Otoscopy
Purpose of the Otoscopic Examination
Visual examination of the external auditory canal of the tympanic membrane assesses general health and pathological issues and provides information regarding potential concerns for conductive hearing loss. It is necessary to assess the ear canal prior to performing audiologic tests to determine the safety of performing such measures and to assist in interpretation of audiologic results. The audiologist must visualize the external ear canal and tympanic membrane to understand the physical influences that can impact the outcome of the outcome of the audiologic evaluation. It is necessary to determine that it is safe to perform audiolgic testing involving the placement of probe tips and earphones into the canal. The presence of foreign bodies or cerumen in the ear canal has the potential to impact immittance measures and to create a conductive hearing loss. Observation of the tympanic membrane allows the clinician to have insight, prior to testing, regarding pathology or structural differences that may impact test results.
Materials
Otoscope; a handheld device with magnification and light which allows the clinician to visualize internal anatomy. Ensure that the power to the light of the otoscope is sufficient, that it is properly disinfected and that a fresh supply of speculums are available for examination.
Performing Otoscopy, Procedures & Instruction
An otoscopic examination typically is performed using a handheld otoscope. The otoscope has a light source that must be turned on prior to use. The otoscope contains lenses, which magnify the image of the ear canal. A speculum is placed on the end of the otoscope and is placed into the ear canal. The audiologist can visualize the components of the ear canal and tympanic membrane by looking through the viewing window of the otoscope.
To perform otoscopy, the otoscope is held in one hand, near the "head" of the otoscope. Using the other hand, the pinna is gently pulled up and toward the back of the patient's head to straighten out the normally "S-shaped" ear canal and allow for visualization of the tympanic membrane. The tip of the speculum of the otoscope is gently advanced into the external ear canal. Importantly, the fingers of the hand holding the otoscope are placed against the head of the patient. By doing this, the otoscope will be unable to move independently of the patient's head. This is important, so that if the patient moves during examination, the otoscope tip will not cause damage to the patient's ear canal. The patient should be instructed to remain still during the otoscopic examination to allow for visualization and to prevent injury to the ear canal.
Ask the patient permission to look inside of their ear canals and explain that you would like to visually inspect their ear. Place a fresh speculum on the tip of the otoscope, turn the light on and verify proper luminous intensity. With the otoscope in one hand, take the freehand and pull the auricle superiorly and posteriorly to straighten the s-shaped canal, brace in case of patient movement and insert the speculum, adjusting as necessary to visualize the tympanic membrane.
To perform otoscopy, the otoscope is held in one hand, near the "head" of the otoscope. Using the other hand, the pinna is gently pulled up and toward the back of the patient's head to straighten out the normally "S-shaped" ear canal and allow for visualization of the tympanic membrane. The tip of the speculum of the otoscope is gently advanced into the external ear canal. Importantly, the fingers of the hand holding the otoscope are placed against the head of the patient. By doing this, the otoscope will be unable to move independently of the patient's head. This is important, so that if the patient moves during examination, the otoscope tip will not cause damage to the patient's ear canal. The patient should be instructed to remain still during the otoscopic examination to allow for visualization and to prevent injury to the ear canal.
Ask the patient permission to look inside of their ear canals and explain that you would like to visually inspect their ear. Place a fresh speculum on the tip of the otoscope, turn the light on and verify proper luminous intensity. With the otoscope in one hand, take the freehand and pull the auricle superiorly and posteriorly to straighten the s-shaped canal, brace in case of patient movement and insert the speculum, adjusting as necessary to visualize the tympanic membrane.
Interpretation/SOL
Assess the anatomy and general health of the auditory canal and take note of any abnormalities.
Landmarks
|
In the case of a normal ear canal and tympanic membrane, there are a number of landmarks to be visualized.
The "light reflex" or "cone of light" is a reflection of the light source used for otoscopy that appears in the inferior anterior quadrant of the normal tympanic membrane. The cone of light can be used as a landmark to orient the viewer. The presence of the cone of light also is an indication of a normally shaped, concave tympanic membrane; that is, the tympanic membrane is neither bulging as is in the case of otitis media, nor retracted. The annulus, the ring of cartilage surrounding the tympanic membrane, also may be visualized. At the top of the tympanic membrane, an area of reduced tension, known as the pars flaccida may be seen. The normal tympanic membrane has a concave shape. This is due to the attachment of the middle of the tympanic membrane to the manubrium of the malleus, known as the umbo. Depending on the thickness of the tympanic membrane, some other structures of the middle ear space may be visualized, including the long process of the incus, and/or the stapedial tendon. |
Oxford Medical Education
|
Management
Collapsed Ear CanalThe ear canal itself must be observed prior to testing. In some patients, the cartilage of the ear canal is quite pliable. The use of supra-aural earphones in such a case can actually collapse the ear canal, resulting in a conductive hearing loss due to attenuation of sound. This phenomenon generally can be remedied by the use of insert earphones to obtain a valid hearing assessment.
|
|
CerumenThe presence of cerumen in an ear canal is a normal and healthy phenomenon. Cerumen varies in appearance, depending on it's consistency. Cerumen most often is a yellowish or brownish color, and may appear to be hard or soft. Typically, the presence of excessive cerumen creates a high-frequency hearing loss. When cerumen completely occludes the ear canal, a flat conductive hearing loss may be found. In cases where cerumen has the potential to influence audiologic outcomes, it should be removed prior to initiation of testing.
|
|
Foreign BodiesAny variety of foreign bodies may be present in the ear canal including cotton swabs or tissue, insects, pieces of hearing aids such as wax traps or open-ear domes, or any other objects that fit inside the ear canal.
|
|
ExosostosisExostoses are bony growths in the ear canal. In most cases, these growths are harmless. Location and size must be noted to determine whether there is potential for interference with earphone placement and, therefore, with audiometric outcomes.
|
|
TympanosclerosisCalcifications may occur on the tympanic membrane as a result of inflammation of the membrane. This condition, known as tympanosclerosis, results in white, generally horseshoe-shaped marks on the tympanic membrane
|
|
PerforationA perforation of the tympanic membrane may allow visualization of the middle ear structures. In some cases, a very thin layer of tympanic membrane may form following previous perforation. This neomembrane often is mistaken for a current perforation.
|
|
Pressure Equalization TubesPressure equalization tubes are surgically placed in the tympanic membrane in cases of eustachian tube dysfunction. If the tube is in place, it is important to note whether the tube appears patent or if wax or other debris appears to be blocking the opening of the tube. In some cases, the tube may be partially extruded from the tympanic membrane, may be found in the ear canal, or, very rarely, may be visualized in the middle ear space.
|
|
Otitis MediaIn the case of otitis media, various anomalies of the tympanic membrane can be seen. When excessive fluid is present in the middle ear space, a bulging tympanic membrane may be observed. In other phases of otitis media, air bubbles or a fluid line may be observed through the tympanic membrane. In some cases, the tympanic membrane may appear to be retracted against the handle of the malleus or other structures of the middle ear space.
|
|
External OtitisExternal otitis is an inflammation of the external ear canal. Other external ear canal conditions can be visualized during otoscopy, such as growth of fungus.
|
|
CholesteatomaCholesteatoma is an abnormal skin growth in the middle ear, behind the eardrum. These develop as cysts or pouches that fill with old skin cells and other waste material. Typically, a cholesteatoma occurs because of Eustachian tube dysfunction, as well as infection in the middle ear, and can lead to deafness.
|
|
When to refer
Otoscopic examination of the ear canal may reveal situations or conditions that require referral to a medical physician for treatment. Such conditions include but are not limited to, bleeding or discharge from the ear, evidence of infection in the middle ear space or ear canal, evidence of fluid in the middle ear space, perforation of the tympanic membrane, presence of foreign objects in the ear canal, visible ear canal obstruction or abnormalities, and cerumen that is deep in the ear canal or of a consistency that cannot be removed without risk of damage to the ear canal.
Works Cited
Gelfand, Stanley A. Essentials of Audiology. Thieme, 2016.
DeRuiter, Mark, and Virginia Ramachandran. Basic Audiometry Learning Manual. Plural Publishing Inc., 2017.
Images: Oxford Medical Education
DeRuiter, Mark, and Virginia Ramachandran. Basic Audiometry Learning Manual. Plural Publishing Inc., 2017.
Images: Oxford Medical Education