Cochlear implants are an option for those with severe to profound sensorineural hearing loss in which hearing aids are providing little or no benefit. A cochlear implant consists of two parts. The first part is an internal component that is surgically implanted into the cochlea and skull.
The second part is the external device that acts as a microphone and processor that transfers the sound through the skin into the internal device by way of an electromagnet that sits on the skin over the internal device. The reader is referred to the websites of the manufacturers (Advanced Bionics Corporation, Cochlear Americas, and MedEl Corporation) for a detailed discussion of the surgical procedure, and pictures of the device, as well as a more detailed discussion of this topic. The following discussion is a simple summary.
Age 12 months or older, Severe to profound sensorineural hearing loss, Little or no benefit from appropriate hearing aids, Presence of a cochlear nerve and cochlea (may be incompletely formed). No contraindications to general anesthesia. A medical work up by the implant team usually includes special hearing testing, a CT scan and MRI scan of the head, and speech therapy evaluation. Most insurance companies require meeting Food and Drug Administration requirements based on this workup before they will approve proceeding with surgery.
Emotional Issues Related to Hearing Loss
The recognition of a hearing loss or a hearing disorder is frequently an emotional one for the individual and his or her family.
How Do I Know if I Have a Hearing Loss?
As individuals age, they may suspect they have a hearing loss but just aren't sure. Or, their children or grandchildren may believe their aging relatives may be experiencing a hearing loss.
This document serves as a good starting point for self-assessment.
Leading Causes of Hearing Loss
There are a number of factors that may cause or contribute to hearing loss. Some of them are hereditary. Others are caused by illnesses or trauma. Still, others are “environmental” in nature.
Some Symptoms of Hearing Loss
How can you tell when someone you know is experiencing a hearing loss? Frequently, individuals display one or more behaviors that may indicate they are having trouble hearing.
Tinnitus ("Ringing" in the Ears")
Many persons live with the sensation of having “ringing in their ears” or perceive some other intrusive sounds. This is known as “Tinnitus.”
Who's Who in the Evaluation and Treatment of Hearing-Related Problems
There are a number of qualified professions that specialize in the diagnosis, treatment and management of hearing-related and balance-related problems and diseases. Some are physicians with training in otolaryngology and otology. Others are non-physicians with master's degrees in audiology.
Helpful Links For Those With Hearing Loss
Persons who are deaf or who have a hearing loss will find a variety of resources available to assist in the amplification of sound and/or to replace their dependency on sound. Audiologists are excellent resource professionals and are knowledgeable about the plethora of available resources.
Some resources include hearing aids, telephones with flashing lights to signal incoming calls, doorbells with a light source, and special amplification devices.
The term “dizziness” applies to a multitude of conditions that is best evaluated through a systematic approach. Diagnosing the cause of the dizziness is the key to treating most cases of dizziness. Identifying and treating the cause of the dizziness usually results is the cessation of symptoms, instead of relying on drugs to control the dizziness. A thorough history and physical examination by your physician is often the most important diagnostic tool in diagnosing the cause of dizziness. Often, this requires a physician who specializes in the evaluation and management of dizziness. Typically, Neuro-otologists (sub-specialists within Otolaryngology) or Neurologists provide this expertise.
A detailed history of the dizziness is the single most important information in making a diagnosis. A history of imbalance must be distinguished from true vertigo (the sensation of spinning or movement). The onset and duration of the dizziness, whether the symptoms are provokeable or spontaneous, whether hearing loss or tinnitus is involved, and whether other symptoms accompany the dizziness, are all critically important in the diagnosis.
A physical examination is important to evaluate the ears and neurological system. Tests to provoke dizziness, such as changing pressure in the ear canal (fistula test) and special positioning tests (Dix-Hallpike maneuvers), are often done at this time.
Based on the history and physical examination, various tests can be obtained to help establish the diagnosis. A hearing test and MRI scan of the head are often ordered. Tests specifically to evaluate the balance system include an electronystagmogram (ENG), rotary chair test, and dynamic posturography. All of these tests are non-invasive, are done in an office setting, and evaluate different parts of the balance system, looking for lack or abnormal balance function in the brain and spinal cord, inner ear and visual systems.
Based on the history, physical examination, and appropriate testing, the cause of the dizziness can usually be identified and treated. The following is a list of some of the more common types of dizziness:
Benign Paroxysmal Positional Vertigo
Characterized by spells of vertigo provoked by laying the head down, or forward, lasting seconds to minutes. This is the most common cause of vertigo. It is due to a free-floating calcium particle in the semicircular canals of the inner ear. Treated very effectively by a positioning maneuver in which the patient is rolled on a bed in a defined fashion that effectively clears the semicircular canal of the particulate matter, resulting in a dramatic resolution of symptoms.
Viral, drug-induced or vascular injury to the inner ear. Severe spells characterized by 3-7 days of vertigo, nausea, and vomiting, followed by 1-3 months of imbalance that gradually dissipates. Must be distinguished from stroke and tumors. Treated symptomatically until it resolves. Imbalance may require special physical therapy to hasten balance recovery. Milder attacks are harder to diagnose with less severe symptoms. Generally, does result in recurring bouts of dizziness.
Results in spontaneous bouts of vertigo lasting seconds to minutes, usually in the absence of headache. Is a hereditable cause of dizziness. The evaluation, including physical examination, hearing tests, and balance tests, are usually normal. Treated primarily with drugs that prevent vascular arterial spasm that is believed to be the cause of most migraine-induced symptoms.
Leakage of inner ear fluid (perilymph) can result from trauma or pressure changes to the ear. Car accidents, scuba diving and airplane depressurization are well-known causes. Sometimes this occurs without known cause. Patients will get dizzy with any straining, nose-blowing, or pressure changes in the ear. Can also result in sudden hearing loss (sensori-neural type). Diagnosis in made by inducing dizziness by altering pressure in the ear canal (fistula test). Treatment includes bed rest and/or surgical exploration of the middle ear through the ear canal.
Acoustic Neuromas and Other Tumors
Acoustic neuromas are benign tumors arising from the covering of the nerves that compress the nerves as they grow, causing progressive deterioration in function. Often small in size, they are often only detectable by MRI with gadolinium (contrast agent), in which the balance nerves are clearly visualized inside the back of the skull (posterior cranial fossa and internal auditory canals). Asymmetrical hearing loss is often the only symptom until the tumors reach a large size. Treatment includes observation, surgical removal, and a special form of radiation therapy (Gamma-knife or focused-beam radiotherapy). Any tumor within the posterior cranial fossa or brainstem can cause dizziness, and is most reliably found by an MRI with gadolinium.
Stroke and Transient Ischemic Attacks
Impedance of blood flow, either transiently (TIA) or permanently (stroke), can result in vertigo and imbalance. Risk factors such as elderly age, hypertension, diabetes mellitus, smoking and high cholesterol help lead to the diagnosis. Evaluation of the arteries in the head and neck can be accomplished with ultrasound (good at evaluating the neck arteries), MRA (called an MR angiogram), or conventional angiography (Xrays after injecting contrast). There are many other causes of dizziness and this section is not intended to represent a comprehensive list. Neurologic diseases (e.g. Multiple Sclerosis), medication side effects, auto-immunity disorders, and bacterial infections are an example of other, but less frequent, causes of dizziness. We recommend a complete and thorough evaluation by a physician or a specialist for appropriate diagnosis.
Characterized by recurring bouts of spontaneous vertigo lasting for several hours. Usually associated with hearing loss, tinnitus, and fullness in one ear. Atypical forms can cause only hearing loss or only the vertigo spells. Due to hypertension in fluid filled sacs of the inner ear. Not hereditary. Treated primarily by a low salt diet and diuretics with expected resolution of the vertigo and often improvement in hearing. Approximately 10% of patients will require surgery for relief of symptoms. Research currently focusing on injecting drugs into the affected ear are currently underway. Surgical management includes destruction of the inner ear (labyrinthectomy) for the deaf ear, and in those patients with residual hearing, shunting and nerve sectioning are considerations. The endolymphatic shunt involves opening the bone behind the ear and opening an outpouching of the inner ear, called the endolymphatic sac, in the effort to relieve pressure. This is an outpatient procedure, performed in less than an hour, with a rapid recovery. Success rates vary by surgeon and range between 50-80% success in controlling vertigo. Vestibular nerve section involves cutting the balance nerve inside the skull, usually involving a neuro-otologist and a neurosurgeon. The surgery lasts approximately two hours and requires 2-3 days in the hospital for recovery. Complete recovery from imbalance following surgery can take 1-3 months. Success in relieving vertigo approaches 100%.