Often much of hearing loss is due to otosclerosis, a growth of material over and at the edges of the baseplate of the stapes. The stapes is the third of those three tiny bones in the ear, behind the eardrum (timpanic membrane), and it covers the opening to the inner ear where the tiny hair cells bathed in fluid pick up sound transmitted from the outside world. As that growth of material thickens over time, it takes louder sound to produce the same vibration intensity in the inner ear. Nerve damage also can desensitize hearing, and the effect is not the same for all sound frequencies.
Hearing aids boost the sound level so as to produce the proper intensity in the inner ear. Modern aid circuitry lets the degree of sound amplification vary with the nature of the sound (soft speech vs loud explosive sound) and with frequency. Optimum results from a hearing aid require careful adjustment of the amplification process.
But there is another option for improving hearing when the primary cause of loss is otosclerosis. There is the stapedectomy operation, which involves removal of the stapes, covering the opening to the inner ear with a disc of suitable material (eg. taken from part of the outer ear), and bridging the gap between that disc and the middle bone (incus) with an artificial stapes. The replacement typically is a tiny cylinder of platinum or plastic with a wire that is used for attachment to the incus.
A newer variation on stapedectomy, stapedotomy, involves leaving the stapes in place, creating a small hole in its base plate, and inserting a small cylinder there to conduct vibrations to the inner ear.
The only way to assess whether a surgical approach to hearing loss is appropriate is to have a thorough hearing test by a competent audiologist, as loss due to nerve damage won't be corrected by surgery. I have to wonder if having a hearing test performed by a company in the business of selling hearing aids gives a biased recommendation.
In my case, I had the stapedectomy operation done on one ear nearly four decades ago, as my loss was mostly due to otosclerosis. I preferred a good internal corrective solution to what would have been a perpetual nuisance with an external device. My father had one, even further back, and he hated it. But hearing aid technology back then was nowhere close to what it is today, I'm sure surgical solutions are more refined now, and I'm sure a decision made today would not be easy. In recent years, hearing in my ear with the artificial stapes has diminished notably, and I have to wonder if that is due to the same sclerosis process that led to surgery way back then. I'm not sure which route would be best for me at my age now.
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