1. Instrumental Assessment
SPPA 6400 Voice Disorders: Tasko

2. Ways to Assess the Utility of Instrumentation
Does it help detect the existence of a voice problem?
Can it help establish the severity of progression of a voice problem?
Can it help differentially diagnose a voice problem?
Can it be used as a treatment tool, in the form of biofeedback, behavioral modification or patient education?
SPPA 6400 Voice Disorders: Tasko

3. Selected Instrumental Techniques
Acoustic Analysis
Aerodynamic Analysis
Laryngeal Imaging
Electroglottography (EGG)
Electromyography (EMG)
SPPA 6400 Voice Disorders: Tasko

4. Acoustic Analysis of Voice
SPPA 6400 Voice Disorders: Tasko

5. Recording Considerations
Equipment
Microphone and preamplifier setup
Handheld, headset, dynamic mic, condenser mic
Device onto which signal is recorded
Computer, dedicated recording device
Optimizing Recording
Microphone Position
Recording levels
Digital-to-audio conversion settings
SPPA 6400 Voice Disorders: Tasko

6. Analysis Considerations
Real-time analysis
Examples
Sound level meter
Visi-pitch
Real-time spectrograms
“Off-line” analysis (analysis after data is collected)
Computerized speech Lab (CSL), MDVP
Cspeech (tf32)
Praat
Speech Tool
Wavesurfer
SFS
SPPA 6400 Voice Disorders

7. SPPA 6400 Voice Disorders: Tasko
Voice Signal Typing
Type I
Quasiperiodic, continuous signal
Single cluster of dominant F0 values
F0 and traditional perturbation analysis can be used.
Type II
Random or periodic modulations that fluctuate too much to detect a single recurring F0.
Analysis limited to spectral analysis.
Type III
Random aperiodic signals with no identifiable fundamental frequency whatsoever.
Not appropriate for most acoustic analysis.
SPPA 6400 Voice Disorders: Tasko

8. SPPA 6400 Voice Disorders: Tasko
Voice Signal Typing
Type I
Type II
Type III
SPPA 6400 Voice Disorders: Tasko

9. Fundamental Frequency (F0)
Average F0
speaking fundamental frequency (SFF)
Correlate of pitch
Infants
~ Hz
Boys & girls (3-10)
~ Hz
Young adult females
~ 200 Hz
Young adult males
~ 120 Hz
Older females: F0 ↓
Older males: F0 ↑
F0 variability
F0 varies due to
Syllabic & emphatic stress
Syntactic and semantic factors
Phonetics factors (in some languages)
Provides a melody (prosody)
Measures
F0 Standard deviation
~2-4 semitones for normal speakers
F0 Range
maximum F0 – minimum F0 within a speaking task

10. Intensity Average Intensity Correlate of loudness conversation:
~ dBSPL
Intensity Variability
 SPL to mark stress
Contributes to prosody
Measure
Standard deviation for neutral reading material:
~ 10 dBSPL

11. Perturbation Analysis
Jitter: variability in the period of each successive cycle of vibration
Shimmer: variability in the amplitude of each successive cycle of vibration …

12. Synthetic Continuum of Jitter
0.0% 2.0%
0.2% 2.5%
0.4% 3.0%
0.6% 4.0%
0.8% 5.0%
1.0% 6.0%
1.5%
SPPA 6400 Voice Disorders

13. Harmonics-to-noise Ratio
Harmonic peak
Noise ‘floor’
Amplitude
Harmonic peak
Noise ‘floor’
Frequency

14. Cepstral Based Measures

15. Cepstral Based Measures

16. Cepstral Based Measures

17. Other acoustic measures
Maximum Phonational Frequency Range
Highest F0 - Lowest F0
Dynamic range
Highest intensity – lowest intensity
Voice Range Profile/Phonetogram
Dynamic range from lowest to highest F0
SPPA 6400 Voice Disorders

18. SPPA 6400 Voice Disorders: Tasko
Voice Range Profile
SPPA 6400 Voice Disorders: Tasko

19. Aerodynamic Analysis of Voice
SPPA 6400 Voice Disorders: Tasko

20. SPPA 6400 Voice Disorders: Tasko
Aerodynamic Testing
SPPA 6400 Voice Disorders: Tasko

21. SPPA 6400 Voice Disorders: Tasko
Aerodynamic Testing
SPPA 6400 Voice Disorders: Tasko

22. SPPA 6400 Voice Disorders: Tasko
Aerodynamic Testing
Average Flow Rate
Typical values ml/sec
Hyperfunction associated with lower values
Hypofunction associated with higher values
Subglottal Pressure
Typical values 5-8 cm H20
Phonation Threshold Pressure (PTP)
Minimum pressure needed to initiate phonation
Typical values 3-5 cm H20
Laryngeal Airway Resistance (LAR)
subglottal pressure/mean flow rate
Estimates the resistance at level of the larynx
SPPA 6400 Voice Disorders: Tasko

23. SPPA 6400 Voice Disorders: Tasko
Laryngeal Imaging
SPPA 6400 Voice Disorders: Tasko

24. Laryngeal Imaging Direct Laryngoscopy Indirect Laryngoscopy
Mirror examination
Rigid laryngeal endoscopy
Constant light
Stroboscopy
Flexible fiberoptic laryngeal endoscopy
SPPA 6400 Voice Disorders

25. Components Endoscope (rigid or flexible)
Light source (constant or strobe)
Camera
Recording device (VHS, computer)
If strobe light is used, a neck mounted microphone (or electroglottograph) is used for tracking Fo
SPPA 6400 Voice Disorders

26. Constant light vs. strobe light
Constant light source allows viewing of basic structure and function
Identify lesions
Identify abnormalities in ab/adduction
Identify supraglottic activity
Strobe light source allows a view of “simulated” vibration
allows assessment of the vibratory function of the vocal folds
May reveal structural abnormalities not seen during constant light endoscopy
SPPA 6400 Voice Disorders

27. Typical VLS Examination
A task list
Normal, loud and soft phonation
Pitch glide (glissando)
Laryngeal diadochokinesis - /i i i/ /hi hi hi/
Cough
Normal & deep breathing
SPPA 6400 Voice Disorders

28. SPPA 6400 Voice Disorders: Tasko
Gross Observations
Glottic Closure
Supraglottic hyperfunction
Mucus
General Appearance
Mobility
SPPA 6400 Voice Disorders: Tasko

29. Stroboscopic observations
Glottic Closure
Phase Closure
Symmetry
Amplitude
Mucosal wave
Stiffness/nonvibrating portion/adynamic segment
Periodicity
SPPA 6400 Voice Disorders

30. Example of a VLS evaluation form
SPPA 6400 Voice Disorders