Tinnitus
Signs and Symptoms

Tinnitus is one of the most elusive conditions that health care professionals face. It is an auditory perception not directly produced externally.

It is commonly described as a hissing, roaring, ringing or whooshing sound in one or both ears, called tinnitus aurium, or in the head, called tinnitus cranii.

The sound ranges from high to low pitch and can be a single tone, multi-tonal, or noise-like, having no tonal quality. Tinnitus may be constant, pulsing or intermittent. It may begin suddenly or progress gradually.

Tinnitus can be broadly classified into two categories: objective and subjective.

Objective Tinnitus

This form is audible to an observer either with a stethoscope or simply by listening in close proximity to the ear. Objective tinnitus accounts for less than 5 percent of overall tinnitus cases and is often associated with vascular or muscular disorders. The tinnitus is frequently described as pulsatile, or synchronous with the patient's heartbeat. In many instances, the cause of objective tinnitus can be determined and treatment, either medical or surgical, may be prescribed.

Subjective Tinnitus

This form is audible only to the patient and is much more common, accounting for 95 percent of tinnitus cases. Subjective tinnitus is a symptom that is associated with practically every known ear disorder and is reported to be present in over 80 percent of individuals with sensorineural hearing loss, which is caused by nerve and/or hair cell damage.

Because tinnitus, like pain, is subjective, two individuals may demonstrate identical tinnitus loudness and pitch matches yet be affected in significantly different ways. The severity of the tinnitus is largely a function of the individual's reaction to the condition. That said, many tinnitus sufferers:

• Have difficulty sleeping or concentrating
• Feel depressed or anxious
• Report additional problems at work or at home that may contribute to the distress caused by tinnitus
• Describe a correlation of tinnitus perception with stress
• It is often difficult to determine whether a patient's emotional state pre-existed, or is a result of the tinnitus.

Causes

Although the exact mechanism underlying tinnitus is unknown, it is likely that there are many related factors. Tinnitus usually, but not always, has to do with an abnormality of the hearing or neural system.

There are a number of causes linked with tinnitus including:

• Disorders in the outer ear, such as ear wax, a hair touching the eardrum, a foreign body or a perforated eardrum
• Disorders in the middle ear, such as negative pressure from eustachian tube dysfunction, fluid, infection, otosclerosis, allergies or benign tumors
• Disorders in the inner ear, such as sensorineural hearing loss due to noise exposure, aging, inner ear infection or Meniere's disease often accompanied by hearing loss and dizziness

Tinnitus also can temporarily result from certain medications, such as:

• Anti-inflammatories such as aspirin, ibuprofen, nonsteroidal anti-inflammatories and quinine
• Sedatives
• Antidepressants
• Certain antibiotics and chemotherapeutic agents

Other causes include:

• Systemic disorders such as high or low blood pressure, anemia, diabetes, thyroid dysfunction, glucose metabolism abnormalities, vascular disorders, growth on jugular vein, acoustic tumors and head or neck aneurysms
• Non-auditory disorders such as trauma to the head or neck, temporomandibular (jaw joint) disorders and neck misalignment

Current research suggests that even though tinnitus may initially be caused by an injury to the ear, ultimately an auditory pattern is established in the brain. Therefore, many treatment approaches are directed at the brain, not the ear.

Although the majority of tinnitus sufferers also have hearing loss, the presence of tinnitus does not indicate that one is losing hearing.

Reviewed by health care specialists at UCSF Medical Center.