ethmoid labyrinth

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Related to ethmoid labyrinth: lacrimal bone, ethmoid sinus, vomer, sphenoid, Perpendicular plate, crista galli, Vomer bone


the inner ear, consisting of the vestibule, cochlea, and semicircular canals. The cochlea is concerned with hearing and the vestibule and semicircular canals with the sense of equilibrium. (See also color plates.) adj., adj labyrin´thine. 

The bony portion of the labyrinth (osseous labyrinth) is composed of a series of canals tunneled out of the temporal bone. Inside the osseous labyrinth is the membranous labyrinth, which conforms to the general shape of the osseous labyrinth but is much smaller. A fluid called perilymph fills the space (perilymphatic space) between the osseous and membranous labyrinths. Fluid inside the membranous labyrinth is called endolymph. These fluids play an important role in the transmission of sound waves and the maintenance of body balance. The membranous labyrinth is divided into two parts: the cochlear labyrinth, which includes the perilymphatic space and the cochlear duct, and the vestibular labyrinth, which includes the utricle, saccule, and semicircular canals.

Disorders of the inner ear, such as labyrinthitis and meniere's disease, are characterized by episodes of dizziness, tinnitus, and hearing loss.
ethmoid labyrinth (ethmoidal labyrinth) either of the paired lateral masses of the ethmoid bone, consisting of numerous thin-walled cellular cavities, the ethmoidal cells.

eth·moid lab·y·rinth

(eth'moyd lab'i-rinth)
A mass of air cells with thin bony walls forming part of the lateral wall of the nasal cavity; the cells are arranged in three groups, anterior, middle, and posterior, and are closed laterally by the orbital plate, which forms part of the wall of the orbit.
References in periodicals archive ?
Extensive knowledge of sinonasal anatomy, particularly of the ethmoid labyrinth and its surrounding structures, was essential when performing total intranasal ethmoidectomy before the development of FESS.
The presence of clefts in the ethmoid labyrinth instead of discrete ostia, as is seen in the maxillary and sphenoid sinuses, and the ill-defined junction between ethmoid and nasal mucosa make it difficult to precisely identify the site of origin of an ethmoid polyp.
The turbinate had a fibro-osseous consistency, as did the tissue in the ethmoid labyrinth, which was carefully dissected with the help of a computer-aided guidance system.