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Inferior Tympanic Canaliculus
The inferior tympanic canaliculus is a small passage of the tympanic branch of the glossopharyngeal nerve and inferior tympanic artery. In the bony ridge dividing the carotid canal from the jugular fossa is the small inferior tympanic canaliculus. The inferior tympanic canaliculus is near the fossula petrosa which houses inferior ganglion of glossopharyngeal nerve/petrous ganglion from which the 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 ... arises. References Foramina of the skull {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Bone
The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. The lower seven cranial nerves and the major vessels to and from the brain traverse the temporal bone. Structure The temporal bone consists of four parts— the squamous, mastoid, petrous and tympanic parts. The squamous part is the largest and most superiorly positioned relative to the rest of the bone. The zygomatic process is a long, arched process projecting from the lower region of the squamous part and it articulates with the zygomatic bone. Posteroinferior to the squamous is the mastoid part. Fused with the squamous and mastoid parts and between the sphenoid and occipital bones lies the petrous part, which is shaped like a pyramid. The tympanic part is relatively small and lies inferior to the squamous part, anterior to the mast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tympanic Branch
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 also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossopharyngeal Nerve
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 oblongata, 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 (neural tube), 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 (cerebellar), 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 tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Tympanic Artery
The inferior tympanic artery is a small branch of the ascending pharyngeal artery. It is a small branch which passes through a minute foramen in the petrous portion of the temporal bone which is called tympanic canaliculus or inferior tympanic canaliculus, in company with the tympanic branch of the glossopharyngeal nerve, to supply the medial wall of the 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 ... and anastomose with the other tympanic arteries. Clinical Significance In the case of a missing or underdeveloped cervical ICA, the Inferior tympanic artery can provide collateral ICA circulation by reversing flow of the caroticotympanic artery (embryologic hyoid artery). This can result in pulsatile tinnitus. The resulting Aberrant Carotid artery can mimic ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carotid Canal
The carotid canal is a passageway in the temporal bone of the skull through which the internal carotid artery enters the middle cranial fossa from the neck. Structure The carotid canal is located within the middle cranial fossa, at the petrous part of the temporal bone. Anteriorly, it is limited by posterior margin of the greater wing of sphenoid bone. Posteromedially, it is limited by basilar part of occipital bone. It is divided in three parts, namely, ascending petrous, transverse petrous, and ascending cavernous parts. The carotid canal has two openings, namely internal and external openings. The internal opening is situated laterally to foramen lacerum. The external opening of the carotid canal is located posterolaterally to the foramen lacerum. Both internal and external openings of the carotid canal lies anterior to the jugular foramen, where the latter is located inside the posterior cranial fossa. The carotid canal is separated from middle ear and inner ear by a thin pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jugular Fossa
The jugular fossa is a deep depression in the inferior part of the temporal bone at the base of the skull. It lodges the bulb of the internal jugular vein. Structure The jugular fossa is located in the temporal bone, posterior to the carotid canal and the cochlear aqueduct. In the bony ridge dividing the carotid canal from the jugular fossa is the small inferior tympanic canaliculus for the passage of the tympanic branch of the glossopharyngeal nerve. In the lateral part of the jugular fossa is the mastoid canaliculus for the entrance of the auricular branch of the vagus nerve. Behind the jugular fossa is a quadrilateral area, the jugular surface, covered with cartilage in the fresh state, and articulating with the jugular process of the occipital bone. Variation The jugular fossa has variable depth and size in different skulls. Function The jugular fossa lodges the bulb of the internal jugular vein. Clinical significance Abnormally shaped jugular fossae may cause ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Ganglion Of Glossopharyngeal Nerve
The inferior ganglion of the glossopharyngeal nerve (petrosal ganglion) is a sensory ganglion. It is larger than and inferior to the superior ganglion of the glossopharyngeal nerve. It is located within the jugular foramen. The pseudounipolar neurons of the inferior ganglion of the glossopharyngeal nerve provide sensory innervation to areas around the tongue and pharynx. More specifically: # innervation of taste buds on the posterior 1/3 of tongue # general sensory innervation of posterior 1/3 of tongue, soft palate, palatine tonsils, upper pharynx and Eustachian tubes # innervation of baroreceptor cells in the carotid sinus # innervation of glomus type I chemoreceptor cells in the carotid body The central processes of the neurons which provide taste sensation synapse in the rostral portion of the solitary nucleus (also called the gustatory nucleus). The central processes of the neurons which provide general sensory information synapse in the spinal trigeminal nucleus. Final ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrous Ganglion
The inferior ganglion of the glossopharyngeal nerve (petrosal ganglion) is a sensory ganglion. It is larger than and inferior to the superior ganglion of the glossopharyngeal nerve. It is located within the jugular foramen. The pseudounipolar neurons of the inferior ganglion of the glossopharyngeal nerve provide sensory innervation to areas around the tongue and pharynx. More specifically: # innervation of taste buds on the posterior 1/3 of tongue # general sensory innervation of posterior 1/3 of tongue, soft palate, palatine tonsils, upper pharynx and Eustachian tubes # innervation of baroreceptor cells in the carotid sinus # innervation of glomus type I chemoreceptor cells in the carotid body The central processes of the neurons which provide taste sensation synapse in the rostral portion of the solitary nucleus (also called the gustatory nucleus). The central processes of the neurons which provide general sensory information synapse in the spinal trigeminal nucleus. Finally ... [...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] |