Initial investigation of the efficacy and biosafety of sodium hyaluronate (Healon) as an aid to electrode array insertion.

Sodium hyaluronate has potential uses as an electrode lubricant in cochlear implant surgery. Deeper electrode insertions were achieved in six temporal bones implanted with sodium hyaluronate, compared to 22 patients implanted without sodium hyaluronate. Preliminary biosafety studies measuring hearing thresholds of six cats 4 months after implantation with dummy electrodes did not show evidence of ototoxicity caused by sodium hyaluronate. Until the biosafety studies are complete, we cannot recommend sodium hyaluronate for routine use, but the results so far are promising.