Tuning Forks

The 512-Hz tuning fork is the most accepted frequency for assessing hearing using the Weber and Rinne tests. The Weber test consists of placing the stem of a vibrating fork on the center of the patient's forehead, crown, or nasal bridge. Sound is transmitted equally into each cochlea by bone conduction. While the fork is vibrating, ask the patient in which ear the sound is louder. A patient with a one-sided sensorineural loss will hear the fork louder in the opposite, normal ear. A patient with...

Mycotic Otitis Externa

This disorder is also known as fungal otitis externa or chronic diffuse otitis externa. It differs from the previously mentioned infections in that it is not quite so painful, but more indolent, yet persistent. The usual complaints are of blockage, thick drainage, dull pain, and itching. These infections occur more often than most clinicians expect, and they are often treated inappropriately with antibiotic drops. The most notable finding on ear examination is the presence of matter thick moist...

Malignant Otitis Externa

Malignant otitis externa is also known as necrotizing otitis externa or skull base osteomyelitis in its full-blown form. Obviously, the second name is the gentlest one, but the other two imply its ominous characteristics. This type of infection is typically seen in elderly diabetics or immunocompromised patients. It can spread from the external canal to cause osteomyelitis in the temporal bone with potentially fatal complications. Characterisically, the patient presents with an external earache...

Pure Tone Audiometry

Audiometry is the precise method of hearing assessment. It is performed in a soundproof compartment by an audiologist, who uses an audiometer to introduce measured sound intensities of selected tones to the listener, usually through earphones. Pure tone thresholds are the minimal intensities of given tones (frequencies) that can be heard by the person being tested. These thresholds are usually recorded on a grid, like the one shown in Figure 1.1, to create an audiogram. This one has no...

Overview of Mastoiditis

Having discussed a number of forms of mastoiditis, some clarification is in order at the end of this chapter. This diagnosis was ominous in the old days before antibiotics. It often led to primitive surgery, deafness, brain complications, and sometimes death. Times have changed. Now there are fewer acute cases and more refined treatments. As a review, some definitions and explanations are presented here. 1. Acute mastoiditis or acute coalescent mastoiditis refers to the purulent type that may...

Ear Effusions in the Young Special Considerations

Tympanogramm

Infants and toddlers are afflicted most often with middle ear effusions, and they are not about to tell us they have conductive hearing loss or autoph-ony. If their ears hurt, they will cry and fuss, especially when recumbent at night. Certainly, pain is present with acute or smoldering infection. However, many little ones have ongoing thick sterile effusions and offer very few complaints. Their mothers may or may not suspect a hearing loss. We have little history to go on. Physical diagnosis...

The External Auditory Canal

The external auditory canal (EAC) consists of a cartilaginous outer one-third and a bony inner two-thirds. Figure 3.2 shows its relationship with deeper structures. The entire length of the canal is a little over 3 cm from the external meatus to the TM. From the outside in, the outer third is directed slightly posteriorly, whereas the inner two-thirds is directed anteroinferiorly and has an anterior bony hump that occludes a view of the very front portion of the TM. Because of this curvature,...

Adhesive Otitis Media

Retraction pockets that are posterior and superior are potentially dangerous. These are the ones located over the junction of the incus with the stapes at the entrance to the mastoid antrum, or more superiorly in the pars flaccida. The problem is that they tend to adhere to the ossicles and invaginate inward toward the mastoid antrum or attic (epitympanum) as time goes on. This leads to complications. These pockets tend to occur in individuals with long-standing eusta-chian tube blockage...

Contents

1 Hearing and Basic Audiometric Concepts 1 Conductive vs. Sensorineural Hearing Loss 4 2 Equipment and Ear Examination Methods 7 3 Useful Anatomy and Function 13 4 Disorders of the External Ear 26 Temporomandibular Joint Syndrome 26 Neuralgias Involving the Ear 29 Congenital Disorders of the External Ear 33 Noncongenital Cysts and Keloids of the Auricle 35 Skin Disorders of the External Meatus 36 Other Chronic External Ear Disorders 43 Cerumen Accumulations and Keratoses 44 Tumors of the...

Acute Diffuse Otitis Externa

This condition, a well-known painful infection of the canal, is otherwise known as swimmer's ear. Water immersion is not always the cause, but the disease occurs most often in warm, humid conditions. Moisture in the ear, even from perspiration, plays a causative role. Local trauma to the canal is also a precipitating factor. Abrading a wet, macerated canal with a cotton swab to clean it or scratch an itch is often the initiating insult, implanting bacteria under the epithelium. The darkness of...

Acute Mastoiditis

Mastoiditis

Now let us assume we have a severe acute infection and no antibiotic treatment. This scenario is extremely rare these days. The suppuration in the middle ear and adjacent mastoid cavity may continue. There is usually Fig. 5.4 Mastoiditis with subperiosteal abscess. (Source Hughes GB, Pensak MP. Clinical Otology. New York Thieme 1997) little pain because the middle ear continues to decompress through the draining perforation. Two or three weeks may elapse before the fourth stage of mastoiditis...

Eczematoid Dermatitis

Eczema of the meatus and surrounding structures may affect any age group. It may be familial atopic dermatitis, acquired-irritant, or allergic eczema. The lesions usually start as small blisters, which itch intensely and are scratched away, leaving skin that becomes lichenified with exaggerated striations and scales. Weeping of sticky clear fluid is often present. Allergy to topical irritants, such as fabrics, soap, hair coloring, or hair spray, as well as other environmental allergens, may be...

The Tympanic Membrane and its Landmarks

Scar Tympanic Membrane

This is the most important structure for the clinician diagnostically, because its appearance, and what can be seen through it, are by and large the only anatomic clues to what goes on inside (Figs. 3.3 and 3.4). The most visible landmark beneath the TM is the manubrium, or handle, of the malleus, the lower portion of this first ossicle. The upper portion of the manubrium has a visible prominence, seen near the top of the TM, called the short process. The...

Congenital and Hereditary Disorders

Sensorineural hearing losses present at birth are congenital disorders. Some, but not all, of them, are hereditary, i.e., genetic, and the others are complications of pregnancy. Most are due to cochlear defects. There may be destruction of the vascular and membranous regions supporting the organ of Corti Scheibe deformity or loss of the neural elements, from the hair cells inward toward cranial nerve VIII Mondini deformity . It is important to discover congenital hearing loss as early as...

Scarring and Tympanosclerosis

Tympanosclerotic Plaques

A normal TM is often described as pearly in appearance. In fact, it is almost transparent. Scarring, which occurs in the middle fibrous layer, destroys this lucency. Scarring may result from repeated effusions or Fig. 5.3 Peripheral tympanosclerosis with central neomembrane, left ear. Source Sanna M, Russo A, DeDonato G. Color Atlas of Otoscopy. Stuttgart Thieme 1999 Fig. 5.3 Peripheral tympanosclerosis with central neomembrane, left ear. Source Sanna M, Russo A, DeDonato G. Color Atlas of...

Noise Induced Hearing Loss

Noise Damage Audiogram

How much of the hearing loss of aging is due to noise exposure Actually, this is a difficult question that often arises in litigation, when an aging patient is seeking compensation for his hearing loss from years of industrial noise exposure. Quite certainly, the two types of loss coexist in many individuals and one aggravates the other. However, characteristic audio-metric differences are noted in the pure forms. The early loss from noise damage shows up as a dip at 4 KHz most often, with...

The Eustachian Tube

The eustachian tube ensures that air pressure inside the drum is equalized with atmospheric pressure lateral to the drum. Unfortunately, in combination with the cumbersome middle ear and related structures, it is the source of many problems. If we were fish, we would need only an external membrane over an inner ear. Evolution of life in the earth's atmosphere has mandated the development of the drum, the ossicles, and a mucosa-lined middle ear cavity. Thus, the eustachian tube exists an...

Frostbite of the Auricle

This type of damage from prolonged exposure to cold is likely to affect the ear first. The auricle is quite vulnerable due to its exposed location, superficial blood supply near the skin's surface, and lack of sensitivity. At first, the involved skin is pale and numb. As warming occurs, the affected areas become hyperemic and painful and may even blister. Treatment should be with gradual warming in a cool room. Direct heat, massage, or snow application is not recommended, as it will simply...

Hematoma of the Auricle

This problem occurs most often in young athletes, particularly wrestlers or football players who practice without their headgear. However, any severe blunt trauma to the auricle can cause a hematoma at any age. The vascular anastamoses of the auricle make subperichondrial accumulation of blood, with recurrences and lack of reabsorption, a likelihood. Usually, the hematoma occurs on the superolateral surface, centered over the scapha and upper concha Fig. 4.1 . If left untreated, fibrosis and...

Skin Disorders of the External Meatus

The three major dermatoses of the external ear are seborrheic dermatitis, eczema, and psoriasis. They have some overlapping characteristics and often affect the same areas, namely, the external canal, its meatus, and the concha. Sometimes adjacent regions, such as the lobule and postauricular areas, are affected. They seldom extend deeper than the outer one-third of the canal. Dermatologists refer to all three as the papulosquamous disorders. Patients afflicted with these disorders complain of...

Conductive vs Sensorineural Hearing Loss

There are two major categories of hearing loss that are key concepts for the clinician to understand. The first, conductive hearing loss, is due to an outer or middle ear problem a problem conducting sound waves through the ear canal to the eardrum and then through the middle ear apparatus toward the inner ear. Causes of conductive loss might include obstruction of the ear canal by cerumen wax , impairment of middle ear function by fluid, or fixation of the middle ear ossicles by disease. With...

Seborrheic Dermatitis

This is the most prevalent of the three dermatoses affecting the external ear. It presents as a diffuse scaliness, with a pink or orange discoloration of the skin, in and around the external meatus. Often the involved skin is greasy, but other times it is simply dry and flaky. The lesion may be seen behind the auricle as well, along with other locations on the face, especially on the forehead between the eyes and lateral to the nose. It occurs more often in the older adult population. Dandruff...

Perichondritis of the Auricle

Congenital Anomalies External Ear

This devastating infection occurs most often as a result of trauma, with penetration of the skin and a contaminated wound. Another possible cause is iatrogenic injury, i.e., ear surgery. The auricle becomes hot, red, swollen, and tender after the contaminating injury Fig. 4.2 . When perichondritis is suspected, aggressive treatment is necessary. The organism is usually Pseudomonas aeruginosa, although Staphylococcus aureus may be involved. If there is evidence of fluctuance from pus, drainage...

Nonorganic Hearing Loss

Occasionally patients will present with a complaint of hearing loss though, in fact, there is no loss. These individuals fall into two broad categories those who consciously fake a loss malingerers and those who have psychological disturbances, usually of the hysterical type. The malingerers are often seeking compensation for some sort of injury, or have some other agenda whereby they will gain from their loss, such as a disability determination. The individuals with hysterical loss tend to be...