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Home , Cholesteatoma, Conductive hearing loss, Ear pain, Hearing loss, Otitis, Otitis externa

Differential Diagnosis and Treatment of Loss JON E. ISAACSON, M.D., and NEIL M. VORA, M.D., Milton S. Hershey Medical Center, Hershey, Pennsylvania

Hearing loss is a common problem that can occur at any age and makes verbal communication difficult. The is divided anatomically into three sections (external, middle, and inner), and contributing to may strike one or more sections. Hearing loss can be cat- egorized as conductive, sensorineural, or both. Leading causes of include cerumen impaction, media, and . Leading causes of sensorineural hear- ing loss include inherited disorders, exposure, and . An understanding of the indications for medical management, surgical treatment, and amplification can help the family provide more effective care for these patients. (Am Fam Physician 2003;68:1125-32. Copyright© 2003 American Academy of Family )

ore than 28 million Amer- tive, the sound will be heard best in the icans have some degree of affected ear. If the loss is sensorineural, the hearing impairment. The sound will be heard best in the normal ear. of The sound remains midline in patients with hearing loss can be sim- normal hearing. Mplified by considering the three major cate- The compares air conduction gories of loss. Conductive hearing loss occurs with bone conduction. The tuning fork is when sound conduction is impeded through struck softly and placed on the mastoid bone the external ear, the , or both. Sen- (bone conduction). When the patient no sorineural hearing loss occurs when there is a longer can hear the sound, the tuning fork is problem within the or the neural placed adjacent to the (air conduc- pathway to the auditory cortex. Mixed hear- tion). In the presence of normal hearing or ing loss is concomitant conductive and sen- sensorineural hearing loss, air conduction is sorineural loss.

Evaluation TABLE 1 A thorough history and a careful physical Questions for Evaluating Hearing Loss examination are essential to the diagnosis and treatment of hearing loss. Pertinent questions When did your hearing loss begin? to ask patients are listed in Table 1. Was your hearing loss sudden, or has your hearing The physical examination begins with visu- slowly been getting worse? alization and palpation of the and peri- Does your hearing loss involve one or both ? auricular tissues. An should be used Have you been having ringing in your ear, fullness to examine the external auditory canal for in your ear, dizziness, ear drainage, or ear ? cerumen, foreign bodies, and abnormalities of Is there a history of hearing loss in your family? the canal skin. The mobility, color, and surface What is your job? What is the noise level in your workplace? of the tympanic membrane should Do you have a history of ear , ear , be determined (Figure 1).A pneumatic bulb is or straining to hear? required to accurately assess the tympanic Do you have a history of stroke, , or heart membrane and the aeration of the middle ear. ? Weber’s test is performed by softly striking a What are you currently taking? See page 1039 for 512-Hz tuning fork and placing it midline on Have you received any intravenous , definitions of strength- the patient’s scalp, or on the forehead, nasal diuretics, salicylates, or chemotherapy? of-evidence levels. bones, or teeth. If the hearing loss is conduc-

SEPTEMBER 15, 2003 / VOLUME 68, NUMBER 6 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 1125 Semicircular canals . ...... Cochleovestibular . . nerve . Carotid artery Tympanic . membrane .

Jugular vein Cochlea ILLUSTRATIONS BY CHRISTY KRAMES FIGURE 1. Anatomy of the ear.

better than bone conduction. Therefore, words understood at 40 dB above the speech sound is still heard when the tuning fork is reception threshold. placed adjacent to the ear canal. In the pres- ence of conductive hearing loss, bone conduc- Conductive Hearing Loss tion is better than air conduction, and the EXTERNAL EAR sound is not heard when the tuning fork is Complete occlusion of the ear canal by placed adjacent to the canal. cerumen is a frequent cause of conductive Whispering softly into the patient’s ear or hearing loss. Cotton-tipped applicators are holding a softly ticking wristwatch close to the notorious for worsening cerumen impaction. ear can be helpful in making a gross evalua- Warm water (body temperature) irrigation is tion of hearing. a safe method of removing cerumen in Once the ear has been examined and initial patients who have no history of , hearing tests have been done, the head and perforation of the tympanic membrane, or neck are examined, and the are otologic . Use of an otoscope and a evaluated. curette allows cerumen to be removed under Formal audiography is more sensitive and direct vision. The distance to the tympanic specific than a tuning fork examination and membrane must be kept in mind, because thus is essential in most patients with hearing do not allow for depth . loss. objectively measure hearing A variety of softening preparations are avail- levels and compare them with standards able if cerumen is too firm to remove. Aque- adopted by the American National Standards ous-based preparations, including docusate Institute in 1969.1 Normal hearing levels are sodium, sodium bicarbonate, and hydrogen 20 dB or better across all frequencies. The peroxide, are effective cerumenolytics.2,3 measures air conduction and bone Foreign bodies in the external auditory conduction and presents them graphically canal also can cause unilateral conductive across the hearing frequencies. Audiographi- hearing loss. These foreign bodies can be cally demonstrated conductive hearing loss removed by irrigation or with a curette. If the results in the air line falling below the bone object is not impacted or hygrostatic, warm line, creating an air-bone gap. water irrigation probably should be attempted Speech testing should be performed using first. If this approach is not effective, the for- standard word lists. The speech reception eign body can be removed with an instrument threshold is the sound level at which 50 per- if the patient is cooperative. If the patient is cent of presented words are understood. The uncooperative, removal in an operating room speech recognition score is the percentage of may be necessary.

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Otitis externa is an of the skin of the external auditory canal. Patients with oti- tis externa experience pain on manipulation of the pinna or , and their ear canal is edematous and filled with infectious debris. Conductive hearing loss may occur if swelling and debris occlude the canal. The most com- mon in are Pseudo- monas aeruginosa and .4 Treatment involves debridement of the canal, followed by the application of ototopical drops. In patients with severe otitis externa, a wick is placed in the ear for two to three days figure 2. Otoscopic view of osteoma of the to ensure delivery of the medication. Oral external auditory canal, showing tympanic antibiotics that are effective against P. aerugi- membrane (short arrow) and an osteoma (long arrow). nosa and S. aureus are helpful in patients with severe infection. The conductive hearing loss resolves after the subsides. Exostoses and osteomas are benign bony growths of the external auditory canal that interfere with normal cerumen migration, leading to occlusion and conductive hearing loss. Exostoses are multiple and bilateral, and are found adjacent to the tympanic mem- brane. Patients with exostoses often report a history of cold-water swimming. Osteomas are single and unilateral, and are found at the bony-cartilaginous junction (Figure 2).If symptomatic, exostoses and osteomas are removed surgically, but this is rarely necessary. Uncommon causes of external auditory FIGURE 3. Otoscopic view of perforation of canal obstruction include cysts and tumors. the tympanic membrane (white arrow) and Sebaceous cysts, fibromas, papillomas, adeno- myringosclerosis (yellow arrow). mas, sarcomas, , and melanomas also have been reported. If a is scopic examination and debridement are suspected, prompt is indicated. essential. Ototopical antibiotics ( [Floxin]) are necessary, and oral antibiotics MIDDLE EAR may be helpful. An accurate assessment of the Middle ear pathology may to conduc- patient’s tympanic membrane and hearing tive hearing loss. Perforations of the tympanic can be made only when the ear is dry. membrane cause hearing loss by reducing the Traumatic perforations of the tympanic surface area available for sound transmission membrane can occur because of water acci- to the ossicular chain (Figure 3).The main dents, , explosions, penetrating causes of tympanic membrane perforations injury, or fractures. Small per- are chronic otitis media and trauma. In forations (less than 2 mm) often heal sponta- patients who have had chronic otitis media neously.5 In the acute setting, blood may with tympanic membrane perforation, oto- obstruct the ear canal and prevent visualiza-

SEPTEMBER 15, 2003 / VOLUME 68, NUMBER 6 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 1127 Otitis media is the most common cause of conductive hear- Removed native ing loss in children. stapes

. tion of the membrane. Ototopical antibiotics and precautions to keep the ear dry are rec- Stapes piston prosthesis ommended. If the perforation or hearing loss persists beyond two months, the patient should be referred for consideration of surgi- cal correction. Trauma also can cause ossicu- lar injury or hemotympanum presenting as hearing loss. Otitis media is the most common cause of 6 conductive hearing loss in children. Middle FIGURE 4. : surgical repair of fix- ear effusions decrease the mobility of the tym- ated stapes caused by otosclerosis. Working panic membrane and the ossicular chain. This through an operation microscope, the surgeon loss of mobility results in an average hearing lifts the ear drum, removes the nonfunction- loss of 20 to 30 dB. The diagnosis of otitis ing stapes, and positions the prosthesis. media can be confirmed by and , and resolution of the effu- is an accumulation of squa- sion restores hearing. tubes are mous epithelium within the middle ear. This recommended for use in children with recur- mass may be seen in patients with otitis rent acute otitis media (more than three media. are divided into two episodes in six months or four episodes in one types: congenital and acquired. Congenital year), chronic middle ear effusions (more cholesteatoma presents as a pearly white mass than three months in duration), or significant located behind an intact tympanic membrane hearing impairment (greater than 30 dB along in a patient with unilateral conductive hearing with an effusion).7 [Evidence level C, consen- loss. Acquired cholesteatoma results from a sus opinion] retracted or perforated tympanic membrane with an ingrowth of epithelium. Cholestea- tomas are locally destructive and character- ized by chronic drainage. Conductive hearing The Authors loss caused by ossicular erosion is present in 8 JON E. ISAACSON, M.D., is assistant professor in the Division of Otolaryngology–Head 90 percent of patients with cholesteatomas. and Neck Surgery at Milton S. Hershey Medical Center Pennsylvania State University Longstanding cholesteatomas expand to College of , Hershey. Dr. Isaacson received his medical degree from the Uni- involve the mastoid, , and facial versity of Medicine and Dentistry of New Jersey–New Jersey Medical School, Newark, and completed a residency in otolaryngology–head and neck surgery at the Medical nerve. Suspicion of cholesteatoma warrants College of Virginia, Richmond. He also completed a fellowship in neuro- at the surgical consultation. Ear Foundation, Sarasota, Fla., and served as a clinical fellow in neuro-otol- Myringosclerosis of the tympanic mem- ogy and skull base surgery at the University of Zürich, Switzerland. brane develops in response to infection or NEIL M. VORA, M.D., is a resident in the Division of Otolaryngology–Head and Neck inflammation (Figure 3).Irregular white Surgery at Milton S. Hershey Medical Center. Dr. Vora received his medical degree from the University of Texas Science Center, Houston. patches consisting of calcium are visible on the membrane.9 Isolated myringosclerosis of Address correspondence to Jon E. Isaacson, M.D., Division of Otolaryngology–Head and Neck Surgery, Milton S. Hershey Medical Center, 500 University Dr., MC:H091, the tympanic membrane rarely causes signifi- Hershey, PA 17033. Reprints are not available from the authors. cant conductive hearing loss. However, exten-

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fashion. Clues to the diagnosis of conductive hearing loss are listed in Table 2.

Sensorineural Hearing Loss Sensorineural hearing loss encompasses disorders that affect the inner ear and the neural pathways to the auditory cortex. Al- though most patients with this type of hearing loss are adults, children also can be affected. Hereditary and nonhereditary congenital hearing loss are the two major pediatric classi- fications. The majority of hereditary losses are FIGURE 5. Otoscopic view of glomus tumor autosomal recessive and are frequently associ- (arrow). ated with other systemic findings. More than 100 congenital syndromes are associated with sive myringosclerosis, referred to as tympano- sensorineural hearing loss. sclerosis, involves the tympanic membrane, The consequences of delayed detection can ossicular chain, and middle ear mucosa, and be significant. Neonates considered at high causes significant conductive hearing loss by risk for congenital hearing loss (Table 3)11 tra- stiffening the entire system. ditionally have been screened, and 30 states Otosclerosis is characterized by abnormal now require universal newborn auditory bone deposition at the footplate (base of screening.12 The American Academy of Pedi- stapes). This bone deposition to fixation atrics and several other organizations endorse of the stapes at the oval window, preventing universal auditory screening. However, in normal vibration. Otosclerosis typically pre- 2001, the U.S. Preventive Services Task Force sents as progressive bilateral conductive hear- concluded that current “evidence is insuffi- ing loss in middle-aged white women. It is the cient to recommend for or against routine leading cause of conductive hearing loss in screening of newborns for hearing loss during adults who do not have a middle ear effusion the postpartum hospitalization.”13 or a history of otitis media.10 There is usually a positive family history. Treatment consists of amplification with hearing aids or surgical TABLE 2 repair by stapedectomy (Figure 4). Clues to the Diagnosis of Conductive Hearing Loss Glomus tumors are a rare cause of conduc- tive hearing loss (Figure 5).These neuro- Suggested cause of endocrine tumors arise from the adventitia of History Physical findings conductive hearing loss the jugular bulb or the neural plexus within Sudden painless Cerumen Complete canal the middle ear space. Characteristically, pa- loss of hearing occlusion tients presenting with glomus tumors are Sudden painful Narrow canal with debris Otitis externa women 40 to 50 years of age who report pul- loss of hearing Normal canal with red, immobile Chronic otitis media satile and hearing loss. On examina- tympanic membrane tion, a pulsating reddish-blue mass may be Gradual painless Immobile tympanic membrane Middle ear effusion seen behind an intact tympanic membrane. loss of hearing Normal mobile tympanic membrane Otosclerosis Reddish-blue pulsating mass Glomus tumor or However, diagnosis of these tumors is diffi- behind intact tympanic membrane vascular anomaly cult, and computed tomography of the tem- Retracted or perforated tympanic Cholesteatoma poral bones is required. An anomalous carotid membrane, with chronic drainage artery or jugular bulb may present in a similar

SEPTEMBER 15, 2003 / VOLUME 68, NUMBER 6 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 1129 ability are affected. consultation is TABLE 3 recommended for accurate testing and con- High-Risk Indicators* of Hearing Loss sideration of amplification, if appropriate. in Infants and Young Children Noise trauma is the most common pre- ventable cause of sensorineural hearing loss. Birth to 28 days The noise source may be occupational, recre- Family history of permanent sensorineural hearing loss during childhood ational, or accidental. Gunfire, explosions, and In utero infection (e.g., toxoplasmosis, , infection, loud music can cause irreversible hearing herpes) impairment. High frequencies are affected Ear or other craniofacial abnormalities first, typically at 4,000 Hz, followed by middle Illness or condition requiring admission to neonatal intensive care unit for at least 48 hours and lower frequencies. The hearing loss is Physical features or other stigmata associated with a syndrome known to accompanied by high-pitched tinnitus. include sensorineural or conductive hearing loss Aggressive use of noise protection is recom- 29 days to 24 months mended to prevent this form of hearing loss. Parental or caregiver concern about hearing, speech, , or The use of foam-insert decreases developmental delay noise exposure by 30 dB. Family history of permanent hearing loss during childhood A less common cause of hearing loss is oto- Physical features or other stigmata associated with a syndrome known to include sensorineural or conductive hearing loss or eustachian tube toxin exposure, typically from diuretics, sali- dysfunction cylates, aminoglycosides, and many chemo- Head trauma theraupetic agents. These medications must Postnatal infection associated with sensorineural hearing loss (e.g., ) be administered carefully in patients who are In utero infection (e.g., toxoplasmosis, rubella, cytomegalovirus infection, elderly, have poor renal function, require a herpes, ) prolonged course of medication, or require Neonatal indicators: hyperbilirubinemia requiring exchange transfusion, simultaneous administration of multiple oto- persistent pulmonary associated with mechanical ventilation, conditions requiring extracorporeal membrane oxygenation toxic agents. Patients with ototoxin exposure Syndromes associated with progressive hearing loss (e.g., , may experience hearing loss or dizziness. , Usher’s syndrome) Autoimmune hearing loss has been diag- Neurodegenerative disorders (e.g., Hunter’s syndrome) or sensory motor nosed with increasing frequency since the neuropathies (e.g., Friedreich’s ataxia, Charcot-Marie-Tooth disease) 1980s. Patients present with rapidly progres- Head trauma sive bilateral sensorineural hearing loss and Recurrent or persistent otitis media with effusion for at least three months poor speech discrimination scores, and they also may have or disequilibrium. *—These indicators are red flags and may help physicians in referring children Hearing loss progresses over three to four for audiologic testing. months, and an associated autoimmune dis- Information from Joint Committee on Infant Hearing. Year 2000 position state- order may be present. Symptoms usually ment: principles and guidelines for early hearing detection and intervention pro- grams. Pediatrics 2000;106:809-10. improve with the administration of oral pred- nisone, and response to this steroid is cur- rently the best way to make the diagnosis. Low-dose methotrexate therapy is becoming BILATERAL HEARING LOSS an accepted alternative to long-term pred- Presbycusis is a symmetric, progressive nisone therapy.14 deterioration of hearing in elderly patients, and is a diagnosis of exclusion (Table 4).The etiology is a combination of inherited and Temporal bone fractures can cause unilat- environmental factors, including lifetime eral sensorineural and conductive hearing loss. noise exposure and tobacco use. High-fre- When the fracture line involves the bony quency hearing and speech discrimination labyrinth (cochlea or vestibule), sensorineural

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hearing loss occurs. Temporal bone are associated with , cere- Noise trauma is the most common preventable cause of sen- brospinal fluid leakage, and other intracranial sorineural hearing loss. injuries. Early consultation is essential, and prompt surgical intervention may be required. Trauma may cause rupture of the round or oval window membranes, with perilymph has been identified. The work-up consists of leaking into the middle ear (fistula). Patients serial audiometry to document a fluctuating experience abrupt loss of hearing, along with loss, vestibular testing to verify the diseased vertigo and tinnitus. Perilymph fistulas also ear, and radiographic imaging to rule out an may occur after straining, lifting, coughing, or acoustic tumor. Treatment includes a low-salt sneezing, and are managed with three to six diet, diuretics, and vestibular suppressants. weeks of bed rest, followed by surgical repair if Hearing aids are often ineffective because symptoms do not improve.15 patients suffer from poor speech discrimina- Meniere’s disease is another cause of sen- tion, as well as diminished tolerance to ampli- sorineural hearing loss. Patients report unilat- fied sound. Chemical labyrinthectomy with eral fluctuating hearing loss with aural full- is now a common nonsurgical ness, tinnitus, and episodic vertigo. Initially, option for control of vertigo if medical man- the hearing loss is in the low frequencies, but agement fails.16 higher frequencies are affected as the disease Idiopathic unilateral sudden sensorineural progresses. The etiology of Meniere’s disease hearing loss, defined as hearing loss of 30 dB remains unclear, but within a three-day period, is an urgent situa- (increased fluid pressure within the inner ear) tion.17 Associated symptoms include tinnitus,

TABLE 4 Clues to the Diagnosis of Sensorineural Hearing Loss

Suggested cause of sensorineural History Physical findings Audiogram hearing loss

Gradual hearing loss, noise Elderly patients with normal Bilateral, symmetric Presbycusis exposure, tobacco use tympanic membrane high-frequency loss Gradual hearing loss, Normal tympanic Bilateral, symmetric loss Noise-induced tinnitus, noise exposure membrane centered at 4,000 Hz traumatic loss Rapidly progressive hearing Normal tympanic membrane, Any abnormal Autoimmune loss, possibly fluctuating, with possible vertigo configuration with poor hearing loss bilateral loss or disequilibrium speech discrimination Sudden unilateral hearing Normal tympanic membrane; Any unilateral abnormal Perilymph fistula loss, tinnitus, vertigo, vertigo and , with configuration head trauma, straining positive pneumatic pressure Sudden, fluctuating, Normal tympanic membrane Unilateral low-frequency Meniere’s disease unilateral hearing loss, loss tinnitus, episodic vertigo Gradual unilateral hearing Normal tympanic membrane, Any unilateral abnormal Acoustic neuroma loss, tinnitus possible facial nerve configuration weakness and unsteadiness

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2. Jabor MA, Amedee RG. Cerumen impaction. J La State Med Soc 1997;149:358-62. 3. Mehta AK. An in-vitro comparison of the disinte- gration of human ear wax by five cerumenolytics commonly used in general practice. Br J Clin Pract 1985;39:200-3. 4. Clark WB, Brook I, Bianki D, Thompson DH. Micro- biology of otitis externa. Otolaryngol Head Neck Surg 1997;116:23-5. 5. Canalis RF, Abemayor E, Shulman J. Blunt and pen- etrating injuries to the ear and temporal bone. In: Canalis RF, Lambert PR, ed. The ear: comprehensive otology. Philadelphia: Lippincott Williams & Wilkins, 2000:785-800. 6. Bluestone CD, Klein JO. Otitis media, atelectasis, and eustachian tube dysfunction. In: Bluestone CD, Stool SE, Scheetz MD, eds. Pediatric otolaryngol- FIGURE 6. Magnetic resonance image showing ogy. 2d ed. Philadelphia: Saunders, 1990:320-486. an acoustic neuroma (arrow). 7. American Academy of Otolaryngology–Head and Neck Surgery. Bulletin (American Academy of Oto- laryngology–Head and Neck Surgery). 2000;19:2-50. 8. Edelstein DR, Parisier SC, Han JC. Acquired vertigo, and aural fullness. Speculative etiolo- cholesteatoma in the pediatric age group. Oto- gies include viral infections and vascular laryngol Clin North Am 1989;22:955-66. insults. Rarely, perilymph fistulas and acoustic 9. Forseni M, Eriksson A, Bagger-Sjoback D, Nilsson J, Hultcrantz M. Development of : neuromas are implicated. A history of upper can predicting factors be identified? Am J Otol respiratory infection within a month of the 1997;18:298-303. hearing loss is often described in patients who 10. Emmett JR. Physical examination and clinical evalu- ation of the patient with otosclerosis. Otolaryngol have a viral etiology. The work-up includes Clin North Am 1993;26:353-7. audiometry, followed by radiographic imag- 11. Joint Committee on Infant Hearing. Year 2000 ing to rule out an acoustic tumor. Patients position statement: principles and guidelines for early hearing detection and intervention programs. should begin treatment with oral steroids Pediatrics 2000;106:798-817. within three weeks. One study found that 12. Finitzo T, Crumley WG. The role of the pediatrician patients with minimal hearing loss, no in hearing loss. From detection to connection. Pediatr Clin North Am 1999;46:15-34. vestibular symptoms, and early treatment 13. U.S. Preventive Services Task Force. Guide to clini- have better outcomes.18 cal preventive services: report of the U.S. Preventive Patients with acoustic neuromas present Services Task Force. 3d ed. Alexandria, Va.: Inter- national Medical Pub., 2002. with unilateral sensorineural hearing loss 14. Salley LH Jr, Grimm M, Sismanis A, Spencer RF, approximately 10 to 22 percent of the time19 Wise CM. Methotrexate in the management of (Figure 6).Patients with asymmetric sen- immune mediated cochleovestibular disorders: clinical experience with 53 patients. J Rheumatol sorineural hearing loss require evaluation for a 2001;28:1037-40. retrocochlear tumor. Acoustic neuromas and 15. Kohut RI, Hinojosa R, Ryu JH. Update on idiopathic other cerebellopontine-angle tumors need to perilymphatic fistulas. Otolaryngol Clin North Am 1996;29:343-52. be ruled out. Magnetic resonance imaging of 16. Blakely BW. Update on intratympanic gentamicin the brain with gadolinium continues to be the for Meniere’s disease. Laryngoscope 2000;110(2 pt gold standard for diagnosing these masses. 1):236-40. 17. Hughes GB, Freedman MA, Haberkamp TJ, Guay ME. Sudden sensorineural hearing loss. Otolaryn- The authors indicate that they do not have any con- gol Clin North Am 1996;29:393-405. flicts of interest. Sources of funding: none reported. 18. Wilson WR, Byl FM, Laird N. The efficacy of steroids in the treatment of idiopathic sudden hearing loss. REFERENCES A double-blind clinical study. Arch Otolaryngol 1980;106:772-6. 1. American National Standard specifications for 19. Moffat DA, Baguley DM, von Blumenthal H, Irving audiometers. New York: American National Stan- RM, Hardy DG. Sudden in vestibular dards Institute, 1969. . J Laryngol Otol 1994;108:116-9.

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