answersLogoWhite

0

An aditus is the entrance to a cavity or channel.

User Avatar

Wiki User

10y ago

What else can I help you with?

Related Questions

What has the author Sylvester Rattray written?

Sylvester Rattray has written: 'Aditus novus ad occultas sympathiae et antipathiae causas inveniendas' -- subject(s): Medicine, Early works to 1800, Sympathy (Physiology)


What has the author Johann Andreas Danz written?

Johann Andreas Danz has written: 'Ioh. Andr. Danzii ... sive compendium grammaticae Ebraeo -Chaldaicae' -- subject(s): Grammar, Hebrew language, Aramaic language 'I.A. Danzii ... sive interpretis Ebraeo-Chaldaei synopsis' -- subject(s): Grammar, Hebrew language, Aramaic language 'Aditus Syriae Reclusus compendiose ducens ad plenam linguae Syriacae Antiochenae seu Maroniticae cognitionem' -- subject(s): Syriac language, Grammar


What are the functions of the mastoid air cells?

The mastoid air cells of the temporal bones are an interconnected network of small sinus cavities which communicate with the middle ear via the aditus ad antrum superiorly. The middle ear, which does not communicate with the external auditory canal due to presence of a (normally) intact tympanic membrane (the "ear drum"), depends on the additional compliance of the air-filled mastoid air cells in order to allow the tympanic membrane to move in response to sound waves (= changes in air pressure). The tympanic membrane needs to be able to move freely in order to convert external pressure changes into movement of the ossicular chain of the middle ear, which in turn conveys that motion to the membrane-covered oval window of the fluid-filled cochlea. The cochlea is responsible for converting that movement into nerve signals to send to the brain for interpretation. Interestingly, the cochlea has a second small membrane-covered opening, the round window, to enable the fluid to move in the cochlea secondary to action of the ossicles on the oval window, similar to the function of the mastoid air cells in allowing the tympanic membrane to move in response to changes in external air pressure. If the mastoid air cells are absent or fluid filled, there is less compliance in the system, decreasing the ability for the tympanic membrane to move and transmit sound, decreasing auditory acuity. In addition, the mastoid air cells provide secretions that slowly travel from the mastoid air cells through the middle ear and into the posterior nasopharynx by way of the eustachian tubes in order to keep the middle ear clear of debris. The eustachian tubes are the structures that allow you to "pop" your ears in response to pressure changes, by equalizing pressures in the middle ear with the external environment through transmission of air from your nose and mouth. This is also the primary reason that people (and especially children, with their smaller eustachian tubes) almost always have fluid in their middle ears when they are suffering from upper respiratory tract infections ... the upper respiratory tract is contiguous with the middle ear by way of the eustachian tubes. N.B: The mastoid air cells are not "air bags" or "crumple zones" to protect the brain from injury; severe temporal bone injury carries significant morbidity (hearing loss, facial nerve paralysis, chronic infections, vascular injury of the carotid and internal jugular veins) and mortality, and the mastoid air cells themselves are highly protected with thick overlying cortical bone.


Which joint enables you to move your arms free?

The shoulder joint enables free movement of the arms in multiple directions. It is a ball-and-socket joint that allows for a wide range of motion, including flexion, extension, abduction, adduction, and rotation of the arms.