Search results
Results from the WOW.Com Content Network
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 vestibular duct .
A cross section of the cochlea will reveal an anatomical structure with three main chambers (scala vestibuli, scala media, and scala tympani). [5] At the apical end of the cochlea, at an opening known as the helicotrema, the scala vestibuli merges with the scala tympani.
The first half of the duct is now referred to as the scala vestibuli, while the second half, which includes the basilar membrane, is called the scala tympani. As a result of this increase in length, the basilar membrane and papilla are both extended, with the latter developing into the organ of Corti , while the lagena is now called the ...
As the cochlear duct's mesenchyme begins to differentiate, three cavities are formed: the scala vestibuli, the scala tympani and the scala media. [18] [21] Both the scala vestibuli and the scala tympani contain an extracellular fluid called perilymph, while the scala media contains endolymph. [21]
The cochlea has three fluid-filled sections (i.e. the scala media, scala tympani and scala vestibuli), and supports a fluid wave driven by pressure across the basilar membrane separating two of the sections. Strikingly, one section, called the cochlear duct or scala media, contains endolymph. The organ of Corti is located in this duct on the ...
The organ of Corti, surrounded in potassium-rich fluid endolymph, lies on the basilar membrane at the base of the scala media. Under the organ of Corti is the scala tympani and above it, the scala vestibuli. Both structures exist in a low potassium fluid called perilymph. [8]
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 cation in perilymph is sodium, with the values of sodium and potassium concentration in the perilymph being 138 mM and 6.9 mM, respectively. [1]
The helicotrema (from Greek: ἕλιξ [helix] meaning coil and τρη̂μα [trēma] meaning hole) is the part of the cochlear labyrinth where the scala tympani and the scala vestibuli meet. It is the main component of the cochlear apex. The hair cells near this area best detect low frequency sounds.