Several weeks later, although hearing sensitivity had recovered to normal levels, activity in the auditory nerve connecting the inner ear to the brain remained impaired.
The number of channel molecules present means that, in normal circumstances, about 70% of the free-floating outer channels are lined up with tethered inner ones at any given time, with each dual channel letting through about 1m sodium ions per second.
"If there is only a problem in its inner layer, it may be possible to replace just that part of the cornea, leaving the patient's normal and healthy tissue in place, " said Mr Muhtaseb, a Singleton-based consultant ophthalmologist.