The facial nerve (7th. cranial nerve) runs in the bony canal. Its course is the most complicated among cranial nerves, and can be divided into mental, horizontal, vertical, and peripheral parts. The variations and anomalies of the facial nerve are closely related to the development of neighboring structures such as the inner and middle ear. In spite of nn increasing needs for knowledge of development and anatomy of the facial nerve, reports on the development of the facial nerve and its branches are few.
The author made serial sections of 22 human embryos ranging from Cnrnegie stage 12 to stage 22, reconstructed the findings of serial sections into three dimensional model with the aid of computer graphics, and pursed facial nerve to research its development during the embryonic period.
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