Cochlear Implantations for Children with Congenital Inner Ear Malformation Ryuta Kamekura, Tomoko Shintani, Akiko Okazaki, Aya Kawabatao, Kae Kitagawa and Tetsuo Himi Department of Otolaryngology, Sapporo Medical University Hokkaido Prefectural Rehabiritation Center for Handicapped Children, Sapporo Unit From April 1996 through November 2003 we had four cases of cochlear implant for children with congenital inner ear malformation. We reported on each operation technique used and the postoperative hearing level of these four cases. Three these cases had the Mondini deformity. The other had a common cavity deformity. CSF gusher in cochleostomy occurred in one of the three Mondini deformity cases. It is important to bear in mind abnormalities in the intratympanic course of the facial nerve, constriction of internal auditory meatus, cochlear nerve defect, CSF gusher in cochleostomy and meningitis after cochlear implantation, when the operation is being performed on children with inner ear malformation. Key words: cochlear implantation, inner ear malformation, common cavity deformity, Mondini deformity, CSF gusher

tection with the cochlear implant in five ears of four children with congenital malformations of the cochlea. Laryngoscope 97 (supple 40): 15-17, 1987. 4) Slattery WH III, Luxford WM, House WF: Cochlear implantation in the congenitally malformed cochrea. Laryngoscope 105: 1184-1187, 1995. 5) Tucci DL, Telian SA, Zimmerman-Philips S, et al.: Cochlear implantation in patients with cochlear mal- Arch Otolaryngol Head Neck Surg 121: formations. 833-838, 1995. 6) McElveen JT, Carrasco VN, Miyamoto RT, et al.: Cochlear implantation in common cavity malformations using a transmastoid labyrinthotomy approach. Laryngoscope 107: 1032-1036, 1997. 7) Hoffman RA, Downey LL, Waltzman SB, et al.: Cochlear implantation in children with cochlear malformations. Am J Otol 18: 184-187, 1997. 8) Woolley AL, Jenison V, Stroer BS, et al.: Cochlear implantation in children with inner ear malformations. Ann Otol Rhino! Laryngol 107: 492-500, 1998. 1) Jensen S: Malformations of the inner ear in deaf children. Acta Radiol 286 (Suppl): 1-97, 1969. 2) Jackler RK, Luxford WM, House WF: Congenital malformations of the inner ear: a classification based on embryogenesis. Laryngoscope 97 (supple 40): 2 14, 1987. 3) Jackler RK, Luxford WM, House WF: Sound de- 13) Antonelli PJ, Varela AE, Mancuso AA: Diagnostic yield of high-resolution computed tomography for pediatric sensorineural hearing loss, Laryngoscope 109: 1642-1647, 1999. 15) Hoffman RA, Cohen NL: Complications of cochlear implant surgery. Ann Otol Rhinol Laryngol 104 (suppl 166): 420-422, 1995. 16) Schuknecht HF: Mondini dysplasia. A clinical and pathological study. Ann Otol Rhinol Laryngol 89 (suppl 65): 3-23, 1980. 17) Monsell EM, Jackler RK, Motta G, et al.: Congenital malformations of the inner ear: histologic findings in five temporal bones, Laryngoscope 97 (supple 40): 18-24, 1987. 18) Phelps PD, King A, Michaels L: Cochlear dysplasia and meningitis. Am. J. Otol 15: 551-557, 1994. 19) Page EL, Eby TL: Meningitis after cochlear implantation in Mondini malformation, Otolaryngol Head Neck Surg 116: 104-106, 1997. 20) Govaerts PL, Casselman J, Daemers K, et al.: Cochlear implants in aplasia and hypoplasia of the cochleovestibular nerve, Otol Neurotol 24: 887-891, 2003.