Tinnitus is a ringing, swishing, or other type of noise that seems to originate in the ear or head. In many cases it is not a serious problem, but rather a nuisance that eventually resolves.
It is not a single disease, but a symptom of an underlying condition. Nearly 36 million Americans suffer from this disorder. In almost all cases, only the patient can hear the noise.
What causes tinnitus ?
Tinnitus can arise in any of the four sections of the ear: the outer ear, the middle ear, the inner ear, and the brain. Some tinnitus or head noise is normal. If one goes into a sound proof booth and normal outside noise is diminished, one becomes aware of these normal sounds. We are usually not aware of these normal body sounds, because outside noise masks them. Anything, such as wax or a foreign body in the external ear, that blocks these background sounds will cause us to be more aware of our own head sounds. Fluid, infection, or disease of the middle ear bones or ear drum (tympanic membrane) can also cause tinnitus.
One of the most common causes of tinnitus is damage to the microscopic endings of the hearing nerve in the inner ear. Advancing age is generally accompanied by a certain amount of hearing nerve impairment, and consequently tinnitus. Today, loud noise exposure is a very common cause of tinnitus, and it often damages hearing as well. Unfortunately, many people are unconcerned about the harmful effects of excessively loud noise, firearms, and high intensity music. Some medications (for example, aspirin) and other diseases of the inner ear (Meniere's syndrome) can cause tinnitus. Tinnitus can in very rare situations be a symptom of such serious problems as an aneurysm or a brain tumor (acoustic tumor).
The above information thankfully comes from the medicinenet.com at the following link.