There are three main parts to the ear: the outer ear, middle ear, and inner ear. The outer ear consists of the pinna or auricle and the ear canal. The ear canal is shaped like a curved tube and at one end lies the eardrum. The eardrum serves to separate the ear canal from the middle ear space, which contains the three bones of hearing. When sound waves vibrate the eardrum, the hearing bones transmit this sound to the fluid of the inner ear, ultimately creating a nerve impulse that travels through the hearing nerve to the brain.
Skin naturally lines the ear canal and makes up the outer most layer of the eardrum. In some individuals, the eardrum is pulled inward (or sunken in), creating a small pocket. Since the normal skin lining of the ear canal and eardrum tends to ‘shed,’ skin may accumulate in this pocket. Over time and with continued accumulation, the pocket may increase in size and expand further inward into the structures of the middle ear, forming what is known as a cholesteatoma, or collection of skin. These cholesteatomas may also form as a result of skin growth through a perforation in the eardrum and are present at birth (a congenital condition) in a small number of people.
Cholesteatomas usually continue to enlarge, often times leading to hearing loss, dizziness, destruction of the hearing bones, facial nerve damage, and, in rare situations, erosion of the bone that encloses the brain. As a general rule, cholesteatomas require surgical removal and will not resolve with medical therapy alone.
Sudden Sensorineural Hearing Loss
Sudden sensorineural hearing loss is a term used to describe hearing loss that develops over a very short period of time. Sensorineural hearing loss generally implies damage to the structures of the inner ear or hearing nerve. This should be distinguished from conductive hearing losses, which are the result of problems with the hearing bones, eardrum, and middle ear space. While there are many possible causes of sudden sensorineural hearing loss, in most cases, the cause is unknown.
Technically speaking, sudden sensorineural hearing loss is defined by a hearing loss of 30 decibel (a measure of volume) in three consecutive frequencies occurring over a period of 72 hours or less. In actuality, sudden sensorineural hearing loss may occur with smaller degrees of hearing loss and may have associated changes in one’s ability to understand the clarity of words.
In addition to a sudden drop in hearing (which can occur over a brief instant or over a period of hours), patients with sudden sensorineural hearing loss may experience ringing or noise within the ear and some sense of dizziness or imbalance. The presence of any additional neurologic symptoms (such as slurring of speech, confusion, or weakness of the face, arms or legs), although rare, would suggest that a brain stroke might be occurring and would require emergent evaluation at a hospital.
Patients who experience a sudden drop in hearing should be seen immediately, preferably by an ENT physician or Neurotologist, and a complete hearing test should be performed to determine the extent of the hearing loss. Oftentimes, patients attribute their ‘clogged ear’ to a cold or allergies. However, if there is any question of a sudden drop in hearing, it is better to have it checked as soon as possible. Treatment is often available, usually in the form of steroid medications, but is much more effective if provided as close in time as possible to the sudden drop in hearing.
Otosclerosis is a disorder that affects the mobility of the third hearing bone (the stapes). Over time, otosclerosis causes the stapes bone to become hardened and fixed in place. As a result, sound cannot be transmitted to the inner ear and hearing loss results.
Otosclerosis is a common cause of hearing loss. The hearing loss is usually a conductive hearing loss, which means that the inner ear (nerve) function remains normal and the hearing loss stems from blockage of sound transmission into the inner ear. However, in some instances, persons with otosclerosis will have a mixed hearing loss. This means that they have both a conductive hearing loss and a sensorineural hearing loss, which results from loss of inner ear or hearing nerve function. In general, Caucasians are more affected by otosclerosis than other races while women are affected nearly twice as much as men. Genetic factors are known to play a role in many cases of otosclerosis. As a result, it is not uncommon for persons with otosclerosis to have relatives with hearing loss. Hormonal factors are also felt to be important in otosclerosis as during or following pregnancy, some woman with otosclerosis will notice a decrease in their hearing.
The most common symptom of otosclerosis is a gradual decrease in hearing. Otosclerosis often affects both ears, though one ear may develop hearing loss many years prior to the second ear. Other symptoms include difficulty understanding speech, ringing or noise in the ears, and occasionally, dizziness or imbalance.
There are several treatment options available for otosclerosis. In addition to the degree of hearing loss in the affected ear, the hearing level of the opposite ear must always be considered. (For example, patients with otosclerosis in one ear and deafness in the other ear should not undergo stapedectomy surgery). With this in mind, let’s discuss the available options for otosclerosis.
One treatment option is observation. This essentially means, ‘do nothing.’ While persons may elect to ‘observe’ their otosclerosis, hearing loss will likely progress with time. We do recommend routine hearing tests during any period of observation.
A second option is medical therapy. Sodium fluoride is a medication that is sometimes used to help prevent further progression in certain cases of otosclerosis. This is usually given as a combination of fluoride and calcium (called Florical) and is believed to help prevent further changes in the bone caused by otosclerosis. However, there are no known medical treatments that can improve or recover hearing in otosclerosis.
The third option is use of a hearing aid. Most patients with otosclerosis can benefit from the use of a properly fitted hearing aid. Hearing aids do not carry the risks associated with surgery, but do have some disadvantages, including cost, unnatural sound quality, cosmetic concerns, and a need to wear the aid to hear.
The fourth option is surgical correction. The surgery for otosclerosis is called a stapedectomy and is designed to improve the conductive hearing loss of otosclerosis. This elective procedure involves removing part (or all) of the base of the stapes bone (called the footplate) and placing a prosthetic ear bone to re-establish the connection between the second ear bone (the incus) and the inner ear. In addition to very fine ear instruments, specialized lasers and drills are used to perform the surgery. This can provide a lasting, natural hearing result in many cases. However, stapedectomy surgery carries some risks, including infection, ringing, taste disturbances, and dizziness, among others. In a small percentage of cases, hearing loss may occur following surgery for otosclerosis. A full discussion of the risks and benefits of surgery is required before any patient elects to proceed with surgery.
The information and reference materials included on this website are intended solely for the general information and education purposes of the reader. It is not intended nor implied to be a substitute for professional medical advice or to diagnose health problems. The reader should always consult his or her healthcare provider to discuss the information presented here.