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SECTION XIV Ear, Nose, and Throat Problems

to speak more clearly or louder. Speech reading (interpreting what is being said by extrapolating from the words heard and the facial expressions) may also help and is facilitated by good lighting. Clear enunciation , not merely elevated volume of speech, along with directly facing the presbycusic patient while engaged in conversation and deliberately slowing the rate of speaking optimizes verbal communication. Cessation of ototoxic drugs and treatment of otitis media (see Chapter 218) should not be overlooked. Patients exposed to occupational or recreational noise should be advised to use ear protection when in a noisy environment and to avoid further exposure. Cerumen removal should not be overlooked and may be accomplished by gentle body temperature water irrigation using a syringe or an irrigation jet. Removal of wax, as well as some foreign bodies, may be performed using a cerumen spoon or forceps under direct visualization provided by headlight and speculum. Insects are better exterminated first by instilla tion of mineral oil into the canal before removal is attempted. Patients with a history of tympanic membrane perforation or prior ear surgery (i.e., mastoidectomy) should be considered for otolaryngologic referral for cerumenectomy. Hearing Aids The use of a properly prescribed hearing aid can improve qual ity of life and daily functioning for those with hearing loss. When prescribed early in the course of hearing loss, decline in central sound processing and overall cognitive function is minimized, and social independence is preserved. A wide vari ety of hearing aids are available. Patients with sensorineural hearing losses—especially those with a flat threshold and good speech discrimination scores—benefit from amplification and deserve as much consideration as those patients with conductive hearing losses. Even those patients with steeply sloping, high frequency sensorineural hearing loss with poor discrimination may find amplification useful. An adequate trial following care ful otolaryngologic evaluation and competent fitting allows the patient to make an informed and personal decision regarding the helpfulness of amplification. The advent of digital hearing aids has lowered the threshold for prescribing hearing aids. With digital aids, substantially higher fidelity can be obtained, especially in difficult-to-amplify patterns of hearing loss, result ing in dramatic improvements in verbal communication. How ever, cost can become an issue. In the United States, hearing aids remain prohibitively expensive, greatly limiting access. Part of the reason for the high cost—exceeding five times the cost of the components—is the requirement for sale by prescription only. This requirement limits market size and derives from concern that hearing aid use without a formal otolaryngologic evaluation might mask a serious underlying cause. Proposals for lowering cost include eliminating the prescription requirement (which would enlarge market size) and improving insurance for better coverage of hearing aids and hearing evaluation services.

Laboratory Studies An audiogram is an essential component of the evaluation of the patient with hearing loss. The pattern of threshold loss has considerable diagnostic and therapeutic importance, helping to establish the type of hearing loss and to localize the site of lesion. Interpretation usually requires the joint efforts of an otolaryn gologist and an audiologist, but a few common patterns are use ful for the primary physician to recognize (see Appendix 212-1). Expensive imaging technology should be used sparingly but can be helpful in carefully selected patients. High-resolution com puted tomography of the temporal bone is used in the evaluation of certain middle ear and mastoid disorders, such as chronic infec tion and glomus tumors. Magnetic resonance imaging , particularly with gadolinium enhancement, has assumed a preeminent role in the evaluation of the patient with suspected retrocochlear disease (e.g., acoustic neuroma or multiple sclerosis). This is the test of choice when evaluating asymmetric sensorineural hearing loss. Auditory brainstem response testing has also been found use ful in the site-of-lesion testing, as has electronystagmography (see Chapter 166). Both tests require expert performance and interpretation and should be ordered only in consultation with consultants experienced in their use and interpretation. Otoacoustic emissions , particularly those evoked by sound stimuli, are used to test the integrity of the outer hair cells of the cochlea, from which they are believed to emanate. Otoacoustic emissions show promise as a screening test for assessing audi tory function in infants and other difficult-to-test patients. Screening for Hearing Loss An important aspect of geriatric care is assessment for hearing loss, given the adverse effect it can have on social and cognitive func tion, quality of life, and dementia risk. Support for such screening also derives from availability of effective means of detecting and correcting hearing loss and ability to screen adequately in the primary care setting. Nonetheless, the U.S. Preventive Services Task Force found existing evidence regarding benefits and harms of screening for hearing loss in asymptomatic persons over the age of 50 years insufficient to make a definitive recommendation but did endorse workup for persons who are symptomatic. The best screening methods and the optimal screening interval are the subjects of ongoing study. The American Acad emy of Otolaryngology-Head and Neck Surgery has developed a simple one-page “test” that the individual patient can self administer to see if a hearing evaluation by an otolaryngologist is warranted. Screening for Hearing Loss Gene Mutations Screening for hearing loss gene mutations is technically feasible because of the frequency of mutations in GJB2 and the ease with which these can be detected (gene size is small). However, the meaning of the findings is unclear, making proper use of the information problematic. Further study is needed, and the reader should watch the literature closely because this is a rapidly evolv ing aspect of hearing loss research. Adult hearing loss patients with a family history of inherited hearing loss should also be counseled on the potential need for hearing screening of their children.

Prevention of Hearing Loss—Patient Education

SYMPTOMATIC MANAGEMENT AND PREVENTION (1,3–6,8,9,12,16–24) Simple Measures to Improve Impaired Hearing Prevention centers on limiting noise exposure . As noted, noise damages sensory hair cells through direct physical injury as well as by formation of reactive oxygen species and calcium overload. Short-term exposure to very loud noise, such as attendance at a rock concert, can result in temporary muffling of hearing acu ity, ear fullness, and tinnitus (so-called temporary threshold shift ), which usually resolves within a week or two. More sustained or more prolonged exposure can lead to death of sensory hair cells followed by loss of spiral ganglia and permanent hearing loss (i.e., permanent threshold shift ). Consequently, the use of ear plugs, noise-cancelling head phones, avoidance of venues with excessively loud noise, and keeping the volume reduced when Copyright © 2020 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. The primary physician’s role in the treatment of hearing loss is relatively limited, but simple advice and support are much appreciated. Elders report that cupping the hand behind the ear can be of help both in actual hearing and alerting others