Voice Midterm

Amplification

Amplification

increasing the magnitude of a signal

Amplifier Gain

exact magnitude of amplification

Amplifier Linearity

degree to which gain is constant across all input
magnitudes

Filters

reshape the acoustic waveform to eliminate selected energy above or below a certain frequency range

Importance of Acoustic Measurement

• Can provide objective and noninvasive
  analysis of vocal function

What are 5 Common Acoustic Measures

• Fundamental frequency

• Intensity

• Perturbation measures

• Ratio to signal-energy to noise

• spectral or cepstral features

Fundamental Frequency

the rate of vibration of the vocal folds and is expressed in Hertz (Hz) or cycles per second (cps)

Intensity

• referenced to sound pressure level (SPL) and
  measured on a logarithmic decibel (dB) scale

• Vocal intensity is the acoustic correlate of vocal
  loudness

Perturbation Measures

Cycle-to-cycle variability in a signal (typically
measured from sustained vowel productions or
“extracted” vowels from connected speech).
• Jitter = cycle-to-cycle variability in frequency
(a.k.a. frequency perturbation, pitch
perturbation).
• Shimmer = cycle-to-cycle variability in amplitude
(a.k.a. amplitude perturbation).
• Calculation requires a quasi-periodic signal for
reliable/valid perturbation analysis (i.e., Type I
signal).
Perturbation Measures

Jitter vs. Shimmer

• Jitter = cycle-to-cycle variability in frequency
(a.k.a. frequency perturbation, pitch
perturbation).
• Shimmer = cycle-to-cycle variability in amplitude
(a.k.a. amplitude perturbation).

Glottal Fry

• should be observed for when doing oral mech exam

• Kourtney K voice

Diplophonia

the production of two separate tones during a single voice

Spasmodic Dysphonia (SD)

• Adductor Spasmodic Dysphonia

• Abductor Spasmodic Dysphonia

• Mixed Spasmodic Dysphonia

Adductor Spasmodic Dysphonia

Strained-strangled voice with voice stoppages/spasms.

Abductor Spasmodic Dysphonia

Involuntary breathy bursts/spasms.

Mixed Spasmodic Dysphonia

Both strained voice stoppages and breathy bursts.

Vocal Fold Nodules

Age and Gender Trends:
– Children (boys > girls, 3:1 ratio),
– Adults (women > men, rare among post-pubescent and adult males).
• Possible Personality Factors (Women with Nodules):
– Extraverted (talkative),
– Socially Dominant,
– Stress Reactive (tense), Aggressive,
– Impulsive.
• Occupational factors: singers; professions with extended teachers).

Mild to Moderate Dysphonia
– Roughness, breathiness related to gaps anterior and posterior to
lesions, increased muscular tension.
• Severity of dysphonia varies depending upon:
– extent (size) of lesions,
– Length of time since onset (type of nodules, chronic vs. acute),
– Degree of accompanying inflammation.
• Treatment:
– First line = voice therapy,
– Surgical Removal by “skilled” laryngologist and only...
• If/when patient has been compliant with voice therapy, but did not
respond completely/satisfactorily,
• Surgery to be followed by post-surgical voice therapy

Vocal Fold Polyps

• Fluid-filled, exophytic lesion composed of gelatinous
material in SLLP with active blood supply (typically located
on middle third of the VF).
– Most often seen in adults,
– Often unilateral, but can be bilateral.
• Types:
– Sessile (blister-like),
– Pedunculated (attached to a stalk).
• Cause(s):
– Acute Vocal Trauma (i.e, phonotrauma).
• Voice Effects:
– Mild to severe dysphonia depending upon:
• Size, type, and location (and associated mass and stiffness effects),
• Degree of interference with glottic closure and VF vibration,
• Presence of hemorrhagic blood vessel “feeding the lesion.”

Treatment:
– Voice Conservation/Rehabilitation (primary)
– Phonosurgery (and voice rehab)

Vocal Fold Cysts

• Fluid-filled, typically unilateral, sessile lesions (sacs) on cephalic
surface or medial edge of the VF that can be:
– Congenital or Acquired.
– Embedded in SLLP, but often extend into ILLP and DLLP (i.e., the vocal ligament).
• No clear etiology, but...
– Mucous gland blockage, and/or
– Phonotrauma

• Treatment: Surgical excision/dissection of the cyst off of the vocal ligament (from a superior and lateral approach to avoid scarring of the vocal fold)
  

Reinke’s Edema

• SLLP becomes filled with viscous, gelatinous fluid.
• “Polypoid degeneration” is a severe form of edema wherein the
entire membranous VF is filled with fluid.
• Etiologic Factors:
– Chronic Phonotrauma,
– Smoking.
• Vibratory Effects
– Increased mass and stiffness.
• Voice Effects:
– Signature low pitch and husky hoarseness described as a “whiskey”
or “smoker’s” voice.
• Surgery (accompanied/preceded by smoking cessation
program).
– Pre- and post-operative voice therapy.

Granuloma

unilateral or bilateral, vascular and inflammatory
exophytic lesions related to tissue irritation in the posterior larynx typically on medial surface of arytenoid cartilage(s).

• S/S include:
  – Pain, sore throat, with or without voice change (i.e., Posterior site of
  lesion(s), may not affect VF vibration).

• Two Primary Etiologies:
  – “Mechanical” or “Chemical” tissue irritants of posterior larynx...
  • Mechanical = endotracheal intubation,
  • Chemical = laryngopharyngeal reflux.
  – Persistent Voice Misuse...
  • Pressed, low-pitched voice with excess tension.

Contact Ulcer

ulcerated lesion on the same site often on
opposite side of granuloma (cup/saucer relationship).

• S/S include:
  – Pain, sore throat, with or without voice change (i.e., Posterior site of
  lesion(s), may not affect VF vibration).

• Two Primary Etiologies:
  – “Mechanical” or “Chemical” tissue irritants of posterior larynx...
  • Mechanical = endotracheal intubation,
  • Chemical = laryngopharyngeal reflux.
  – Persistent Voice Misuse...
  • Pressed, low-pitched voice with excess tension.

Fundamental Freq =’s…

Pitch

S/z ratio

an assessment used to look at respiration

• times the longest duration of /s/ and /z/ phonemes to analyze phonation and respiration capabilities 

• Typical ratio with vocal fold problems is around 1.4 and would want the ratios to be the approximately the same

Phonation threshold pressure (PTP)

amount of pressure needed for VF vibration

Subglottal Pressure

the pressure of the air coming up through the vocal chords from beneath.

Laryngeal Resistance

the quotient of peak intraoral pressure
(estimated from the production of an unvoiced
/p/) divided by the peak flow rate (measured
from the production of a vowel /i/) produced in
a repeated train of /pi/ syllables.

Intended to reflect overall resistance of the
glottis and estimates laryngeal valving function
(cm H20/l/sec).
– Hyperfunction (valve too tight): LR too high
– Hypofunction (valve too loose): LR too low
– Normal (as compared to normative values)

How do the intrinsic laryngeal muscles work?

Synergistically

Cricoarytenoid Joint

serves to abduct and adduct the vocal folds

Cricothyroid Joint

serves to abduct and adduct the vocal folds

5 layers of the vocal folds

epithelium, lamina propria (superficial, intermediate, deep), vocalis muscle

Epithelium

Outermost, mucosal layer, thin pliable capsule
– Thin layer of slippery mucous lubrication needed for
vocal folds to oscillate best
• Mucociliary blanket covers epithelium
– Mucinous layer (outermost viscous protective layer)
– Serous Layer (watery layer with cilia)
• Epithelium
– Exposed to environmental influences
• Humidity
• Dehydration
• Pollution
• Reflux
• Basement Membrane Zone (BMZ)-transition zone

Lamina Propria

• Three layered Structure
– Superficial layer (SLLP)
– Intermediate (middle) layer (ILLP)
– Deep layer (DLLP)
• Each layer composed of distinct concentrations of
fibrous proteins (connective tissue)
– Elastin (allows tissue to deform/stretch)
• Most concentrated in SLLP and ILLP
– Collagen (less stretch, but tolerates stress and provides
tensile strength)
• Most concentrated in ILLP and especially in DLLP
– As progress from superficial to deep layers of the LP there
is increasing density/stiffness
– LP vibrates passively in response to aerodynamic forces

Lamina Propria continued

Superficial layer (SLLP) - a.k.a. “Reinke’s Space”
– Loose and Flexible
– Soft, slippery, gelatin-like substance
– Vibrates significantly during phonation
• Intermediate (middle) layer (ILLP)*
– Mostly elastin fibers (some collagen)
– Also vibrates during phonation
• Deep layer (DLLP)*
– Mostly collagen fibers (fewer elastin fibers)-most dense layer of LP
– Interspersed with muscle fibers to join LP to underlying vocalis
muscle
*Note: The combined intermediate and deep layers of the lamina
propria is also known as the “Vocal Ligament”.

Vocalis Muscle

Fifth histological layer (most dense)
• Forms the “body” of the vocal fold and
provides:
– Tone
– Stability
– Mass
• Vocalis still oscillates during vocal fold
vibration (but not as much as cover and
transition layers of VF)

How do lengthening and thickening relate to pitch

More lengthening = high pitch

More thickening = low pitch

Stroboscopy

A special lighting technique wherein a stroboscopic light
flashes at specific moments to form a composite vibratory
cycle, derived from many single points along multiple
cycles.
• The strobe light flashes at a phase point in VF vibration that is slightly faster than the Fo. Each successive flash captures a series of separate images, sampled from different points of VF vibration.
• Stroboscopy produces an apparent (not real!!) slow motion effect.
• Like other measures, significant aperiodicity in the voice, compromises the clinical utility of stroboscopy because a “stable” fundamental frequency can not be extracted.

What is the most common type of imaging?

stroboscopy

What does the GRBAS measure?

G: Grade or a judgment of how rough the voice sounds

R: Roughness is a judgement of how irregular and noisy the voice sounds; it should relate to aperiodicity in the vibratory cycle

B: Breathiness is a judgement of how much additional airflow is perceived; it should relate to higher minimum airflow during the glottal cycle

A: Asthenia is a judgement of how weak the voice sounds; it should relate to the sound pressure level of the voice

S: Strain is a judgement of how compressed or hyperfunctional the voice sounds

GRBAS vs. CAPE-V

CAPE-V is more reliable

Whats the difference between GERD and LPR?

GERD is a backflow of stomach contents into the esophagus; LPR is backflow from stomach all the way into the throat (it is aerosolized, essentially a mist of relflux

Muscles of Inspiration

- Diaphragm
– External Intercostals
– Sternocleidomastoids
– Scalenes
– Pectoralis (major and minor)

Muscles of Expiration

-Internal Intercostals
– Rectus Abdominis
– Transverse Abdominis
– Internal Obliques
– External Obliques

Extrinsic LARYNGEAL MUSCLES

• Suprahyoids vs. Infrahyoids
  • Suprahyoid Muscles - Raise the larynx
  – Stylohyoid
  – Mylohyoid
  – Digastrics (anterior and posterior bellies)
  – Geniohyoid

• Infrahyoid Muscles - Lower the hyoid and
  larynx
  – Thyrohyoid
  – Sternothyroid
  – Sternohyoid
  – Omohyoid
  

  
  

Intrinsic Laryngeal Muscles

Five Intrinsic Laryngeal Muscles
• Affect the position, length, and tension of the
vocal folds
– Change position of the cartilage framework that
houses the vocal folds.
– Alter the length, tension, and shape of the vocal
fold edge.
– Change the shape of the glottal opening between
the vocal folds.

intrinsic laryngeal muscles cont

Cricothyroid m. (CT)-Tensor
• Thyroarytenoid m. (TA)-Adductor
• Lateral Cricoarytenoid m. (LCA)-Adductor
• Interarytenoid m.(IA)-Adductor
– Transverse (Horizontal)
– Oblique (Crossed)
• Posterior Cricoarytenoid m. (PCA)-Abductor

Superior Laryngeal Nerve Paralysis (External Branch):

Unilateral

• Unilateral ESLN paralysis = Unilateral Cricothyroid muscle dysfunction.