What is necessary to evaluate a person with hearing loss?

The first step is a thorough history from the patient to search for possible causes of hearing loss such as infection, injury to the ear, occupational noise exposure, and degeneration due to aging and hereditary factors. Following this, a careful inspection of the eardrum and related structures is required. An audiogram (hearing test) is then performed which will determine the degree and type of the hearing loss and any difference between the two ears.
     
     There are two types of hearing loss. A sensorineural hearing loss is due to a problem in the inner ear (known as the cochlea) or in the nerve of hearing. A conductive hearing loss indicates a problem with either the ear canal, eardrum or the three small bones of hearing. This type of loss is often improved with surgery. Some patients may exhibit a mixed hearing loss, which is a combination of the two. The audiogram often determines whether any further studies are necessary to arrive at a diagnosis. Hearing loss due to aging or noise exposure has a fairly characteristic pattern on the audiogram, and usually does not require further testing. Other configurations on the hearing test may suggest the need for a radiological study of the ear or entire head (CT scan or MRI) or blood testing to rule out certain disorders which can cause hearing loss. It is especially important that a person with unilateral (one-sided) hearing loss be thoroughly evaluated to rule out any serious underlying condition (such as an acoustic neuroma).

Are noises (tinnitus) in the ear anything to be concerned about?

     Tinnitus may be perceived as whistling, ringing, running water or a myriad of other sounds. It may pulsate with the heartbeat or be nonpulsatile. Although no specific cause for the tinnitus may be found, it is important to rule out serious underlying conditions, which can cause this symptom. At a minimum, a complete history, physical exam of the ear and audiogram are required. Tinnitus is often associated with hearing loss. The evaluation of tinnitus is often similar to that for hearing loss.

     Pulsatile tinnitus (less common than nonpulsatile) usually requires a search for the possibility of abnormalities in the large blood vessels adjacent to the ear, or certain types of tumors that involve the ear (such as glomus tumors or arteriovenous malformations). If the tinnitus is due to hearing loss from aging (known as presbycusis), noise exposure or no specific cause is detected, patients may only be monitored with future audiograms. If the tinnitus is severe enough to cause interference with daily activities or sleep at night, symptomatic treatment with a hearing aid, biofeedback or various medications may be beneficial, but does not provide a "cure."

What is necessary to evaluate a person with dizziness or imbalance?

     Similar to the evaluation for hearing loss or tinnitus, this involves a complete history to determine the characteristics of the dizziness, whether it is constant or episodic, the duration and frequency of the spells and if there is any associated hearing loss or tinnitus. A general medical exam by your family physician to rule out heart disease, blood pressure fluctuations, diabetes, thyroid disorders or anxiety or emotional factors is a good starting point. However, it has been estimated that a significant percentage of patients who suffer from dizziness are afflicted with an inner ear disorder.

     The physical exam from the viewpoint of a neuro-otologist consists of careful inspection of the eardrum, general neurologic assessment as it pertains to balance and specialized office tests to search for unusual jerking eye movements (known as nystagmus) that indicate malfunction of the inner ear as it pertains to equilibrium. In addition, there are several laboratory diagnostic tests that are commonly performed:

1. Audiogram: the nerve of hearing (cochlear nerve) and the nerve of balance (vestibular nerve) are intimately related as they exit the brain and travel to the inner ear. Certain types of dizziness and imbalance are associated with specific patterns of hearing loss.

2. Electronystagmography (ENG): this is actually a battery of individual tests. Eye movements are recorded and analyzed by (in our office) an infrared scanner system. One portion of the test involves tracking a moving light target and provides information regarding control of eye movements. The next portion of the test records eye movements with the head in various positions to detect if the inner ear responds abnormally. The last portion of the study involves placing a current of warm and cool air or water in the ear canal to stimulate the inner ear balance system. This produces nystagmus, which can be recorded.

3. Computerized Dynamic Posturography (CDP): this study looks at the interaction of the visual (eye), vestibular (inner ear) and proprioceptive (muscle and joint sense) systems and how they function to maintain equilibrium. It involves standing on a movable platform and observing an artificial landscape that can be allowed to sway. By moving the platform and landscape individually or together, information is obtained about the function of the above-mentioned systems.

   
   
   

   Hearing Loss	Imbalance/Dizziness
   Tinnitus	Types of Dizziness

   What are some common types of inner ear causes of dizziness?   

   Benign Paroxysmal Positional Vertigo (BPPV): this disorder usually leads to brief, but often intense vertigo (spinning) following specific types of head movements. Hearing loss is usually not present. This disorder is due to dislocation of calcium carbonate crystals, which are present in the balance apparatus of the inner ear. It is managed with one of several types of physical therapy for the vestibular system. Rarely, surgery is required.   

   Meniere's Disease: this involves hearing loss (which often fluctuates and is usually in the low tones), a feeling of pressure or fullness in the ear, tinnitus and episodes of vertigo that last from 15 minutes to several hours. This disorder is due to excess fluid accumulation in the inner ear. Standard medical treatment consists of diuretics to reduce the excess fluid, medications to suppress the vestibular system during acute attacks of dizziness and avoidance of caffeine, salt, alcohol and nicotine. Severe cases often require further treatment, which may include injection of medication into the ear or one of several available surgical procedures to control the dizziness.   

   Viral Labyrinthitis: this often presents as sudden-onset dizziness which may be severe and last for several days to a week. Patients are often unable to work during this time. Following resolution of the severe symptoms (which often includes an element of vertigo), commonly a sense of imbalance or "drunkenness" persists for weeks or months which is generally worsened with head or body movement. Initial therapy may consist of various medications to control the vertigo, but long-term treatment to lessen the residual imbalance is usually in the form of vestibular physiotherapy exercises.

       Other causes of inner ear balance disorders include chronic infections of the ear, inflammatory or autoimmune diseases, trauma, tumors of the cochlear and vestibular nerves (specifically acoustic neuromas) and certain medications or industrial chemicals which damage the inner ear balance mechanism.