Cochlear implantation in cases with incomplete partition type III (X-linked anomaly).

Incomplete partition-type III anomaly (X-linked deformity) is no common finding in a prospective candidate for cochlear implantation. In this paper, the problems about the cochlear implantation in cases with incomplete partition-type III anomaly (X-linked deformity) and profound sensorineural hearing loss is discussed. High-resolution multidedector computed tomography (MDCT) and magnetic resonance imaging were performed preoperatively in all patients. MDCT revealed that there was bulbous dilatation at the lateral ends of internal auditory canals (IAC) in all patients. There were also enlargements of labyrinthine segments of facial and superior vestibular nerve canals. Patients with the basal turns of cochlea incompletely separated from IAC were also presented. Patients with IP-type III (X-linked deformity) and profound SNHL were implanted. Standard transmastoid-facial recess approach was used and cerebrospinal gusher was encountered after the cochleostomy in all cases. Postoperative performance was very good in all patients. Two patients had complications, which are facial nerve stimulation and device failure. Both patients were reimplanted. Cochlear implantation is a good choice in the patients with IP-type III. However, this anomaly may have special potential risk than the other inner ear abnormalities. Therefore, the surgeon should be aware of them and must be ready to inform the patient and parents.