Voice disorders/resonance disorders​

A voice disorder occurs when voice quality, pitch, and loudness differ or are inappropriate for an individual's age, gender, cultural background, or geographic location.

A number of different systems are used for classifying voice disorders. For the purposes of this document, voice disorders are categorized as follows:
  • Organic — voice disorders that are physiological in nature and result from alterations in respiratory, laryngeal, or vocal tract mechanisms
  • Structural — organic voice disorders that result from physical changes in the voice mechanism (e.g., alterations in vocal fold tissues such as edema or vocal nodules; structural changes in the larynx due to aging)
  • Neurogenic — organic voice disorders that result from problems with the central or peripheral nervous system innervation to the larynx that affect functioning of the vocal mechanism (e.g., vocal tremor, spasmodic dysphonia, or paralysis of vocal folds)
  • Functional — voice disorders that result from improper or inefficient use of the vocal mechanism when the physical structure is normal (e.g., vocal fatigue; muscle tension dysphonia or aphonia; diplophonia; ventricular phonation).

Voice quality can also be affected when psychological stressors lead to habitual, maladaptive aphonia or dysphonia. The resulting voice disorders are referred to as psychogenic voice disorders or psychogenic conversion aphonia/dysphonia (Stemple, Glaze, & Klaben, 2010). These voice disorders are rare. SLPs refer individuals suspected of having a psychogenic voice disorder to other appropriate professionals (e.g., psychologist or psychiatrist) for diagnosis and may collaborate in subsequent treatment.

The generic term dysphonia encompasses the auditory-perceptual symptoms of voice disorders. Dysphonia is characterized by altered vocal quality, pitch, loudness, or vocal effort.

Signs and symptoms of dysphonia include
  • roughness (perception of aberrant vocal fold vibration);
  • breathiness (perception of audible air escape in the sound signal or bursts of breathiness);
  • strained quality (perception of increased effort; tense or harsh as if talking and lifting at the same time);
  • strangled quality (as if talking with breath held);
  • abnormal pitch (too high, too low, pitch breaks, decreased pitch range);
  • abnormal loudness/volume (too high, too low, decreased range, unsteady volume);
  • abnormal resonance (hypernasal, hyponasal, cul de sac resonance);
  • aphonia (loss of voice);
  • phonation breaks;
  • asthenia (weak voice);
  • gurgly/wet sounding voice;
  • hoarse voice (raspy, audible aperiodicity in sound);
  • pulsed voice (fry register, audible creaks or pulses in sound);
  • shrill voice (high, piercing sound, as if stifling a scream); and
  • tremulous voice (shaky voice; rhythmic pitch and loudness undulations).
  • Other signs and symptoms include
  • increased vocal effort associated with speaking;
  • decreased vocal endurance or onset of fatigue with prolonged voice use;
  • variable vocal quality throughout the day or during speaking;
  • running out of breath quickly;
  • frequent coughing or throat clearing (may worsen with increased voice use); and
  • excessive throat or laryngeal tension/pain/tenderness.

Signs and symptoms can occur in isolation or in combination. As treatment progresses, some may dissipate, and others may emerge as compensatory strategies are eliminated.
 
Causes
Normal voice production depends on power and airflow supplied by the respiratory system; laryngeal muscle strength, balance, coordination, and stamina; and coordination among these and the supraglottic resonatory structures (pharynx, oral cavity, nasal cavity).

A disturbance in one of the three subsystems of voice production (i.e., respiratory, laryngeal, and subglottal vocal tract) or in the physiological balance among the systems may lead to a voice disturbance. Disruptions can be due to organic, functional, and/or psychogenic causes.

Organic causes include the following:
  • Structural
  • Vocal fold abnormalities (e.g., vocal nodules, edema, glottal stenosis, recurrent respiratory papilloma, sarcopenia [muscle atrophy associated with aging])
  • Inflammation of the larynx (e.g., arthritis of the cricoarytenoid or cricothyroid, laryngitis, laryngopharyngeal reflux)
  • Trauma to the larynx (e.g., from intubation, chemical exposure, or external trauma)
  • Neurologic
  • Recurrent laryngeal nerve paralysis
  • Adductor/abductor spasmodic dysphonia
  • Parkinson's disease
  • Multiple sclerosis
  • Functional causes include the following:
  • Phonotrauma (e.g., yelling, screaming, excessive throat-clearing)
  • Muscle tension dysphonia
  • Ventricular phonation
  • Vocal fatigue (e.g., due to effort or overuse)
  • Psychogenic causes include the following:
  • Chronic stress disorders
  • Anxiety
  • Depression
  • Conversion reaction (e.g., conversion aphonia and dysphonia)
 
Treatment
There are two broad categories: physiologic voice therapy (i.e., those treatments that directly modify the physiology of the vocal mechanism) and symptomatic voice therapy (i.e., those treatments aimed at modifying deviant vocal symptoms or perceptual voice components using a variety of facilitating techniques).

Information taken from ASHA.org

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