The ganglion is located in a bony structure that’s called the facial canal.
Its involved in taste, the secretion of tears and saliva, facial expression, and several other functions.
Anatomy
A nerve ganglion is a group of nerves enclosed by a capsule of connective tissue.
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Typically, all of the nerves in a ganglion will have similar or related functions.
The plural of ganglion is ganglia.
You have 12 cranial nerve ganglia on each side of your brain.
As with nerves, theyre generally referred to in the singular even though they exist in generally symmetrical pairs.
Those are called mixed nerves.
Four of your cranial nerve ganglia are parasympathetic and eight are sensory.
You may have heard of ganglion cysts, which shouldnt be confused with neural ganglia.
One root is motor and the other is sensory.
Inside your skull, the two roots travel forward and pass near the inner ear.
There, they enter a Z-shaped structure called the facial canal.
In the facial canal, the two roots fuse together.
At the first bend of the Z, they form the geniculate ganglion.
The word “geniculate” is from the Latin word for knee, which is genu.
In modern usage, it means “having knee-like bends or joints.”
Associated Conditions
The geniculate ganglion can be damaged by trauma or disease.
Several medical conditions are associated with it, determined by the exact location and the nature of the damage.
When shingles strikes near the geniculate ganglion, it causes Ramsay Hunt syndrome.
This typically happens only on one side of the face at a time.
Vaccinesfor chickenpoxandshinglesare the best defense against Ramsay Hunt syndrome.
Bells palsy is due to inflammation of unknown origin involving the geniculate ganglion.
That can compress the facial nerve inside the fallopian canal.
Symptomsof Bells palsy can vary.
Geniculate Ganglion Schwannoma
This ganglion may develop a rare tumor called a geniculate ganglion schwannoma.
Symptomsinclude:
Some cases of geniculate ganglion schwannoma dont requiretreatment.
In those that do, microsurgery may be done to repair the facial nerve.
National Institutes of Health: National Institute of Neurological Disorders and Stroke.Bells palsy fact sheet.
American Journal of Neuroradiology.Geniculate ganglion schwannoma.
