Aplasia of the cochlea: radiologic assessment and options for hearing rehabilitation.
OBJECTIVE
Hearing rehabilitation of patients with severe inner ear malformations remains controversial. Our objective was to describe the radiologic findings of aplasia of the cochlea (AC) and evaluate the existing therapeutic options in such patients.


METHODS
Retrospective cohort study.


METHODS
Tertiary referral center.


METHODS
Pediatric and adult patients with AC evaluated at our institution from 1995 to 2010.


METHODS
The precise radiologic findings were identified using high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) scans of the inner ear. In cases of auditory implantation on the AC side, the achieved outcome was recorded using categories of auditory performance (CAP). Related surgical aspects were analyzed.


RESULTS
Twenty-three patients (28 ears) with AC were found. In 5 patients AC was bilateral. The remaining unilateral cases had contralateral normal ears (2 patients), cochlea hypoplasia (5 patients), common cavity (6 patients), incomplete partition Type I (4 patients), and atresia of the internal auditory canal (1 patient). Four patients (3 bilateral, 1 unilateral ACs) were treated with cochlear implants in ears with AC, and 1 patient underwent auditory brainstem implantation. All implanted patients achieved speech perception with limited vocabulary (CAP scores between 4 and 5).


CONCLUSIONS
AC is defined as the total absence of the cochlea, with a present, although malformed, vestibule. Although a distinct auditory nerve was not seen in these cases of AC, results following cochlear implantation suggest functional cochlear nerve fibers in the remaining dysplastic inner ear structures. In selected cases, cochlear implantation may be a reasonable option for the habilitation of deafness associated with AC.
Department of Otolaryngology, , Hannover Medical School, Hannover, Germany.
Georgios
G
Kontorinis
Friedrich
F
Goetz
Alexandros
A
Giourgas
Heinrich
H
Lanfermann
Thomas
T
Lenarz
Anja M
AM
Giesemann
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003051:Cochlea / Q000002:abnormalities* / Q000000981:diagnostic imaging* / Q000601:surgery; D019929:Cochlear Implantation; D003054:Cochlear Implants; D015331:Cohort Studies; D004424:Ear Canal / Q000002:abnormalities; D005158:Facial Paralysis / Q000209:etiology; D005260:Female; D007839:Functional Laterality; D006311:Hearing Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D013506:Otologic Surgical Procedures; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult