Final Review

• Prenatal factors of hearing loss: Maternal infections during pregnancy, Maternal history of gestational diabetes, TORCH infections, Maternal substance abuse during pregnancy
• TORCH: toxoplasmosis, Other agents, Rubella, Cytomegalovirus, Herpes simplex
• postnatal factors of hearing loss: Prematurity, Low birth weight, Lack of oxygen, Prolonged labor, Jaundice, NICU stay
• family history is important because 50-60% of hearing loss is genetic in origin
• Toddler risk factors: history of ear infections, allergies, medications, history of trauma, prior surgeries, seizure disorders
• Behaviors that may indicate toddler hearing loss: Listening to the TV “too loud”, Difficulty accurately following directions, Difficulty responding to questions, Inattentiveness, Academic issues in preschool
• if a child has risk factors of hearing loss, it could be adhd, receptive language disorder, capd, home life, learning disabilities, ASD, expressive language delay, childhood apraxia of speech
• There are more data sources for acquiring information in school-aged children because they begin to spend more time out with other than with just parents
• Motor restlessness: “hyperactivity"
• Questions related to hearing status: Can you describe the hearing problem and any related symptoms?
• Questions related to assistive devices: Do you use a hearing aid or other assistive device?
• Questions related to hearing history: Is there an occupational or recreational history of noise exposure?
• otoscopic evaluation: Evaluation of the ear canal and tympanic membrane using an otoscope
• Otoscope: hand held tool with a speculum and light source
• Otoscopic evaluation steps: Hold handle firmly and comfortably like a pencil, Make sure subject is seated comfortably, Examine pinna for irregularities and scars, Grasp helix of ear and pull slightly upward and backward (to straighten ear canal), Insert speculum gently until first bend, Look into eyepiece of otoscope, Examine entire TM
• Otoscopic evaluation looks for Clear/unobstructed ear canal, Presence or absence of excessive cerumen, Landmarks in the tympanic membrane, Typical color and appearance of each structure, Typical TM is pearly gray and translucent, Make note if TM is intact, retracted, bulged, perforated, scarred, or thinned
• Landmarks of the tympanic membrane to look for in the otoscopic evaluation: Pars flaccid, Pars tensa, Umbo, Handle of malleus, Cone of light
• Retracted tympanic membrane

  
• Perforated tympanic membrane

  
• bulged tympanic membrane (secondary to otitis media)

  
• pure tone audiometry: Key hearing test to identify hearing threshold levels of an individual
• pure tone audiometry Tells us the degree, type, and configuration of hearing loss
• pure tone audiometry is a Subjective behavioral measurement because it relies on patients’ responses to stimuli
• steps for pure tone audiometry:

  1. Start at 1000 Hz at 40 dB HL, and tell patient to respond when they hear something
  2. Every time the patient can hear the sound, decrease by 10 dB. Every time they cannot hear the sound, increase by 5 dB
  3. The minimum dB level at which the patient responds 50% of the time is their threshold at that frequency
  4. Repeat steps for 2000, 4000, 8000, 250, & 500 Hz tones
• PTA = Average of thresholds from 500Hz, 1KHz, 2KHz, 4KHz
• Pure tone average: average of 500, 1000, and 2000 Hz
• Masking: When a “better ear” might inadvertently assist the “more affected ear,” your results might not be as accurate
• Solution to masking: provide making noise in better ear (over ear headphones for 40 dB difference or insert headphones with 55dB difference)
• If two of the patient’s back-to-back testing frequencies have a difference of 25 dB or more, mid frequencies should be tested
• Normal hearing: -10 to +15 dB HL
• Minimal hearing loss: 16– 25 dB HL
• Mild hearing loss: 26 – 40 dB HL
• Moderate hearing loss: 41 – 55 dB HL
• Moderate-severe hearing loss: 56 – 70 dB HL
• Severe hearing loss: 71 – 90 dB HL
• Profound hearing loss: > 90 dB HL
• bilateral sensorineural hearing loss

  
• Bilateral conductive hearing loss

  
• Unilateral sensorineural hearing loss
• Bilateral mixed hearing loss