The Ear and how it might not work
The easiest way of understanding an ear or auditory system is to break it down to its component parts and consider what might not be functioning as it should with each of them. So we refer to the anatomy again and look at the outer ear and ear canal, the middle ear and the inner ear.
A normally functioning ear canal catches sound waves and funnels them to the tympanic membrane which responds by vibrating. Any interruption of this process prevents the soundwave from being conducted along the ear canal and is known a a conductive hearing loss. Some examples of possible causes are:
Treatment is usually successful in correcting such loss, blockage can be removed by an earcare professional and in fact we routinely perform microsuction ear cleaning in our earcare clinic. Infection can be treated by your doctor and physical damage may be repaired surgically.
In a normally functioning middle ear the vibrations of the tympanic membrane are conducted through the middle ear space by the tiny middle ear bones known as the ossicles or ossicular chain. For this to happen the air pressure in the middle ear space must be equal to that in the ear canal. This is maintained by the regular ventilation provided by a tube known as the eustachian tube which brings air from the throat to the middle ear. Quite a lot can happen to disturb this process and here are a few examples:
On occasion fluid in the middle ear may resolve itself. But in general it is safe to say that conductive hearing loss will almost always require treatment from a healthcare professional. This may vary in complexity from the simple removal of an obstruction through the administration of medication to surgery for otosclerosis or cholesteotoma. Because of it's nature, conductive hearing loss may be of sudden onset and it may be one-sided. So if you notice any such symptoms you should consult your GP or a hearing care professional.
A conductive hearing loss will show up during a standard pure tone hearing test and an example of the resulting audiogram can be seen by cllcking the link below:
In normal function the pumping action of the stirrup is picked up by the membrane at the oval window. This makes waves in the fluids of the inner ear sac. These waves cause a kind of rocking motion in a membrane within the inner ear (think a plank bobbing on a gentle ocean wave). Attached to this membrane are hair cells which become electrically excited by the movement. This excitement becomes nerve impulse which is sent to the acoustic nerve and then to the brain.
These hair cells can be damaged so that not as much nerve impusle is sent to the brain. This is known as sensori or nerve deafness. It's commonest cause is the ageing process and this can be hastened by excessive exposure to noise. Examples of other possible causes of sensori loss are:
In it's benign form as a result simply of the aging process, the hearing loss should be of gradual onset and should occur more or less equally on both sides. Untreated sensori loss which is onesided and/or of sudden onset should always be a matter for a primary health care professional to refer for detailed investigation.
Age related sensori hearing loss is the most common of all measurable hearing loss. It can be very effectively treated by the fitting of modern and discreet digital hearing aids.
A sensori hearing loss will show up during a standard pure tone test and an example of the resulting audiogram can be seen by clicking the link below:
If you have any questions, or you would like to find out about your hearing, please call us on 0141 954 6030 for a chat or we can book an appointment for you