20 M with hearing loss, fullness and tinnitus in the right ear for about a year; may have begun with an ear infection. Had hearing problem etc for two weeks in the same ear due to probably a blast injury, about 5 yr back, and was asymptomatic until one year back. (I got it right?)
Hope you are otherwise healthy.
The middle ear is a an 'air-bubble' cavity deep to the ear drum. It has a ventilation tube (eustachian tube) opening into the backyard of the nose (nasopharynx), through which the middle ear pressure is maintained equal to the atmospheric pressure.
There are some situations in which this tube may get blocked or swollen and thus affect the middle ear pressure etc, and reduce the hearing.
Cochlea is part of the inner ear (the other part being 'vestibular organ' dealing with 'balance'), and sits in the skull bone deep to the middle ear, connected with the latter through two 'windows'. A loud blast can shake up the drum and middle ear so much that the whole shock is carried to the inner ear, rattling and maybe permanently damaging the fragile micro structures within it. Depending on the intensity of the 'blast' the magnitude of injury can vary. Some get full recovery, others partial.
You would have recovered to a good extent, and hence were not aware of any hearing impairment. (An audiogram done then would have thrown light into this) An infection in the same ear a year back, either put in some more damage or drew your attention to it.
Nasal endoscopy would have been done to ***** the dynamics of Eustachian tube. Since the ear may 'look' normal otherwise, tests are done to evaluate the hearing loss. A pure tone audiogram (you say that there was a dip in some high tone) will show if there is an inner ear problem or a middle ear problem or both. Sometimes an 'impedance audiometry' also is done.
It is difficult to say if it is a permanent cochlear damage without seeing the results ot the various tests. A feeling of unequal pressure in the head? You mean the right and left ears? If one middle ear is not aerated properly, this can happen.
You have to be under care of an ENT specialist to diagnose what is wrong, and to manage the problem, if any.
Hope this helps.
Rgds,
Thomas Antony
-- I should have mentioned that I am a 20 year old male