Structure and Course of the Lesser Petrosal Nerve
- The lesser petrosal nerve is also known as the small superficial petrosal nerve.
- It is a general visceral efferent (GVE) nerve.
- It conveys pre-ganglionic parasympathetic secretomotor fibers for the parotid gland.
- The nerve passes through the petrous part of the temporal bone.
- It exits the cranial cavity through its own canaliculus.
- The nucleus of the lesser petrosal nerve is the inferior salivatory nucleus.
- It is considered a continuation of the tympanic nerve.
- After arising in the tympanic plexus, it passes through the anterior surface of the petrous part of the temporal bone.
- The nerve runs across the floor of the middle cranial fossa.
- It exits the skull via the canaliculus innominatus and enters the infratemporal fossa.
Synapse, Distribution, and Innervation of the Lesser Petrosal Nerve
- The fibers of the lesser petrosal nerve synapse at the otic ganglion.
- Post-ganglionic fibers then travel along with the auriculotemporal nerve before entering the parotid gland.
- The nerve distributes its post-ganglionic parasympathetic fibers to the parotid gland.
- This distribution occurs via the intraparotid plexus.
- The intraparotid plexus consists of branches from the facial nerve in the parotid gland.
- The lesser petrosal nerve is related to the tympanic nerve.
- It is also related to the glossopharyngeal nerve, specifically its visceral motor component.
- These nerves play a role in the innervation of the parotid gland.
References and External Links
- The information in this article is sourced from the 20th edition of Gray's Anatomy.
- Additional references include 'Gray's Anatomy: The Anatomical Basis of Clinical Practice' by Susan Standring and 'Last's Anatomy' by Chummy S. Sinnatamby.
- A diagram of the lesser petrosal nerve can be found on the website 'The Anatomy Lesson' by Wesley Norman.
- The course of the lesser petrosal nerve is discussed in an article published in Neurosurgery.
- More information on cranial nerves, including the lesser petrosal nerve, can be found on the website of Yale School of Medicine.