What Are Voice Disorders

Introduction 

Definition of voice disorders 

Voice disorders are a range of conditions that affect the larynx, which can cause changes to the voice, such as the way the voice sounds. It is important to understand voice disorders as they can be very uncomfortable and affect the daily lives of some people. 

Understanding the human voice 

The vocal system 

   1. Anatomy of the vocal tract 

The vocal tract is a container of air that starts from the top of the vocal folds and goes to the edge of the lips. This consists of resonators, which give the personal quality to individual voices, and modifiers which change sounds into voiced sounds. 

   2. Role of vocal cords 

The vocal cords have different functions, such as protecting the airway from choking, regulating the flow of air into the lungs and producing sounds into speech. 

How voice production works 

   1. Phonation process 

The phonation process is when air is expelled from the lungs through the glottis, which is the opening between the vocal folds in the larynx, creating a pressure drop across the larynx, if the drop is large, the vocal folds start to oscillate.¹ 

   2. Resonance and articulation 

The resonance of the voice is when a voiced sound is amplified and modified by the vocal tract resonators; this produces an Individual distinct voice, whereas articulation is the production of speech. 

Types of voice disorders 

Functional voice disorders 

Functional voice disorders are caused by insufficient or improper use of the phonation without any anatomical or neurological abnormalities. 

1. Vocal nodules 

Vocal nodules can develop from using your voice for a long period, which can cause your voice to sound hoarse. These nodules are small and benign and will usually go away with resting the voice.² 

1. Polyps 

Sometimes, vocal nodules can develop into polyps, which are non-cancerous bumps on the vocal cord; this can occur for reasons of overusing or misusing your voice, such as yelling or smoking cigarettes for a long time. ³ 

1. Vocal cord paralysis 

Vocal cord paralysis is a condition in which you can't control the movement of the muscles that control your voice. This can occur when the nerve impulses to the larynx are disrupted, causing the vocal cords to not move. This results in difficulty in speaking and sometimes can affect breathing because the vocal cords may be too close together.⁴ 

Organic voice disorders 

Organic voice disorders result from physical or structural changes in the anatomy of the vocal nodules or larynx.  

1. Laryngeal cancer 

Laryngeal cancer is a type of cancer that causes cancer cells to form in the tissue of the larynx. This can happen because of the use of cigarettes or drinking too much alcohol. This will lead to symptoms of sore throat causing hoarseness of the voice and ear pain.⁵ 

1. Vocal fold cysts 

If a gland in the vocal cord gets blocked or if debris gets trapped in the vocal tissues, vocal cord cysts, which are benign lesions where fluid can gather, can form. This is different to vocal nodules as it is not linked to voice misuse or overuse. 

1. Granulomas 

A vocal cord granuloma grows on the cartilage that attaches to the back of the vocal cords because of irritation. This can cause pain in the throat when coughing or swallowing.  

Neurogenic voice disorders 

1. Spasmodic dysphonia 

Spasmodic dysphonia is a disorder that can affect the voice and speech through excessive contraction of the laryngeal muscles.⁶ It is a condition that may be lifelong for some people but temporary for others, where it can come and go. There is no cure for it, but symptoms can be improved with treatments and voice therapy. 

1. Parkinson's disease-related voice disorders 

For patients who have been diagnosed with Parkinson’s disease, it is common to see changes in the voice. Patients will have uncertain articulation and a quieter voice due to vocal fold bowing; this can be caused by dopaminergic and non-dopaminergic mechanisms. 

Psychogenic voice disorders 

Sometimes, voice disorders can be associated with emotional distress, which will be categorised as psychogenic voice disorders. There is no structural reason for this, but a person may have a sudden voice loss. 

1. Conversion disorder 

Conversion disorder is a mental health condition that can cause physical symptoms that affect sensory or motor function. This weakness and paralysis have an effect on hearing and causes difficulty in swallowing and speaking. As this is a psychiatric condition, treatment focuses on psychotherapy and cognitive behavioural therapy. 

1. Muscle tension dysphonia 

This is a common voice disorder that occurs when the muscles around the larynx are tight when speaking, so the voice box does not work as efficiently, may sound hoarse, and cause pain.  This can be treated with voice therapy to reduce the tension in the throat. 

Causes and risk factors 

Common causes 

   1. Overuse and misuse of the voice 

Overuse and misuse of the voice causes strain and will harm the vocal cords. This can happen due to talking too much or talking loudly and from persistent coughing. 

1. Smoking and environmental factors 

Smokers often have changes in the voice over time, causing irritation and inflammation to the vocal cords. Their voice will be hoarse and have a lower pitch with a rough quality. They may often be breathless and may take breaks in between talking.  

1. Neurological conditions 

There are many neurologic conditions that can cause voice disorders, such as Parkinson's and multiple sclerosis, as these conditions can affect the nerves that control the vocal cords. 

1. Psychological factors 

A psychological trauma may lead to psychogenic voice disorders. An example of this is that facing a distressing situation may cause a person to lower their voice and speak in a more flat and monotone voice.  

Risk factors 

1. Occupation 

Certain occupations where the voice is used for a prolonged time can have short-term symptoms such as soreness and hoarseness. People who work as teachers or singers use their voices a lot and may have to be loud, too, so they are more at risk of developing vocal disorders. 

1. Age 

As age increases, the vocal fold muscles can weaken and lose muscle mass, making it harder to speak. This is why many old people may have reduced volume and projection of their voices. 

1. Gender 

 Research also shows that there are gender-related differences in the prevalence of voice disorders. As the percentage of females with voice disorders was higher than in males.⁷ This was supported by another study that found that women have more vocal health problems than men, regardless of their jobs.⁸ 

Symptoms of voice disorders 

There is a range of symptoms that is common in all voice disorders. These are: 

• Hoarseness 

Hoarseness is mostly found because of inflammation of the larynx and can be seen in most patients with voice disorders. 

• Pain or discomfort 

Many voice disorders will lead to pain when speaking due to the formation of bumps and inflammation. 

• Changes in pitch or volume 

Voice disorders will lead to an individual's voice sounding higher or lower compared to usual; this can be because of the formation of cysts and polyps. 

• Voice fatigue 

A misuse of the vocal cords will cause tension in the muscles, which will lead to voice fatigue, a person with this will show an increase in phonatory effort over time, which can lead to a decrease in phonatory function.⁹ 

Diagnosis of voice disorders 

1. Medical history and physical examination 

Most healthcare practitioners will start with a medical history to gather any background information to identify the cause and symptoms of the voice disorder. 

1. Voice assessment 

A voice assessment can be done by a speech and language therapist to identify the cause and symptoms of a voice disorder. This is common for the assessment of most voice disorders, such as vocal nodules, polyps or vocal cord paralysis. 

1. Imaging and scoping procedures 

This method involves using X-rays and MRI scans to see growths such as cysts in the throat. Another technique is called stroboscopy, a test that uses a strobe light and video camera to see the vibrations of the vocal cord during speech. 

Treatment and management 

Behavioural therapy and voice hygiene 

Behavioural therapy for voice disorders includes a speech-language pathologist going through exercises that correct the behaviours that may have caused the voice problems.  

Medications 

The most common form of medication for voice disorders is the use of botulin toxin (Botox) injections to relax the tight muscles of the voice box. 

Surgery 

In the case of growths found in vocal nodules and polyps, laser treatments such as carbon dioxide laser surgery can be used to remove the growth. Another type of surgical treatment is phono microsurgery, which uses microsurgical instruments to improve vocal function and breathing. 

Prevention 

Vocal hygiene 

It is important to maintain vocal hygiene to prevent the occurrence of voice disorders. This includes drinking water and reducing the intake of sugary drinks, coffee and alcohol. Drinking warm, non-caffeinated liquids is also soothing, so it can help with increasing vocal hygiene. 

Avoiding risky behaviours 

A person should avoid behaviours that may show improper use of the voice, such as shouting, screaming, singing loudly or smoking. 

Living with a voice disorder 

Living with a voice disorder can be very uncomfortable and distressing. Therefore, coping strategies can be used to improve the quality of life for an individual with a voice disorder.¹⁰ This can include finding support groups, such as The Lary Project, to help with understanding the disorder.  

Conclusion 

There are a range of voice disorders that can cause symptoms such as pain and hoarseness, which may cause disturbance in a person's daily lives, which can also be associated with other neurological or psychological conditions. For this reason, it is important to understand the disorder to help manage and treat symptoms. It is also important to maintain vocal hygiene so that it is less likely for voice disorders to occur.