New cochlear implant technologies improve performance in post-meningitic deaf patients.

The objective of the study was to compare the performance of cochlear implantation between post-meningitic and non-meningitic patients, and to evaluate the impact on hearing outcome of technical advances in cochlear implant technology. Retrospective chart review was used as the study design. Twenty adults with post-meningitic profound hearing loss receiving unilateral or bilateral cochlear implants between 1990 and 2008 were tested. Results were compared to a control group of 46 adults implanted for a non-meningitic hearing loss, with the same pre-operative speech scores. Speech scores were poorer in post-meningitic patients compared to those of control group, whatever the duration after implantation (p < 0.0001). Speech scores of subjects implanted and fitted before 2001 were compared to those of subjects implanted after 2001, with the same duration of hearing loss. Performance improved with implants and processors available after 2001, with a magnitude of improvement higher in post-meningitic patients (p < 0.0001 and p < 0.05 in post-meningitic and control groups, respectively, two-way ANOVA). Consequently, speech scores of post-meningitic patients implanted after 2001 achieved those of control subjects (two-way ANOVA). Advances in cochlear implant technology and coding strategy improve hearing outcome in post-meningitic adult patients, who now achieve similar performance as those of non-meningitic patients.

Intraoperative electromyography and surgical observations as predictive factors of facial nerve outcome in vestibular schwannoma surgery.

OBJECTIVE: To evaluate the predictive value of electromyographic recordings for the immediate facial nerve outcome after solitary vestibular schwannoma (VS) removal. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary referral center. PATIENTS AND METHODS: From November 2005 to July 2007, 120 operated solitary VSs monitored by NIM Response 2.0 (Medtronic, Xomed, Jacksonville, FL, USA) were included. Intraoperative direct facial nerve stimulation at the brainstem (proximal pre site) before resection and at the brainstem (proximal post and distal sites, respectively) and internal acoustic meatus after resection were performed. Intraoperative recordings were performed on 4 muscles: Frontalis, Orbicularis oculi, Orbicularis oris, and chin muscles (CM). Postoperative facial function (House-Brackmann classification) was evaluated at postoperative Days (D) 2, 8, and 30. Grades 1 or 2 were considered as a good result. RESULTS: A good postoperative facial function was obtained in 71, 63, and 77% at postoperative D2, D8, and D30, respectively. Maximal conduction block was found at Day 8. Poor facial nerve outcomes were observed for large tumor with a facial nerve superior to the tumor with a strong adhesion to the nerve. With a stimulation threshold at proximal site after proximal site tumor resection at less than or equal to 0.04 mA, a good facial function was observed in 77% at Day 8. Using these criteria together with CM responses greater than 800 muV to supramaximal stimulation at (proximal post site) and a proximal/distal post ratio at CM response greater than 0.6, 93% of patients presented with a good facial function at Day 8. CONCLUSION: Using CM recording stimulation and supramaximal stimulation of the facial nerve in combination with thresholds seem to increase the predictive value of the monitoring for the immediate facial nerve function for VS surgery.