Screening Tests for DISORDERS!!! Or Crusading the Clinic

Audiometry (Mencher Chapter 3) Basic hearing test  Sine waves 125 – 8000 Hz  Speech range Few audiometers test over 10 kHz If Tinnitus  Narrow band noise  Warble tones Narrow frequency range Allows differentiation from tinnitus

More Audiometry Variables Insert earphones vs. supra-aural earphones Reduce background noise (25 vs. 6 dB HL, respectively) Interaural attentuation Collapsed ear canal  Masking Noise Isolate hearing in one hear Eliminate ‘good ear’ Bone Conduction  By-pass middle ear  Bone to cochlea Earphone vs. Bone conduction comparison

Tympanometry Tympanogram  Maps pressure vs. mobility  Response of Tympanic Membrane Normal = smooth curve (no asymetry) Flat Response  Effusion  Ossification Peaked response  Perforation  Efficiency of Middle ear Acoustic Reflex  Reflex of stapedial muscle 85 dB Hl stimulus  Presence/Absence  Timing of response Cerumen build-up to Retrocochlear abnormalities

Acoustic Brainstem Response Acoustic brainstem response (ABR)  Procedure: Present Click or tone pip  Use electrodes to measure brainstem response Magnitude  Normal range Latency  Acoustic Neuroma Unresponsive subjects  Baby hearing