Cochlear duct
Ductus cochlearis (scala media)
Sensory (eye & ear)OrgansHeadLeft and right
View left in 3D View right in 3D
- What it is
- The membranous middle channel, triangular in cross-section, bounded by Reissner's membrane above, the basilar membrane below and the stria vascularis on the outer wall. It is filled with potassium-rich endolymph and carries the organ of Corti on its floor.
- Function
- Houses the sensory organ of Corti and maintains the +80 mV endocochlear potential that powers hair-cell transduction.
- Size
- About 35 mm long following the spiral; endolymph volume about 2 microlitres.
- Clinical note
- Swelling of this duct (endolymphatic hydrops) underlies Meniere's disease: attacks of vertigo, tinnitus and fluctuating hearing loss.