Tinnitus is often described as a “ringing in the ears,” but it can also be a buzzing, roaring, clicking or hissing. It's not a disease –  it's a common symptom of other ailments, one that affects about 1 in 10 Americans.

A study shows that among an estimated 222.1 million U.S. adults, 21.4 million (9.6 percent) experienced tinnitus in the past 12 months. Among those who reported tinnitus, 27 percent had symptoms for longer than 15 years, and 36 percent had nearly constant symptoms. Higher rates of tinnitus were reported in those with consistent exposure to loud noises at work and during recreational time. Years of work-related noise exposure correlated with increasing prevalence of tinnitus.

In terms of subjective severity, 7.2 percent reported their tinnitus as a big or a very big problem compared with 42 percent who reported it as a small problem. Only 49 percent had discussed their tinnitus with a physician.

Tinnitus may be an indicator of a head or ear injury, exposure to loud noise, a circulatory disorder (including high blood pressure), or age-related atherosclerosis-sourced hearing loss. Rarer and more serious conditions that can cause tinnitus include:

• Meniere's disease, an inner ear disorder;
• Any kind of tumor that may form in your head or neck, including acoustic neuroma, a benign tumor that forms on the cranial nerve that runs from your brain to your inner ear and controls balance and hearing; and
• Problems with the temporomandibular joint, that joint on each side of your head in front of your ears

In many cases, the exact cause of tinnitus is never discovered.

The most common type of tinnitus is “subjective,” meaning that only you can hear the noise. Much more rare is “objective” tinnitus which your doctor can hear when she does an examination. This may be causedby a middle ear bone condition, a blood vessel problem or muscle contractions.

In order to relieve the symptom of tinnitus, your doctor will need to diagnose the underlying condition that causes it. An audiological exam, which will rule out certain age-related causes, is usually the first step. Computer tomography and/or magnetic resonance imaging will likely follow.

The actual sounds you hear – ringing, buzzing, clicking, etc. – will also provide your doctor with clues regarding their source. For example, a low-pitched ringing in one ear is strong indicator of Meniere's disease, while clicking sounds are symptomatic of some muscular condition.