓室段至前庭窗、锤骨头、砧骨短突和外半规管的距离分别为1.19、2.27、3.09和0.90 mm.结论 利用多层螺旋CT MPR技术可以准确研究面神经管与周围解剖结构之间的关系,对中耳乳突手术中避免损伤面神经有重要的临床价值.

Objective To investigate the anatomical relationships of facial nerve canal related to middle ear and mastoid surgery by multi-slice computed tomography （MSCT） and its muhiplanar reconstruction （MPR） technology.Methods High-resolution CT scanning with multislice spiral CT of temporal bones without bone abnormality of 373 ears in 187 adult patients were examined.All original images were processed by MPR. The distances between facial nerve canal （FNC） and iugular foramen （JF）,lateral surface of mastoid bone （M）,external acoustic canal （EAC）,posterior fossa dural plate （PFD）,sigmoid sinus （SS）,promontory （P）,cochlear window （CW）,pyramidal eminence （PE）,posterior semicircular canal （PSC）,oval window （OW）,head of malleus （MH）,incus lenticular process （ILP） and lateral semicircular canal （LSC） were measured on different MPR images.These measurements were also analyzed with respects to side,gender,pneumatization and jugular foramen position differences.Results On average,FNC-JF was 5.43 mm,FNC-M 15.99 mm,FNC-EAC 4.42 mm,FNC-PFD 9.01 mm,FNC-SS 9.44 mm,FNC-P 6.02 mm,FNC-CW 6.51 mm,FNC-PE 2.64 mm,FNC-PSC 3.12 mm,FNC-OW 1.19 mm,FNC-MH 2.27 mm,FNC-ILP 3.09 mm and FNC-LSC 0.90 mm FNC-M was longer in males than that of females （P〈0.05）.FNC-JF and FNC-SS were longer on left side than those of the right （P〈0.05）.FNC-PFD was shorter on left side （P〈0.05）.FNC-PFD,FNC-EAC,FNC-SS and FNC-M were longer in well pneumatized mastoids than those of poorly pneumatized mastoids （P〈0.05）.FNC-PE was longer in poorlY pneumatized mastoids than that of well pneumatized mastoids （P〈0.05）.FNC-PFD,FNC-P,FNC-CW and FNC-PSC were longer in bones with jugular foramen vailation than those of bones without jugular foramen variation （P〈0.05）.FNC-JF,FNC-SS and FNC-M were longer in bones without iugular foramen variation than those of bones with iugular foramen variation （P〈0.05）.Conclusions Anatomical relationships of facial nerve canal related to middle gar and mastoid surgery can be accurately measured on MSCT-MPR images.It is helpful to avoid injuring facial nerve in middle ear and mastoid surgery.