Cerebrospinal Fluid Gusher in Cochlear Implantation

Kim, Chong Sun; Lim, Yune Sung; Chang, Sun O; Kwon, Bae Ju; Oh, Seung Ha; Kim, Young Ho; Lee, Hyo Jeong; Choi, Byung Yoon

Abstract

BACKGROUND AND OBJECTIVES
A cerebrospinal fluid (CSF) gusher during cochlear implantation can produce surgical difficulties and postoperative life threatening morbidities such as meningitis. Authors reviewed cases of CSF gushers during cochlear implantation, and assessed the radiologic characteristics of CSF gushers. SUBJECTS AND METHOD: From November 1988 to March 2004, 72 congenital deaf children with inner ear malformation underwent cochlear implantation in Seoul National University Hospital. Among these, 15 patients showed CSF gush intraoperatively. The medical records, the preoperative tem-poral bone HRCT and IAC MRI were reviewed retrospectively. RESULTS: Eighty percent (12/15) of CSF gushers had cochlear malformation. One case with a common cavity (100%), 6 of 15 cases of cochlear hypoplasia (32%) and 5 of 27 cases of incomplete partition (18.5%) showed CSF gush. The total or a partial defect of the modiolus significantly increased the risk of CSF gush. During the surgery, promontory mucosa around the cochleostomy opening was removed by electrocauterization and soft tissue pieces were packed in the posterior tympanum around the cochleostomy site after insertion of the active electrodes. Some additional procedures such as mastoid or middle ear obliteration were performed in two patients with intractable CSF gush. No lumbar drains were used. Postoperative meningitis developed in one case 7 months after cochlear implantation without a history of CSF leak. However, there were no evidences of CSF leak in all cases during the postoperative follow-up period (3-49 months, mean 24 months). CONCLUSION: Cochlear implant surgeons should be prepared to cope with CSF gusher during the cochlear implantation procedure in cases with congenital inner ear malformation, particularly if the patient has radiological evidence of modiolar defect.