Microanatomy of the Facial Nerve in Cerebellopontine Angle

Objective To study the microanatomy of the facial nerve in cerebellopontine angle (CPA).To study the microsurgical anatomy of the facial nerve in cerebellopontine angle (CPA).Methods The facial nerve were studied on 44 sides of 22 adult head specimens with surgical microscope.Results ① The origins of the motor root and the nervus intermedius were lateral to the abducent nervus. The distance between the motor root and the abducent nerve averaged 8.92mm,and the distance between nervus intermedius and the abducent nerve 10.97mm.② The facial nerve from the brain stem to the internal acoustic pore,the meeting point of the transverse and sigmoid sinuses and the trigeminal nerve origin averaged in length 14.40mm,40.02mm,5.60mm,respectively.③On the average the facial nerve at the site of internal acoustic pore was 31.56mm,11.03mm,7.18mm,7.66mm away from the meeting point of the transverse ,sigmoid sinuses trigeminal ganglion inferior arcuate fossa and the meeting point of the petrosal vein,respectively.④ The angle of the facial nerve to the sagittal plane,coronal plane and horizontal plane averaged 62.89°,18.51°and 35.55°,respectively.Conclusion There is close relationship between the facial nerve and the surroundings which are significant to the microsurgy in cerebellopontine angle.