Q: My hearing dropped suddenly and my doctor isn’t sure why. Is there a known cause for this and is there a cure for it?
A: Hearing can drop suddenly for a number of reasons, but the type of drop is what is more important. So are the conglomerations of several other symptoms that may or may not occur along with the drop in hearing. In North America, the tendency is for family physicians to make certain assumptions; the most common of which is Otitus Media, otherwise known as a middle ear infection. For this the standard treatment is a course of anti-biotics for a week or two which, when this is the proper diagnosis, clears the problem up fairly quickly.
Since OM is the most common ear ailment, especially in children under 10, it isn’t a bad assumption. Often OM is not necessarily visible by simply using an otoscope to check the ear canal and tympanic membrane, (ear drum). If we were to run a hearing test on a person with a moderate middle ear infection, we would indeed find a hearing loss that is conductive in nature, assuming the hearing was normal before the infection. To give you an illustration of a conductive hearing loss, imagine water in your eaves trough after a rain. If your eaves have leaves covering the drain the water is kept from draining at the same rate it would if there was no blockage. Some still gets through, but most of it backs up behind the blockage, even though there is nothing on the other side of the blockage to kepp the water from flowing. Conductive hearing loss works in a similar way; the fluid building up behind the ear drum doesn’t allow the proper vibration of the eardrum and tends to back up the sound, allowing less of it to transfer to the cochlea, where the nerves take the information to the brain. As with your gutter, if you clear the leaves, the water flows again; with the ear, you drain the fluid and the ear hears again.
The situation gets more complicated when the problem isn’t in the middle or outer ear. Sudden Sensorineural Hearing Loss, (SSNHL), is a far bigger issue and can require much more immediate attention, for particular issues. These issues are rare, but if they occur, treatment is most effective within 72 hours of the loss occurring. That’s three days, and if you can’t get to your family doctor within that time frame, the treatment may be too late.
Luckily, most cases of SSNHL resolve themselves without treatment in anywhere from a few days to a couple weeks, and there are very specific guidelines for those that are more serious, (Colucci, Dennins A., 2013). But when you aren’t sure, where do you go with such little time to do anything?
Start here. Go to a hearing clinic and get the full test done. Anyone who is competent will perform several tests including typmanometry and both air and bone conducted testing of both ears. Tympanometry measures how mobile the eardrum is, and should be part of any standard hearing test. If there is fluid behind the eardrum, the membrane won’t have sufficient mobility to transfer sound and a graph will show a flat line. This is an indication that OM may be the problem. Otherwise, if tympanometry is normal, the rest of the testing will reveal other issues and a decision can be made to get you to an ENT, (Ear, Nose and Throat surgeon), or if necessary, an emergency room. Remember there is a 72 hour window, but the sooner the better. On weekends, or if getting a hearing clinic appointment is longer than 3 days, (rare, but it happens), go immediately to an emergency room. Often they will send you to someone like me to get tested anyway, but they decide if it’s worthwhile taking the medication regardless of the results or if it can wait until they get results. Always ensure that tympanometry is conducted, because that alone can rule out most of the serious issues.
If you have any questions about SSNHL or its treatment please feel free to call either of our offices.