Vocal cord cyst

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Vocal cord cyst
Vocal Folds.jpg
a) Vocal fold cysts b) Vocal fold cysts with corresponding scars c) Epidermoid cyst

Vocal fold cysts (also known as vocal cord cysts) are benign masses of the membranous vocal folds. [1] These cysts are enclosed, sac-like structures that are typically of a yellow or white colour. [2] They occur unilaterally on the midpoint of the medial edge of the vocal folds. [1] They can also form on the upper/superior, surface of the vocal folds. [1] There are two types of vocal fold cysts: [1]

Contents

  1. Sub-epithelial vocal fold cysts- located in the superficial lamina propria of the vocal folds. [1]
  2. Ligament vocal fold cysts- located within the deeper layers of the lamina propria or on the vocal ligament. [1]

The symptoms of vocal fold cysts vary but most commonly include a hoarse voice and problems with the pitch of the voice. Vocal fold cysts are diagnosed based on gathering a case history, perceptual examination, and laryngeal imaging. [3] Practicing good vocal hygiene is recommended to prevent vocal fold cysts. [4] Initial treatment of the cysts involves voice therapy to reduce harmful vocal behaviours. If symptoms remain after voice therapy, patients may require surgery to remove the cyst. Surgery is typically followed by vocal rest and further voice therapy to improve voice function. Cysts may also be treated using vocal fold steroid injection. [5]

Histology

A cross section of the vocal folds showing the different layers. Cross-section of the vocal fold by Reinke.jpg
A cross section of the vocal folds showing the different layers.

The vocal folds consist of 3 primary layers; the Epithelium, the Lamina Propria (containing superficial, intermediate and deep layers) and the Thyroarytenoid Muscle. Vocal fold cysts commonly appear in the Superficial portion of the Lamina Propria, the cyst size impacts the nature of this layer making it more rigid. The border of vocal fold cysts contains squamous or epithelial cells. In the case of retention cysts, the border consists of glandular epithelium. Epidermoid cysts closely resemble epidermal cysts that can occur anywhere in the body. [6]

Types of vocal cord cysts

Sub-epithelial cysts (also known as mucous retention cysts) are closed lesions that occur from a build-up of tissue on the vocal folds. [2] They are typically found in the middle portion of the upper lamina propria of the vocal folds. [2] Sub-epithelial cysts are small and white in colour. [7] Their presence on the vocal folds usually does not disrupt the vibration of the vocal folds for speech (known as the "mucosal wave"). [2]

Ligament cysts (also known as epidermoid cysts) are closed lesions that occur near the vocal ligament in the deep layers of the lamina propria. [2] Ligament cysts are usually larger in size than sub-epithelial cysts. [7] They are yellow in colour and unlike sub-epithelial cysts, their presence is usually observed to disrupt the mucosal wave of the vocal folds in the region around the cyst. [7]

Signs and symptoms

Sub-epithelial vocal fold cysts and ligament vocal fold cysts are characterized by similar symptoms. [1] The presence and severity of symptoms may be influenced by the location and size of the cyst. [7]

Common symptoms include:

Signs and symptoms of vocal fold cysts may remain stable or increase over time. [1] In rare cases it is also possible for symptoms to improve if the cyst ruptures spontaneously. [1] [5] Symptoms affecting quality of voice tend to worsen after speaking for long periods of time, or when speaking with increased volume. [1] Many individuals who use their voice professionally find even a slight presence of symptoms to be problematic. [1] However, some voice professionals are not impacted by the presence of vocal cysts. [8]

Vocal dynamics

Vocal fold cysts cause the properties of the vocal folds to change. [9] When a cyst is present on a vocal fold, the cover of the vocal fold becomes more stiff and increases in mass. [9] The increased mass and stiffness tends to result in hyperkinetic muscular movement during phonation. [9] Hyperkinetic movement is characterized by increased rigidity in the affected vocal fold(s). [9] This hyperkinetic movement results in the voice being perceived as hoarse. [9] (see Signs and Symptoms) Specifically, the presence of a vocal fold cyst leads to an asynchronous mucosal wave of the vocal folds during phonation. [9]

Causes

There are several possible causes of vocal fold cysts:

  1. They can be congenital. [1]
  2. They can result from the blockage of a mucous gland's excretory duct. [10] In this case, they are sometimes referred to as retention cysts. [10]
  3. They can be the result of phonotrauma. [1] Phonotrauma refers to behaviours that can lead to vocal fold injuries, such as vocal overuse (i.e. too much speaking), vocal misuse (i.e. speaking in an unnaturally high or low pitch), or vocal abuse (i.e. yelling or whispering for prolonged periods). [11] Vocal folds vibrate during phonation resulting in repeated collisions of the right and left vocal folds. [11] Phonotrauma subjects the vocal folds to excessive mechanical forces during these vibratory cycles, which can lead to the development of a wound. [11] It is the healing of these wounds, which leads to tissue re-structuring, that can result in a vocal fold cyst. [11]

Diagnosis

There are generally four components included in the full diagnosis of a vocal cord cyst: a medical and voice history, a head and neck exam, a perceptual assessment of the voice and imaging of the vocal folds. [11] A medical and voice history can help distinguish patterns of misuse and phonotrauma to assist in diagnosis. [3] The primary perceptual sign of vocal fold cysts is hoarseness of the voice. [3] Diagnosis through perceptual means alone is difficult, therefore in the fourth component of diagnosis the patient often undergoes an imaging procedure. [2] [12] Imaging is most commonly done with laryngeal videostroboscopy. [11] A videostroboscopy is an examination of the vocal folds using flashes of light to slow down the image of the vocal fold movement enough to provide a sharp picture of the phases of the movement cycle (mucosal wave.) [13] This procedure provides information about vocal fold vibrations during speech, vocal intensity and vocal frequency. [11] Imaging shows the reduced movement of the vocal folds (mucosal wave) when a vocal fold cyst is present. [11] Further, videostroboscopy tends to show increased submucosal swelling in the affected areas of the vocal fold(s) [9] More recently, other technologies have been introduced to assist with obtaining imaging of the vocal folds, including the use of Narrow-band imaging (NBI.) [12] Narrow-band imaging involves the use of blue and yellow lights to improve the picture quality of an image and accentuate blood vessel visibility. [12] NBI has been found to help improve visual identification of vocal fold cysts in some cases. [12]

Vocal fold cysts can be differentiated from other vocal fold growths as they are usually unilateral. [3] The two types of vocal fold cysts (sub-epithelial and ligament cysts) can be differentiated by colour, size and location. [2] [14] (See section on Types of vocal cord cysts for more information.)

If the vocal fold cyst(s) are presumed to be congenital, the patient should have a history of presenting with a hoarse voice. [9]

Patients with vocal fold cysts are considered for surgery when presenting with: [2]

Prevention

A key aspect of preventing vocal fold cysts is good vocal hygiene. [4] Good vocal hygiene promotes the healthy use of the vocal apparatus and the avoidance of phonotrauma. [4] Good vocal hygiene practices involve the avoidance of: [4]

In addition, good vocal hygiene involves getting enough rest and drinking sufficient water. [4] It is important to keep the vocal fold tissue healthy and hydrated, and when possible to limit the quantity of speaking in order to avoid damage. [4]

Treatment

Vocal fold cysts are treated using a multidisciplinary approach. [15] [16] Vocal fold cysts are most responsive when surgical intervention is supplemented with voice therapy. Applying vocal therapy techniques in isolation has not yet been proven to remediate and decrease the actual size of the vocal fold cyst. [17]

Voice therapy to address harmful vocal behaviours is recommended as the first treatment option. [3] Voice therapy may involve reducing tension in the larynx, reducing loudness, reducing the amount of speech produced, and modifying the environment. [18] If symptoms are significant, treatment usually involves microsurgery to remove the cyst. [3] Although voice therapy is useful for preventing vocal fold cysts caused by phonotrauma and for promoting safe vocal practices, vocal fold cysts tend not to respond to therapy alone and typically require surgery for full repair. [9]

During surgery, attempts are made to preserve as much vocal fold tissue as possible, [3] given that glottal insufficiency (a gap in the vocal folds) is a possible consequence of surgery. [15] Vocal fold tissue can be preserved during surgery by raising a micro-flap, removing the cyst, then laying the flap back down. [15] This is intended to lead to minimal scarring and improved voice function. [15] However, if any epithelium from the cyst sac is left behind during surgery, the cyst may regrow. [8] Surgery of the larynx may also be conducted using a CO2 laser, which was reported as early as the 1970s. [19] Congenital ductal cysts (those caused by blockage of a glandular duct) may be treated by marsupialization. [20]

Following surgery, patients are recommended to take 2 to 14 days of vocal rest. [2] In absolute vocal rest, activities such as talking, whispering, whistling, straining, coughing, and sneezing are restricted. [21] Once adequate healing has occurred, the patient may be transitioned to relative vocal rest, which typically involves 5 to 10 minutes of breathy voicing per hour. [21] Voice therapy is then required to restore as much function as possible. [3] Post-operative voice therapy may include addressing harmful vocal behaviours, exercises to restrengthen the larynx, and reintegration into normal voice activities. [22]

Professional voice users who do not experience substantial limitations due to their cysts may choose to forego surgery. [8] Considering that some cysts remain stable over long periods of time, voice therapy alone may be an option for those who are resistant to surgery. [15] Another option for those who are unwilling to undergo surgery is vocal fold steroid injection (VFSI). [23] Injection of the vocal folds may be done transorally or percutaneously, through the thyrohyoid membrane, thyroid cartilage, or cricothyroid membrane. [23] After VFSI, patients are recommended to take 1 to 7 days of vocal rest. [23] VFSI may also be used to delay surgery, or as a treatment method when the risks associated with surgery are deemed to be too high. [23]

Vocal Fold Cyst and mucosal bridge after dissection Vocal Fold Cyst after dissection.jpg
Vocal Fold Cyst and mucosal bridge after dissection

Prognosis

Following diagnosis, voice therapy should be implemented to optimize vocal hygiene. [3] Vocal fold cysts tend not to improve solely through vocal rest or vocal therapy. [9]

Patients with sub-epithelial cysts have a better prognosis for timely recovery of vocal abilities than patients with ligament vocal fold cysts. [2] Typically, patients can resume speaking activities in 7–30 days following surgery, and singing activities 30–90 days post-surgery. [2]

Up to 20% of patients show scarring, polyps or vascular changes of the vocal folds following surgery. [7] In severe cases, these resulting symptoms may require further surgery. The patient must always be aware of the impact and potential complications of surgery on their voice, especially if the voice is heavily used occupationally. In these cases, post-operative therapy should be discussed.

See also

Related Research Articles

<span class="mw-page-title-main">Otorhinolaryngology</span> Medical specialty of the head and neck

Otorhinolaryngology is a surgical subspecialty within medicine that deals with the surgical and medical management of conditions of the head and neck. Doctors who specialize in this area are called otorhinolaryngologists, otolaryngologists, head and neck surgeons, or ENT surgeons or physicians. Patients seek treatment from an otorhinolaryngologist for diseases of the ear, nose, throat, base of the skull, head, and neck. These commonly include functional diseases that affect the senses and activities of eating, drinking, speaking, breathing, swallowing, and hearing. In addition, ENT surgery encompasses the surgical management of cancers and benign tumors and reconstruction of the head and neck as well as plastic surgery of the face, scalp, and neck.

<span class="mw-page-title-main">Vocal cords</span> Folds of throat tissues that help to create sounds through vocalization

In humans, the vocal cords, also known as vocal folds, are folds of throat tissues that are key in creating sounds through vocalization. The size of vocal cords affects the pitch of voice. Open when breathing and vibrating for speech or singing, the folds are controlled via the recurrent laryngeal branch of the vagus nerve. They are composed of twin infoldings of mucous membrane stretched horizontally, from back to front, across the larynx. They vibrate, modulating the flow of air being expelled from the lungs during phonation.

Vocal cord nodules are bilaterally symmetrical benign white masses that form at the midpoint of the vocal folds. Although diagnosis involves a physical examination of the head and neck, as well as perceptual voice measures, visualization of the vocal nodules via laryngeal endoscopy remains the primary diagnostic method. Vocal fold nodules interfere with the vibratory characteristics of the vocal folds by increasing the mass of the vocal folds and changing the configuration of the vocal fold closure pattern. Due to these changes, the quality of the voice may be affected. As such, the major perceptual signs of vocal fold nodules include vocal hoarseness and breathiness. Other common symptoms include vocal fatigue, soreness or pain lateral to the larynx, and reduced frequency and intensity range. Airflow levels during speech may also be increased. Vocal fold nodules are thought to be the result of vocal fold tissue trauma caused by excessive mechanical stress, including repeated or chronic vocal overuse, abuse, or misuse. Predisposing factors include profession, gender, dehydration, respiratory infection, and other inflammatory factors.

<span class="mw-page-title-main">Reinke's edema</span> Medical condition

Reinke's edema is the swelling of the vocal cords due to fluid (Edema) collected within the Reinke's space. First identified by the German anatomist Friedrich B. Reinke in 1895, the Reinke's space is a gelatinous layer of the vocal cord located underneath the outer cells of the vocal cord. When a person speaks, the Reinke's space vibrates to allow for sound to be produced (phonation). The Reinke's space is sometimes referred to as the superficial lamina propria.

<span class="mw-page-title-main">Laryngitis</span> Inflammation of the larynx (voice box)

Laryngitis is inflammation of the larynx. Symptoms often include a hoarse voice and may include fever, cough, pain in the front of the neck, and trouble swallowing. Typically, these last under two weeks.

<span class="mw-page-title-main">Laryngeal papillomatosis</span> Medical condition

Laryngeal papillomatosis, also known as recurrent respiratory papillomatosis (RRP) or glottal papillomatosis, is a rare medical condition in which benign tumors (papilloma) form along the aerodigestive tract. There are two variants based on the age of onset: juvenile and adult laryngeal papillomatosis. The tumors are caused by human papillomavirus (HPV) infection of the throat. The tumors may lead to narrowing of the airway, which may cause vocal changes or airway obstruction. Laryngeal papillomatosis is initially diagnosed through indirect laryngoscopy upon observation of growths on the larynx and can be confirmed through a biopsy. Treatment for laryngeal papillomatosis aims to remove the papillomas and limit their recurrence. Due to the recurrent nature of the virus, repeated treatments usually are needed. Laryngeal papillomatosis is primarily treated surgically, though supplemental nonsurgical and/or medical treatments may be considered in some cases. The evolution of laryngeal papillomatosis is highly variable. Though total recovery may be observed, it is often persistent despite treatment. The number of new cases of laryngeal papillomatosis cases is approximately 4.3 cases per 100,000 children and 1.8 cases per 100,000 adults annually.

<span class="mw-page-title-main">Bogart–Bacall syndrome</span> Voice disorder caused by abuse or overuse of the vocal cords

Bogart–Bacall syndrome (BBS) is a voice disorder that is caused by abuse or overuse of the vocal cords.

A hoarse voice, also known as dysphonia or hoarseness, is when the voice involuntarily sounds breathy, raspy, or strained, or is softer in volume or lower in pitch. A hoarse voice can be associated with a feeling of unease or scratchiness in the throat. Hoarseness is often a symptom of problems in the vocal folds of the larynx. It may be caused by laryngitis, which in turn may be caused by an upper respiratory infection, a cold, or allergies. Cheering at sporting events, speaking loudly in noisy situations, talking for too long without resting one's voice, singing loudly, or speaking with a voice that is too high or too low can also cause temporary hoarseness. A number of other causes for losing one's voice exist, and treatment is generally by resting the voice and treating the underlying cause. If the cause is misuse or overuse of the voice, drinking plenty of water may alleviate the problems.

Adenomyoma is a tumor (-oma) including components derived from glands (adeno-) and muscle (-my-). It is a type of complex and mixed tumor, and several variants have been described in the medical literature. Uterine adenomyoma, the localized form of uterine adenomyosis, is a tumor composed of endometrial gland tissue and smooth muscle in the myometrium. Adenomyomas containing endometrial glands are also found outside of the uterus, most commonly on the uterine adnexa but can also develop at distant sites outside of the pelvis. Gallbladder adenomyoma, the localized form of adenomyomatosis, is a polypoid tumor in the gallbladder composed of hyperplastic mucosal epithelium and muscularis propria.

<span class="mw-page-title-main">Contact granuloma</span> Medical condition

Contact granuloma is a condition that develops due to persistent tissue irritation in the posterior larynx. Benign granulomas, not to be confused with other types of granulomas, occur on the vocal process of the vocal folds, where the vocal ligament attaches. Signs and symptoms may include hoarseness of the voice, or a sensation of having a lump in the throat, but contact granulomas may also be without symptoms. There are two common causes associated with contact granulomas; the first common cause is sustained periods of increased pressure on the vocal folds, and is commonly seen in people who use their voice excessively, such as singers. Treatment typically includes voice therapy and changes to lifestyle factors. The second common cause of granulomas is gastroesophageal reflux and is controlled primarily through the use of anti-reflux medication. Other associated causes are discussed below.

Vocal cord paresis, also known as recurrent laryngeal nerve paralysis or vocal fold paralysis, is an injury to one or both recurrent laryngeal nerves (RLNs), which control all intrinsic muscles of the larynx except for the cricothyroid muscle. The RLN is important for speaking, breathing and swallowing.

Spasmodic dysphonia, also known as laryngeal dystonia, is a disorder in which the muscles that generate a person's voice go into periods of spasm. This results in breaks or interruptions in the voice, often every few sentences, which can make a person difficult to understand. The person's voice may also sound strained or they may be nearly unable to speak. Onset is often gradual and the condition is lifelong.

Puberphonia is a functional voice disorder that is characterized by the habitual use of a high-pitched voice after puberty, hence why many refer to the disorder as resulting in a 'falsetto' voice. The voice may also be heard as breathy, rough, and lacking in power. The onset of puberphonia usually occurs in adolescence, between the ages of 11 and 15 years, at the same time as changes related to puberty are occurring. This disorder usually occurs in the absence of other communication disorders.

<span class="mw-page-title-main">Laryngopharyngeal reflux</span> Flow of stomach contents into the throat (larynx and pharynx)

Laryngopharyngeal reflux (LPR) or laryngopharyngeal reflux disease (LPRD) is the retrograde flow of gastric contents into the larynx, oropharynx and/or the nasopharynx. LPR causes respiratory symptoms such as cough and wheezing and is often associated with head and neck complaints such as dysphonia, globus pharyngis, and dysphagia. LPR may play a role in other diseases, such as sinusitis, otitis media, and rhinitis, and can be a comorbidity of asthma. While LPR is commonly used interchangeably with gastroesophageal reflux disease (GERD), it presents with a different pathophysiology.

Histology is the study of the minute structure, composition, and function of tissues. Mature human vocal cords are composed of layered structures which are quite different at the histological level.

Laryngeal cysts are cysts involving the larynx or more frequently supraglottic locations, such as epiglottis and vallecula. Usually they do not extend to the thyroid cartilage. They may be present congenitally or may develop eventually due to degenerative cause. They often interfere with phonation.

Endoscopic laser cordectomy, also known as Kashima operation, is an endoscopic laser surgical procedure performed for treating the respiratory difficulty caused as a result of bilateral abductor vocal fold paralysis. Bilateral vocal fold paralysis is basically a result of abnormal nerve input to the laryngeal muscles, resulting in weak or total loss of movement of the laryngeal muscles. Most commonly associated nerve is the vagus nerve or in some cases its distal branch, the recurrent laryngeal nerve. Paralysis of the vocal fold may also result from mechanical breakdown of the cricoarytenoid joint. It was first described in by Kashima in 1989.

Arytenoid adduction is a surgical procedure used to treat vocal cord paralysis. A suture is used to emulate the action of the lateral cricoarytenoid muscle and position the paralyzed vocal cord closer to the midline. This allows the two vocal cords to meet and can improve speaking and swallowing ability for affected patients. Arytenoid adduction is often performed in conjunction with medialization thyroplasty.

Muscle tension dysphonia (MTD) was originally coined in 1983 by Morrison and describes a dysphonia caused by increased muscle tension of the muscles surrounding the voice box: the laryngeal and paralaryngeal muscles. MTD is a unifying diagnosis for a previously poorly categorized disease process. It allows for the diagnosis of dysphonia caused by many different etiologies and can be confirmed by history, physical exam, laryngoscopy and videostroboscopy, a technique that allows for the direct visualization of the larynx, vocal cords, and vocal cord motion.

<span class="mw-page-title-main">Intubation granuloma</span> Medical condition

Intubation granuloma is a benign growth of granulation tissue in the larynx or trachea, which arises from tissue trauma due to endotracheal intubation. This medical condition is described as a common late complication of tracheal intubation, specifically caused by irritation to the mucosal tissue of the airway during insertion or removal of the patient's intubation tube.

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