视神经管的应用解剖学研究

Applied anatomy study of canalis opticus in treatment of optic canal decompression

目的通过视神经管(OC)的解剖学观察,为视神经管减压术切开部位提供参考。方法成年头颈部标本20例,观察OC的形态及测量相关数据,OC与筛窦和蝶窦的关系,眼动脉的走行等,寻找并确定手术标志。结果 OC的走行是从内上至前外下方向呈倒"八"字形,左、右侧OC与正中矢状面的夹角分别为(36.54°±1.98°)、(36.52°±1.73°)。OC与筛蝶窦的关系分为蝶旁型、筛旁型和筛蝶型。OC分内侧壁、外侧壁、上壁和下壁,有颅口、眶口。内侧壁最长、最薄;颅口呈横椭圆形,眶口呈竖椭圆形,OC中部横截面近圆形,是视神经管最狭窄的部位。沿OC的眶口向后,可见一条反光带即OC,32侧可见视神经管隆突,8侧未见明显的视神经管隆突。眼动脉在OC内与视神经的关系为:在颅口位于视神经内下方占80%,在管中部均位于视神经正下方,在眶口位于视神经外下方占85%。结论 OC内侧壁最薄,眼动脉穿行在OC内,位于视神经的内下方、正下方、外下方。视神经管减压术切开部位宜选择在内壁与上壁交界处,尤其在接近颅口处,以避免术中损伤眼动脉及颈内动脉。

Objective To explore the incision site of optic canal decompression by studying the anatomical structure of optic canal （ OC ）. Methods Totally 20 adult specimens of head and neck were prepared. Observed the form of optic canal and the relationship between the optic canal and the ethmoid sinus and sphenoidal sinus, and measured the data relating to the optic canal. At the same time, the courses of ophthalmic artery were observed and the surgery sign were determined. Results The course of OC is from the upper inside to the under outside of the front which looks like an inverted glyph of the Chinese character ＂八＂. The included angles between the median sagittal plane and the left OC and the right OC are respectively （36.54°± 1.98° ） and （36.52° ± 1.73° ）. The relation between OC and the sphenethmoid could be divided as beside the sphenoid sinus type, beside the ethmoid sinus type, and sphenethmoid type. The OC has the following four walls namely medial wall, lateral wall, superior wall, and inferior wall, and it has two apertures namely cranic aperture and orbital aperture. The medial wall of OC is measured to be the longest and the thinnest. The cranie aperture is ellipse, and the orbital aperture is vertical oval. The transverse in middle part of OC is approximately circular, and it is the most narrow part. A reflective strip namely OC can be seen back- wards along the OC orbital aperture. 32 side of eminentia eanalis optica are available while 8 side of it couldnt be seen obviously. There is 80% of ophthalmic artery goes inside below the eranic aperture and the ophthalmic artery goes under the optic nerve when it is in the middle of optic canal while the 85% of the ophthalmic artery goes outside below the optic canal when arriving the orbital aperture of optic canal. Conclusion The ophthalmic artery goes in the medial wall of optic canal which is the thinnest and the ophthalmic artery is under the optic nerve inside or outside it. So it would be safe to choose the junction of medial wall and superior wall when doing the endoscopic optic nerve decompression.