EarDrops.com

There are multiple causes for hearing loss in adults, but these causes can be classified into two main categories; conductive causes and sensorineural causes.

Conductive hearing loss occurs due to the presence of a physical obstacle in the way of the motion of the sound waves through the affected ear, like in the ear canal blockage. Some examples of the conductive causes of hearing loss are:

- Clogging of the external auditory meatus, due to building up of the ear wax (cerumen), accumulation of blood (hematoma), or the presence of some foreign objects.

- Perforation of the eardrum, due to trauma caused directly by pushing a cotton pellet or a finger in the middle ear, otitis media, or blast injuries

- Ossicle dislocation due to severe trauma to the ear

- Infection of the middle ear (otitis media)

- Swelling of the external part of the ear canal due to infection (otitis externa)

Sensorineural hearing loss is this type of deafness that occurs due to the destruction of the hair cells or the nerve endings of the auditory nerve, which are responsible for feeling the waves of the sound. The Sensorineural causes for hearing loss
include:

- Acoustic trauma, due to the exposure to very loud noises for a long period of time, usually such loud voices reduce the sensitivity of the cochlea in the inner ear.

-Ear squeeze or barotrauma, as in divers

- Severe head injury that causes the fracture of the temporal bone in the skull

-Some medications, called ototoxic drugs, can harm the auditory or hearing nerve when taken in small doses for a long
time, like :

• Certain types of antibiotics, especially erythromycins and aminoglycosides
• Diuretic drugs
• Aspirin and NSAIDs (non-steroidal anti-inflammatory drugs) e.g. naproxen and ibuprofen
• Anti-neoplastic medications (drugs for treating cancer)

- Diseases of the blood vessels, like polycythemia, sickle cell anemia, and leukemia

- Renal problems

- Meniere syndrome, this is a disease affecting the inner ear causing hearing impairment and loss of balance, it is usually accompanied with vertigo and tinnitus

- Tumors in the hearing nerve, or Acoustic neuroma

- Different types of infections, like mumps, influenza, measles, herpes simplex, herpes zoster, syphilis, and meningitis.

Finally, one of the most common causes for hearing loss is aging, this type of hearing loss is known as presbycusis

The road map for the building of the proteins in the body is the genes. It is worth mentioning that the proteins are the basic units of all the body’s organs, including the eyes, the ears, the heart, the hair, the lungs…etc. Every one of us inherits half of his or her genes from one parent and the other half from the second parent. If the genes inherited from one or both parents are defective, then the congenital anomalies will show.

Deafness or hearing loss is a very common congenital disease; nearly three out of every thousand babies are born with this birth defect. Actually, the inherited genes are responsible for about sixty percent of the hearing loss in babies. Furthermore, some recent studies are suggesting that the partial and the complete loss of hearing ability in the senior people are also due to the genetic factors.

The hereditary hearing loss can be classified into the following two main categories: non-syndromic and syndromic. The non syndromic deafness accounts for approximately seventy percent of all cases of the hereditary hearing loss. Non-syndromic hearing loss is the type of inherited deafness which isn’t accompanied with other symptoms, while syndromic hearing loss is associated with some anomalies in different parts of the body. Various types of the non-syndromic hearing loss are usually termed according to their mode of inheritance. Mostly, non-syndromic hearing loss is due to the damage of one of the parts of the inner ear. The inner ear is normally formed of three main structures; the cochlea that aids in the processing of the sounds, the nerves to transmit the received information to the brain, and finally the structures responsible for the balance. Sensorineural hearing loss is the type of the deafness, which is
caused by the inherited alterations in the structures of the inner ear.

The conductive deafness is the loss of hearing due to the changes in the structures of the middle ear. The middle ear consists of three small bones, which transmit the sounds from the eardrum to the inner ear. Some types of the non-syndromic hearing loss, especially a form known as DFN3, are caused due to some changes in both; the middle ear and the inner ear, and this type is known as mixed deafness.

The Inherited hearing impairment can be unilateral (affects one ear) or bilateral (affects both ears). Besides, the severity of the hearing loss can vary from the difficulty to understand low speech (mild type) to the failure of hearing the very high sounds (profound type).