Otic ganglion
Encyclopedia
The otic ganglion is a small, oval shaped, flattened parasympathetic ganglion of a reddish-gray color, located immediately below the foramen ovale
in the infratemporal fossa
. It gives innervation to the parotid gland
for salivation.
It is one of four parasympathetic ganglia of the head and neck. (The others are the submandibular ganglion
, pterygopalatine ganglion
, and ciliary ganglion
).
It is occasionally absent.
.
Preganglionic parasympathetic fibres reach it from the glossopharyngeal nerve (and possibly also from the facial nerve) via the lesser petrosal nerve
continued from the tympanic plexus
. Postganglionic parasympathetic fibres from the ganglion pass with the sympathetic fibres mainly in the auriculotemporal nerve (a branch of CN V3 -- the Mandibular branch of the Trigeminal Nerve
) to supply the parotid gland. All postsynaptic parasympathetics will use some branch of the Trigeminal Nerve to get from one of four parasympatheic ganglia (Otic, Ciliary, Submandibular, and Peteryopalatine) to their destination in either smooth muscle or glandular tissue (secretomotor).
A slender filament (sphenoidal) ascends from it to the nerve of the Pterygoid canal
, and a small branch connects it with the chorda tympani
.
It is connected by two or three short filaments with the nerve to the Pterygoideus internus, from which it may obtain a motor, and possibly a sensory root.
, and one to the Tensor veli palatini.
The former passes backward, lateral to the auditory tube; the latter arises from the ganglion, near the origin of the nerve to the Pterygoideus internus, and is directed forward.
The fibers of these nerves are, however, mainly derived from the nerve to the Pterygoideus internus.
Foramen ovale (skull)
At the base of the skull the foramen ovale is one of the larger of the several holes that transmit nerves through the skull. The foramen ovale is situated in the posterior part of the sphenoid bone, posterolateral to the foramen rotundum.-Contents:Several nerves, arteries and veins pass through...
in the infratemporal fossa
Infratemporal fossa
The infratemporal fossa is an irregularly shaped cavity, situated below and medial to the zygomatic arch.* anteriorly, by the infratemporal surface of the maxilla and the ridge which descends from its zygomatic process...
. It gives innervation to the parotid gland
Parotid gland
The paired parotid glands are the largest of the salivary glands. They are each found wrapped around the mandibular ramus, and secrete saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches.-Location:The parotid glands...
for salivation.
It is one of four parasympathetic ganglia of the head and neck. (The others are the submandibular ganglion
Submandibular ganglion
The submandibular ganglion is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck...
, pterygopalatine ganglion
Pterygopalatine ganglion
The pterygopalatine ganglion is a parasympathetic ganglion found in the pterygopalatine fossa. It is one of four parasympathetic ganglia of the head and neck....
, and ciliary ganglion
Ciliary ganglion
The ciliary ganglion is a parasympathetic ganglion located in the posterior orbit. It measures 1–2 millimeters in diameter and contains approximately 2,500 neurons. Preganglionic axons from the Edinger-Westphal nucleus travel along the oculomotor nerve and form synapses with these cells...
).
It is occasionally absent.
Filaments
Filaments that pass through the ganglion without synapsing:- Nerve to tensor tympaniTensor tympaniThe tensor tympani, the larger of the two muscles of the tympanic cavity, is contained in the bony canal above the osseous portion of the auditory tube...
(coming from the trigeminal nerveTrigeminal nerveThe trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
motor nucleus) - Nerve to tensor veli palatini (coming from the trigeminal nerve motor nucleus)
- Nerve to levator veli palatiniLevator veli palatiniThe levator veli palatini is the elevator muscle of the soft palate in the human body. During swallowing, it contracts, elevating the soft palate to help prevent food from entering the nasopharynx...
(coming from facial nerve thought to run through the chorda tympaniChorda tympaniThe chorda tympani is a nerve that branches from the facial nerve inside the facial canal, just before the facial nerve exits the skull via the Stylomastoid foramen...
)
Branches of communication
Its sympathetic postganglionic fibers consists of a filament from the plexus surrounding the middle meningeal arteryMiddle meningeal artery
The middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery...
.
Preganglionic parasympathetic fibres reach it from the glossopharyngeal nerve (and possibly also from the facial nerve) via the lesser petrosal nerve
Lesser petrosal nerve
The lesser petrosal nerve consists of parasympathetic fibres. It leaves the tympanic plexus to synapse in the otic ganglion, and eventually provide parasympathetic innervation to the parotid gland....
continued from the tympanic plexus
Tympanic plexus
In the tympanic cavity, the tympanic nerve divides into branches which form the tympanic plexus. This plexus is located on the surface of the promontory.This tympanic plexus gives off:* the lesser petrosal nerve...
. Postganglionic parasympathetic fibres from the ganglion pass with the sympathetic fibres mainly in the auriculotemporal nerve (a branch of CN V3 -- the Mandibular branch of the Trigeminal Nerve
Trigeminal nerve
The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
) to supply the parotid gland. All postsynaptic parasympathetics will use some branch of the Trigeminal Nerve to get from one of four parasympatheic ganglia (Otic, Ciliary, Submandibular, and Peteryopalatine) to their destination in either smooth muscle or glandular tissue (secretomotor).
A slender filament (sphenoidal) ascends from it to the nerve of the Pterygoid canal
Pterygoid canal
The pterygoid canal is a passage in the skull leading from just anterior to the foramen lacerum in the middle cranial fossa to the pterygopalatine fossa.-Structure:...
, and a small branch connects it with the chorda tympani
Chorda tympani
The chorda tympani is a nerve that branches from the facial nerve inside the facial canal, just before the facial nerve exits the skull via the Stylomastoid foramen...
.
It is connected by two or three short filaments with the nerve to the Pterygoideus internus, from which it may obtain a motor, and possibly a sensory root.
Distribution
Its branches of distribution are: a filament to the Tensor tympaniTensor tympani
The tensor tympani, the larger of the two muscles of the tympanic cavity, is contained in the bony canal above the osseous portion of the auditory tube...
, and one to the Tensor veli palatini.
The former passes backward, lateral to the auditory tube; the latter arises from the ganglion, near the origin of the nerve to the Pterygoideus internus, and is directed forward.
The fibers of these nerves are, however, mainly derived from the nerve to the Pterygoideus internus.