Introduction:
During 2006 – 2008, five deaf patients were implanted at Hannover Medical School (MHH)
with a novel hearing prosthesis within the inferior colliculus (IC), known as the
single-shank auditory midbrain implant (AMI). It has a straight array of 22 sites
(by Cochlear Limited) and was developed as an alternative to the auditory brainstem
implant (ABI) for people especially with Neurofibromatosis 2 (NF2) who have no intact
hearing nerve and where a cochlear implant is ineffective. However, hearing performance
for the five AMI patients consisted mainly of improvements in lip-reading similar
to that of ABI patients with NF2.
Methods:
Further animal and human studies showed that the limited hearing performance was likely
related to suppressive effects in the IC induced by temporal stimulation patterns
when presented on a single-shank array. Therefore, a new AMI having two shanks in
parallel was developed (11 sites along each shank) and is going to be implanted in
five patients in a second clinical trial at MHH funded by National Institutes of Health
(U01DC013030). Different clinical tests will be performed for example pitch ranking
or scaling, with the goal to develop a better stimulation strategy that improves speech
performance.
Results:
In 2017 the first patient was implanted without complications, the implant is running
well, and we got initial data so far.
Conclusions:
It could be shown a safe implantation of a two-shank AMI and that we could collect
first data. Nevertheless, further testing is needed to collect more data though.