Transmastoid implantability of an active transcutaneous bone conduction implant in adults with regard to the underlying pathology: a radiological simulation study

Abstract

Objectives: To compare the feasibility of transmastoid implantation of an active transcutaneous bone conduction device (BCD) in the most important pathologies of the temporal bone and the impact of implant lifts in adulthood.Methods: First, clinical predominant pathologies for implantation of this BCD were evaluated by a literature review. Then, high-resolution CT of 240 temporal bones with neuro-otologic diseases (NOD), chronic otitis media (COM), or cholesteatoma, respectively, were investigated regarding their implantability, using a radiological simulation program.Results: Chronic inflammatory diseases (CID) of the temporal bone with or without cholesteatoma account for most adults scheduled for an active BCD. Complete implantation was possible in almost all cases with NOD as well as COM, requiring an implant lift in 50% of COM and 20% of NOD (p = .025) cases. In contrast, in subjects with cholesteatoma, implantation required an additional tool in 92% of cases, leading to 59% implantability rate in these temporal bones.Conclusion: Adult subjects with CID of the temporal bone show more limiting anatomical conditions for transmastoid placement of an active transcutaneous BCD than those with single-sided deafness. Implant lifts increase the implantability significantly in subjects with COM and particularly in those with cholesteatoma.