Tinnitus is a condition characterized by the perception of noise or ringing in the ears when no external sound is present. This sound may be heard as a humming, buzzing, whistling or hissing. It may be periodical or persistent, low-pitched or high-pitched. Tinnitus is a sign of an underlying condition that needs attention and not a disease in itself. While the condition looks like it is associated with the ear its real reason is in the brain cells.
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