This document provides an overview of common audiology tests and procedures, including: - Pure Tone Audiometry (PTA) for determining hearing threshold levels - Tympanometry to assess middle ear function by measuring ear canal volume, peak pressure, and compliance - Speech audiometry tests word recognition ability - Acoustic reflex testing and decay measures the response of the stapedius muscle to sound - Auditory evoked potentials involve measuring electrical potentials from the brain in response to sounds.

2. Audiology in Brief
Dr. Rabiei

13. PTA

34. Tympanometry

35. Ear Canal Volume
• “The equivalent ear canal volume (ECV):
• volume of air medial to the probe, which includes the volume
between the probe tip and the tympanic membrane
• Averages:
• Children 3 – 5yrs: 0.4cc to 1.0cc
• Adults: 0.6cc to 1.5cc
• Ear canal volume with an ECV >2.0 with a type B tympanogram in
children suggests a perforated TM or patent grommet.
• Very small ECV with a type B tympanogram suggested impacted
wax or middle ear pathology (glue ear?).

48. Tympanometric Peak
Pressure/Middle Ear Pressure
• Tympanometric peak pressure (TTP) or middle
ear pressure (MEP) is the ear canal pressure at
which the peak of the tympanogram occurs
(Margolis & Hunter, 2000).

49. Static Compliance
• Static compliance (SC) “is the greatest amount
of acoustic energy absorbed by the middle ear
system (the vertical peak of the tympanic
tracing)” (Onusko, 2004, p. 1716).

50. • Gradient
“Tympanogram gradient is an objective
measure that describes the steepness of the
slope of the tympanogram near the peak”
(Fowler & Shanks, 2002, p.182). The gradient
is not commonly used in Australia to analyse
tympanograms.

61. Speech Audiometry

95. Acoustic reflex decay
• Using acoustic immittance measures similar to those used to
observe acoustic reflex thresholds.
• In clinical situations, instead of the short-duration stimulus , a
stimulus of about 10 seconds is presented.
• This stimulus is presented at 10 dB above the acoustic reflex
threshold level to observe a robust acoustic reflex response.
• The stimulus is presented to ear contralateral to ear with probe.
• The resulting change in admittance of sound is observed at the
onset of the stimulus, over the duration of the stimulus
presentation , and at the stimulus offset.
• Under normal circumstances, the acoustic reflex decay
will less than half of the maximum change in admittance over the 10-
second recording interval.
Abnormal acoustic reflex decay raises suspicion
of retrocochlear pathology

105. Auditory Evoked Potentials Tests