Promontory of the tympanic cavity
Encyclopedia
The promontory of the tympanic cavity
, better known as the cochlear promontory is a rounded hollow prominence, formed by the projection outward of the first turn of the cochlea
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It is placed between the fenestrae
, and is furrowed on its surface by small grooves, for the lodgement of branches of the tympanic plexus
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A minute spicule of bone frequently connects the promontory to the pyramidal eminence
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Tympanic cavity
The tympanic cavity is a small cavity surrounding the bones of the middle ear.It is formed from the tubotympanic recess, an expansion of the first pharyngeal pouch....
, better known as the cochlear promontory is a rounded hollow prominence, formed by the projection outward of the first turn of the cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
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It is placed between the fenestrae
Fenestrae
Fenestræ is a Latin word that means "window".* In histology, fenestræ are small pores in endothelial cells that allow for rapid exchange of molecules between sinusoid blood vessels and surrounding tissue...
, and is furrowed on its surface by small grooves, for the lodgement of branches of 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...
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A minute spicule of bone frequently connects the promontory to the pyramidal eminence
Pyramidal eminence
The pyramidal eminence is situated immediately behind the fenestra vestibuli, and in front of the vertical portion of the facial canal; it is hollow, and contains the Stapedius muscle; its summit projects forward toward the fenestra vestibuli, and is pierced by a small aperture which transmits the...
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