Role of CT and MRI in the preoperative evaluation of auditory brainstem implantation in patients with congenital inner ear pathology.
OBJECTIVE
The purpose of this study was to evaluate the reliability of computed tomography (CT) and magnetic resonance imaging (MRI) in characterising cochlear nerve anomalies in auditory brainstem implant candidates with congenital hearing loss.


METHODS
Seventeen patients affected by congenital sensorineural hearing loss were examined by CT and MRI. Inner ear malformations eligible for auditory brainstem implants were classified according to the Casselman classification. All patients subsequently received auditory brainstem implants.


RESULTS
Suspected congenital anomalies were confirmed by CT and MRI in all 17 patients. There were 5/17 bilateral cochlear nerve aplasias and 12/17 cochleovestibular anomalies. Of these, 5/12 patients had a common cochleovestibular cavity, 2/12 had bilateral cochlear aplasia and cochlear nerve agenesis, 1/12 had type I incomplete partition, 2/12 had type II incomplete partition and 2/12 had cochlear hypoplasia.


CONCLUSIONS
Preoperative CT and MRI assessment of patients with sensorineural hearing loss is reliable. MRI provided additional information, identifying the possible absence of cochlear nerve and excluding other central nervous system (CNS) diseases.
Cerini
R
R
Istituto di Radiologia, Università di Verona, Policlinico G.B. Rossi, Verona, Italy. roberto.cerini@azosp.vr.it
Faccioli
N
N
Cicconi
D
D
Schenal
G
G
Cugini
C
C
Giarbini
N
N
Colletti
V
V
Pozzi Mucelli
R
R
D000293:Adolescent; D000328:Adult; D038263:Auditory Brain Stem Implantation; D002648:Child; D002675:Child, Preschool; D003054:Cochlear Implants; D003056:Cochlear Nerve / Q000002:abnormalities* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011300:Preoperative Care; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed