Geniculum of facial canal
Geniculum canalis facialis
- Latin synonym: Genu canalis nervi facialis; Geniculum canalis nervi facialis
- Synonym: Genu of facial canal
Definition
The geniculum of facial canal refers to a sharp bend in the facial canal where the first segment, the labyrinthine part, which runs laterally above the vestibule, turns backward. This point marks the transition from the labyrinthine part to the second segment, the tympanic part, of the facial canal.
The geniculum is important as it contains the geniculate ganglion. This ganglion is a group of nerve cells where the facial nerve's sensory and parasympathetic fibers are located. The parasympathetic fibers go to the lacrimal glands (i.e. the greater petrosal nerve) and help produce tears. The sensory fibers transmit taste sensations from the front two-thirds of the tongue.
References
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Text by Antoine Micheau, MD - Copyright IMAIOS and reviewed by Muhammad A. Javaid, MD, PhD © 2024 IMAIOS.
Drake, R.L., Vogl, A.W. and Mitchell, A.W.M. (2009). ‘Chapter 8: Head and Neck’ in Gray’s anatomy for Students. (2nd ed.) Philadelphia PA 19103-2899: Elsevier, pp. 917-919 & Fig. 8.124 (A, B).
Standring, S. and Gray, H. (2016). ‘Chapter 37: External and middle ear’ in Gray’s anatomy The anatomical Basis of Clinical Practice. (41st ed.) New York: Elsevier, pp. 639 & Fig. 37.14.
