Utricle
Utriculus
Sensory (eye & ear)OrgansHeadLeft and right
View left in 3D View right in 3D
- What it is
- An oblong membranous sac in the upper back part of the vestibule into which all three semicircular ducts open. On its floor lies a horizontal sensory patch (macula) covered by a gelatinous membrane studded with calcium-carbonate crystals, the otoconia.
- Function
- Senses horizontal linear acceleration and tilt of the head relative to gravity.
- Size
- About 3-4 mm long and 2 mm across.
- Clinical note
- Otoconia that break loose and fall into the posterior semicircular canal cause benign paroxysmal positional vertigo (BPPV), treated with the Epley repositioning manoeuvre.