Through the Otoscope
Those who do diagnostic testing are familiar with the common otitis management and hearing loss aspect of middle ear fluid. Colds and allergies create congestion that spreads through the upper respiratory passages, and often causes Eustachian tube dysfunction. Middle ear fluid, however, also can have a rare but critically important twist; some cases have a dangerous etiology.
You are familiar with the clearance process for patients who are interested in purchasing hearing aids, including the conditions that make ENT evaluation mandatory. Unilateral hearing loss, for example, could be caused by a life-threatening disease such as a brainstem tumor, and middle ear fluid falls in this same category.
One of the most important points to understand is that a unilateral, conductive hearing loss may be an early and the only sign of a nasopharyngeal carcinoma.
A cancer in the nasopharynx often manifests itself by disrupting Eustachian tube function and precipitating middle ear fluid. It is critically important to treat this disease as early as possible. If referral to an ENT is delayed for any reason, the life-saving benefits of treatment may be reduced. It is smart medicine to have an ENT evaluate the patient to be certain there are no growths or abnormalities.
PREVALENCE OF MIDDLE EAR FLUID
Those at the beginning and end of life tend to have the highest percentage of middle ear fluid. Children often have “fluid” because their heads are small and their Eustachian tubes are naturally positioned more horizontally than vertically. A child's immune system is less developed than an adult's, and studies of children in kindergarten have shown a large percentage of undetected middle ear fluid. Geriatric patients also have a higher incidence of middle ear fluid because all biological systems weaken as people age.
Patients with hearing impairment often tell practitioners that their hearing is much worse, blaming it on defective hearing aids or worsening hearing. This complaint should be evaluated cautiously and completely. The typical hearing health office has the tools (otoscopes, air- and bone-conduction tests, tympanometry) to do site-of-lesion testing to assess middle-ear integrity.
A patient with middle ear fluid has “yellow” discoloration behind the eardrum. (See photograph.) This is a mucous-like fluid trapped in the middle ear space by a dysfunctional Eustachian tube. Observe the bubbles; several large ones are seen to the right of the manubrium (the long arm of the Malleus), and several small ones are seen on the far left in the middle ear space. The tympanic membrane is retracted and stiff to pneumotoscopy. The “yellowish” color of this fluid is common, but be cautious: middle ear fluids have a wide variety of colors, and can be difficult to detect visually. Tympanomentry and pneumotoscopy are invaluable tools in assessing patients with middle ear fluid.
If one of your patients has a new conductive hearing loss, do not be talked into fitting him with a hearing aid without an ENT consultation. I have seen patients who had mixed hearing loss who were not referred for medical consultations until it was too late. In one case, three years passed between the time the patient was fitted with a hearing aid and the time he came to see me. This patient lost precious years of his life because treatment was delayed. Don't fall into this trap!
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