Ear Infections, Hearing and Ear Tube Surgery
What is an ear infection?There are several types of "ear infections". However, routinely an ear infection usually refers to Otitis Media, a bacterial infection of the middle ear. There are three main parts of the ear- the outer ear, the middle ear and the inner ear. The outer ear is comprised of the pinna (the part that protrudes from the head) and the ear canal, which extends from the pinna to the eardrum. The ear canal is where earwax accumulates. The middle ear is the area behind the eardrum. This space is drained and ventilated by a structure called the Eustachian Tube, which runs from the back of the ear to the back of the nose. The inner ear is deep inside the skull, and is where the nerves and other structures controlling hearing and balance are located. It is rarely affected by ear infections.
In the case of Otitis Media, the middle ear fills up with infected fluid (pus). This can cause pain, fever, irritability in children and a temporary hearing loss. The diagnosis is made by seeing pus behind the eardrum. Adults and children with ear infections almost always have some problem hearing because the fluid interferes with vibration of the eardrum. Acute Otitis Media is often treated with antibiotics, although recent research suggests that in some cases, it may be appropriate to treat the pain and check frequently to see if the ear infection resolves.
The Appearance of an Ear Infection
Another common type of ear infection is Otitis Externa, or "swimmer's ear", an infection of the skin of the ear canal (outside of the eardrum). The ear canal is a warm, moist place which is not easily cleaned, and a superficial skin infection can linger in this region. These patients have ears which hurt when moved and which itch severely. Otitis Externa is usually treated with ear drops containing an antibiotic and possibly a steroid, but it is usually important to thoroughly clean the ear, using a microscope and suction. Cleaning is NOT something that should be done by anyone but a doctor with experience in this procedure. Do not try to clean the ear yourself, this may make things worse. In severe cases of Otitis Externa, oral antibiotics are also used.
|The Appearance of Swimmer's Ear|
Although middle ear infections and swimmer's ear can both be present at the same time, they generally have nothing to do with each other. In some cases, though, if there is a hole (or ear tube) in the eardrum, fluid can drain from a middle ear infection into the ear canal, causing swimmer's ear. If there is no hole, the eardrum is watertight. Therefore, getting water in the ear canal from swimming or bathing cannot cause Otitis Media or any other type of middle ear fluid. While occasionally excessive water exposure can cause swimmer's ear, this should not be confused with a middle ear infection. They are different problems and are treated differently.
Why do children get more ear infections than adults?The main reason why children get more middle ear infections (Otitis Media) is poor functioning of the drainage pathway (the Eustachian Tube) that connects the middle ear to the back of the nose. This tube is the body's natural way to ventilate the ear, to allow fluid to drain when the ear is infected, and to allow air to enter the ear and keep it healthy. A child's Eustachian tube does not function as well as an adult's tube for a variety of reasons, the most important being that a child has a straighter Eustachian Tube than an adult so it does not drain as well. It is also easier for secretions to flow from the nose into the ear and become trapped and lead to an ear infection. Most children outgrow problems with their ears by 8 to 10 years of age.
In addition to problems with the Eustachian tube, young children have immature immune systems and may be exposed to other sick children in a school or day care setting. Upper respiratory tract infections, such as colds, are more common in children; consequently, a child's Eustachian tube often functions worse as there may be swelling in the Eustachian tube from recurrent infections.
Allergies are common in children, but there is not much evidence to suggest that they are a primary cause of either ear infections or middle ear fluid. While allergies can and should be treated, this treatment may not have a significant effect on ear disease. Many people assume that bottle feeding, milk products or pacifier use can contribute to ear disease, but again there is not much evidence to support these theories.
Young children do have large adenoids as compared to older children and adults. The adenoids are a pad of tissue like a tonsil in the back of the nose which can block or contaminate one end of the Eustachian tube. The adenoids are also a minor contributing factor to ear disease in children, as discussed below.
Can my child catch an ear infection from another child?Ear infections are not contagious, but are often associated with upper respiratory tract infections (such as colds). Such an infection causes swelling in the lining of the nose and the natural drainage pathways of the ears (the Eustachian tube), which make ear ventilation worse and an ear infection more likely. Also, bacteria or viruses can move from the nose to the ear through the Eustachian tube. If your child simply has an ear infection but no cold symptoms, he or she is not necessarily contagious.
What is the difference between fluid in the ear and an ear infection?Otitis Media (middle ear infection) means that the space behind the eardrum (the middle ear) is full of infected fluid (pus). If there is no fluid, there is no ear infection (no matter how red the eardrum appears).
Sometimes, the fluid behind the ear is not infected, but instead is clean ("sterile"). This can happen after treating an ear infection with antibiotics, or it can occur without any previous infection. Sterile fluid can be clear, yellow, thick, thin, or filled with bubbles. Sterile middle ear fluid (also known as an effusion) and Otitis Media can occur in the same child at different times. This is because the underlying cause (poor ventilation through the Eustachian tube) is the same in both conditions.
|Middle Ear Effusion|
How do ear infections and fluid affect hearing?
Any time the ear is filled with fluid from either an infection or sterile fluid, there will be a temporary hearing loss. This is because the fluid interferes with the transmission of sound through the middle ear to the inner ear where the hearing nerve is found. Hearing will almost always return to normal when the fluid goes away.
What does it mean when there is "low pressure" behind the eardrum?The poor ventilation of the middle ear by the immature Eustachian Tube can cause fluid to accumulate behind the eardrum (as described above). However, sometimes the ventilation is not bad enough to cause fluid to develop, but can result in lower pressure behind the eardrum than that in the surrounding environment. This causes the eardrum to be drawn in, or partially collapsed. While this condition is caused by the same underlying problem (poor ventilation), and can cause the transmission of sound through the ear to be less efficient (just as with ear fluid), it is a more limited problem, and usually the hearing is significantly affected. In prolonged and severe cases, the collapse can cause damage to the eardrum. Think of the eardrum like a piece of plastic wrap over a bowl. When you put the bowl in the microwave to heat it up you put holes in the wrap to allow air to enter. If you don't the plastic wrap is sucked down into the bowl and eventually will dissolve. The same process can happen to the ear drum if negative pressure is severe and left untreated for a prolonged period of time.
Should ear wax be removed? Will it cause a problemEar wax (cerumen) is a normal bodily secretion, which protects the ear canal skin from infections like swimmer's ear. A small amount of it is normal and necessary to keep the ear canal healthy. Overcleaning the ear can predispose adults and children to infections of the ear canal. Using a cotton tipped applicator (such as a Q-tips) can also pack the wax deeply in the ear, or even puncture the eardrum, making the situation much worse. Please discuss techniques for the management of ear wax with me at your next visit.
Ear wax rarely causes hearing loss by itself, especially if it has not been packed in with a cotton tipped applicator. However, it may be necessary for a doctor to clean out the earwax if it is blocking the view of the eardrum. Sometimes, earwax must be removed so that a diagnosis of a middle ear infection can be made, or to help treat swimmer's ear. In this case, it should be done by someone with the necessary tools and experience. This can be very difficult in young children who are frightened and struggling or in adults who are very sensitive to manipulation of their ear canal and this process is potentially dangerous if incorrectly performed.
What can be done about recurrent ear infections?Ear infections are usually treated with antibiotics. In many cases, the "milder" antibiotics (such as amoxicillin) no longer work when the bacteria become resistant to them, and "more powerful" antibiotics must be used. Although a variety of allergies can contribute to swelling in the lining of the nose and in the drainage pathway of the ear (the Eustachian tube), allergies alone have not been shown to be a major cause of ear infections or ear fluid.
In the past, one approach to recurrent ear infections was prophylactic (preventative) antibiotics. This was a low dose of an antibiotic given for a longer time (1-3 months) to keep bacteria from gaining enough of a foothold in the middle ear to cause infection. This is rarely used now, because of concerns about the bacteria becoming resistant to prolonged antibiotic use.
For children who have multiple ear infections in a year, placement of ear tubes (see below) may be recommended to reduce the need for antibiotics, and prevent the temporary hearing loss and ear pain that goes along with infections.
|Pressure Equalizing Tube|
|Pressure Equalizing Tube|
What can be done about fluid in the ear without infection?
A "sterile" effusion (no infection) may follow the successful treatment of an ear infection. This fluid will usually go away by itself as the body's own natural ventilation pathway (the Eustachian tube) gradually drains the ear. In other cases, the fluid may be present for many months without any history of infection.
Medical treatment in some cases can be effective in treating ear fluid. It may be recommended to use antihistamines or nasal sprays to improve drainage from the nose and Eustachian Tube. However for children who have persistent middle ear fluid for more than a few months, it may be beneficial to place ear tubes (see below). This is especially helpful in cases where the hearing loss is contributing to speech or learning problems, or in cases where there are other underlying problems such as developmental delays.
How does surgery help children with recurrent ear infections or persistent ear fluid?Some children with persistent ear fluid or many ear infections may be offered surgery, to place a small drain through the eardrum. This operation is known as BMT, for Bilateral (both sides) Myringotomy (the hole in the eardrum) and Tubes (the drain placed through the hole). The tubes themselves are known as pressure equalizing tubes (PET). Although there are many factors which go into the decision to operate, BMT is typically recommended after many ear infections in a year if ear fluid has been present with hearing loss for several months or if there is any damage to the ear drum from persistent fluid or negative pressure.
Pressure Equalizing Tube Bypassing the Eustachian Tube
It is important to remember that the tube does not "fix" the underlying problem (immature Eustachian Tube function and poor ear ventilation). No surgical intervention can fix this except growth and development. While some children take longer to grow out of ear disease than others, very few children still have this problem past age 8. The tubes simply act as a "way to buy time" as the child grows or in adults to allow swelling to resolve in adult patients. Ear tubes work by bypassing the problem by ventilating the ears through the eardrum, so that ear infections and ear fluid are prevented. By the time that the tubes come out, most children have grown enough to ventilate their ears on their own - approximately 10 % of children may need to have tubes placed more than once.
There are two basic types of tubes- short acting and long acting. Although there are dozens of styles and brands, most fall into one of these two categories. Each surgeon has his or her own preferences regarding tube selection. Generally, short acting tubes are used in children without other underlying problems (see below) for their first or second set of tubes. These tubes reliably fall out of the eardrum within 6 months to a year after placement.
Long acting tubes are used with children suspected of having severe, long-term Eustachian tube problems. Such problems may be seen in children with cleft palate, Down syndrome, various head and neck syndromes, or older children who have had longstanding ear problems and severe collapse of the eardrum. While the long-term tubes make replacement surgery less likely, they have a greater chance of leaving a persistent hole in the eardrum after they fall out or are removed, which would then require more extensive surgery to repair. For this reason, I rarely recommend long term tubes in children and only recommend long term tubes in adults if their problems are persistent.
Short Acting Tubes (last 6-12 months) Long Acting Tubes (last 3 years or more)
|Short Acting Tubes|
|Long Acting Tubes|
In some cases removal of the adenoids will be recommended when tubes are placed. The theory behind this practice is that the adenoids sit at one end of the Eustachian tube (in the back of the nose), and may contribute to ear infections and fluid . There are several theories as to why the adenoids have this effect. One of which is that they physically block the Eustachian tube, interfering with its function. Another theory is that they provide a place for bacteria to grow which then inflame the Eustachian tube, or travel up the tube into the ear.
Adenoidectomy adds a small amount of time and risk to the surgery, and like all operations, should not be done unless there is a good reason. Adenoidectomy may be recommended if your child has required a previous set of ear tubes or has symptoms which suggest blockage of the nose by the adenoids such as snoring, mouth breathing or recurrent infections.
What are the benefits of inserting pressure equalizing tubes?In children who have persistent ear fluid, the benefit is immediate. Once the fluid is suctioned from the ear, hearing is improved. Many parents of children with speech delay related to hearing loss will report a quick improvement in language and socialization after surgery. Sometimes, especially if the fluid is thick, drainage from all the small spaces throughout the middle ear may continue for a few days. The ventilation that the tube provides prevents the fluid from coming back, as long as the tube is open.
For children with recurrent ear infections, the tubes make it less likely that the ear will become infected in the future, reducing the need for antibiotics. However, it is still possible to get an ear infection, especially during a cold. In this case, though, the ventilation tube serves to drain the infected fluid out of the ear. Therefore, the child experiences less pain and fever than they would if the tubes were not in place. I will ususally recommend the use of ear drops instead of oral antibiotics if your child does develop ear infection or drainage after tubes are placed. The ear drops are antibiotics and avoid, in most cases, the use of oral antibiotics.
What are the risks of inserting pressure equalizing tubes?The most common problem after tube placement is persistent drainage of liquid from the ear. Although the tube is placed to allow for drainage as well as ventilation, sometimes the drainage continues for weeks and may cause symptoms such as itching or foul odor. In this case, it may require specific treatment such as the use of ear drops. If drainage from the ears does not improve within three days of starting ear drops then a child should be seen in our office for an evaluation.
In rare cases, the hole in the eardrum will not close as expected after the tube comes out. This is very uncommon with short acting tubes, but I recommend that no tube stay in place for more than three years. After three years, the chance of persistent perforation increases and removal of the tube is recommended.
Many parents are concerned about "scarring" of the eardrum. This can be seen after tube placement, or simply after many ear infections. In most cases, scar tissue on the eardrum does not cause any problem at all, and hearing is generally normal once the fluid is gone. Serious injury to the middle or inner ear mechanism during surgery is extremely uncommon.
The surgery to insert tubes is done under general anesthesia. This is usually the most frightening part of the whole process for parents. However, it is extremely safe. While the operation only takes a few minutes, it is vital that the child be absolutely still, as even a small amount of movement could cause damage to the ear to occur. Although tubes can be placed in adults with local anesthesia, it is simply not possible to do this safely in most younger patients.
Doesn't the hole in the eardrum that occurs when tubes are placed cause a hearing loss?In most cases hearing is improved by removing the fluid and allowing sound to travel through the middle ear. The size of the hole is so small compared to the overall size of the ear, that it does not significantly reduce the surface of the eardrum. Even with a tube in place, the drum vibrates well enough for normal hearing to occur.
What do I have to do after the tubes are placed?There is little care that is required after tubes are placed. You or your child will be seen in follow up three weeks after the surgery and then every three to four months so that I may check the ear to assure that no problems with the tubes are developing. You or your child will have a hearing test performed after the tubes are placed and hearing test will be performed intermittently while the tubes are in place to assure that there is no decrease in hearing.
What happens when the tubes fall out?The tube is pushed out as the eardrum grows. As this happens, the tube is designed to fall outward, into the ear canal. Once it is there, it does not cause any harm. In most cases it will work its way out of the canal and fall out of the ear entirely.
Once the tube is out and the hole in the eardrum has closed, the child is once again dependant on his or her own natural ear ventilation to prevent ear infections and the accumulation of fluid. Tubes are placed to "buy time" and allow for ventilation while the child's ears mature; ideally, by the time the tubes are out, the child has outgrown the ear problem that required the operation. However, this is not always the case.
About 10% of children will need a second set of tubes, and a smaller number will need a third set. Such children may have underlying problems which make them take a long time to grow out of their ear disease (such as cleft palate), while others are otherwise normal but just take longer to develop good Eustachian tube function. Long acting tubes make the chances of a second operation less likely, but this benefit must be balanced against the greater possibility of persistent perforation (especially if they are not removed before three years). In each child, a number of factors go into the decision as to what type of tubes to place and whether or not they need replacement.