Welcome to Module 2, disorders of the outer ear. In this module, we're going to cover the following objectives: first, we're going to understand congenital and acquired disorders of the outer ear. Next, we're going to recognize pathology of the ear canal, including cerumen or earwax impaction. Lastly, we're going to demonstrate some familiarity with available treatments for problems with the outer ear. So, let's start on the outermost portion of the ear. When the ear doesn't develop fully in the first trimester of pregnancy, the baby is born with something called microtia. This term comes from the Latin, micro meaning small and otia meaning ear. In addition to making it sound fairly smart by using Latin words, this can also help you understand the problem that's occurring. It means little ear. This occurs in approximately one to 5,000 births. It's typically unilateral although rarely can occur on both sides. It's typically not genetically inherited, meaning more than 95 percent of children who are affected by this phenomenon do not have anyone else in their family who've ever had a microtia. This problem can be associated with other craniofacial syndromes and these can include asymmetric development of the face or other problems with the surrounding bones related to the ear. As you can see at the very bottom, there's a progression of different microtias. The first is Grade 1. Typically in Grade 1, all of the key structures of the ear are present but they might be in a slightly different form and the overall shape of the ear may be a little small. Grade 3 is actually the most common and in this case, most of the cartilaginous portion of the ear is missing but the lobule or peanut ear is present. This is typically the most common form. When families are faced with this type of problem they may consider consulting both a plastic surgeon to identify or address the outer cosmetic portion of the external ear or a neurotologist such as myself who might evaluate and consider a surgical treatment for this. Microtia is often although not always associated with aural atresia or lack of development of the ear canal. This is a little more rare than microtia and occurs in about one to 10 to 20,000 births. Like microtia, it's most often unilateral or occurring on only one side. In very rare cases, it can occur on both sides. A fascinating development related to these two abnormalities of the external ear have to do with the embryologic origin. Because the external ear and the ear canal develop from totally different portions of embryologic development in utero, it's possible to have a normal ear with an absence of an ear canal or an ear canal with an abnormal external ear. The way this is determined is both by physical exam as well as an audiologic test. When the ear canal is absent, in this case, aural atresia as you can see on the diagram, this results in a conductive hearing loss. In order to tell what structures might be present because it's not possible to look in the ear and see, we have to use radiologic imaging. The most common test used is something called computed tomography or a CT scan and that enables us to see what portion might be missing and what portion might be there. Typically, the treatment for this problem could include a specialized kind of hearing aid or surgical correction where we create a new ear canal. Let's move on to acquired disorders of the outer ear, and this is a traumatic ear deformity that's often called "cauliflower ear." Now, obviously, that does not come from the Latin but typically comes from the way that the ear looks after it's been subjected to some trauma. There are tight vessels that traverse the skin and cartilage of the ear. Whenever trauma or something hits the ear, these vessels can break and this can cause a buildup of blood or a hematoma between the two layers of the external ear. In fact, this hematoma can both cause necrosis or damage to the underlying cartilage and conversely can also cause hypertrophy or an increase in cartilage or fibrosis. Both of these processes ultimately lead to what we see externally as cauliflower ear. Whenever there's been a trauma to the ear and a potential buildup of blood or a hematoma, it's necessary to get fairly emergent treatment for that where the blood or the hematoma is evacuated by a specialist. This is common but only in those individuals that have repeated trauma to the ear, so we often see it in wrestlers. Another acquired problem of the outer ear is much more common and that is of cerumen or earwax impaction. So, cerumen is normal. In fact, it has lots of great properties including antibacterial, antifungal, and lubricating. It normally moves through the ear canal with the natural process of skin sloughing or chewing or even talking. It's made by the lateral cartilaginous portion of the ear canal. When individuals try to clean their ear, they might be pushing this ear wax deeper into the ear canal to the bony portion or even up to the ear drum. This can sometimes cause injury to the ear. Sensations of your ear being blocked or full of ear wax could include pain or even blockage of hearing. If you feel that your wax could be a problem, it's possible to try some over-the-counter natural treatments such as an ear wax softener, including mineral oil or hydrogen peroxide. If this doesn't help, moving to Q-tips is usually not the best next step. In fact, the best step is to see a physician or someone who's able to clean your ear out under direct visualization. This allows removal of the blockage or the earwax without harming any of the underlying structures which can be very important for hearing. Other treatments that you may see out there such as irrigation when water is shot into the ear in an attempt to dislodge the blockage, or even ear candling can actually be very dangerous and I might caution against those. How about something like a foreign body in the ear. Well, medical professionals like to call anything that's not supposed to be where it is a foreign body and we see this not uncommonly in little kids. In fact, as an ear specialist, I've taken all kinds of things out of the ear canal including legos and peas and a long laundry list of fascinating topics. Typically, if something is an organic matter or a bug or something that might decompose, it would cause pain and that's experienced as otalgia or an earache. It could cause aural fullness which is ear blockage, otorrhea which is fluid draining from the ear, and it can cause hearing loss as well. Whenever the history suggests that there might be a foreign body in the ear canal, it's necessary to see a doctor to confirm if that's the case and the treatment requires removal under direct visualization. In adults and in many individuals, this can be done in a doctor's office, but for little kids, it's often necessary to put them to sleep so we can carefully remove the foreign body or object in their ear without causing any surrounding damage. So, how about some common infections of the ear? Well, otitis externa, otherwise known as swimmer's ear, kind of explains it in itself. This is something that often manifest in individuals that have had repeated or are in individual water exposure. The symptoms related to this disorder include otalgia, ear pain, puritis or itching, ear drainage or otorrhea which can often be foul-smelling, and a sensation of the ear being blocked or full. The diagnosis of this problem requires visualization by a physician and when we look inside the ear, we see exactly what's depicted there on the diagram. That normal nice skin of the ear canal over both the cartilaginous and bony portion becomes red and inflamed and indicates that there's an infection. Often, we can see some white or yellow exudate which is actually pus or purulence in the ear canal. Typically, that your drum itself is intact and not abnormal and this actually helps us quite a bit in the diagnosis of this particular abnormality. There are number of bacteria and even fungus that are commonly associated with otitis externa or swimmer's ear and those can include pseudomonas, staph aureus or various fungus. It's notable because these are different bacteria then cause ear infections or otitis media. We're going to talk about that in the next module. Knowing with which pathogens might affect the problem implicate directly what treatments we might use in that particular case. The treatment of otitis externa or swimmer's ear is typically a topical medication that could be directed at one of the pathogens I just mentioned. Historically and even now, just acidifying the ear canal can also prevent the progression of infection. Typically, the ear canal likes to sit in an acidic or lower pH and so over the counter things such as peroxide, or apple cider vinegar or a number of various easily acquired topical treatments can help you acidify the ear canal. For individuals that have a lot of water exposure, many pretreat with this so as to prevent development of infection. Oral antibiotics or pills by mouth are only necessary when the cartilage of the external ear is affected. You remember that the ear canal was partially cartilage and so when the infection has involved that cartilage, it can extend the external ear and this is more common in individuals who are immunocompromised or who have diabetes. Perhaps the most important portion of the treatment of this problem is to avoid water exposure at all costs while you're undergoing treatment. Now this is a really common problem, swimmer's ear affected by many many people and it's easily treated with these topical antibiotics or other treatments mentioned. In some severe cases, it can extend to the surrounding bone. In that case, we call it malignant otitis externa or skull base osteomyelitis. We don't use the term malignant because it refers to cancer but because it refers to a very severe problem. As we discussed earlier, the ear canal is closely related to a lot of surrounding bone and this bone occurs at the skull base where a variety of nerves and other important structures traverse. This can result in facial paralysis or other abnormalities of the surrounding nerves. This is not treatable with topical treatment and typically requires intravenous antibiotics which can often be necessary over a long period of time. In fact, there is a significant mortality based on this severe infection. In summary, in this module, we covered the pathology of the auricle and the ear canal and we discussed that it can be congenital or something that you're born with, acquired, or even infectious. Cerumen or earwax is normal and it doesn't require routine or daily cleaning. Otitis externa is a common infection of the external ear. It can become more serious in individuals that are diabetic or immunocompromised. Thank you so much for joining us and I hope to see you in the next module.
