Eustachian tube dysfunction

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Eustachian tube dysfunction

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A 6-year-old boy is brought to the pediatrician for evaluation of left ear pain. The patient's mother states, “He has been tugging on his left ear for the past three days; he just cannot seem to get any relief.”  The patient has been taking tylenol at home for symptomatic relief. Temperature is 38.0°C (100.4°F), pulse is 99/min, respirations are 16/min, and blood pressure is 100/65 mmHg. Physical examination is notable for the following finding:


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Which of the following pathogens is the most likely cause of this patient’s clinical presentation?

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The ear can be broken into three sections.

The first is the outer ear which is the part you see called the pinna as well as the ear canal.

Next is the middle ear, which is a tiny chamber that houses the tiny ear bones—the malleus, incus, and stapes.

And finally there’s the inner ear, which contains very special tissue structures called the cochlea which converts sound waves into electrical impulses for the brain and the semicircular canals which help with balance.

Between the outer and middle ear is an eardrum, also called the tympanic membrane, so no air passes between the two areas.

But the middle ear does have another possible outlet, called the eustachian tube which acts like a valve connecting the middle ear to the nasopharynx.

This tube has three main functions—equalizing pressure across the tympanic membrane, protecting the middle ear from reflux of fluids going up from the nasopharynx, and clearing out middle ear secretions.

Eustachian tube dysfunction describes situations when one or all of these functions aren’t happening normally.

In an adult, the eustachian tube is a roughly 4 centimeter long part-bone, part-cartilage canal that’s surrounded by four key muscles: the tensor veli palatini, the levator veli palatini, the salpingopharyngeus, and the tensor tympani, and it’s those first two that help a lot with opening up the tube.

Actions like chewing, swallowing, and yawning all pull on those muscles to help open up the eustachian tube.