Transcript Document
Pure Tone Audiometry • • • • • • • • • Basic Principles of Sound The Audiometer Test Environment Patient’s Role Clinician’s Role Air Conduction Audiometry Bone Conduction Audiometry Audiogram Interpretation Masking Basics of Sound • Sound Waves and Propagation of Sound • Frequency (Hz) • Resonance • Intensity (The Decibel or dB) Audiometer • Generic Audiometer Audiometer • Clinical and Portable Audiometer Audiometer • Earphones Audiometer • Insert Earphone Audiometer • Bone Conduction Vibrator Audiometer • Computerized Audiometer Test Environment • Sound Treated Booth Test Environment • Circumaural Enclosures Test Environment • Quiet Room Patient’s Role • Hand Raising • Signal Button • Verbal Response • False Positives and False Negatives Clinician’s Role • Instructions • Patient’s Position • Placement of Earphones • Test Procedures for Screening • Test Procedures for Pure Tone Thresholds Clinician’s Role • Instructions • • • What are they listening for How to respond Verify they understand instructions Clinician’s Role • Position of Client - Adults and Children • Earphone Placement Clinician’s Role • Screening Test Procedures (adults) • • • Instructions Test Frequencies Disposition of Failures Clinician’s Role • Pure Tone Threshold Procedures • • • • • • Self-test Place earphones on patient Test better ear first Order of test frequencies Test other ear Use ASHA protocol for threshold testing. Clinician’s Role • Pure Tone Average (PTA) • • • Three tone average Two tone average Other methods Clinician’s Role • Degree of Hearing Loss based on PTA • • • • • • • None Slight Mild Moderate Moderately Severe Severe Profound Clinician’s Role • Role of Bone Conduction • • • Purpose Mastoid Placement Forehead Placement Audiograms • Basic Audiogram Audiograms • Symbols Audiograms • Type • Degree • Configuration Audiograms • Type of Loss - Conductive Audiograms • Type of Loss - Sensorineural Audiograms • Type of Loss - Mixed Audiograms • Configuration of Loss - Flat Audiograms • Configuration of Loss - Sloping (falling) Audiograms • Configuration of Loss - Rising Audiograms • Configuration of Loss - Tent Audiograms • Configuration of Loss - Mid-frequency or Cookie-bite Masking • Cross Hearing and Interaural Attenutation • Masking Defined • Rules • Types of Masking Noise Masking • Cross Hearing • Interaural Attenuation • • Definition Variables • • • transducers frequency individual variability Masking • Definition • Introduction of noise in NTE for the purpose of eliminating cross-hearing. Masking • Rule • Apply masking to NTE whenever the AC of the TE exceeds the BC for the NT cochlea by the amount of the minimum IA values. • Minimum IA values • • • Supraaural phones = 40 dB Insert phones = 70 dB Bone conduction = 0 dB Masking • Types of Masking Noise • • White Noise Narrow Band Noise Summary