abnormal membranous labyrinth morphology abnormal vestibular labyrinth morphology MP:0004427 MPheno.ontology abnormal labyrinthus vestibularis abnormal vestibular organ morphology any structural anomaly in the portion of the membranous labyrinth concerned with the sense of equilibration (vs. the cochlear labyrinth, which is concerned with the sense of hearing) and innervated by the vestibular nerve; it is located within the semicircular canals and vestibule of the bony labyrinth, and consists of the utricle, saccule, and the semicircular, utriculosaccular, and endolymphatic ducts