Kakizawa Yukinari, Abe Hiroshi, Fukushima Yutaka, Hongo Kazuhiro, El-Khouly Hatem, Rhoton Albert L
Department of Neurological Surgery, University of Florida, Gainesville, Florida, USA.
Neurosurgery. 2007 Sep;61(3 Suppl):15-23; discussion 23. doi: 10.1227/01.neu.0000289707.49684.a3.
The course of the lesser petrosal nerve is not well understood and may be confused with the course of the greater petrosal nerve during middle fossa surgery. The objective was to examine the course of the lesser petrosal nerve along the floor of the middle cranial fossa from the region of the geniculate ganglion to its outlet from the skull base. There are no studies focused on the course of this nerve in relationship to the floor of the middle cranial fossa.
Twenty middle fossae from adult cadaveric specimens were examined using 3 to 40x magnification.
The lesser petrosal nerve was partially exposed on the floor of the middle fossa without drilling in 75% of the middle fossae and totally covered by thin bone in 25%. It crossed the floor anterior to the greater petrosal nerve and exited the middle fossa through the canaliculus innominatus in 14 cases, foramen spinosum in 3 cases, and the sphenopetrosal suture in 3 cases. The course of the lesser petrosal nerve has been shown in textbooks to be parallel to the greater petrosal nerve. However, the lesser and greater petrosal nerves diverged in the area medial to the geniculate ganglion in 90% of middle fossae with the angle of divergence averaging 11.6 degrees. The course of the lesser petrosal nerve was divided into three patterns based on the site of confluence of the three bundles of fibers forming the nerve.
The relationships of the lesser petrosal nerve in the middle cranial fossa have been described. An understanding of these relationships will reduce the likelihood of it being confused with the greater petrosal nerve during surgical approaches to the middle fossa.
岩小神经的走行尚未完全明确，在中颅窝手术中可能与岩大神经的走行相混淆。本研究旨在观察岩小神经从中颅窝底的膝状神经节区域至其穿出颅底处的走行。目前尚无关于该神经与中颅窝底关系的研究。
使用3至40倍放大倍数对20个成人尸体标本的中颅窝进行检查。
75%的中颅窝中，岩小神经在未钻孔的情况下部分暴露于中颅窝底，25%被薄骨完全覆盖。它在岩大神经前方穿过中颅窝底，14例通过无名小管穿出中颅窝，3例通过棘孔穿出，3例通过蝶岩缝穿出。教科书显示岩小神经的走行与岩大神经平行。然而，在90%的中颅窝中，岩小神经和岩大神经在膝状神经节内侧区域分开，分开角度平均为11.6度。根据构成该神经的三束纤维的汇合部位，将岩小神经的走行分为三种模式。
描述了岩小神经在中颅窝中的关系。了解这些关系将降低在中颅窝手术中其与岩大神经混淆的可能性。
