Tinnitus is defined as any abnormal noise perceived by the patient when no external acoustic stimulus exists. In the United States, it is estimated that more than 35 million people are afflicted with tinnitus. Probably many more than this have experienced tinnitus transiently. Nearly 10 million people are estimated to have severe or troubling tinnitus symptoms. Tinnitus affects males and females in equal ratios, is most prevalent between ages 40 and 70, and occasionally affects children.<sup>15 Schleuning A.J. Tinnitus Head and Neck Surgery–Otolaryngology Philadelphia: JB Lippincott (1993). 

Cliquez ici pour aller à la section Références</sup> Tinnitus is generally divided into two categories: objective and subjective. Objective tinnitus refers to internal noise (or somatosounds), which may be audible to the physician. Typical causes of objective tinnitus include vascular abnormalities, neuromuscular disorders, and eustachian tube abnormalities. Objective tinnitus is less common than subjective tinnitus and may affect a younger cohort of patients. Subjective tinnitus refers to noise perception when there is no noise stimulation of the cochlea; subjective tinnitus is not audible to the physician but audible only to the patient. When all cases are considered together, subjective tinnitus is far more common.

Tinnitus has varied and multiple characteristics. It may be described as low pitched or high pitched, loud or soft, buzzing or ringing, paroxysmal or constant; occasionally, colorful descriptions of the noise are offered by the patient, such as crickets chirping or snakes hissing. Some patients also experience pulsatile tinnitus—sounds closely associated with the heart rate.

There are many possible causes of tinnitus, and a thorough history and physical examination should be directed at identifying the cause of the symptom. Often, no cause is determined, but other more serious disorders must first be ruled out before classifying tinnitus as idiopathic. Once a proper diagnosis has been established, treatment can be instituted.

The origin of tinnitus may be at any locus along the neural axis from the cochlear nucleus to the auditory cortex. The central pathways of hearing circuitry are quite complex. For this reason, tinnitus is a nonspecific symptom. The complex origins of tinnitus have frustrated physicians and patients with the available treatment options. As more research and knowledge accumulate on the subject, however, the options for management of tinnitus will improve. This article gives the primary care physician a basis of understanding of the various types of tinnitus, the diseases that are commonly associated with tinnitus, the current options available for treatment of the disease, and criteria for referral to an otolaryngologist and audiologist for evaluation of tinnitus and reviews recent research data on tinnitus.