Table 2.

Principal characteristics of inner ear malformations (see references 17,19,23). FN: facial nerve; CAVD: cochlear aplasia with a dilated vestibule; EVA: enlarged vestibular aqueduct; HA: hearing aid; CI: cochlear implantation; ABI: auditory brainstem implantation

Inner ear malformations	Imaging findings	Facial nerve routes anomaly	Treatment
Complete labyrinthine aplasia	Absent labyrinth (cochlea, SCCs and vestibule)	Yes	ABI
Rudimentary otocyst	Millimetric otic capsule residue	Yes	ABI
Cochlear aplasia	Absent cochlea with different degree of representation of SCCs and vestibule (divided in “CA with normal labyrinth” and “CAVD”)	Yes	ABI
Common cavity	Cochlea and vestibule have a single cavity	Yes	CI or ABI
Cochlear hypoplasia	Small size of the cochlea with various internal structural abnormalities (four types [19])	Yes	HA, CI or ABI
Incomplete partition I	Cochlea with cystic appearance	Possible	CI or ABI
Incomplete partition II	Cystic appearance of the cochlear apex associated with a minimally dilated vestibule and enlarged vestibular aqueduct	No	HA or CI
Incomplete partition III	Modiolus absent, interscalar septa present	Yes	HA or CI
EVA	EVA with normal cochlea	No	HA or CI