Dare A O, Balos L L, Grand W
Department of Neurosurgery, Louis Bakay Neuroscience Laboratories, School of Medicine and Biomedical Science, University at Buffalo, State University of New York 14209-1194, USA.
Neurosurgery. 2001 May;48(5):1142-5; discussion 1145-6. doi: 10.1097/00006123-200105000-00037.
To study the anatomic basis for olfaction-sparing anterior cranial base approaches.
The medial anterior skull base containing the olfactory unit and delimited by the inner table of the frontal sinus, the lesser wing of the sphenoid bone, and the medial orbital walls was removed from six cadaveric specimens. Histological methods were used to investigate the location, distribution, and depth of penetration of olfactory nerves. Hematoxylin and eosin and Gomori trichrome staining were used to visualize landmarks and architecture. S-100 neurofilament protein immunostaining was used to identify nerve fascicles and axons. In three cadaveric head specimens, olfaction-sparing craniofacial approaches were performed and the excised olfactory units were evaluated histologically.
Bundles of olfactory nerves were identified primarily in the nasal septum; relatively fewer bundles could be identified in the middle turbinate. Olfactory nerve endings were identified up to 20 mm below the cribriform plate (range, 7-20 mm). The superior and middle nasal meatus were most innervated; olfactory innervation was virtually absent in the inferior nasal meatus. Histological evaluation of the olfactory unit elevated during olfaction-sparing techniques routinely revealed transection of olfactory nerves that exited the skull base.
In olfaction-sparing anterior cranial base approaches, the olfactory nerves are inevitably transected. The clinical significance of olfactory nerve transection for postoperative functional recovery of olfaction remains to be analyzed.
研究保留嗅觉的前颅底入路的解剖学基础。
从6具尸体标本上移除包含嗅觉单元的前颅底内侧部分，其边界为额窦内板、蝶骨小翼和眶内侧壁。采用组织学方法研究嗅神经的位置、分布和穿透深度。苏木精-伊红染色和Gomori三色染色用于显示解剖标志和结构。S-100神经丝蛋白免疫染色用于识别神经束和轴突。在3具尸体头部标本上进行保留嗅觉的颅面入路手术，并对切除的嗅觉单元进行组织学评估。
嗅神经束主要见于鼻中隔，中鼻甲内的嗅神经束相对较少。在筛板下方20 mm处仍可识别出嗅神经末梢（范围为7 - 20 mm）。鼻上、中鼻道的神经支配最为丰富，鼻下鼻道几乎无嗅觉神经支配。对保留嗅觉技术中抬起的嗅觉单元进行组织学评估，通常显示穿出颅底的嗅神经被横断。
在保留嗅觉的前颅底入路中，嗅神经不可避免地会被横断。嗅神经横断对术后嗅觉功能恢复的临床意义仍有待分析。
