Comparison of artefact reduction possibilities with the new active transcutaneous bone conduction implant (Bonebridge).

OBJECTIVE: This study aimed to evaluate the possibilities of artefact reduction using different anatomical implant positions with the Bonebridge bone-conduction hearing implant 602 for a patient with an acoustic neuroma requiring regular diagnostic magnetic resonance imaging of the tumour position. METHOD: Three implant positions and magnetic resonance imaging examinations with and without customised sequences for metal artefact suppression were investigated. The diagnostic usefulness was rated by a radiologist (qualitative evaluation), and the relation between the area of artefact and the total head area was calculated (quantitative evaluation). RESULTS: Following the qualitative analysis, the radiologist rated the superior to middle fossa implant placement significantly better for diagnostic purposes, which is in agreement with the calculated artefact ratio (p < 0.0001). The customised slice-encoding metal artifact correction view-angle tilting metal artifact reduction technique sequences significantly decreased the relative artefact area between 5.13 per cent and 25.02 per cent. The smallest mean artefact diameter was found for the superior to middle fossa position with 6.80 ± 1.30 cm (range: 5.42-9.74 cm; reduction of 18.65 per cent). CONCLUSION: The application of artefact reduction sequencing and special anatomical implant positioning allows regular magnetic resonance imaging in patients with the bone-conduction hearing implant 602 without sacrificing diagnostic imaging quality for tumour diagnosis.

Postoperative changes in telemetry measurements after cochlear implantation and its impact on early activation.

INTRODUCTION: Cochlear implantation is a clinically routine treatment for patients with severe sensorineural hearing loss for over 20 years. Up to now, the general recommendation for speech processor activation was 4 weeks after cochlear implantation. The aim of this study was to determine whether activation is possible at <4 weeks postop and to show the postoperative change in telemetry over time. MATERIAL AND METHODS: The study was retrospectively carried out at the Karl Landsteiner University Hospital St. Pölten, Austria. Patients who routinely received a CI between January and August 2013 were included in this study. Two weeks after the surgery clinical complications, the ability to wear the audio processor and the impedance values were analysed. RESULTS: Forty-five patients were included in this study. Forty patients were examined at the first postoperative visit, scheduled 2 weeks after the surgery. In nine cases, a mild wound-healing complication occurred; just in one patient, the activation could not carry out immediately. There were no statistically significant differences between the intraoperative, the 2- and 6-week postop impedance measurements for each channel. DISCUSSION: We used the minimally invasive approach and soft implantation technique in all of our patients and believe this to have been a major reason that earlier activation was possible. With this technique, you can reduce the wound-healing process, which makes it possible for the wound to heal fully and for the patient to wear the sound processor over the wound without problems. We found out that telemetry is not a predictor for the time of activation. CONCLUSION: Based on the results in this study, an earlier activation can be recommended. This will shorten the time the patient needs to wait following cochlear implantation, and rehabilitation can begin sooner.