CSDS 131 Simple Hearing Tests

• Tuning Fork:

  • A metal device that emits a particular pitch when vibrated
  • The tines are struck against a firm, resilient surface while holding the stem
  • Intensity decreases over time
  • The larger the tuning fork, the lower the pitch
• Tuning Fork Uses:

  • To compare hearing of a patient to that of a presumably normal hearing examiner
  • To measure the relative sensitivity by AC (Air Conduction) and BC (Bone Conduction)
  • To examine the effects on BC when closing the opening into the ear
  • To determine the lateralization of sound to one ear or the other by BC
• AC = Air Conduction; BC = Bone Conduction

  • AC: sound travels from Outer Ear (OE), to Middle Ear (ME), to Inner Ear (IE)
  • BC: sound travels directly to Inner Ear (IE) only
• Occlusion Effect:

  • The increase in loudness of a tone presented by BC when the ear canal is closed
  • Primarily occurs for low-frequency sounds
  • Present in normal and sensorineural hearing loss, absent with conductive hearing loss
• Bing Test:

  • Tuning fork placed on mastoid
  • Patient/examiner alternately opens and closes the ear by pressing on the tragus
  • Patient reports if intensity of sound gets louder or remains the same
  • Based on the occlusion effect
• Findings of Bing:

  • Positive Bing: sound is perceived as louder or a pulsating sound, suggests normal hearing or sensorineural hearing loss
  • Negative Bing: sound intensity remains the same, suggests conductive hearing loss
• Limitations of Bing:

  • May get a response from the non-test ear
  • Frequency limitation of the tuning fork
• Weber Test:

  • Tuning fork placed on the forehead (midline)
  • Patient reports if they hear the sound in the right, left, or both ears (midline)
  • A test for lateralization
• Findings on Weber:

  • Midline sensation indicates normal hearing or equal amounts of the same type of hearing loss in both ears
  • Unilateral sensorineural hearing loss (inner ear) lateralizes to the better hearing ear
  • Unilateral conductive hearing loss (Outer Ear and/or Middle Ear) lateralizes to the poorer hearing ear
• Limitations of Weber:

  • Patients may not accurately report what they hear
  • Frequency of the tuning fork
• Schwabach Test:

  • Compares hearing of a patient with an examiner
  • Stem of the tuning fork alternately placed on the mastoid process of the patient and examiner
  • When no longer heard by the patient, the examiner measures the remaining time it's perceived
  • A Bone Conduction test
• Findings of Schwabach:

  • Normal Schwabach: both stop hearing it about the same time, suggests normal hearing
  • Diminished Schwabach: examiner hears the tone longer than the patient, suggests sensorineural hearing loss
  • Prolonged Schwabach: patient may hear the tone longer than the examiner, suggests conductive hearing loss
  • False Normal Schwabach: findings of the opposite ear seen with asymmetrical hearing loss
• Limitations of Schwabach:

  • Assuming the examiner has normal hearing
  • Difficult to identify mixed hearing loss
  • If asymmetrical hearing loss, may be stimulating the wrong cochlea
  • Information is only for the tested frequency
• Rinne Test:

  • Patient states if a tone sounds louder when presented by AC or by BC on the mastoid
  • Compares a person's BC hearing to their AC hearing sensitivity
• Findings of Rinne:

  • Positive Rinne: hears it louder by AC, normal hearing or sensorineural hearing loss (inner ear)
  • Negative Rinne: hears it louder by BC, conductive hearing loss (Outer Ear and/or Middle Ear)
• Limitations of Rinne:

  • Asymmetrical Hearing Loss
  • Mixed Hearing Loss
  • Findings only of the evaluated frequency
• Stenger Test:

  • Used to identify malingers/non-organic hearing loss
  • Compares two identical tones in both ears, only the louder one is perceived
  • Determines the threshold of hearing in each ear
• How to apply the Stenger Principle:

  • Introduce sound at different levels to each ear to determine if the patient accurately reports hearing it