Marsena Collins, ARNP, ENP
Knowing how to perform a thorough ear examination is a vital skill for Advanced Practice Providers (APP). Pathology seen in an ear examination can range from benign (cerumen impactions, otitis media), to rare and potentially life-threatening. These findings can include acute bacterial mastoiditis, Ramsey-Hunt syndrome, and others. Therefore, a thorough ear examination is key to diagnosis. A practical understanding of the anatomy of the ear, a suitable choice of otoscope and speculum, and a reliable examination technique are all vital parts of this important exam.
Step 1 of a Thorough Ear Examination
Anatomy and Physiology
First, you need to understand the anatomy of the external, middle, and inner ear systems. This also helps clinicians to interpret between what may be actual, vague, or even misleading symptoms. The proximity of the ear to the brain should also be appreciated. Likewise, the interaction of the ear to the brain, skull-base, and cranial nerves must also be appreciated. In general, abnormalities of the external and middle ears will produce conductive hearing loss, and inner ear abnormalities will produce sensorineural hearing loss.
External Ear
The external ear includes the auricle (pinna), the external auditory meatus and canal, and the external (lateral) layer of the tympanic membrane. The external ear’s function is the funneling of acoustic waves to the tympanic membrane and, therefore, the middle ear. The entire external ear can be visualized during an examination.
Middle Ear
The middle ear is an air-filled cavity within the temporal bone of the skull. It contains three ossicles, the internal (medial) layer of the tympanic membrane, and also the eustachian tube orifice. It is lined with the same respiratory epithelium that lines the eustachian tube and the upper aerodigestive tract. There are three ossicles (lateral to medial) named the malleus, incus, and stapes. These three small bones vibrate together with sound frequency. Therefore, the primary function of the middle ear is to transmit acoustic waves from the tympanic membrane of the external ear to the oval window of the inner ear through the ossicles. During the examination, structures of the middle ear can be viewed through the tympanic membrane. These include the lateral process of the malleus, the incudostapedial junction, and occasionally the promontory.
Inner Ear
The inner ear contains the vestibular system and cochlea, both of which have a bony and membranous portion. Likewise the main function of the inner ear is to convert acoustic vibrations into neural impulses for hearing. It also detects and transmits cranial movement for balance. Some parts of the inner ear may not be visible. However, signs of inner ear disease – such as sensorineural hearing loss or vestibular dysfunction – can be elicited.
Step 2 of a Thorough Ear Examination
Choice of Otoscope
An otoscope allows for visualization of the pinna, external auditory canal, and also the tympanic membrane. The light also enables the examiner to perform a close examination of the pre- and postauricular areas. The otoscope should be fully charged. An undercharged otoscope will produce poor light and impart an artificial yellow tinge onto the tympanic membrane. Likewise, a dim scope light may potentially lead to the misdiagnosis of straw-colored middle ear fluid. Pneumatic otoscopy tests the mobility of the tympanic membrane. Poor mobility of the tympanic membrane is the most reliable test for otitis media. This requires an otoscope with a pneumatic bulb (essential for reliable exam) and speculum with rubber rings to create an air-tight seal within the canal.
Choice of Speculum
Use the largest speculum that comfortably fits within the external auditory canal. This permits optimal visualization and illumination. The average adult external auditory meatus is about 7 mm in diameter. Therefore, you should choose a speculum closest to the size of the patient’s size. A large speculum also allows the entire tympanic membrane to be seen from a single position of the otoscope. This is more comfortable for the patient because pressure is evenly spread around the entire circumference of the ear canal.
In contrast, a smaller speculum transmits force on only one point of the ear canal and is uncomfortable. Otoscopy through an inappropriately small speculum requires a separate examination of each quadrant of the tympanic membrane in order to generate a composite image of the entire structure. This also requires constant re-positioning of the speculum within the ear canal. In adults, a 5 mm inner diameter speculum is appropriate. Children have narrower canals and therefore a speculum with an inner diameter of 4 mm is generally suitable. You should use a 2.5–3.0 mm inner diameter speculum in babies.
Step 3 of a Thorough Ear Examination
Examination Technique/Otoscopy
The patient should be sitting upright and facing the examiner. The first step of the exam is to visualize the ears. Always examine both ears. However if the disease is unilateral it is advisable to examine the normal “better” ear first. You can see differences in anatomy with a good external exam. This exam also avoids the possibility of cross infection. The examiner may also need to clear excessive cerumen and foreign material from the outer canal to visualize the entire canal & tympanic membrane prior to thorough examination.
Below is a systematic examination of the outer ear prior to otoscopic exam and things to NOTE!!
Inspect the auricle/post auricular skin
- Tenderness
- Obvious abnormalities
- Discharge, surgical or traumatic scars, masses, evidence of pits or sinuses, or skin changes such as erythema or desquamation
Inspect the pinna
- Look for congenital malformations
- Scars, erythema, edema, masses
- Exudate from the external auditory canal
Examine the mastoid
- Erythema
- Swelling
- Loss of the post-auricular sulcus
- Anteroinferior displacement
Otoscopy
Hold the otoscope with the hand that matches the same side of the patient. For example, use your right hand to examine the patient’s right ear. Likewise, the left ear should be examined with your left hand.
You should also hold the otoscope in one of two ways:
Pencil Grip Technique: Hold the otoscope like a pencil between the thumb and the index finger with the ring and little fingers resting against the patient’s temple.
Pistol Grip Technique: Grip the otoscope in the palm of the hand and the dorsal aspect of the index finger rests against the patient’s cheek.
Use of either technique also ensures that the examiner’s hand rests against the side of the patient’s face. This means that if the patient moves, the otoscope will also move in unison.
Either technique ensures stability of the physician’s view along the ear canal and the patient’s comfort during the examination. Straighten the external ear canal before inserting the speculum. Using the free hand to gently lift the pinna upward and backward allows for better visualization.
Children
You should pull the pinna straight back in a horizontal direction. This allows for alignment of the ear canal. It is important to keep the canal straight throughout the examination as this keeps the tympanic membrane in view. Inspect the external meatus before you introduce the speculum. Likewise, the speculum should be carefully introduced into the canal. Children are often easiest to examine while seated on their parent’s lap. The parent can help by restraining the child with one hand placed firmly on the forehead and holding the side of the child’s head against their chest. The parent’s other arm should hold the child’s arms and body to prevent moving and grabbing the speculum.
Things to Note
In adults, the pinna should be pulled posteriorly and superiorly. This straightens the external auditory canal and aligns the canal’s cartilaginous and bony portions. Again, gently insert the otoscope into the auditory canal. You should note any discomfort. Document all otoscopic findings. Ear problems represent a majority of chief complaints evaluated daily in urgent, primary, or emergency care settings. Diagnosis is usually based off history and clinical examination alone.
A systematic approach is key to performing a through ear examination to establish an accurate diagnosis and treatment plan. I truly hope this above outline serves as a guide to proper ear examination.
References
Hogan CJ, Tadi P. Ear Examination. [Updated 2021 Jan 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK556014/
Hawke M, Keene M, Alberti PW. Clinical otoscopy: an introduction to ear diseases, 2nd ed. London: Churchill Livingstone, 1990.
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