SPPA 6400 Voice Disorders Structure and Function of Larynx.

SPPA 6400 Voice Disorders

Structure and Function of Larynx


Some questions What is a voice disorder? How does it differ from speech disorder? How does if differ from a resonance disorder? How common are voice disorders? Who gets a voice disorder? Why might someone have a voice disorder? How do you know if someone has a voice

disorder?


Voice Disorders: Simple Taxonomy Organic Neurogenic Functional


Prevalence vs. Incidence

Source: Manitoba Centre for Health Policy


From Roy et. al (2004) JSLHR 47 281-93.

Epidemiology



Epidemiology


Voice/laryngeal disorders is often a multidisciplinary effort Speech Language Pathology Otolaryngology Voice Scientists Vocal Instructors Neurology Gastroenterology Pulmonology Psychology


AssessmentWhat are the goals of assessment?


Assessment: Aims Etiology Diagnosis Prognosis Planning


Signs vs. Symptoms


Common Voice Symptoms (Table 2.1) Hoarseness Vocal fatigue Breathy voice Reduced phonational range Aphonia or voice loss Pitch breaks/inappropriately high pitch Strain/struggle Tremor Pain & other physical sensations


Primary components of Assessment Chart Review Case History Clinical Evaluation

Non-instrumented evaluation Instrumented evaluation Quality of life Indicators

Experimental/diagnostic therapy


Case History Voice Symptom History Voice Use History Health History Social/Vocational History Psychosocial History


Voice Symptom History The Voice Problem Effect of the Voice Problem History of the Voice Problem


Voice Use History

Establish voice use patterns On the job At home In social settings

Look for, Environmental factors (noise, air quality)


Health/Medical History Current health problems & past history Specific areas to probe

Respiratory problems Gastrointestinal problems Neurological problems Allergies Head and neck trauma, surgery, disease Prescription and OTC drugs Substance use: alcohol, tobacco, drugs, caffeine Exercise/diet considerations


Social/Vocational History


Psychosocial Interview “The voice is often a sensitive to our

emotional well being…” Ask about,

Stress/emotional problems Chronic or episodic

Hx of counseling


Clinical Evaluation Non-instrumented evaluation

Auditory perceptual evaluation of voice Maximal effort tasks Assessment of laryngeal musculoskeletal tension

Instrumented evaluation Videolaryngostroboscopy Acoustic evaluation Other selected instruments

Quality of life indicators Voice Handicap Index


Critical listening during history How do signs match symptoms? Signs of other communication impairment Variability in signs as a function of

Duration of session (change over time) Periods of improvement/resolution Automatic behaviors (e.g. cough, throat clear, laugh) Conversational content

Atypical vocal signs such as stridor (noise during respiration), tics, grunts, barks


Critical observation during history Signs of pain/discomfort Signs of tension/strain Respiratory patterns (“clavicular breathing”) Level of comfort (or anxiety) over the course of the

interview Signs of tremor, unusual movements of the body


Auditory Perceptual Evaluation

Standardized to clinic/profession Standardized with respect to

Data collection procedures (e.g. Alvin Clinic) Data evaluation procedures (e.g. CAPE-V) Data reporting procedures (be consistent)


GET HIGH QUALITY RECORDINGS OF VOICE!!!

You need

High quality recording device

High quality microphone

Easy access to recordings


Auditory Perceptual Signs Pitch Loudness Quality Aphonia Other Behaviors


Pitch Monopitch Inappropriate pitch Pitch breaks Diplophonia Reduced pitch range

Females Male


Loudness Monoloudness Excessive loudness variation Reduced loudness range


Quality Roughness Breathiness Strain/struggle/tension Tremor Sudden interruption of voicing (voice break) Hoarseness


Aphonia Aphonia vs. dysphonia Consistent vs. intermittent/episodic


Other Behaviors Stridor Excessive throat clearing/coughing


Scaling perceptual features of voice


Definitions of Vocal Attributes:OVERALL SEVERITY: Global, integrated impression of voice deviance.Roughness: Perceived irregularity in the voicing source.Breathiness: Audible air escape in the voice.Strain: Perception of excessive vocal effort (hyperfunction).Pitch: Perceptual correlate of fundamental frequency. This scale rates whether the individual'spitch deviates from normal for that person's gender, age, and referent culture. The direction ofdeviance (high or low) should be indicated in the blank provided above the scale.Loudness: Perceptual correlate of sound intensity. This scale indicates whether the individual'sloudness deviates from normal for that person's gender, age, and referent culture. The direction ofdeviance (soft or loud) should be indicated in the blank provided above the scale.

From ASHA Consensus on Auditory PerceptualEvaluation of Voice (CAPE-V)

Scaling perceptual features of voice


Other Tasks Phonational frequency range Loudness range Maximum phonation time

repeat 3 times, take largest value S/Z ratio

repeat 3 times, take largest value Laryngeal diadochokinesis (quickly repeated /a/

and/or /ha/) Voluntary cough


Assessment of Laryngeal Musculoskeletal Tension

“All patients with voice disorders, regardless of etiology should be tested for excess musculoskeletal tension, either as a primary or secondary cause of dysphonia”

(Aronson, 1990)


Instrumented Evaluation Videolaryngostroboscopy Acoustic Evaluation Selected Instruments


Laryngoscopy Direct Indirect

Mirror examination Rigid laryngeal endoscopy

Constant light Stroboscopy

Flexible fiberoptic laryngeal endoscopy Constant light Stroboscopy


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


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


Videolaryngostroboscopy (VLS) Why do it?


VLS Examination Evaluate structural integrity Evaluate gross mobility of structures Evaluate (inferred) vibratory patterns


VLS ExaminationRelevant structures True vocal folds Ventricular folds Arytenoids Interarytenoid area Epiglottis Glottic closure


Typical VLS ExaminationA task list Normal, loud and soft phonation Pitch glide (glissando) Cough Normal & deep breathing


Glottal closure patterns (Hirano & Bless,1993)


Stroboscopic observationsParameters for evaluating the stroboscopic image Symmetry of VF motion Periodicity Glottal closure configuration Horizontal excursion of the VFs Mucosal wave Phase closure Vocal fold edge Vibratory behavior


Example of a VLS evaluation form


Poburka BJ, Bless DM (1998) A multi-media, computer-based method for stroboscopy rating training JOURNAL OF VOICE 12 (4): 513-526

Methods of training individuals to rate stroboscopic examinations vary widely … Consequently, problems occur in both inter- and intrajudge agreement … This study attempted to determine if CAI could train individuals to make accurate and reliable visuo-perceptual judgments of stroboscopy… Following 4 to 5 hours of CAI training, the subjects with no previous experience demonstrated improved interjudge agreement with a panel of expert raters. The training was not effective for the experienced group. Regardless of the rater's experience, the parameters that required evaluation of movement were more difficult to rate than those requiring only an assessment of structure.


VLS Considerations Level of training (ASHA, 2004) Cleaning/Universal precautions Use of topical anesthetic


“Typical” acoustic measures Fundamental frequency and variability

mean Fo F 210 Hz M 110 Hz SDFo ~ 2-4 semitones

Vocal intensity and variability Mean 60-80 dB SD 10 dB

Perturbation measures (many ways to measure) Analysis must be limited to a phonated segment Jitter (0.2-1 %) Shimmer (0.5 dB – norms not well established)

Harmonic to noise ratio (> 15)

NOTE: these are ballpark figures. Always check actual tables for normative values.


Synthetic Continuum Varying in 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%


Typical acoustic measures Phonational frequency range

~ 3 octaves Dynamic range

50-115 dB 30 dB range

NOTE: these are ballpark figures. Always check actual tables for normative values.


Some Instruments for acoustic analysis

Real-time analysisExamples Sound level meter Visi-pitch Real-time spectrograms Nasometer

“Off-line” analysis (analysis after data is collected)Examples Computerized speech Lab (CSL), MDVP Cspeech (tf32) Praat


Other Measures Aerodynamic Measures Electroglottography (EGG) Electromyography (EMG)


Mean flow rate (MFR) Measures thought to reflect laryngeal valving ↑ = poor laryngeal valving ↓ = excessive laryngeal valving


Subglottal Pressure (Psg) Estimate

Repeated /pi/ with intraoral pressure transducer

Can measure for conversational loudness (5-10 cm water)

Can measure threshold (3-5 cm water)


Average glottal resistance Psg/Mean Flow Rate ↑ = hyperadducted state ↓ = hypoadducted state


Links to sites related to aerodynamic analysis

http://www.kayelemetrics.com/ Aerophone II

http://www.glottal.com/ Glottal enterprises pneumotachograph

Electroglottography (EGG)• Human tissue = conductor

• Air: conductor

• Electrodes placed on each side of thyroid lamina

• high frequency, low current signal is passed between them

• VF contact = impedance

• VF contact = impedance

Electroglottogram


Muscle Activity

Electromyography (EMG) is a way of recording muscle activity

Electrodes (needle or hook wire) inserted in the muscle

Used to Evaluate neuromuscular function Discriminating paralysis from arytenoid dislocation Verify location of needle for injecting BOTOX into

intrinsic laryngeal muscles


Quality of Life Indicators Voice Handicap Index (VHI) Voice-Related Quality of Life (V-RQOL)


Assessment ReportKey Components Covers key components of assessment

Need good description However, need to go beyond description

Voice diagnosis (or reason why not) Prognosis (or reason why not) Recommendations (it’s OK not to recommend Tx)

SPPA 6400 Voice Disorders Structure and Function of Larynx.

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Transcript of SPPA 6400 Voice Disorders Structure and Function of Larynx.