Neurogenic Voice Disorders

1. Neurogenic Voice Disorders -neurological structures and processes that must function in coordinated balance to produce what we perceptually consider as normal voice -changes in speech can be the first or only manifestation of neurogenic disease-neurological structures and processes that must function in coordinated balance to produce what we perceptually consider as normal voice -changes in speech can be the first or only manifestation of neurogenic disease

2. Neurologic Supply X (Vagus) innervates larynx peripherally Superior laryngeal nerve Internal branch- inserts through thyrohyoid membrane, superior to the vocal folds, provides all sensory information to the larynx External branch- motor nerve to cricothyroid Recurrent laryngeal Loops through the heart before coming back up to the larynx Supplies all sensory information below the vocal folds Motor innervation to posterior cricoarytenoid, thyroarytenoid, lateral cricoarytenoid, and interarytenoid muscles.

4. Neurogenic Voice Disorders Caused by disruption to the neural supply to the larynx Include: Vocal fold paralysis Spasmodic dysphonia Organic Voice Tremor (Essential Tremor)

5. Vocal Fold Paralysis May be bilateral or unilateral May be caused by peripheral involvement of the recurrent laryngeal nerve or the superior laryngeal nerve Possible causes: Surgery Neurological disease Head/neck trauma Viral infections Tumors May affect adductor or abductor muscles Recurrent laryngeal nerve more commonRecurrent laryngeal nerve more common

6. Vocal Fold Paralysis (cont�d) Symptoms: Breathiness Low intensity Low pitch Intermittent diplophonia Result from irregular and incomplete valving of the pulmonary airstream through the glottis during the production of soundResult from irregular and incomplete valving of the pulmonary airstream through the glottis during the production of sound

7. Bilateral Abductor Paralysis Paralyzed in the closed position, cannot abduct sufficiently for respiration Critical condition that requires surgical establishment of airway Sometimes remove arytenoid or suture it in an open position

8. Bilateral adductor paralysis Both folds are in a paramedian position Airway protection is an important issue May require tube feedings Vocal quality: Very dysphonic Breathy Weak Treatment: amplifier or electrolarynx

9. Unilateral abductor paralysis Paralyzed fold remains at midline Airway protection remains intact Voice quality: mildly dysphonic with possible difficulty elevating loudness levels Usually no difficulty with airway; however, may demonstrate stridor upon inhalation

10. Unilateral adductor paralysis Most common type Vocal fold usually in a paramedian position Affected fold fails to adduct to midline Vocal quality: vary depending on position of cord and size of glottal gap during phonation Dependent on the position (how far away from midline) of the affected cord and if there is a vertical level differenceDependent on the position (how far away from midline) of the affected cord and if there is a vertical level difference

11. Superior laryngeal nerve paralysis Less frequent than recurrent laryngeal nerve paralysis Usually unilateral May result in oblique positioning (overlap) of the folds Cricothyroid unable to significantly stretch the vocal folds Vocal quality: Loss of pitch range Vocal fatigue May develop hyperactive compensatory behaviors -thyroid disease and thyroid surgeries Difficult to ascertain Vocal folds lack tone and will not lengthen sufficiently during attempts to change pitch-thyroid disease and thyroid surgeries Difficult to ascertain Vocal folds lack tone and will not lengthen sufficiently during attempts to change pitch

12. Spasmodic Dysphonia Uncertain etiology; describes a family of symptoms Neurologic origin: Focal dystonia resulting from disruption in the extrapyramidal supply from the central nervous system Symptoms: strained, strangled, and effortful voice production Characterized by involuntary adductor or abductor spasms that occur during phonation Women more frequent than men Onset typically between the ages of 40-60

13. Adductor Spasmodic Dysphonia More common Vocal quality: Pressed Strained Strangled Effortful Involuntary adductor spasms during phonation Normal vocal fold structure Intermittent periods of normal phonation may occur

14. Abductor Spasmodic Dysphonia Involuntary abductor spasms during phonation Vocal quality: Intermittently breathy with phonation breaks and short periods of aphonia Folds appear normal Intermittent normal periods of phonation

15. Spasmodic Dysphonia Undisrupted singing, laughing, coughing, throat clearing, humming Stress and increased speaking demands may exacerbate symptoms Treatment: BOTOX injections More effective for adductor type than for abductor typeMore effective for adductor type than for abductor type

16. Organic Voice Tremor Essential tremor: central nervous system disorder that results in involuntary, regular tremors in the limbs, head, larynx, or other oral structures When localized to the larynx- Organic Voice Tremor Gradual onset; typically between ages 40-60 More frequent in males than females May be hereditary

17. Organic Voice Tremor (cont�d) Symptoms: Regular modulating tremor of pitch and intensity when producing pitches ranging from 4Hz to 7Hz, discernable during vowel prolongation �shaky� or �woblly� voice Periodic voice breaks with severe forms Treatment: ??? Limited success with BOTOX

18. Neurological Voice Disorders Related to CNS Disease Affect multiple neuromuscular systems Examples: Myasthenia Gravis Gullain-Barre� Parkinson�s Disease Huntington�s Disease ALS Mutliple Sclerosis Traumatic Brain Injury Group activity: Each group describes vocal quality, symptoms, and treatment for each diseaseGroup activity: Each group describes vocal quality, symptoms, and treatment for each disease