Postgraduate Medicine

ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20

Medical management of hearing loss William L. Meyerhoff To cite this article: William L. Meyerhoff (1977) Medical management of hearing loss, Postgraduate Medicine, 62:4, 103-112, DOI: 10.1080/00325481.1977.11714641 To link to this article: https://doi.org/10.1080/00325481.1977.11714641

Published online: 07 Jul 2016.

Submit your article to this journal

View related articles

Citing articles: 1 View citing articles

Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20

• Hearing Joss, much like facial paralysis, headache, and visual disturbance, is mere! y a symptom. It may occur alone, as part of a generalized disease process, or as one manifestation of a syndrome. lt may represent a peripheral or central nervous system phenomenon. As with any symptom complex, treatment of hearing Joss is based on the underlying pathophysiology. Without knowledge of the various maladies which may result in hearing Joss, a proper patient evaluation cannot be made, and without proper evaluation, the diagnosis will often be overlooked. Specifie diagnosis should be sought in all cases. Although in many cases definitive treatment may not be possible, the physician's responsibilities entail prevention of progression where possible, recognition of associated disorders, compensation for irremediable loss (eg, hearing aid) when appropriate, epidemiologie study, genetic and psychosocial counseling, and habilitation or rehabilitation. The classification of hearing loss as conductive, sensorineural, or mixed is usually determined by his tory, physical examination, pneumatic otoscopy, and tuning-fork test and confirmed audiometrically. The loss may be congenital or delayed, genetic or nongenetic, and progressive or stable. A detailed history is of paramount importance, with special reference to the prenatal and postnatal periods, family history, age at onset ofhearing Joss, and known possible causes. History taking should be followed by careful examination of the head, neck, integument, eyes, and musculoskeletal, cardiovascular, genitourinary, and nervous systems. Physicians are all too often content merely to differentiate conductive from sensorineural hearing Joss and too easily placated by diagnoses such as presbycusis or idiopathie sensorineural hearing Joss without appreciating the implications. As knowledge increases, the number of such diagnoses will decrease.

medical management of hearing loss William L. Meyerhoff, MD University of Minnesota Medical School Minneapolis

consider What are the three major types of hearing loss? What metabolic disturbances may result in sensorineural hearing loss? What treatment is recommended for sudden hearing loss when the cause cannot be determined?

Congenital Conductive and Mixed Hearing Loss Congenital hearing Joss of the conductive or mixed conductive and sensorineural types may occur alone or be associated with one of the many syndromes, both genetic and nongenetic, in which hearing Joss is a feature. Treatment is surgical when possible, with early auditory habilitation, attention to associ-

Vol. 62 • No. 4 • October 1977 • POSTGRADUATE MEDICINE

103

hearing loss: medical m a n a g e m e n t - - - - - - - - - - - - - - - - - - - - -

ated anomalies, genetic and psychosocial counseling, and epidemiologie study. Medical management alone is of no value in improving hearing in such cases. Rarely, however, in congenital hypothyroidism (cretinism), medical treatment may improve hearing.1 Syndromes in which conductive or mixed hearing Joss occurs are Iisted in table 1. 2

amenable to medical therapy. Auditory rehabilitation and psychosocial counseling are required. Otosclerosis-Incidence of clinical otosclerosis, a primary genetic disease of the Iabyrinthine capsule, is 0.5% to 1.0% in the US population. Although the condition may res pond to medical therapy, treatment is primarily surgical. Administration of sodium fluoride and calcium carbonate to aid maturation of the disease process has been recommended,5 especially in cochlear otosclerosis, where sensorineural hearing Joss coexists. Rheumatoid arthritis-Occasionally the genetic conductive and mixed hearing loss of rheumatoid arthritis improves with steroid therapy. Sorne have suggested th at the middle ear synovial joints are affected by the disease process, but others dispute this theory. 6 Otitis media-Aside from otitis media there are few nongenetic causes of conductive hearing Joss for which the treatment of choice is medical. Serous otitis media is an acquired sterile inflammation of the middle ear cleft with transudation of plasma-like material and in sorne cases associated secretions of glycoproteins and immunoglobulins. It often occurs secondary to eustachian tube dysfunction and presents with hearing loss. Treatment is aimed at reestablishment of middle ear ventilation by elimination of the underlying cause when possible or by topical and systemic therapy with decongestants, politzerization, autoinflation, and insertion of ventilating tubes. Acute infectious otitis media must be treated systemically with antimicrobials. Hearing Joss due to chronic otitis media usually is of the mixed type, involves medically irreversible disease, and requires surgical intervention. In luetic and tuberculous otitis media, adjunctive medical therapy is necessary.

Delayed Conductive and Mixed Hearing Loss

Congenital Sensorineural Hearlng Loss

Genetic and nongenetic conditions which result in delayed conductive and mixed hearing Joss are listed in table 2. Management is usually surgie al, although severa! entities (eg, otosclerosis and rheumatoid arthritis) are

Sensorineural hearing Joss is less weil understood than the conductive type. It may be genetic or nongenetic and may occur either as an isolated event or as part of a symptom complex. Causes are listed in table 3.

table 1. causes of congenital conductlve and mlxed hearlng loss2 Nongenetlc

Genetle Cause

Mode of inheritance

Manifestations

Cause

Treacher Collins syndrome

Dominant

External auditory canal atresia Middle ear anomalies Downward slanting eyes Lower lid coloboma Flat malar eminence Micrognathia

Viral infection (eg, rubella)

Apert

Dominant

Frontal bassing Exophthalmos Hypoplastic maxilla Syndactyly

Martan syndrome

Dominant

Pigeon breast Dolichocephaly Hammer toes

Pierre Robin syndrome

Dominant

Glossoptosis Micrognathia Cleft palate

Crouzon dlsease

Dominant

Premature fusion of cranial sutures Shallow orbits Exophthalmos Parrot nose Hypoplastic maxilla

Fanconl syndrome

Recessive

Abnormal or missing thumbs Mental retardation Pancytopenia Skeletal, heart, and renal malformations

MObius syndrome

Recessive

Facial diplegia Ophthalmoplegia External ear malformations Tongue paralysis Possible malformations of the extremities

syndrome

104

Ototoxic drugs (eg, thalidomide) Metabolic disorders (eg, hypothyroidism)

POSTORADUATE MEDICINE • October 1977 • Vol. 62 • No. 4

table 2. causes of delayed conductlve and mlxed hearing loss2 Genet le

Nongenetlc

Cause

Mode of inheritance

Manifestations

Presenting cause

Underlying cause

Otosclerosis

Dominant

Bone resorption and redeposltion Progressive bilateral involvement Onset in third or fourth decade

Serous otitis media

Rheumatold arthrltis

Variable

Multiple joint involvement wlth pain, inflammation, ana llmlted motion

Osteogenesls lmperfecta

Uncertain

Fragile bonas Large skull Blue sciera Triangular facies Hemorrhagic tendencies Stapes fixation

Paget disease

Dominant

Osteltis deformans with deformities of skull and long bonas Cranial neuropathies

Albers·Schonberg dlsaase

Allergy Regional infection (eg, sinus, nasopharynx) lmmunoglobulin deficiency Metabolic disturbance Previous Irradiation therapy Mechanical obstruction of eustachian tube orifice Interference wlth eustachian tube lymphatic drainage Neuromuscular abnormalitles (eg, cleft palate) Polyarterltls nodosa• Wegener gmnulomatosls* Eoslnophilic granulome• Neoplasm•

Recessive

Osteopetrosis with brittle sclerotic bon es Cranial neuropathies Large skull and mandible Bone marrow obliteration

Acute infectious otitis media

Allergy Bacterie

Chronic otitis media

Cholesteatoma Osteltis Structural abnormallty

Luetic otitis media

Syphilis

Tuberculous otltis media

Tuberculosis

Engelmann disease

Dominant

Diaphyseal dysplasia

Hurler syndrome

Recessive

Abnormal deposition of mucopolysaccharides Frontal bassing Stubby digits Mental retardation Hepatosplenomegaly

Virus

"Rare. a.•

Hearing Joss of this type rarely res ponds to medical or surgie al therapy, and acupuncture is of no value. Effort is directed toward habilitation, genetic and psychosocial counseling, epidemiologie study, and identification of associated anomalies. The genetic hearing Joss of Pendred syndrome coexists with nonendemic goiter in an otherwise normal child. Diagnosis is made by demonstrating the flush of nonorganified radioactive iodine from the patient's thyroid gland with thiocyanate. The thyroid gland may continue to enlarge with age, resulting in cosmetic deformity and airway obstruction. Coexisting carcinoma of the thyroid has been reported. 7

Delayed Sensorineural Hearing Loss Like congenital sensorineural hearing Joss, the delayed type may be genetic or nongenetic and with few exceptions is not amenable to

Vol. 62 • No. 4 • October 1977 • POSTGRADUATE MEDICINE

medical therapy. The socioeconomic considerations of this disability are immense, and rehabilitation, epidemiologie study, and genetic and psychosocial counseling are essential. Causes are listed in table 4. Sorne nongenetic factors are discussed briefly in the following paragraphs. Noise-induced hearing loss-This type of hearing Joss represents the most frequent cause for industrial compensation daims. It results from prolonged exposure to loud continuous noise or brief exposure to loud impulse noise. Guidelines for prevention are rigid, as there is no effective therapy. Head trauma-Hearing Joss resulting from head trauma, like th at resulting from noise, is irreversible. Sudden pressure change-A sudden change in either environmental or CSF pressure occasionally results in rupture of the oval or round window, with subsequent sen-

105

hearing loss: medical management - - - - - - - - - - - - - - - - - - - - - table 3. causes of congenital sensorlneural hearlng loss2 Nongenetlc

Genet le Cause

Mode of inheritance

Manifestations

Cause

Temporal bone deformities

Usually dominant

Michel total aplasia Partial aplasias of Mondini, Scheibe, and Alexander

Environmental factors

Pend red syndrome

Recessive

Coexistent nonendemic goiter Greatest hearing loss at high frequencies Unresponsive to thyroid hormone

Jervell and LangeNielsen syndrome

Recessive

Prolonged QT interval on ECG Profound sensorineural hearing loss Frequent syncope Possible sudden death

Waardenburg syndrome

Dominant

Lateral displacement of medial canthi White forelock Heterochromia of the irides Hypoplasia of the nasal alae

Usher syndrome

Recessive

Progressive retinitis pigmentosa

lntrauterine factors Infection Ototoxic drugs Metabolic disorders Irradiation Perinatal insults Erythroblastosis fetalis Trauma Anoxia Prematurity

sorineural hearing Joss. Patients may benefit from bed rest or from surgical intervention. 9 Metabolic disturbances-Metabolic disturbances occasion ally result in sensorineural hearing Joss. One fourth of hypothyroid patients have sensorineural hearing Joss which will improve with replacement thyroid therapy. The lesion site is unknown, but it appears to be cochlear. Occasionally associated is a conductive component due to middle ear alterations. 10 About 35% of patients with fluctuating hearing Joss show abnormal glucose tolerance, compared with 8% of a similar random population. This abnormality is a manifestation of hyperglycemia and delayed hyperinsulinemia without concomitant hyperproinsulinemia. When serum glucose leve! is altered experimentally. electrical changes are produced within the cochlea. The adrenopituitary axis pla ys an important role in glucose metabolism, and alterations in the homeostasis of this system have also been implicated in fluctuating hearing Joss. The significance of these findings is not clearly understood at present, and therapy does

106

not necessarily eliminate the hearing loss. 11 Hyperlipoproteinemia (especially types lia, lib, and IV) has been implicated in unilateral and bilateral sensorineural hearing Joss which is progressive, fluctuating, or sudden in onset. Reports of hearing Joss with abnormalities of types 1, III, and V have also appeared, 12 but su ch cases are unusual. Therapy consists main! y of dietary management, with reduction in intake of saturated fats and concentrated sweets. When this regimen is accompanied by weight Joss, lipid values often return to normal, followed by cessation of auditory symptoms. In refractory cases of type II, dextrothyroxine therapy might be considered. When triglyceride levels remain elevated, clofibrate might be of help. 12 Patients with chronic renal disease are subjected to a multitude of external factors (ototoxic diuretics and antibiotics, infection, immunosuppression) which make retrospective studies quite difficult. Sensorineural hearing Joss, however, has been recognized in these patients, and careful evaluation has identified chronic renal failure as a cause. 13 One case has been reported 14 of sensorineural hearing Joss secondary to hyperparathyroidism. The hearing Joss was probably related to neural compression from osteitis fibrosa cystica identified at the petrous apex. Bath the hearing Joss and the osteitis fibrosa cystica resolved with removal of a parathyroid adenoma. Taxie substances-Many substances are taxie to the inner ear. Heavy metals and sorne antibiotics have been associated with irreversible sensorineural hearing Joss, diuretics with bath reversible and irreversible Joss, and aspirin and cigarettes with reversible Joss. In typhoid fever and diphtheria, toxins form in the gastrointestinal and respiratory tract, respectively, which appear to affect the ear remotely.15 Space-occupying lesions-In any patient with unilateral sensorineural hearing Joss, a space-occupying lesion in the cerebellopontine angle should be suspected. Acoustic neuromas are the most corn mon type. Inflammatory disease-The inner ear is often the target of inflammatory disease. Viral and bacterial infections occasionally resuit in irreversible sensorineural hearing Joss.

POSTGRADUATE MEDICINE • October 1977 • Vol. 62 • No. 4

table 4. causes of delayed sensorineural hearing loss Genet le

Nongenetlc

Cause

Mode of inheritance

Manifestations

Cause

Progressive familial sensorineural hearing loss

Dominant, recessive, or X-linked

Early or late onset lsolated entity or part of syndrome

Noise

Alport syndrome

Dominant

Progressive hearing loss, becoming manifest by about Sudden pressure change age 10 years Glomerulonephritis Environmental Refractory to treatment CSF

Alstrèim syndrome

Recessive

Nystagmus and visual loss secondary to retinal degeneration at about age 1 year Progressive hearing loss just prior to adolescence Diabetes mellitus shortly alter adolescence

Refsum syndrome

Recessive

Onset in second decade Visual loss secondary to retinitis pigmentosa Ataxia Muscle wasting lchthyosis

Friedreich ataxia

Recessive

Nystagmus Optic atrophy Ataxia

von Recklinghausen disease

Dominant

Acoustic neuroma formation Ataxia Visualloss lnvolvement of cranial nerves V through X Cafe-au-lait spots

Primary amyloidosis' Dominant

Systemic amyloid infiltration

Head trauma Temporal bone fracture Labyrinthine concussion

Metabolic disturbances Hypothyroidism Abnormal glucose tolerance Adrenopituitary disorders Hyperlipoproteinemia Chronic renal disease Hyperparathyroidism Toxic substances Heavy metals (eg, lead, mercury) Antibiotics (eg, aminoglycosides) Diuretics (eg, ethacrynic acid, furosemide) Aspirin Cigarettes Toxins of typhoid lever and diphtheria Space-occupying lesions in cerebellopontine angle Acoustic neuromas Meningiomas Vascular anomalies Congenital cholesteatoma lnflammatory disease Viral infection (eg, measles, mumps, adenovirus type Ill, herpesvirus) Bacterial infection (meningococcal meningitis, suppurative labyrinthitis) Neurosyphilis Allergie inflammation Maniere disease

•Amyloid has not been identified in the eighth cranial nerve. 8

The fluctuating loss secondary to neurosyphilis frequently responds to penicillin and steroid therapy. Allergie inflammation is believed by many to cause both fluctuating and irreversible hearing loss. Sorne observers16·17 believe allergy to be the primary cause of Meniere disease. Meniere disease- This syndrome, characterized by aurai fullness, tinnitus, fluctuating hearing loss, and incapacitating episodie vertigo, may be idiopathie or secondary to alterations in metabolism, neurosyphilis, allergy,

Vol. 62 • No. 4 • October 1977 • POSTGRADUATE MEDICINE

trauma, or stenosis of the internai auditory canal. Medical treatment consists of avoidance of known allergens; administration of diuretics, vestibular depressants, and tranquilizers; and adherence to a low-salt diet. Specifie therapy should be directed to any identified cause. Surgieal decompression of the endolymphatic system has met with sorne success. It is difficult to assess the value of treatment because the course of Meniere disease is highly irregular and characterized by exacerbations and remissions. 18 ..,.

107

hearing loss: medical management--------------------table

s. causes of sudden hearing Joss Cerebellopontine angle neoplasms

Diabetes mellitus Arteriosclerosis

Syphilis

Hypertension

Blood dyscrasias Leukemia Pernicious anemia Hypercoagulable states

Hyperlipoproteinemia Allergie diatheses Viral agents Rubella Influenza Mycoplasma Herpes zoster Adenovirus type Ill lnfectious mononucleosis Rubeola

Multiple sclerosis Relapsing polychondritis Sarcoidosis Vascular abnormalities Cogan syndrome (nonsyphilitic keratitis and eighth nerva deafness)

Head trauma Bacterial agents Toxic agents

Sudden Hearing Loss Sudden loss of hearing, unilateral or bilateral, should be respected as a true emergency. The most common underlying disease processes, as weil as many presumed causes, are listed in table 5. Viral agents are presumed to cause hearing loss by one of four mechanisms. Viral infiltration of the ganglion or nerve, especially seen with herpes infection, results in neuronitis or ganglionitis. Invasion of the cochlear duct by the virus ofmumps, rubeola, rubella, or influenza causes endolymphatic labyrinthitis. Invasion of the perilymphatic space by a viral agent, especially herpes zoster, leads to perilymphatic labyrinthitis. Final! y, vascular occlusion associated with any viral infection may cause sudden hearing loss. When the cause of sudden hearing loss has been identified, therapy should be directed toward its eradication. When no cause is apparent, treatment should include hospitalization and bed rest; administration of heparin (1 0,000 units/day subcutaneously for one week) for its antiinflammatory, anticoagulant, and lipolytic properties; and administration of ACTH (40 units/day intramuscularly for one week) to decrease platelet adhesiveness and inflammation. Administration of a 10% solution of low-molecular-weight dextran (500 ml intravenously over four hours, repeated every 12 hours for one week) pre-

108

vents sludging of blood and rouleau formation. Histamine (2.75 mg in 250 ml of 5% dextrose and water intravenously over two hours, repeated every six hours for three days) helps achieve vasodilatation and increase cochlear blood flow. The hearing loss associated with blood dyscrasias, multiple sclerosis, relapsing polychondritis, sarcoidosis, vascular abnormalities, and Cogan syndrome may be either sudden or progressive and is usually irreversible. Steroid therapy may, however, improve the hearing loss associated with sarcoidosis and Cogan syndrome. Although reports differ, it is generally accepted that 25% to 30% of patients with sudden hearing loss have complete auditory recovery, 25% to 30% have partial recovery, and the remainder have no recovery. 9 Occasionally, when rupture of an inner ear fenestra is suspected, surgical intervention is indicated. The sooner therapy is begun, the better the prognosis.

Evaluation The evaluation procedure is detailed in the protocol. * A· thorough family history should be obtained for every patient with hearing loss, along with a history of any ototoxic drug use, otorrhea, head trauma, noise exposure, vertigo, gait disturbance, tinnitus, visual disturbance, otalgia, fullness, diplacusis, and recruitment. Age at onset, progression, fluctuation, and bilateralism or unilateralism of the hearing loss are also important factors in reaching a diagnosis. Information should be sought concerning precipitating events and signs and symptoms of hypothyroidism, multiple sclerosis, blood dyscrasias, arteriosclerosis, allergy, diabetes mellitus, congenital and acquired neurosyphilis, and renal disease. A complete head and neck examination is mandatory, with emphasis on visual inspection of the auricle, external auditory canal, and tympanic membrane. Tympanic membrane mobility is assessed with the aid of a pneumatic otoscope and tuning forks. Noise *Additional copies of the protocol used by Dr Meyerhoff for diagnosing the type and cause of deafness are available on request to the Editorial Department, POSTGRADUATE MEDICINE, 4530 W 77th St, Minneapolis, MN 55435.

POSTGRADUATE MEDICINE • October 19n • Vol. 62 • No. 4

diagnostic protocol for deafness His tory (Otolaryngologic and complete general) Physical examination (Otolaryngologic [head and neck] and complete general, including cranial nerve assessment) lnclude consultation for Funduscopic evaluation Neurologie evaluation, especially of the cranial nerves Medical evaluation for vascular, collagen, or other systemic disease Audiology (Frequent reevaluation will assess progression, improvement, or stability) Tuning fork tests: Rinne and Weber (other optional). Use Barany noise box when necessary. (These tests are to be done by a physician to corroborate audiologie findings) Whispered voice and shout test (using Barany masking) Pure tone air and bone Speech reception threshold Phonetic balance (discrimination) Modified tone decay test Loudness recruitment test (short increment sensitivity index [SI SI], alternate binaural loudness balance [ABLBJ, or both) Bekesy air conduction audiogram Binaural pitch matching Impedance measurements to include acoustic reflex Other tests as indicated, such as difference limen for frequency (DLF), temporal integration, competing messages, Stenger, evoked response Vestlbular evaluation Romberg sign, tandem standing Gait Spontaneous nystagmus (direction and type) Positional test Calorie test (3 ml ice water to compare gross symmetry, 30 ml ice water to prove a dead labyrinth) Electronystagmography, using air calorie testing method Radiologie evaluation Skull Ch est Mastoid and internai auditory meatus Polytomography of labyrinth and other parts of temporal bone as indicated Posterior tossa myelogram (clivogram) for suspected retrocochlear lesion Computed tomography Cardiac examination Vital signs (blood pressure, pulse, respiration, temperature) ECG Hematologie examlnation WBC count and differentiai Hemoglobin

Vol. 62 • No. 4 • October 1977 • POSTGRADUATE MEDICINE

Sedimentation rate Platelet count

109

diagnostic protocol - - - - - - - - - - - - - - - - - - Coagulation studles Prothrombin consumption Prothrombin time Partial thromboplastin time

Platelet count Definitive studies if either hypercoagulation or hypocoagulation is suspected

Renal evaluation Urinalysis

Creatinine

BUN

Endocrine evaluation Thiocyanate flush (Pendred syndrome) Fasting blood sugar ACTH plasma cortisol stimulation

Protein-bound iodine Cholesterol and triglycerides Glucose tolerance

Blochemlcal studles Total protein

Globulin

Albumin

Serum electrophoresis (Optional unless indicated by history or examination) Na, K, ca, Cl, co2 Llver functlon tests (Optional unless indicated by history or examination) Serologie and Immunologie evaluation VDRL FTA-ABS

Lupus erythematosus cell preparation Heteroagglutinin titer

Lumbar puncture Opening pressure Col or Cell count and differentiai Protein (total and electrophoresis) Electrolytes

Serologie studies Glucose Viral culture Culture for bacteria, fungi, and acid-fast bacilli

Viral studles (Contact local or state virology laboratory for specifie instructions regarding handling of specimens) Acute specimens (Should be obtained as early as possible within, but not after, 21 days of onset of deafness) Whole clotted blood (for culture and titer) Stool Washings from throat, nasopharynx, or both CSF Fluid from middle or inner ear, or both (Under special conditions, such as tympanotomy to evaluate a perforated round window, may be available for viral culture. Should be inoculated into tissue culture in operating room) Convalescent whole clotted blood (Should be obtained for culture and titer between third and fifth week after onset of deafness and at least 14 days after obtaining acute specimen of whole clotted blood) Handling of specimens Hand carry, preferably (Viral organisms are fragile and poorly withstand storage or mailing) Label viral specimens with "Special Study-Deafness," in addition to identifying data Exploratory tympanotomy (lndicated when spontaneous rupture of round window or other middle ear disease is suspected, or if perilymph is to be sampled for diagnostic purposes)

110

POSTGRADUATE MEDICINE • October 1977 • Vol. 62 • No. 4

hearing loss: medical management - - - - - - - - - - - - - - - - - - -

William L. Meyerhoff Dr Meyerhoff is associate professor of otolaryngology, University of Minnesota Medical School, and chairman, department of otolaryngology, Hennepin County Medical Center, Minneapolis.

threshold tests help quanti tate the hearing loss and establish the lesion site. Integrity of the cranial nerves should be assessed. In children special emphasis should be placed on the intrauterine and peripartum history and on intellectual and speech development. Careful examination of the integument and of the cardiovascular, genitourinary, ocular, musculoskeletal, and endocrine systems may help identify coexisting abnormalities. When the foregoing evaluation has been completed, the hearing loss should be confirmed audiologically with special site-oflesion tests, when applicable. At this point the diagnosis is usually evident, precluding the need for expensive and invasive laboratory and radiologie studies. If the diagnosis remains obscure, a complete blood cell count, urinalysis, thyroid studies, glucose tolerance test, clotting studies, lipid fractionation, FTA-ABS test,

and determination of serum electrolytes (particularly calcium and phosphorous) may help elucidate the underlying cause. Radiologie evaluation of the petrous apex and vestibular studies should be considered, especially in cases of unexplained unilateral sensorineural hearing loss. Young patients in whom a syndrome complex is suspected but not obvious should have further diagnostic studies: an ECG (for Jervell and Lange-Nielsen syndrome), thiocyanate flush (for Pendred syndrome), and creatinine clearance determination (for Alport syndrome).

Conclusion The socioeconomic impact of hearing loss dictates increased physician understanding of this malady. The feeling of futility must be abandoried and the diagnostic challenge met. An awareness of the underlying pathophysiology and of the multiple causative factors involved in hearing loss pro vides a solid foundation on which to base thorough evaluation, diagnosis, and successful management. • Address reprint requests to William L. Meyerhoff, MD, Box 396, Mayo Memorial Bldg, University of Minnesota Hospitals, Minneapolis, MN 55455. ReadySource on hearing Joss appears on page 143. CME Credit Quiz on hearing Joss begins on page 147.

References 1. Meyerhoff WL: Hearing Joss and thyroid disorders. Minn Med 57:897-898, 1974 2. Bergstrom L, Hemenway WG, Downs MA: A high risk registry to find congenital deafness. Otolaryngol Clin North Am 4(2):369-400, 1971 3. Paparella MM: The middle ear effusions. In Paparella MM, Shurnrick DA (Editors): Otolaryngology: Ear. Philadelphia, WB Saunders Co, 1973, vol2, pp 93-112 4. Ledderer FL, Meyerhoff WL: Granulomas and other specifie diseases of the ear and temporal bone. In Paparella MM, Shumrick DA (Editors): Otolaryngology: Ear. Ed 2. Philadelphia, WB Saunders Co, vol 2 (to be published) 5. Moore GR, Robbins JP, Seale DL, et al: Fluoride and clinical otosclerosis. Arch Otolaryngol 98:327-329, 1973 6. Lucente FE: Connective tissue disorders in otolaryngology. Ann Otol Rhinol Laryngol 83:314-322, 1974 7. Roberts KD: Thyroid carcinoma in childhood in Great Britain. Arch Dis Childhood 32:58-60, 1957 8. Konigsmark BW, Gorlin RJ: Genetic and Metabolic Deafness. Philadelphia, WB Saunders Co, 1976 9. Meyerhoff WL: Sudden deafness. Tex Med 72:80-83, 1976

112

JO. - - : The thyroid and audition. Laryngoscope 86:483489, 1976 Il. Kitabchi AE, Shea JJ: Diabetes mellitus in fluctuant hearing Joss. Otolaryngol Clin North Am 8(2):357-368, 1975 12. Spencer JT Jr: Hyperlipoproteinemias in the etiology of inner ear disease. Laryngoscope 83:639-678, 1973 13. Quick CA: Hearing Joss in patients with dialysis and renal transplants. Ann Otol Rhinol Laryngol 85:776-790, 1976 14. Page JR, Jash DK, Pate) JB: Vllth and Vlllth cranial nerve palsies due to parathyroid adenoma with associated osteitis fibrosa cystica. J Laryngol Otol 89:761-766, 1975 15. Quick CA: Chemical and drug effects on inner ear. In Paparella, Shumrick (Editors),3 pp 391-406 16. Marcus RE: Cochlear and neural diseases: Classification and oto-audiologic correlations. Ann Otol Rhinol Laryngol83:304-31!, 1974 17. Pulec JL: Meniere's disease: Etiology, natural history, and results of treatment. Otolaryngol Clin North Am 6:25-40, 1973 18. Harker LA, McCabe BF: Meniere's disease and other peripherallabyrinthine disorders. In Paparella, Shurnrick (Editors), 3 pp 439-449

POSTGRADUATE MEDICINE • October 1977 • Vol. 62 • No. 4