旁中线颅底鼻内镜手术入路及其应用解剖学研究

Lateral midline skull base transnasal endoscopic approach and its applied anatomy study

目的鼻内镜下经鼻联合上颌窦入路探索鼻咽咽鼓管区、翼腭窝、颞下窝旁中线颅底重要解剖结构,为手术处理该区域病变提供解剖学依据,并用颅底恒定的解剖标志定位咽旁间隙段颈内动脉。方法用Mimics软件对100具成人鼻颅底CT进行三维重建,在重建模型上进行与颅底相关的结构测量;并对10具湿性头颅标本行鼻内镜下旁中线颅底解剖,联合鼻腔-上颌窦入路,依次解剖鼻咽咽鼓管区、翼腭窝及颞下窝的重要神经血管、肌肉及骨性解剖标志。结果翼管后端、破裂孔内缘、颈动脉管外口内缘、颈静脉孔内缘到中线距离分别为:(13.16±1.33)mm、(11.54±0.89)mm、(28.97±1.69)mm、(28.63±1.40)mm;犁骨后缘中点到双侧颈动脉管外口前缘连线的距离为(16.52±2.21)mm,到单侧颈动脉管外口的距离为(31.81±1.80)mm,角度为(57.6±2.76)°。蝶骨角棘包绕咽鼓管骨口,其与颈动脉管外口前后相距(5.92±1.02)mm。结论鼻内镜下经鼻联合上颌窦入路进行鼻咽咽鼓管区、翼腭窝、颞下窝旁中线颅底解剖有足够的手术空间;犁骨后根、破裂孔、圆孔、卵圆孔、蝶骨角棘、颈动脉管外口为旁中线颅底重要的骨性标志。以中线为基线,术中沿中线由犁骨后根向深部分离约1.7cm即可到达双侧颈动脉管外口连线平面,此外犁骨后根沿旁开约58°、向深部分离约3.2cm也可到达单侧颈动脉管外口前缘,蝶骨角棘也可作为颈动脉管外口前界标志,两者前后相距约6mm,术中注意此安全界限并谨慎操作,可以避免损伤咽旁间隙上段颈内动脉。

Objective To investigate anatomic landmarks of nasopharynx,eustachian tube,pterygopalatine fossa（PPF） and infratemporal fossa（ITF）,and to orientate the internal carotid artery（ICA） in parapharyngeal space under endoscopic combined transmaxillary-transnasal approach,in an attempt to perform operations of the paramidline skull base successfully and safely.Methods 100 normal adult heads（200 sides） were CT-scanned and reconstructed three-dimensionally under Mimics,and anatomical data was measured and recorded.Important endoscopic landmarks of nasopharynx,eustachian tube,PPF and ITF were dissected in 10 fixed cadaver heads via combined approach.Results The distances between the median line and posterior border of vidian canal,interior border of foramen lacerum,outer foreman of the carotid canal,and jugular foramen were（13.16±1.33）mm,（11.54±0.89）mm,（28.97±1.69）mm,and（28.63±1.40）mm respectively.The distance from middle point of the posterior border of vomer to bilateral anterior border of outer foreman of carotid canal was（16.52±2.21）mm,and the distances and angle from middle point of the posterior border of vomer to unilateral anterior border of outer foreman of carotid canal were（31.81±1.80）mm,（57.6±2.76）° respectively.The alar spine of sphenoid bone enclosed bony portion of eustachian tube from outside,and the distance between alar spine and outer foreman of carotid canal was（5.92±1.02）mm.Conclusion Outer foreman of carotid canal can be reached by two ways：dissecting forward by 1.7 cm along the midline from posterior border of vomer,or dissecting forward by 3.2cm with an angle of 60° aside from posterior border of vomer.The important anatomic structures of nasopharynx,eustachian tube,PPF and ITF can be visualized clearly and comprehensively through combined transmaxillary-transnasal approach.The posterior margin of vomer,foramen lacerum,foramen rotundum,fossa ovale,alar spine of sphenoid bone,and outer foreman of carotid canal are important landmarks in paramidline skull base dissection.The alar spine of sphenoid bone can also be treated as a landmark of anterior border of outer foreman of carotid canal,and the distance between them are about 6mm.The internal carotid artery in parapharyngeal space will be less likely injured if the boundary is kept and surgery is operated carefully.