Tinnitus is the medical term for "ringing in the ears" although some people hear other sounds. It is the subjective complaint of hearing a noise in the absence of any external sound. This noise may be heard in one ear, both ears, the middle of the head – or it may be difficult to pinpoint its location. The noise may be low, medium or high-pitched; there may be a single noise or two or more components to the sound; the noise may be continuous or it may come and go. Experiences of tinnitus are very common in all age groups, especially following exposure to loud noise, but it is unusual for it to become a major problem unless the exposure becomes chronic.
An important distinction must be made between a simple case of tinnitus
and Meniere's disease
, a more serious condition characterized by tinnitus, vertigo
, and hearing loss.
Incidence; Causes and Development
Approximately 10 to 20% of Americans suffer from mild tinnitus
and 80% of those hear ringing constantly. Of the elderly, 30% experience tinnitus.
Besides loud noises, other causes include severe head trauma, sinus
and respiratory infections, ear infections, wax build-up, high blood cholesterol
problems, food allergies, certain types of tumors
and a long list of other conditions. In one database of 1,687 tinnitus
patients, noise exposure was the cause of 24% of cases and no known cause was identifiable in 43%.Pulsatile Tinnitus
Sometimes a tinnitus noise beats in time with your pulse. This is called pulsatile or vascular
tinnitus. Approximately 3% of tinnitus patients experience this kind of tinnitus; people with pulsatile tinnitus typically hear a rhythmic pulsing, often in time with a heartbeat. The most common cause of pulsatile tinnitus is arterial
turbulence, a noisy blood flow caused by plaques or kinks in the arteries
in the head or neck. It can be made worse if there is also hypertension
. Many forms of pulsatile tinnitus are treatable.
Here is a list of the possible causes of pulsatile tinnitus:
- Arteriovenous malformations (AVMs.) AVMs are abnormal collections of arteries and veins that sometimes occur within the cranial cavity near the auditory nerve. AVM pulsation against the auditory nerve stimulates the nerve, resulting in a pulsating tinnitus.
- Carotid artery-cavernous sinus fistula. This is an abnormal connection between a very large artery and a very large venous pool within the cranial cavity. It is usually the result of severe head trauma. Treatment is nonsurgical, requiring the services of a radiologist.
- Chronic inflammation and/or infection of the middle ear. Chronic inflammation is almost always accompanied by increased blood flow to the inflamed tissue; since this tissue is in the ear, some people are able to hear the increase in blood flow.
- Middle ear fluid. The middle ear is normally an air-filled space. If, due to infection, inflammation or eustachian tube dysfunction, fluid accumulates behind the middle ear then pulsating tinnitus may result.
- Vascular tumors in the middle ear. These are most commonly referred to as glomus tumors or paragangliomas. They are benign but can be troublesome and surgery is required for correction of this problem.
- Venous hum. Patients who are pregnant, anemic, or have thyroid problems may develop increased blood flow through the largest vein in the neck, the jugular vein. The jugular vein carries blood from the brain back to the heart; in so doing, it traverses the middle ear. Turbulent blood flow anywhere in the course of the jugular vein can be heard in the middle ear as a "hum" which may or may not fluctuate with the pulse. Correction or resolution of the underlying problem often results in improvement.
Many patients recover spontaneously – with or without treatment – during the first 6 months of suffering. Chronic tinnitus
results when the disturbing symptom is present for more than 6 months.