Tympanic Plexus

	Tympanic Plexus In the tympanic cavity, the tympanic nerve (a branch of CN IX) divides into branches which, along with sympathetic fibres from the carotid plexus, form the tympanic plexus. This plexus is located on the surface of the promontory. This tympanic plexus branches into: * the lesser petrosal nerve The lesser petrosal nerve (also known as the small superficial petrosal nerve) is the general visceral efferent (GVE) component of the glossopharyngeal nerve (CN IX), carrying parasympathetic preganglionic fibers from the tympanic plexus to the pa ... (preganglionic parasympathetic axons to otic ganglion) * sensory branches to the tympanic cavity The branches to the tympanic cavity provide sensory innervation to the mucosa of the tympanic cavity and the internal surface of the tympanic membrane. The cell bodies of these neurons are found in the superior ganglion of the glossopharyngeal nerve. References External links * () * {{Authority control Nerve plexus Glossopharyngeal nerv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Caroticotympanic Nerves The caroticotympanic nerves are nerves which supply the eardrum ("tympanum") and carotid canal. They are the postganglionic sympathetic fibers from internal carotid plexus which enter the tympanic cavity via the caroticotympanic artery. These fibers join the tympanic plexus which are located on the surface of the Promontory of tympanic cavity, promontory. See also * Caroticotympanic arteries Auditory system Nerves {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Tympanic Nerve The tympanic nerve (Jacobson’s nerve) is a branch of the glossopharyngeal nerve found near the ear. It gives sensation to the middle ear, the Eustachian tube, the parotid gland, and mastoid air cells. It gives parasympathetic to supply to the parotid gland via the otic ganglion and the auriculotemporal nerve. Structure The tympanic nerve arises from the inferior ganglion of the glossopharyngeal nerve. It ascends to the tympanic cavity through a small canal, the inferior tympanic canaliculus, on the under surface of the petrous portion of the temporal bone on the ridge which separates the carotid canal from the jugular fossa. In the tympanic cavity, it divides into branches which form the tympanic plexus and are contained in grooves upon the surface of the promontory. The tympanic nerve contains sensory axons to the middle ear, including the internal surface of the tympanic membrane. Their cell bodies are found in the superior ganglion of the glossopharyngeal nerve. It al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Tympanic Cavity The tympanic cavity is a small cavity surrounding the bones of the middle ear. Within it sit the ossicles, three small bones that transmit vibrations used in the detection of sound. Structure On its lateral surface, it abuts the external auditory meatus ear canal from which it is separated by the tympanic membrane (eardrum). Walls The tympanic cavity is bounded by: * Facing the inner ear, the medial wall (or ''labyrinthic wall'', ''labyrinthine wall'') is vertical, and has the oval window and round window, the promontory, and the prominence of the facial canal. * Facing the outer ear, the lateral wall (or ''membranous wall''), is formed mainly by the tympanic membrane, partly by the ring of bone into which this membrane is inserted. This ring of bone is incomplete at its upper part, forming a notch (notch of Rivinus), close to which are three small apertures: the "iter chordæ posterius", the petrotympanic fissure, and the "iter chordæ anterius". The iter chordæ posterius (aper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	CN IX The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. Being a mixed nerve (sensorimotor), it carries afferent sensory and efferent motor information. The motor division of the glossopharyngeal nerve is derived from the basal plate of the embryonic medulla oblongata, whereas the sensory division originates from the cranial neural crest. Structure From the anterior portion of the medulla oblongata, the glossopharyngeal nerve passes laterally across or below the flocculus, and leaves the skull through the central part of the jugular foramen. From the superior and inferior ganglia in jugular foramen, it has its own sheath of dura mater. The inferior ganglion on the inferior surface of petrous part of temporal is related with a triangular depression into which the aqueduct of cochlea opens. On the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Promontory Of The Tympanic Cavity The promontory of the tympanic cavity, also known as the cochlear promontory is a rounded hollow prominence, formed by the projection outward of the first turn of the cochlea. It is placed between the oval window and the round window, and is furrowed on its surface by small grooves, for the lodgement of branches of the tympanic plexus. A minute spicule of bone frequently connects the promontory to the pyramidal eminence The pyramidal eminence (pyramid) is a conical projection in the middle ear. It is situated immediately behind the fenestra vestibuli (oval window), and in front of the vertical portion of the facial canal; it is hollow, and contains the stapedi .... Additional images File:Gray913.png, Coronal section of right temporal bone. File:Gray914.png, The medial wall and part of the posterior and anterior walls of the right tympanic cavity, lateral view. References External links * Ear {{Musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Lesser Petrosal Nerve The lesser petrosal nerve (also known as the small superficial petrosal nerve) is the general visceral efferent (GVE) component of the glossopharyngeal nerve (CN IX), carrying parasympathetic preganglionic fibers from the tympanic plexus to the parotid gland. It synapses in the otic ganglion, from where the postganglionic fibers emerge. Structure 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. It travels across the floor of the middle cranial fossa, then exits the skull via canaliculus innominatus to reach the infratemporal fossa. The fibres synapse in the otic ganglion, and post-ganglionic fibres then travel briefly with the auriculotemporal nerve (a branch of V3) before entering the body of the parotid gland. The lesser petrosal nerve will distribute its parasympathetic post-ganglionic (GVE) fibers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Superior Ganglion Of Glossopharyngeal Nerve The superior ganglion of the glossopharyngeal nerve is a sensory ganglion of the peripheral nervous system. It is located within the jugular foramen where the glossopharyngeal nerve exits the skull. It is smaller than and superior to the inferior ganglion of the glossopharyngeal nerve. The neurons in the superior ganglion of the glossopharyngeal nerve provide sensory innervation to the middle ear and the internal surface of the tympanic membrane. The axons of these neurons branch from the glossopharyngeal nerve at the level of the inferior ganglion and form the tympanic nerve along with the preganglionic parasympathetic axons from the inferior salivatory nucleus. The tympanic nerve then travels through the inferior tympanic canaliculus to the tympanic cavity forming the tympanic plexus. From here the sensory axons provide innervation of the middle ear and internal surface of the tympanic membrane. The parasympathetic axons branch from the tympanic plexus as the lesser petrosal ner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Nerve Plexus A nerve plexus is a plexus (branching network) of intersecting nerves. A nerve plexus is composed of afferent and efferent fibers that arise from the merging of the anterior rami of spinal nerves and blood vessels. There are five spinal nerve plexuses, except in the thoracic region, as well as other forms of autonomic plexuses, many of which are a part of the enteric nervous system. The nerves that arise from the plexuses have both sensory and motor functions. These functions include muscle contraction, the maintenance of body coordination and control, and the reaction to sensations such as heat, cold, pain, and pressure. There are several plexuses in the body, including: Spinal Plexuses * Cervical plexus - serves the head, neck and shoulders Brachial plexus - serves the chest, shoulders, arms and hands Lumbosacral plexus *Lumbar plexus - serves the back, abdomen, groin, thighs, knees, and calves Subsartorial plexus - below the sartorius muscle of thigh Sacral plex ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]