Voice Disorders Flashcards
Laryngeal skeleton:
1 Bone – hyoid bone
Hyoid membrane
6 Cartilages: Thyroid -Thyroid notch Cricoid Epiglottis - unpaired Arytenoid (2) -Vocal process and muscular process Corniculate (2) Cuneform (2)
Laryngeal Cavities:
Vestibule
Laryngeal ventricle
Glottis
Vocal Folds
Made up of different layers
Outer layer = epithelium
Below the epithelium = lamina propria
- Superficial layer = Reinke’s space
- Intermediate layer – less flexible than Reinke’s space
- Deep layer – less flexible than the first two layers
Below the lamina propria = thyroarytenoid muscle
Cover-Body Model
Cover = epithelium and superior layer of the lamina propria
Loose and pliable; vibrates the most
Vocal ligament = intermediate and deep lamina propria layers
Stiffer
Body = thyroarytenoid muscle
Stiffest
Extrinsic Muscles of the Larynx
Extrinsic – connect to the hyoid bone and a structure outside of the larynx
Divided into suprahyoids and infrahyoids
Suprahyoids- attach above the hyoid bone; contraction elevates the larynx
Infrahyoids- attach below the hyoid bone; contractions depresses the larynx
Intrinsic Muscles of the Larynx
Intrinsic – either abduct or adduct the vocal folds
Abduct – contraction opens the vocal folds
Adduct – contraction closes the vocal folds
Intrinsic Muscles of the Larynx
Intrinsic – either abduct or adduct the vocal folds
Intrinsic muscles – adduction
- Lateral cricoarytenoids (insert into the muscular process)
- Interarytenoid – transverse and oblique
Intrinsic muscles – abduction
-Posterior cricoarytenoid
Tensors – control vocal pitch
-Cricothyroid – pars rectus and pars oblique
Ligaments of the Larynx
Thyroepiglottic ligament
Joints of the Larynx
Cricoarytenoid joints
- Adduction
- Abduction
Cricothyroid joints
- Downward tilt of the thyroid cartilage
- Upwards tilt cricoid cartilage
Laryngeal Innervation
Vagus (not Vegas) X
Divided into three main branches:
Pharyngeal nerve – motor information to some soft palate muscles
Superior laryngeal nerve
Internal – sensory information to larynx
External – motor information to the cricothyroid muscle
Recurrent laryngeal – motor information to all intrinsic muscles of the larynx except cricothyroid
- Right recurrent loops around subclavian artery
- Left recurrent loops around the arch of the aorta (heart) – cardiac problems could cause vocal fold paralysis
Myoelastic-Aerodynamic Theory:
Muscle force - Lateral cricoarytenoid and interarytenoid muscles contract
Tissue elasticity – vocal folds
Air pressures – subglottal pressures
Bernoulli Principle:
Air increases velocity (speed) and decreases in pressure when passing through a narrow channel
This draws the vocal folds medially
Positive air pressure opens the vocal folds and negative air pressure closes the vocal folds
One cycle of vocal fold vibration
Voice Production
Mucosal wave created from vocal fold movement
- Open from bottom to top
- Close from top to bottom
Voiced speech sounds – vocal folds come together and vibrate
Voiceless speech sounds and inhale – vocal folds are apart
Fundamental frequency – rate of vocal fold vibration
-Measured in cycles per second/Hertz
Children 250-300 Hz
Adult females 190-250 Hz
Adult males 180-250 Hz
Pitch & Loudness
Raise pitch:
Vocal folds lengthen, tighten, and increase tension
Lower pitch:
Vocal folds relax, increase mass, and decrease vibration
Increase loudness:
Vocal folds are held together tightly
Subglottal pressure builds, then forcefully blows apart vocal folds
Vocal folds close more forcefully
Infant Larynx
Positioned high in the neck
-Gradually lowers until ~ age 15-20
Smaller
Vocal folds are short
Complex vocal ligament layers emerge around age 3 years
Neurologically immature (coordination improves w/ maturation)
Puberty & Laryngeal Development
Cartilages enlarge
Epiglottis flattens and becomes less bulky
Males- angle of thyroid cartilages decreases (Adam’s apple - thyroid notch becomes more visible)
Males – laryngeal mucosa become stronger and thicker
Vocal folds grow
Pitch lowers
Mature voice ~18 years
Aging & Laryngeal Development
Cartilages ossify – stiffen
Thinning and atrophy of vocal fold muscles
Bowing vocal folds
Reduced lubrication
“Senescent voice”
Tremulous, weak, hoarse, or breathy
Good physical health – good vocal quality
Voice Disorders
Structural disorders – physical changes in the vocal mechanism
E.g., changes in vocal fold tissue and the aging larynx
Neurogenic disorders – problems with CNS or PNS innervation of the larynx – affects vocal functioning
E.g., vocal tremor, spasmodic dysphonia, or vocal fold paralysis
Functional disorders- improper or inefficient use of the vocal mechanism
E.g., vocal fatigue, muscle tension aphonia, ventricular phonation
Overlap is common
Signs & Symptoms of Voice Disorders
Dysphonia – altered pitch, loudness or vocal effort
- Breathiness (puffs of air escape the VF)
- Hoarseness (irregularity in quality)
- Harshness (strained/strangled voice quality; increased tension)
- Tremor (quivering sound)
- Phonation breaks (VF not closing)
Other signs and symptoms:
- Increased vocal effort
- Fatigue
- Excessive cough and/or throat clearing
- Short of breath
Laryngomalacia (luh ring oh muh lay she uh)
Structural VD
Congenital:
- Lack of calcium results in weak cartilage above the glottis; the cartilages may collapse under force of respiration
- Tracheomalacia may also be present (weakness in the carts of the trachea; can also collapse)
- Stridor - noisy breathing (due to floppiness of carts falling into airstream)
- Gastroesophageal reflux
- Surgical intervention may be needed to correct airway obstruction
Laryngeal Web
Structural VD:
Webbing of the glottis
- a thin sheet of connective tissue btwn the VF; can be complete or partial
- VF are unable to seperate
Congenital laryngeal atresia – complete web (more severe)
Surgical intervention
Can have mild to severe effect on voice
Papilloma
Structural VD:
Benign, wart-like growths on the epithelium of the vocal folds
-Spread from vocal folds up; subglottic (into the trachea) considered aggressive
Cause:
Human papilloma virus
Symptoms:
Hoarseness, stridor, aphonia, and respiratory distress
Treatment:
Laser removal and therapy
Can occur in both children and adults; more severe in children bc the larynx smaller
Subglottic Stenosis
Structural VD: Can be congenital or acquired -Accident or surgical trauma -GERD -Radiation therapy
Narrowing of the larynx below the vocal folds:
- Thickened cartilage and/or tissue
- Varying degrees
Treatment:
Laser therapy to remove excess tissue or cartilage or reconstruction
Rheumatoid Arthritis (RA)
Structural VD:
- Inflammation in multiple joints
- Etiology unknown – commonly seen in thirties and forties
- Cricoarytenoid joint can develop RA
Symptoms:
Hoarseness, pain in the ear when swallowing (due to nerve innervation), labored breathing, stridor, globus sensation in throat
Joints may become fixed or immobile – airway compromise
Treatment – cool humidification, anti-inflammatories, steroids
Laryngeal Trauma
Structural VD:
Blunt injury to the neck or injury to the larynx
-Damage to cricoarytenoid joint and/or arytenoid cartilages
-Can result in fibrosis (scarring)
Symptoms: hoarseness, dyspnea, and dysphagia
Without fibrosis, can exhibit full recovery
Sulcus Vocalis
Structural VD
Bowing of the vocal folds (spindle shaped gap) caused by the development of a groove
-Usually bilateral
-Cause – unknown
Symptoms: dysphonic
Vocal Fold Paralysis
Neurogenic VD:
Unilateral or bilateral; abduction or adduction
-Pharyngeal nerve damage = hypernasality
-Recurrent laryngeal nerve damage = abduction and adduction affected
-Superior laryngeal nerve damage = problems with pitch
Potential causes: Trauma Progressive diseases Viral infection Heart problems* (may be unknown to client) Idiopathic
Spasmodic Dysphonia
Abnormal involuntary movements of one or muscles of the larynx
Action induced and task specific
Vocal fold movement is strained
Voice is strained, jerky, tight, or hoarse
May have periods of aphonia or spasms
Causes:
Historically thought to be psychogenic
Neurogenic – focal dystonia of the larynx
Adductor SD
Most common; intermittent, tight adduction of the vocal folds
Symptoms:
- Strained, forced voicing
- Intermittent aphonia or voice breaks
- Stutter-like phonatory blocks and delayed onset of phonation
- Vocal tremor
- Monoloudness and/or intermittent bursts of loudness
- Monopitch
Mixed SD
Because it’s never simple!
Combination of adductor and abductor
Strained vocal quality with breathy breaks
Primarily adductor or abductor
Abductor SD
Normal or breathy voice quality with involuntary period of aphonia
Vocal fold spasms in the abducted position
Aphonia triggered by voiceless consonants
Symptoms: Vocal tremor Reduced speech intelligibility Monoloudness Hyperventilation
Nodules
Benign growths on the epithelium
Usually bilateral
Occur where vibration is most vigorous
Vascular and pliable and then hard and fibrous
Symptoms: low pitch, hoarseness, and breathiness
Polyp
Benign tumors of the mucosa
Unilateral, soft and pliable
Caused by abuse and other issues like allergies
Symptoms: low pitch, hoarseness, and breathiness
Contact Ulcer
Mucosal covering of the tip of the vocal process erodes
Granulation tissue can develop around the ulcer
Causes: misuse of voice – loud at low pitch or GERD or intubation trauma
Symptoms:
Pain which can radiate to ear
Breathy and hoarse
Assessment of Voice Disorders
Team approach
Members: Otolaryngologist, SLP, singing teacher, neurology, and others
SLP’s role: Evaluate vocal symptoms, determine severity, diagnose, and improve vocal function Know when to refer and who to refer to Counseling Advocate
Screening:
- Evaluate respiration, phonation, and resonance
- Formal or informal screening tasks or questionnaires
Comprehensive Assessment:
- Case history
- Oral mechanism exam
- Auditory-Perceptual assessment
- Acoustic assessment
- Aerodynamic assessment
- Imaging
