嗅神经的形态学特点及术中保护

Microsurgical anatomic features and intraoperative preservation of the olfactory nerve

目的进一步明确嗅神经的显微解剖学特点,为手术入路中嗅神经保护提供形态学基础。方法 (1)15例(30侧)颅骨干标本,进行筛板区的观察和测量;(2)15例(30侧)头颅湿标本,显微镜下解剖嗅球、嗅束及嗅三角区,对嗅神经的显微解剖学特点进行观察、拍照。结果筛孔分布在颅前窝中线两侧长(19.77±1.23)mm、中点处宽(3.15±0.45)mm的蝶形陷凹内;鼻甲侧筛孔数目明显多于鼻中隔侧,鸡冠两侧筛孔相对密集。嗅神经由嗅鞘包裹,于嗅窝内终止于嗅球,嗅球后极延续为嗅束,走行在额叶底面直回与内侧眶回之间。嗅束于前穿质前部分为内侧嗅纹、外侧嗅纹进入脑实质。结论熟悉嗅神经的显微解剖特点,有利于提高手术中嗅神经的保护,从而提高手术质量,减少并发症的发生率。

Objective To review microsurgical anatomic features of the olfactory nerve and suggest operative nuances that may contribute to reducing the rate of postoperative olfactory dysfunction. Methods Region of ethmoidal plate of 15 dry skulls （30 sides） were observed and measurements among the ethmoidal plate and those related structures were carried out. Microsurgical dissection was carried out in 15 cadaveric heads filled with colored latex to obtain the anatomic features of the olfactory bulb, olfactory tract and olfactory trigone. Results Cribroethmoid foramen with butterfly-like shape were distributed in an area with a length （19.77±1.23） mm, and the transverse diameter in the midpoint was （3.15±0.45） mm. The number of cribroethmoid foramen in nasal concha were denser than in septum（t=8.179,P〈0.01）.The olfactory tract enveloped by olfactory cistern was situated in the shallow part of the olfactory sulcus, being interposed between the gyrus rectus and the medial orbital gyri. The olfactory trigone is divided into medial and lateral olfactory strains in front of the anterior perforated substance. The arterial supply in most cases of the olfactory nerve was relatively independent. And the blood supply was segmental in a few cases. Conclusions The olfactory never is located in the anterior skull base in the shape of triangle cone. The arterial supply in most cases of the olfactory nerve was relatively independent. Knowledge of the microsurgical features would help to preserve the olfactary nerve and avoid postoperative complications.