Overview

How our voice is produced 

The voice is the sound produced when the air is forced out of the lung and passes between the vocal cords of the larynx (voice box), the vibration of these vocal cords produces sounds we call voice, which are shaped to produce speech.¹

What are voice disorders?

A voice disorder is defined as any deviation affecting the voice that adversely affects the speaker or the listener, interfering with communication. This deviation could affect the pitch, loudness, or quality of the voice.² 

Role of speech therapy in managing voice disorders

Speech therapy can help people with difficulty speaking to communicate better. Speech-language pathologists (SPLs) are experts in communication, and they can help in the treatment of many types of problems with communication and swallowing, including problems with voice (voice pitch, loudness, and quality), which is the core of voice disorders.⁴

What are the types of voice disorders³

Functional voice disorders

This results when there is an inefficient use of the vocal mechanism despite the normal physical structure.

Organic Voice Disorders (physiological voice disorders) 

Results from changes affecting the voice production mechanism, in its respiratory, laryngeal, or vocal tract part. Organic voice disorders are further classified into structural and neurogenic.

Psychogenic voice disorders  

Other disorders affect the laryngeal mechanism but are not classified as voice disorders, such as

• Paradoxical vocal fold movement (PVFM): when there is an abnormal movement of vocal folds that cause them to come closer and interfere with breathing
• Exercise-induced laryngeal obstruction (EILO): there is an inappropriate movement of vocal cords that causes them to come close and cause airway obstruction during exercise

What causes voice disorders 

As normal voice production involves integration in the function of more than one part of the body, including the respiratory system, the larynx, and ascending above to the pharynx, nasal and oral cavities.

Disrupting one of these systems or the coordination between them may lead to a voice disorder. Disruptions can be organic, functional, or psychogenic. 

Organic causes

Structural 

• Vocal fold lesion
• Larynx inflammation
• Larynx trauma 

Neurogenic

• Paralysis of the nerve supplying the larynx (recurrent laryngeal nerve)
• Spasmodic dysphonia of larynx muscle 
• Parkinson’s disease
• Multiple sclerosis 

Functional causes 

Trauma

• Yelling and screaming
• Excessive throat clearing and coughing 
• Speaking in too high or too low pitch 

Muscle tension dysphonia

Voice fatigue

Psychogenic causes

Chronic stress and anxiety 

Depression

What are the risk factors for voice disorders 

Smoking, alcohol, certain occupation, teacher, singers, reflux laryngitis (GERD), hypothyroidism

There are special conditions that are unique in children to be considered, such as 

• Laryngomalacia: this is a congenital condition that causes the baby’s voice box (larynx) to be softer than normal
• Laryngeal webbing: which is the presence of an abnormal tissue in the voice box (larynx) 
• Laryngeal cleft: this is a congenital abnormality causing an abnormal opening between the voice box (larynx) and the oesophagus³
• Puberphonia: a functional voice disorder in male adolescents following the voice change of puberty³

How We Diagnose Voice Disorders 

Initial evaluation of signs and symptoms³ 

The term “dysphonia” is used to describe the symptoms of altered voice quality, pitch, or loudness, either as an increase or decrease in these characters. 

Symptoms associated with dysphonia include

• rough voice 
• abnormal pitch 
• strained quality of voice
• breathy quality of voice
• abnormal loudness 

Objective measures

• Assessment of breathing pattern 
• Assessment of voice quality 
• Laryngeal imaging with a video endoscopy to visualize the vocal cords' structure, function and vibration during speech
• Acoustic assessment using () to objectively assess voice characters
• Aerodynamic assessment using () to measure parameters related to airflow during speech

What is the role of speech therapy techniques in managing voice disorders

There are a variety of speech therapy techniques that can be considered according to the underlying disorder, therefore, identification of the underlying cause of voice abnormality is the essential initial step to guide the management.⁵ 

Voice therapy is most effective in treating the most common cause of voice disorders: voice misuse. 

Vocal hygiene 

Lifestyle modifications

• Hydration: drinking plenty of water, especially when exercising 
• Using an air humidifier at home 
• Avoiding smoking as it irritates the vocal cords 
• Avoiding spicy food as it causes stomach acid to flow back to the throat and causes irritation⁶

Voice rest 

• Taking vocal naps: resting the voice throughout the day
• Trying not to overuse the voice, especially when hoarse or tired 
• Avoiding using the extremes of vocal range (screaming or whispering) 
• When singing or talking, practice good breathing techniques by supporting your voice with deep breaths from the chest⁶

Vocal Function Exercises

Structured exercises to strengthen and coordinate muscles of the larynx, Outcome studies have found that vocal function exercises are effective in enhancing vocal function in individuals with normal voices and in patients with disordered voices⁷ 

Vocal function exercises include 

• Upright posture
• Abdominal breathing (through nose or mouth) 
• Practice sounds softly yet with full vibration by starting with soft sound 
• Start lightly⁸

Specialized interventions for specific disorders

According to the underlying cause, a combination of speech therapy with medical or surgical approaches may be required 

• Spasmodic dysphonia: injection botulinum toxin (Botox) in addition to voice therapy
• Neurological voice disorders: medical treatment  (e.g., for Parkinson's) along with speech therapy
• Treatment of return of stomach acid to the throat (in cases of Gastroesophageal reflux disease–GERD)
• Treatment of thyroid gland abnormality if present 

Screening for voice disorders 

Screening for the presence of voice disorder is conducted when a voice disorder is suspected based on individuals, or healthcare providers’s concerns. Screening includes evaluation of voice characters, if an abnormality is detected, more evaluation is indicated. 

Summary

•  Summary of the role and benefits of speech therapy in treating voice disorders
• Emphasis on the individualized nature of treatment plans
• Encouragement of early intervention for better outcomes

References