Through The Otoscope
Rensink, Michael J. MD
Dr. Rensink is a member of ENT Associates of San Diego, and has been a practicing ENT specialist for more than 35 years.
Special thanks to MedRx for use of a video otoscope to capture the images in this article
Two of my patients have the same problem with their ears and the same diagnosis. (Figures 1 and 2.) One, a healthy 72-year-old man, complained about poor hearing, and was not sure if his hearing aids were working properly. The hearing aids were cleaned, his ears were checked for wax, and his hearing was tested. The test indicated hearing deterioration in both ears. The left ear was impacted with wax, and the eardrum in his right ear looked strange. The other patient's evaluation showed hearing that was close to normal in both ears, and tympanograms were also normal. She denied feeling pain or discomfort in her ear.
An inexperienced practitioner may look at these patients’ ears and be tempted to grasp the tissue to see what happens, but experience teaches otherwise. The tissue may be attached to remnants of a prosthesis or transplanted cartilage, or a cholesteatoma may have grown in the middle ear. Never pull or probe unknown tissue unless you are absolutely sure you know what you are doing and your state license permits such activity. What is your diagnosis? See p. 10.
Diagnosis: Pseudo Eardrum
This diagnosis may be easy if you routinely use an otoscope in your practice, and studied the visual characteristics and landmarks of eardrums in graduate school. But it may be more complex if you are new to the profession and do not have extensive experience using an otoscope.
Figure. Michael J. R...Image Tools
The thin, clear wrinkled tissue you see in Figure 1 and the thin, clear smooth tissue in Figure 2 is dead skin from the patients’ ear canals. The patients in both cases moved this tissue deeper into the ear canal, firmly attaching it to the sides of the canal with a Q-tip. This condition is called pseudo eardrum.
Figures 3A and B show the male patient's ear after I pulled the pseudo eardrum away from the side of the ear canal. A ventilation tube is hiding behind the dead skin. Figure 4 is a photograph of my female patient's ear after the pseudo eardrum was removed. The prominence and manubrium of the malleus are obvious.
Some pseudo eardrums have a realistic appearance, even more than our photographs. It pays to be extremely cautious when dealing with cases like this. The eardrum's concave shape is recreated when dead skin is pushed deep into the ear canal with a Q-tip. The dead skin takes on the shape of the Q-tip, which is similar to the eardrum. Bits of earwax can effectively attach the dead skin in place. The tissues’ wrinkled texture is often missing, and a quick look into the ears might make you believe you are looking at the eardrum.
The main clues in this differential diagnosis are the missing landmarks. When a tympanic membrane is viewed, the prominence of the malleus, manubrium, and umbo should be easily visible. The manubrium is embedded in the upper portion of the eardrum and serves as a prominent landmark in most ears.
Pseudo eardrums create a funny feeling in the ear and, depending on the degree of attachment and associated debris, considerable hearing loss. Pseudo eardrums do not move well with pneumatic otoscopy. Tympanograms are usually helpful but in my male patient's case, the tympanogram is misleading because a ventilation tube is in the eardrum. The flat tympanogram is not helpful in making a diagnosis.
It also helps to have well organized notes and complete medical records. Most patients will remember if they have had a tube placed in an ear, so be extremely cautious when cleaning this ear. Sometimes it is difficult to distinguish between a normal eardrum and a pseudo eardrum.
© 2012 Lippincott Williams & Wilkins, Inc.