Good Morning! Welcome Applicants! November 3, 2011 Patient’s Audiogram Normal Audiogram Classification *Conductive→ involving any cause that in some way limits the amount of external sound that gains access to the inner ear (usually temporary) • More common in children Sensorineural→ involving the inner ear, cochlea, or the auditory nerve (more likely permanent) Mixed→ which is a combination of conductive and sensorineural hearing loss. Central→ involving higher brain centers. Differential of Hearing Loss Conductive (outer and middle ear) Sensorineural (inner ear) Congenital microtia/atresia Genetic disorders External otitis In utero infection (CMV, measles, mumps, rubella, varicella, syphilis) Otitis media +/- effusion Anatomic abnormality of cochlea or temporal bone Trauma Ototoxic drugs Foreign Body (cerumen) Hyperbilirubinemia *Ossicular disruption (usually after trauma) Infection (meningitis, Lyme, Fifth dz, syphilis) Cholesteatoma Noise exposure TM perforation Radiation Temporal bone trauma Ischemia Introduction Hearing loss in the first years of life can cause delays in speech, language, and cognitive development 1 to 6 per 1,000 newborns and 2 per 1,000 young children With early intervention, hearing-impaired can reach same skill level of hearing peers Question 3-day-old infant failed otoacoustic emission testing (OAE). Prenatal and family histories are negative. Physical exam is normal. The next most appropriate step is: • A. Confirm the hearing loss with an auditory brainstem response test • B. Perform renal ultrasound • C. Refer to audiology at 1 year of age • D. Repeat OAE in 6 months • E. Treat with oral abx for possible middle ear effusion Screening AAP recommends congenital hearing loss be detected by 1 month, diagnosed by 3 months, and intervention started by 6 months Every state has universal newborn hearing screening • Otoacoustic emission testing (OAE) – detects evoked sound from the cochlea in response to clicks and tones • Auditory brainstem response (ABR) – measures the electroencephalographic waveform response from the vestibulocochlear nerve All Used to confirm abnormal OAE children ages 4 years and older should be screened regularly for hearing loss Acquired Hearing Loss History • Onset • Drainage • Tinnitus, vertigo, disequilibrium • Kidney or cardiac disease • Congenital infection, recurrent OM, meningitis • Trauma – noise exposure • Prematurity, hyperbilirubinemia • Family hx of hearing problems Acquired Hearing Loss Physical exam • Good head and neck exam • Ear exam Pneumatic otoscopy is performed with positive and negative pressure to evaluate mobility of the tympanic membrane Diminished or absent tympanic membrane mobility can be caused by fluid, mass in the middle ear cavity, perforation, pressure equalization tube, or sclerosis of the tympanic membrane. Increased mobility of the tympanic membrane can indicate ossicular chain disruption. Question Which of the following statements regarding hearing loss in infants and children is TRUE? • A. Chidren with external ear anomalies have sensorineural hearing loss more than conductive hearing loss • B. Cholesteatoma is the most common cause of conductive hearing loss • C. Language delay does not occur unless hearing loss is severe or profound • D. Newborn hearing screens should be performed only on premature infants or those with family hx • E. Parental concern for language delay is sufficient cause for auditory testing Office Hearing Tests 256 Hz and 512 Hz tuning forks • Hearing loss at 256 Hz is equivalent to approximately 10 to 15 decibels (dB), and hearing loss at 512 Hz is equivalent to 20 to 30 dB Office Hearing Tests Pure tone audiometry • Softest decibel threshold at which the child can hear a sound 50 percent of the time for each tested frequency • Normal hearing threshold is between 0 to 20 dB • Accurate results are dependent upon cooperation from the child • Any threshold >20 dB suggests a hearing loss (conductive, sensorineural, or mixed). Office Hearing Tests OAE Tympanometry • Valuable in conjunction with pneumatic otoscopy • *Flat tympanograms (type B tympanograms) and/or abnormal OAE testing may indicate conductive hearing loss, usually due to middle ear effusion Referral Any abnormal hearing screenings in the office should be followed by formal audiology Lab work-up Lab work-up Etiologies of Acquired Conductive Hearing Loss *Otitis media with effusion • Fluid filling the middle ear space prevents the tympanic membrane from vibrating adequately • Persistence of asymptomatic effusion following an episode of acute otitis media: 40% at 1 month 20% at 2 months 10% at 3 months • These pts. may benefit from tympanostomy tubes Etiologies of Acquired Conductive Hearing Loss TM Perforation Foreign Body Etiologies of Acquired Hearing Loss Cholesteatoma • Benign growth of stratified, squamous epithelium filled with desquamated cells and keratin • Erodes ossicular chain • Results from poor eustachian tube function Question A newborn who failed hearing screen, also has microcephaly, enlarged liver, and weight at 5th percentile. Pregnancy was uneventful, with normal prenatal labs, and there is no family history of hearing impairment. Most likely cause of hearing impairment is: • A. Alport syndrome • B. Congenital CMV • C. Middle ear effusion • D. Prenatal measles exposure • E. Waardenburg syndrome Etiologies of Hereditary Sensorineural Hearing Loss Usher syndrome Pendred syndrome Waardenburg *Alport syndrome → syndrome • Glomerular disease, ocular abnormalites, SNHL (progressive), family hx of hematuria, renal failure and deafness Mitochondrial disorders Etiologies of Acquired Sensorineural Hearing Loss Bacterial meningitis • *Most common cause of acquired deafness in childhood • 2.5 to 18% • Occurs early in the course (within first 48 hours) • *Prompt and complete hearing evalutaion initially and regular follow-up Etiologies of Acquired Sensorineural Hearing Loss *Ototoxic drugs Aminoglycosides (gent, tobra, amikacin, neomycin) Erythromycin Vancomycin Tetracycline Chemotherapy (cisplatin) Salicylates (reversible) Antimalarials Etiologies of Acquired Sensorineural Hearing Loss Noise exposure (acoustic trauma) • *High frequency hearing loss • Constant exposure to loud noises (personal listening devices, power tools, firearms) greater than 85 dB Or sudden noise (firecracker) greater than 140 dB • 12.5% of kids (age 6 to 19) have hearing loss in one or both ears Etiologies of Acquired Sensorineural Hearing Loss Trauma • Temporal bone fracture Bleeding from ear or hemotympanum Treatment Multidisiplinary approach • Audiology • ENT • Speech • Genetics Optho referral • Patients rely on sight for communication and learning Treatment Hearing based on etiology aids Cochlear implant Noon conference Toddler Behavior, Dr. Nass ROLL TIDE!