多层螺旋CT扫描图像数据对经蝶窦入路穿刺三叉神经节及其分支的可行性研究

Feasibility of transsphenoidal approach to trigeminal ganglion and its branches: image study of multi-slice spiral CT scanning

目的探讨经蝶窦入路穿刺三叉神经节及其分支的可行性,分析两者的毗邻关系及相关限制因素。方法对110例成年中国人头部薄层CT轴位原始资料进行多平面重组,观察圆孔、卵圆孔、翼腭窝(管)、Meckel腔与蝶窦外侧壁的关系,测量蝶窦外侧壁至诸结构的骨壁厚度。结果①圆孔紧靠蝶窦外侧壁的前外下方,骨壁厚度<2mm者84例(76%);②重组图像可显示翼腭管全程,翼腭窝与蝶窦前下外侧壁之间的骨壁厚度<2mm者77例(70%);③卵圆孔距离蝶窦外侧壁距离>5mm98例(89%);④由蝶窦腔内经颈内动脉管前方入路,斜向后下外方可及Meckel腔,骨壁厚度1～5mm,颈动脉管为重要骨性标志。结论经蝶窦内可分别穿刺或开放圆孔、翼腭窝和Meckel腔,而经蝶窦内穿刺卵圆孔基本不可行;经蝶窦入路至三叉神经节及其分支的可及性与蝶窦气腔的位置和扩展程度有关。

Objective To explore the feasibility of transsphenoidal approach to trigeminal ganglion and its branches, and to analyze key factors including their anatomic relationships and interrelated limiting factors for the approach. Methods Axial computed tomographic images of the cranial base from 110 Chinese adults were multiplanar-reformatted to present the foramen rotundum, foramen ovale, pterygopalatine fossa and Meckel cavity, and their position relationships with the lateral wall of the sphenoid sinus, and measure the thickness of these bony walls. Results ①The foramen rotundurn was adjacent to the lateral margin of the sphenoid sinus, located in the inferior-anterior part. The thickness of the bony wall was less than 2mm in 84 cases （76%）. ② The whole pterygopalatine canal could be displayed on the reformatting images. The thickness of the bony wall between the pterygopalatine fossa and the inferior-anterior lateral wall of the sphenoid sinus was less than 2 mm in 77 cases （70%）. ③The distance of the foramen ovale to the lateral wall of sphenoid sinus exceeded 5 mm in 98 cases （89%）. ④ The Meckel cavity could be accessed from the sphenoid sinus via anterior aspect of the internal carotid canal, and the thickness of the bony wall varied from I to 5 ram. The internal carotid canal could serve as the landmark. Conclusion The foramen rotundum, the pterygopalatine fossa and the Meckel cavity could be accessed, while the foramen ovale could not be assessed via the sphenoid sinus. The accessibility of transsphenoidal approach to trigeminal ganglion and its branches is related to the position and extension of the sphenoid air cell.