Download Anatomy of the ear

Surfer’s ear (Bony Exostoses of the External Auditory Canal)
by Bart Willems and Christo Oosthuizen
Surfer’s ear is a condition in which there is bony overgrowth of the external ear canal
caused by repeated exposure to cold, wet conditions. It is so prevalent in the surfing
community that we even got the naming rights – Surfer’s ear. Surfer’s ear also occurs in
other disciplines that get their ears cold and wet. In the long term it can cause the canal
to narrow, which in turn causes water to become trapped and increases the risk of
infection and hearing loss. As is the case with most medical conditions, prevention is
better than cure, so the ear’s exposure to cold wet environments should be reduced by
using earplugs or neoprene hoods. If the canal is so significantly reduced that above
mentioned complications are a recurring problem to the patient, the canal can be enlarged
surgically. Swimmers ear is a different medical entity that refers to infection of the ear
canal. It is part of the complications of Surfer’s ear, but can also occur independently…
The external auditory canal (ear canal) is one of the only places in the human body where
skin lies directly over bone, lacking any insulation in the form of fat or connective tissue.
Surfers who surf at cold water breaks (<15 degrees Celsius / < 60 Fahrenheit) are 5 – 6
times more likely to develop exostosis compared their tropical counterparts. Repetitive
exposure to cold environments – not only water, but also wind in the case of kayakers over a long time (years) stimulates bone growth in the external auditory canal. The rate
at which the bone grows is proportional to cold exposure time. The most common age to
develop complications that need surgery is the late 30’s. In a normal adult the canal is
about 26mm long and 8 -12mm wide. Over time, if no precautionary orprotective
measures are taken, the canal will become narrower and eventually completely obliterate.
The symptoms a person with bony exostoses in the external auditory canal experiences is
related to the percentage of canal taken up by the bony growths – normally becoming a
chronic problem if the remaining canal is <2mm.
Symptoms appear gradually over years as the canal becomes progressively narrowed.
Mild exostoses is usually asymptomatic, but over time growth of the bone causes the
canal to be narrow enough to interfere with its normal cleansing ability. Skin debris,
earwax, moisture, water and sand can all accumulate behind the narrowing causing
hearing loss and inflammation. The trapped material, body temperature and lack of
sunlight create an ideal environment for bacterial and fungal growth. Infection and
inflammation leads to swelling, pain and even the formation of pus. This causes further
swelling and pain that exacerbates the problem. Once this stage is reached the condition
becomes progressively more difficult to treat as there is minimal space to clean the ear
and the much needed ear drops/ointments are often unable to reach the affected area.
Prevention
In the case of Surfer’s Ear, prevention is far better than cure. Because of the slow,
progressive nature of Surfer’s Ear it is important that anyone planning to enter cold water
regularly should start protecting his / her ears early, while the ear canal is still normal.
Protection meaning, creating a barrier between the ear canal and the cold – be it water or
air – to keep the ear warm and dry.
This can be done by using earplugs. There are numerous different possibilities on the
market, but Blutac / funny putty or moldable silicone earplugs that is available at a
pharmacy or sport shop, will be sufficient. It is possible to get custom made earplugs
molded specifically for your ears. The advantage of these is that some of them have a
tiny canal that lets sound waves pass through thereby improving your hearing. Neoprene
hoods are also an effective way to keep the ears warm and slow the growth of the
exostosis. It is also important to maintain good ear hygiene (explained in the Swimmer’s
ear section).
Treatment
As mentioned above the biggest complication of Surfer’s ear is recurrent infections of the
external ear canal. In the early stages of the disease this can be treated medically with ear
drops/ointments. It is therefore advisable to attend your G.P sooner rather than later.
However as the disease progresses these measures become less effective and the only
alternative is a surgical procedure called a canaloplasty. There are different methods and
approaches to this procedure. Some surgeons make an incision behind the ear and flap
the ear forward to then excavate the bone from the narrowed canal with a high-speed
drill. It is also possible to approach the canal directly. Other surgeons prefer to use a
mini chisel (1mm) to chip away the bony overgrowth. Either way you’ll need to go to the
hospital for a day or two, get a general anesthesic and stay out of the water for 6 – 8
weeks to keep the ear dry. With all surgical procedures there are potential complications
involved and in this case it could include infection, non-healing and loss of hearing.
After surgery, if everything did go perfectly according to plan you are still not cured.
Exostosis tends to grow back 3 – 6 times faster after surgery. Bottom line is – protect
your ears from the cold to protect your ears from surgery.
Swimmers Ear (Otitis Externa)
by Bart Willems and Christo Oosthuizen
Swimmer’s ear is a condition characterized by inflammation of the external ear canal
often contracted by swimmers whose ears are irritated by chlorinated water or infected by
dirty water. In contrast to Otitis Media that occurs in the middle ear, Otitis Externa
occurs outside of the tympanic membrane (ear drum). It is a common cause of itchy or
painful ears. Otitis Externa is more common in patients affected by Surfer’s ear as this
causes water to stagnate and prevents the ear from drying. Infection can cause hearing
loss in the acute phase and possibly spread locally to adjacent structures. Swimmers ear
is prevented by keeping ears dry and to minimize exposure to infected water sources by
using plugs. Prevention can further be assisted by the correct eardrops. Swimmers ear is
medically treated.
The normal ear canal is a fantastic structure that relays sound from the outside to the
middle ear as well as protecting the delicate structure of the middle ear. It produces wax
(cerumen) that forms a protective barrier between the skin and the environment. It is
self-cleansing in most cases and pushing any foreign object into the ear (e.g. cotton ear
buds) is highly discouraged. (It is said that the only safe object to introduce into your ear
is your own elbow…)
Otitis externa is inflammation of the external auditory canal (ear canal). The acute form
is commonly found in surfers. This can be complicated by infection with bacteria like
Pseudomonas Aeruginosa and Staphylococcus Aureas; or fungi such as Aspergillus and
Candida. Numerous reasons make surfers more prone to Otitis Externa. Trauma to the
ear canal (e.g. scratching the wax off the delicate skin causing abrasion), repeated
moisture in the ear and foreign bodies and substances are the main initiating factors of
Swimmer’s Ear. This is further aggravated if the water is dirty e.g. close to the storm
water outflow of a town. With the above kept in mind it is then simple to deduct that
Surfers’ ear, as described on another part of the book, is a condition that predisposes to
Otitis Externa.
Symptoms
Otitis Externa usually starts off as an uncomfortable itchy feeling of the external ear
canal. Mild redness and scaly skin can be seen at the mouth of the canal. It can then
progress to a stage where it is very painful, especially when the auricle (ear shell) or
tragus (the little protrusion in front of the ear canal) is touched or pulled. This pain upon
movement of the ear is one of the distinguishing factors of Otitis Externa and can help
you to differentiate it from Otitis Media. Further complications are hearing loss,
discharge from the ear and severe local infection that can spread to surrounding
structures.
Treatment & Prevention
The condition can be partially prevented by keeping the ears dry by using earplugs. If
your ears do get wet, a couple of drops of a mixture of isopropyl alcohol and white
vinegar (50%: 50%; 1:1) can be instilled into the ear. The volatility of the alcohol dries
the ear and causes bacterial death and the acidic vinegar inhibits bacterial and fungal
growth. Ensure that you can feel the drops reach deep into the canal. A hair drier can
then be used to further dry the ears. It is also recommended to instill a couple of drops of
mineral oil / olive oil into your ear before you go surfing. The oil will form a protective
layer over the sensitive skin, protecting it from dirty water.
The main aim of treatment is two fold: cure the infection and restore the normal internal
milieu of the ear so the skin is in tact and wax production occurs normally. If you start
getting itchy ears its best to keep on using above treatment and stay out of the water for a
couple of days.
If you are experiencing a painful ear it is best to treat it with a topical combination
eardrop or combination ointment. These preparations should contain a steroid, antifungal (Tolnaftate or Clitrimazole) and anti-biotic (Aminoglycosides or
Flouroquinolones). Before that you should be sure that your tympanic membrane (ear
drum) is in tact and most debris is removed from the ear. Usually in a surfer that recently
developed the condition, if it is not yet severe, and if there is no history of trauma, we can
assume that the tympanic membrane is in tact. First the mixture of alcohol and vinegar is
instilled (a mixture with a higher percentage alcohol can be used). The ear is then dried.
Combination eardrops can then be instilled or ointment can be put on a gauze wick and
inserted into the ear. When instilling eardrops the patient should lie on his side with the
head horizontal and time should be given for the eardrops to migrate to the deepest part
of the canal (pumping the tragus can assist penetration). It is best to have an assistant to
help you with this process. Treatment should continue for up to 10 days (or 3 days after
symptoms have resolved) and the ears should be kept completely dry (even take
precautions when washing your hair). If you have a severe or persistent infection it is
better to add an oral antibiotic to the topical treatment.
Other problem in the external ear: an earwax jam or plug. This is when the canal is
obstructed by accumulation of earwax. A few drops palm warmed mineral oil or olive oil
should be instill into ear and irrigate carefully with 30 degree water a day or two later.
Do this over a basin so you can judge the success by observing what comes out.
Tympanic membrane rupture (ruptured eardrum)
by Bart Willems and Christo Oosthuizen
A ruptured tympanic membrane is another condition often contracted by surfers. This
can happen when the side of the head including the ear hits a flat surface, like the face of
a wave, with significant force and speed, not allowing air to escape from the ear canal.
The air is compressed inward and causes the delicate tympanic membrane to rupture into
the middle ear space. The tympanic membrane can also rupture if you are pushed deep
under water and you are unable to equalize.
Symptoms include acute pain, hearing loss, tinnitus (a constant tweeting sound in the
ear), vertigo or loss of direction and also bloody discharge from the ear. A ruptured
tympanic membrane usually heals spontaneously. In the case of a surfer is recommended
to see a doctor to remove any dirt / foreign material from the ear. A short course of
antibiotic eardrops is also recommended. Great caution should be taken to keep the ear
dry until the tympanic membrane has healed. A neoprene hood can protect the ear
sufficiently to reduce traumatic rupture of the tympanic membrane.