门齿中点与外耳道中点假想连线对经鼻蝶入路的定位作用

Location effect of imaginary line between the midpoint of incisors and midpoint of the external auditory canal in the transsphenoidal approach

目的探讨经鼻蝶入路手术的一种方便、实用的解剖定位方法。方法在14例(28侧)尸头标本上模拟经鼻蝶入路,尸头取正中后仰位,侧面观察使门齿中点与外耳道中点假想连线垂直于地面,鼻窥器平行于这一连线逐步深入进入鼻腔进行观察。在矢状位上验证这一假想连线对定位的准确性,同时测量相关解剖结构的数据。结果按照前述方法模拟手术,鼻窥器所撑开范围的头侧部分可见蝶窦的骨性开口,尾侧部分是蝶窦前壁;开放蝶窦后同样发现鼻窥器所撑开范围的头侧正是鞍底。尸头正中矢状位解剖证实手术的准确性。鼻前棘至蝶窦开口的距离为(56.65±4.20)mm,鼻前棘至鞍底的距离为(71.30±4.56)mm。结论头颅侧面观门齿中点与外耳道中点的假想连线对经鼻蝶入路手术的方向性有重要的参考作用。

Objective To explore a convenient and practical method for anatomical location in the transsphenoidal surgery. Methods The transsphenoidal surgery was performed on 14 head cadavers （28 sides）, which were put in median overhead position. The imaginary line between the midpoint of incisors and the midpoint of the external auditory canal was perpendicular to floor when viewed from side. Being parallel to the line, nasal speculum was penetrated into the nasal cavity gradually in order to observe the anatomical structures. The accuracy of the imaginary line was verified in a sagittal view and the data of corresponding anatomical structures were measured. Results The surgery was simulated according to above method, the bony opening of the sphenoid sinus was found in the head part distracted by nasal speculum and the anterior wall of the sphenoid sinus in the caudal part. After opening the sphenoid sinus, the sellar floor was just in the head part distracted by nasal speculum. The accuracy of surgery was verified by median sagittal anatomy of cadaver head. The distance between anterior nasal spine and opening of sphenoid sinus was （56.65 ± 4.20） mm. The distance between anterior nasal spine and sellar floor was （71.30 ± 4.56） mm. Conclusion The imaginary line between the midpoint of incisors and the midpoint of the external auditory canal in head when viewed from side can offer important reference for the direction oftranssphenoidal surgery.