lesser petrosal nerve
Sarah Parker
Updated on August 19, 2026
The secretomotor axons of the glossopharyngeal nerve originate in preganglionic neurons located in the salivatory nucleus in the upper medulla and lower pons. These axons follow the tympanic and lesser petrosal nerves and innervate the otic ganglion, located just medial to the mandibular branch of the trigeminal nerve.
Is lesser petrosal nerve a branch of Glossopharyngeal?
The lesser petrosal nerve carries preganglionic parasympathetic fibers to the parotid gland. It is considered a branch of the glossopharyngeal nerve although it receives contributions from two further sources 3: tympanic plexus: glossopharyngeal nerve via Jacobson’s nerve (main contribution)
Where does the lesser petrosal nerve arise?
After arising in the tympanic plexus, the lesser petrosal nerve passes forward and then through the hiatus for lesser petrosal nerve on the anterior surface of the petrous part of the temporal bone into the middle cranial fossa.
What are the four Petrosal nerves?
The greater palatine nerve that innervates the bony hard palate of the mouth. The lesser palatine that innervates the uvula, tonsils and soft palate. The nasal palatine and posterior nasal branches that innervate the nasal mucous membranes. The pharyngeal branch that innervates the glands and mucosa of the nasopharynx.
What does greater Petrosal innervate?
The greater petrosal nerve (or greater superficial petrosal nerve) is a nerve in the skull that branches from the facial nerve; it forms part of a chain of nerves that innervate the lacrimal gland. The preganglionic parasympathetic axons of this nerve synapse in the pterygopalatine ganglion.
What does greater petrosal nerve do?
The greater petrosal nerve or superficial petrosal nerve is a branch of the nervus intermedius (nerve of Wrisberg) that carries parasympathetic, taste, and sensory fibers of the facial cranial nerve (CN VII).
What is Jacobson nerve?
Jacobson’s nerve is a tympanic branch of the glossopharyngeal nerve, arising from its inferior ganglion. It enters the middle ear cavity through the inferior tympanic canaliculus, runs in a canal on the cochlear promontory and provides the main sensory innervation to the mucosa of the mesotympanum and Eustachian tube.
What is geniculate ganglion?
The geniculate ganglion is a sensory ganglion of the facial nerve (CN VII). It contains the cell bodies of the fibers responsible for conducting taste sensation from the anterior two-thirds of the tongue.
What muscles does the glossopharyngeal nerve innervate?
The axons that belong to the glossopharyngeal nerve provide motor innervation to the stylopharyngeus muscle and the superior pharyngeal constrictor muscle.
Where does deep petrosal nerve come from?
The deep petrosal nerve is a branch from the internal carotid plexus. The plexus is located on the lateral side of the internal carotid as it courses superiorly. The deep petrosal enters the skull through the carotid canal with the internal carotid artery.
What is external petrosal nerve?
The external petrosal nerve is one of the three branches from the geniculate ganglion. It carries sympathetic fibers from the sympathetic plexus surrounding the middle meningeal artery, coursing extradurally laterally to the greater and lesser petrosal nerves on the petrous ridge’s anterior surface 3.
What passes through the foramen ovale?
The following structures pass through foramen ovale: mandibular nerve (a branch of the trigeminal nerve). accessory meningeal artery. lesser petrosal nerve (a branch of the glossopharyngeal nerve).
How many Petrosal nerves are there?
Six petrosal nerves have been described: exter- nal, deep, small deep, smallest deep, greater, and lesser. One of these is a branch of the facial nerve, one is a branch of the glossopharyngeal nerve, and four are derived from sympathetic fibers.
What is auriculotemporal nerve?
Introduction. The auriculotemporal nerve is a tributary of the mandibular division of cranial nerve five, the trigeminal nerve. It contains sensory, vasomotor, and parasympathetic fibers.
What is nervus intermedius?
The nervus intermedius is the sensory and parasympathetic division of the facial nerve. It contains visceral afferent fibers coming from the taste buds of the anterior two-thirds of the tongue and mucous membranes of the pharynx, nose, and palate.
What’s the cause of Bells Palsy?
The cause of Bell’s palsy is unknown but is thought to be caused by inflammation affecting the body’s immune system. It is associated with other conditions such as diabetes. Symptoms of facial weakness or paralysis get worse over the first few days and start to improve in about 2 weeks.
What nerve supplies Stapedius?
The nerve to stapedius arises from the facial nerve to supply the stapedius muscle. The branch is given off in the facial nerve’s mastoid segment, as it passes posterior to the pyramidal process. Damage to this branch with resulting paralysis of stapedius leads to hypersensitivity to loud noises (hyperacusis).
Which is called nerve of Wrisberg?
The nervus intermedius, also known as intermediate nerve of Wrisberg, is a part of the facial nerve (CN VII) which contains somatic sensory, special sensory, and visceral motor (secretomotor) fibers 1.
What muscles does the glossopharyngeal nerve innervate?
The axons that belong to the glossopharyngeal nerve provide motor innervation to the stylopharyngeus muscle and the superior pharyngeal constrictor muscle.
What does lacrimal nerve do?
Function. The lacrimal nerve provides sensory innervation to the lacrimal gland, conjunctiva of the lateral upper eyelid and superior fornix, the skin of the lateral forehead, scalp and lateral upper eyelid.
What is external petrosal nerve?
The external petrosal nerve is one of the three branches from the geniculate ganglion. It carries sympathetic fibers from the sympathetic plexus surrounding the middle meningeal artery, coursing extradurally laterally to the greater and lesser petrosal nerves on the petrous ridge’s anterior surface 3.
Where does deep petrosal nerve come from?
The deep petrosal nerve is a branch from the internal carotid plexus. The plexus is located on the lateral side of the internal carotid as it courses superiorly. The deep petrosal enters the skull through the carotid canal with the internal carotid artery.
