Wow, this is amazing stuff. cochlear implants. I doubt my VA would cover this sort of thing however.
One of out students Francis, was born completely 100% deaf - just before she started school she was fitted with cochlear implants (she's now 11 or 12 years old). It took a good while for the tuning of the implants to be finalised, and she hated the effects of sound for a good while - and if the teacher was telling her off, she just used to turn the implants off!
Now you wouldn't know she has a problem, the implants have worked that well - but for martial arts purposes we need to be careful not to do anything which might cause damage to either her external hearing aids, or the internal implants.