PTFE Sheets for fixation of auditory brainstem implant (ABI) stimulating probes in children may improve hearing outcomes.

OBJECTIVE

Fixation of the stimulating probe of auditory brainstem implants (ABI) is crucial to maintain beneficial stimulation. Use of Tetrafluorethylen (PTFE, TeflonTM) sheets as a fixation material was compared to fixation without PTFE-sheets.

SETTING

Tertiary referral center.

STUDY

DESIGN

Retrospective analysis.

PATIENTS: 46 children with sensorineural hearing loss, not eligible for CI, received an ABI; 27 children without PTFE (Control Group, CG), 18 children with PTFE (TeflonTM Group, TG). Mean age of CG (46.6 months), TG (37.4 months), n.s. Mean follow-up 49.3 months (CG), 33 months (TG), n.s.

MAIN OUTCOME MEASURES: Number of stimulating probe dislocations, number of active electrodes, electrically evoked auditory-brainstem-response (eABR) morphology performed intraoperatively and postoperatively, maximum comfortable level (MCL), categories of auditory-performance (CAP) scores.

RESULTS

TG showed no electrode dislocations, CG had one. eABR waves varied from 2 to 5 in both groups, number of active electrodes was similar. Mean MCL was sign. lower in TG (49.2 nC) vs CG (98.6 nC). CAP scores were sign. better in TG (5.0) vs CG (4.2), after 2 years and 5.4 vs 4.6 after 3 years post-activation.

CONCLUSION

PTFE sheets proved to be an effective and stable fixation material for ABI stimulating probes, resulting in potentially better auditory outcomes as indicated by significantly lower MCLs and improved CAP scores. Compared to other fixation materials used in the CG, PTFE-sheets appear to be the better choice.