– The perception of sound in the absence of an acoustic stimulus, which may be intermittent, continuous, or pulsatile.
Causes and Incidence
The etiology is unknown, but tinnitus occurs as a symptom in nearly every disorder of the ear. Contributory factors include obstruction of the external ear canal; infection and inflammation; use of certain drugs (sali-cylates, quinine, aminoglycoside antibiotics, thiazide diuretics); exposure to certain toxins (carbon monoxide, heavy metals, alcohol); damage to cranial nerve VIII; underlying cardiovascular disease, anemia, or hypothyroidism; and acoustic or head trauma. An estimated 30 million individuals in the United States are thought to suffer from tinnitus.
The pathophysiologic mechanisms of tinnitus remain obscure.
The primary manifestation is a sound variously described as ringing, roaring, sizzling, whistling, humming, buzzing, hissing, or clicking. It may be intermittent, continuous, or pulsatile and may be accompanied by a hearing loss.
Tinnitus that is loud, high pitched, and continuous has been known to drive some individuals to attempt suicide if treatment fails.
An audiologic examination is done to rule out underlying systemic disease or disease of the ear known to produce tinnitus. The examination will also reveal any hearing loss. Measurements of tone masking also are done. Pulsatile tinnitus calls for a workup of the vascular system for aneurysm, obstruction, and neoplasm.
Antianxiety agents and anticonvulsants (e.g., Tegretol) combined with Mysoline or Dilantin at night for sedative effect.
Correction of any associated hearing loss; treatment of underlying disease; use of background noise to mask tinnitus; use of a tinnitus masker worn in the ear to produce a more pleasant sound; avoidance of causative drugs or toxins.