The helicotrema (from el, ἕλιξ elixmeaning coil and rēmameaning hole) is the part of the cochlear labyrinth where the

scala tympani The tympanic duct or scala tympani is one of the perilymph-filled cavities in the inner ear of humans. It is separated from the cochlear duct by the basilar membrane, and it extends from the round window to the helicotrema, where it continues as ...

and the

scala vestibuli The vestibular duct or scala vestibuli is a perilymph-filled cavity inside the cochlea of the inner ear that conducts sound vibrations to the cochlear duct. It is separated from the cochlear duct by Reissner's membrane and extends from the ves ...

meet. It is the main component of the

cochlea The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory orga ...

r apex. The

hair cell Hair cells are the sensory receptors of both the auditory system and the vestibular system in the ears of all vertebrates, and in the lateral line organ of fishes. Through mechanotransduction, hair cells detect movement in their environment. ...

s near this area best detect low frequency sounds.

Structure

The helicotrema is a part of the cochlear labyrinth where the

and the

meet. It is the main component of the

r apex.

Function

The helicotrema connects the

and the

. This allows fluid to move between the two. It slightly impedes the travel of sound. The

s near this area best detect low frequency sounds.

Clinical significance

The

hair cells Hair cells are the sensory receptors of both the auditory system and the vestibular system in the ears of all vertebrates, and in the lateral line organ of fishes. Through mechanotransduction, hair cells detect movement in their environment. ...

near the helicotrema are at higher risk of

acoustic trauma Acoustic trauma is the sustainment of an injury to the eardrum as a result of a very loud noise. Its scope usually covers loud noises with a short duration, such as an explosion, gunshot or a burst of loud shouting. Quieter sounds that are concentr ...

than those in most other parts of the

. It is also important during ear surgery. When pressure is placed on the

perilymph Perilymph is an extracellular fluid located within the inner ear. It is found within the scala tympani and scala vestibuli of the cochlea. The ionic composition of perilymph is comparable to that of plasma and cerebrospinal fluid. The major cati ...

in the cochlea, it reduces pressure and prevents damage to the

organ of Corti The organ of Corti, or spiral organ, is the receptor organ for hearing and is located in the mammalian cochlea. This highly varied strip of epithelial cells allows for transduction of auditory signals into nerve impulses' action potential. Transd ...

References

External links

Histology
at Allegheny University of the Health Sciences
Diagram
at IUPUI {{Authority control Ear