Introduction
Congenital aural atresia is the failure to develop the external auditory canal (EAC) and is often associated with microtia and compromise of the middle and internal ear. It affects 1 in every 10.000 to 20.000 births. Conductive hearing loss is the most common audiological finding.
Treatment options include a functional and an aesthetic approach. Bonebridge (Med-El, Innsbruck, Austria) is an active bone conduction implant that can be placed in the sinodural angle or in the retro sigmoidal position. Another option is middle fossa.
Objective
Since a retro auricular incision limits the aesthetic pinna reconstruction, and most of this children have an anatomy that make the selection of the position of the devise a challenge, the aim of this study is to present the middle fossa placement technique as a surgical alternative in children with microtia and EAC atresia who cannot undergo traditional surgery for active transcutaneous bone conduction implants (ATBCI) due to their altered anatomy and/or desire for future aesthetic reconstruction.
Materials and methods
A case series descriptive study was designed. The middle fossa technique was developed. Pre-operative and post-operative information from 72 patients with external auditory canal atresia (EACA) and implanted with ATBCI was reviewed.
Results
A total of 72 children with bilateral EAC atresia received implants in the middle cranial fossa. Their average age was 12. The follow up range is 8 years to 6 months. Of these patients, 14 had an associated congenital disorder: Goldenhar Syndrome, Treacher Collins Syndrome, or the Pierre Robin Sequence. The average follow-up was at 76 months (ranging from between 6 to 96 months). Seven patients showed skin erythema at the processor site after turn-on, which was solved by lowering the magnet strength, and one patient had a scalp hematoma that required puncture drainage.
The hearing thresholds went down on average from 66.5 dB to 27.2 dB one month after turn-on. Speech recognition improved respectively from 29.4% without and 88.9% with a bone conduction hearing aid to 96.4%.
Conclusions
Middle fossa technique for the active transcutaneous bone conduction implant in children was proven to be safe and effective for treating pediatric patients with external auditory canal atresia who cannot receive implants at the sinodural angle or in the retrosigmoidal position because of their altered anatomy and/or desire for future aesthetic reconstruction.

Active transcutaneous bone conduction implant placement in children: surgical options and how to adapt them to your patients.

It is with great pleasure and enthusiasm, that on behalf of the Cochlear Implant centers of the Radboud UMC in Nijmegen and Erasmus MC Sophia Children’s Hospital in Rotterdam to invite you to attend the 16th European Symposium on Pediatric Cochlear Implantation to Rotterdam, the Netherlands in 2023.

Yours sincerely, on behalf of the CI Centers at Radboud UMC and Erasmus MC,