The vibratory surface of the human vocal fold is a complex layered structure. Repeat trauma from vocal misuse or overuse may lead to the development of benign lesions that arise primarily within the lamina propria of the vocal fold, also known as the Reinke space.
Benign laryngeal disorders resulting in dysphonia most commonly affect glottic closure and the vibratory characteristics of the true vocal fold. A cyst is defined as an epithelial-lined structure with separate internal contents. Two types of cysts are found within Reinke space, mucus retention cysts and epidermoid cysts.
Application of current knowledge of the anatomy and physiology of the larynx and an understanding of voice production are essential to developing sound surgical approaches for benign laryngeal disorders.
An image depicting an intracordal cyst can be seen below.
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Indirect laryngoscopy of an intracordal cyst is shown. Note the appearance is similar to that of a nodule or polyp.
Two types of cysts are found within Reinke space. Mucus retention cysts are often translucent and are lined with cuboidal or columnar epithelium. Epidermoid cysts contain epithelium or accumulated keratin. These lesions may be true epithelial-lined cysts or pseudocysts. The term intracordal refers to a location just below the cover of the vocal fold within Reinke space and outside of the vocalis muscle.
The prevalence of intracordal lesions in the general population is not known. The group of patients that present to a voice clinic features a high percentage of professional voice users and may not be representative of the general population.
Epidermoid cysts may occur secondary to vocal abuse and overuse or may be secondary to a remnant of epithelium trapped within the lamina propria.[1] Mucus retention cysts may occur spontaneously or may be associated with poor vocal hygiene. They are presumed to arise from an obstructed mucus-producing gland. As the cyst enlarges, it can start to significantly affect the vibratory region of the vocal fold.
A study by Hanshew et al suggested that Streptococcus pseudopneumoniae and, possibly, Pseudomonas, may play a role in the etiology of benign vocal fold lesions, such as cysts, nodules, polyps, and Reinke edema. The investigators found the bacterial communities of 31 out of 44 such lesions to be dominated by S pseudopneumoniae, unlike the microbiota found in healthy saliva and throat samples. Twelve of the remaining 13 lesions contained Pseudomonas, which was not seen in the healthy samples.[2]
Repeated trauma from vocal misuse or overuse may lead to the development of vocal fold nodules, polyps, or cysts. Mucus retention cysts may occur secondary to ductal obstruction, and epidermoid cysts may occur from congenital cell rests or from healing injured mucosa. A focal thickening may also form as a reaction to trauma caused by the cyst on the contralateral cord. Benign lesions are found within the lamina propria and cause dysphonia by disrupting the vibratory pattern and close approximation of the true vocal folds.
A broad spectrum of clinical presentations exists. Patients may report hoarseness, increased effort, fatigue, pain, and soreness with voice use. Singers commonly report abrupt loss of voice or break at a certain pitch. Generally, patients with intracordal lesions have dysphonia that becomes more severe with use. They may also describe periods of aphonia following vocal overuse. Sometimes a vocal fold cyst can affect only the singing voice and not the speaking voice or have little or no effect on voice quality. In the latter situation, no indication exists for treatment. However, for a patient to have a normal speaking and singing voice is not unusual, and a patient may be able to perform. When a patient reports complete aphonia, a significant functional component can be expected. Cysts rarely cause symptoms of stridor, aspiration, globus sensation, or dysphagia.
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This patient had an essentially normal speaking voice but complained of fatigue and loss of vocal range. Note the translucent quality of the mucosal c....
Patients may be hoarse or may have normal speaking voices. Patients in the latter group often exhibit difficulty with the singing voice, including decreased range, easy fatigability, strain, and periods of aphonia associated with heavy voice use. Diplophonia, or the production of two simultaneous tones, is also observed at higher pitches. Singers may exhibit an abrupt break at a specific frequency. In addition, maladaptive compensation patterns may be present (secondary muscle tension dysphonia).
On indirect laryngoscopy, a cyst may appear as a fullness in the fold or simply as a lucent outline visible under the mucosal cover. An intracordal mass must be suspected in a dysphonic patient when no obvious lesion is found on indirect laryngoscopy. Video stroboscopy is essential to making the diagnosis of a cyst. The mucosal wave overlying the cyst is decreased or absent in comparison with the opposite cord.
View Image
Indirect laryngoscopy of an intracordal cyst is shown. Note the appearance is similar to that of a nodule or polyp.
View Image
Note the translucent outline of the body of the cyst within the mucosal cover of the right true vocal fold. The articulatory surface of the cord is mi....
Surgery is reserved for patients with lesions that demonstrate no significant vocal symptom reversibility with exhaustive medical and speech therapy or for patients in whom the diagnosis is uncertain. Medical therapy consists of reversing or eliminating irritants and inflammatory conditions such as allergy and reflux laryngitis and maintaining good vocal hygiene. Speech therapy consists of reducing abusive behaviors, improving vocal efficiency, and modifying vocal habits to maximize rest and recovery time (see the Medscape Reference article Voice Therapy).
In singers, surgery is indicated when the accustomed performance style or required schedule cannot be maintained, for recurrent disabling periods of dysphonia, or for intolerable vocal strain and fatigue. These requirements must be assessed on an individual basis since some performers are able to sing infrequently enough to prevent significant problems.
The vocal fold is composed of a muscle covered by a free mucosal edge that vibrates and can be separated into discrete layers in which various types of pathology may develop. Each layer has distinct mechanical properties and can be differentiated by the concentration of elastin and collagen fibers in a 3-dimensional layered structure parallel to the leading edge.
Histologically, the vocal fold is a complex structure. The delicate arrangement of the extracellular matrix proteins within the lamina propria permits passive movement of the epithelium, or vocal cover, over the body, resulting in the formation of the mucosal wave as air is passed through the glottis as a release of building subglottic pressure. Most benign lesions occur in the superficial layer of the lamina propria; therefore, surgical approaches to benign lesions should ideally be confined to this layer. Benign lesions are usually superficial to the vocal ligament and the thyroarytenoid muscle.
Videostroboscopy is essential in making the diagnosis of a cyst. The mucosal wave overlying the cyst is decreased or absent in comparison with the opposite vocal fold because the cyst tethers the mucosa, altering the biomechanical properties of the lamina propria and preventing mucosal wave propagation. Nodules and polyps, which are contained entirely within the superficial layers of the lamina propria, usually do not severely hamper mucosal wave propagation (see Vocal Polyps and Nodules).
Despite the excellent visualization provided by videostroboscopy, it cannot replace direct laryngoscopy and palpation of the lesion as the criterion standard in diagnosis and should not be considered a substitute, especially in patients in whom a neoplastic process is possible.
The key to identifying intracordal cysts is minimizing surrounding edema and inflammation. Modified voice use, vocal hygiene, and, often, medication aid in accomplishing reduced edema and inflammation. Thus, the subtle stroboscopic appearance of a significant intracordal cyst may be revealed. Patients may be placed on a 2-week period of vocal rest, perhaps accompanied by a high-dose corticosteroid taper. Steroid treatment reduces the overlying and sometimes camouflaging inflammation and swelling while leaving the cyst unchanged, thus making its diagnosis easier.
Evaluating and treating any intercurrent medical conditions affecting the voice (eg, reflux laryngitis, allergic rhinitis) are also essential. In addition, patients with vocal fold cysts often have compounding functional issues that need to be addressed, both preoperatively and postoperatively, with expert speech-language intervention.
Surgery is reserved for patients with lesions that show no reversibility with exhaustive medical and speech therapy. Although nodules and polyps may respond to conservative management, vocal cysts typically do not. Delay in surgical treatment and continued trauma can potentially lead to progression of cyst formation and intracordal scarring. The goal of surgical excision is preservation of the mucosal cover with minimal disruption of the underlying tissue. In addition, the deep layers of the lamina propria harbor fibroblasts that produce extracellular proteins. Avoid this layer to prevent scarring along the vocal ligament and tethering of the mucosal cover. The microflap approach to the excision of benign laryngeal lesions was developed with these goals in mind.
A study by Jensen and Rasmussen indicated that microscopic phonosurgery is an effective treatment for benign vocal fold lesions, including cysts. The study included 97 patients who underwent the surgery for vocal fold polyps, cysts, nodules, or edema, with data from postoperative clinical evaluation available for 89 of these individuals. In 85% of the patients, postoperative voice quality was reported to be unaffected, while in 13% of patients, voice quality was improved but moderately affected, and in one patient, with a cyst and sulcus vocalis, voice quality was severely affected.[3]
Diagnostic direct microlaryngoscopy should be considered when the diagnosis of vocal fold cyst is uncertain or when a neoplastic process cannot be excluded.
A retrospective study by Tibbetts et al found that in patients who underwent microflap excision of vocal fold cysts—including 19 with mucus retention cysts and two with epidermal inclusion cysts—improvement in Voice Handicap Index–10 scores did not differ significantly between individuals who were treated with postoperative voice therapy and patients who were not.[4]
Evaluate patients presenting with dysphonia through indirect laryngoscopy and videostroboscopy, with particular attention paid to vocal fold mobility, glottic closure, and the presence, amplitude, and symmetry of the vocal fold mucosal wave. Benign vocal lesions are first treated by reversing the conditions and patterns of abuse that initially created them. Surgery is reserved for patients with unresolving lesions that cause troublesome dysphonia. All known sources of mechanical trauma are maximally reduced prior to considering surgical therapy to determine reversibility and, hopefully, to prevent postoperative recurrence. Medical and speech therapy directed at reducing vocal trauma through improved technique and vocal hygiene are involved in reducing mechanical trauma. Surgical candidates must be willing to postpone speaking and singing engagements for at least 3 months postoperatively.
The lateral microflap is used when the lesion is adherent to the vocal ligament and the overlying mucosa is normal. The advantage of the lateral microflap is that the incision and the subsequent scar are lateral to the medial surface of the vocal fold. In addition, the uninvolved portion of the vocal ligament may be used to orient the flap, and dissection may proceed from known to unknown. The medial microflap is indicated for lesions that involve a discrete portion of the vocal fold and appear to separate easily from the underlying vocal ligament on palpation. This approach allows for a shorter flap and can be used to treat redundant or adherent mucosa overlying a lesion. At the conclusion of the procedure, a solution of triamcinolone acetate may be injected into the flap. This is thought to further minimize scar formation. With both techniques, most patients experience return of mucosal wave and are satisfied with voice quality.
Place the patient on strict voice rest for 2 weeks after microflap surgery. Patients with more extensive dissections may be placed on a short course of corticosteroids. Administer a 7-day course of antibiotics and a mild narcotic for pain relief to all patients. Treat patients with symptoms or findings of laryngopharyngeal reflux with a proton-pump–inhibiting agent.
Reexamine patients at 2, 4, 8, and 12 weeks postsurgery. At the 2-week postoperative visit, perform videostroboscopy and have the patient resume therapy with the speech pathologist. A gradual return to voice use occurs over the first few weeks, increasing by 5-minute intervals twice daily. Singers may begin to work with the vocal pedagogue (ie, singing teacher) at 1 month, but they are cautioned to decrease vocal work if they feel any discomfort or strain. Most patients can expect 90% of their functional surgical result at approximately 3 months.
Complications are related either to laryngoscopy or to vocal fold mucosal injury. Pressure effects from suspension laryngoscopy may result in tongue numbness, altered taste, and oropharyngeal, mucosal, and dental injuries. Deep-plane dissection or exposure of the vocal ligament can result in scarring and fibrosis of the mucosa with loss of mucosal wave and glottal insufficiency. Injudicious use of the laser can result in a wide zone of thermal damage with mucosal scarring and fibrosis, unintended burn injuries, and endotracheal tube fires. The best way to treat scarring is to prevent it. Use of microflap techniques avoids a raw mucosal surface that heals by secondary intention. Avoidance of the deeper layers of the lamina propria and vocal ligament minimizes the fibroblastic response.
Using the microflap technique described above, Courey et al found that 85% of patients with an absent wave preoperatively regained their mucosal wave, while 97% percent of patients with an intact preoperative wave retained this important parameter.[5] Blinded comparison of preoperative and postoperative voice samples from this series showed that the postoperative voice was rated as better in 100% (48 of 48) of patients. Although long-term results in these patients remain excellent, continued emphasis should be placed on the prevention of pathology (eg, voice training, good vocal hygiene, maintenance of systemic health).
Some authors have expressed concern that elevating a microflap may lead to disruption of the attachment of the basement membrane to the superficial layer of the lamina propria through interlinked collagen loops. The mini-microflap was described to minimize tissue manipulation and prevent possible basement membrane injury. The plane of the microflap is in the superficial layer of the lamina propria deep to the basement membrane and likely leaves these attachments untouched. This is demonstrated by the observation of blood vessels within the flap, which clearly reside deep to the basement membrane. Other authors have proposed entering the vocal fold through an anterior, submucosal approach through the thyroid cartilage that obviates the need for an incision in the epithelium. Endoscopes placed into the Reinke space in cadavers allowed for surgery of lesions of the lamina propria.[6] This approach could potentially minimize vocal scarring associated with mucosal incisions and raising subepithelial flaps.
Determining whether the traditional or newer mini-microflap procedures damage or protect the basement membrane or whether basement membrane injury hampers voice is difficult. Results with the microflap have been excellent, with return of good-to-excellent voice and mucosal wave in most patients. Use of the laser in the surgical treatment of benign nodules, polyps, or cysts to minimize scar formation is minimal.
John Schweinfurth, MD, Professor, Department of Otolaryngology, University of Mississippi Medical Center
Disclosure: Nothing to disclose.
Coauthor(s)
Robert H Ossoff, DMD, MD, Maness Professor of Laryngology and Voice, Department of Otolaryngology, Executive Medical Director, Vanderbilt Voice Center, Vanderbilt Medical Center
Disclosure: Nothing to disclose.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Robert M Kellman, MD, Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York Upstate Medical University
Disclosure: Nothing to disclose.
Chief Editor
Arlen D Meyers, MD, MBA, Professor of Otolaryngology, Dentistry, and Engineering, University of Colorado School of Medicine
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Cerescan;RxRevu;Cliexa;The Physicians Edge;Sync-n-Scale;mCharts<br/>Received income in an amount equal to or greater than $250 from: The Physicians Edge, Cliexa<br/> Received stock from RxRevu; Received ownership interest from Cerescan for consulting; .
Additional Contributors
Clark A Rosen, MD, Director, University of Pittsburgh Voice Center; Professor, Department of Otolaryngology and Communication Science and Disorders, University of Pittsburgh School of Medicine
Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Merz North America Inc<br/>Received consulting fee from Merz North America Inc for consulting; Received consulting fee from Merz North America Inc for speaking and teaching.
Indirect laryngoscopy of an intracordal cyst is shown. Note the appearance is similar to that of a nodule or polyp.
This patient had an essentially normal speaking voice but complained of fatigue and loss of vocal range. Note the translucent quality of the mucosal cover.
Indirect laryngoscopy of an intracordal cyst is shown. Note the appearance is similar to that of a nodule or polyp.
Note the translucent outline of the body of the cyst within the mucosal cover of the right true vocal fold. The articulatory surface of the cord is minimally disrupted.
Indirect laryngoscopy of an intracordal cyst is shown. Note the appearance is similar to that of a nodule or polyp.
Note the translucent outline of the body of the cyst within the mucosal cover of the right true vocal fold. The articulatory surface of the cord is minimally disrupted.
This patient had an essentially normal speaking voice but complained of fatigue and loss of vocal range. Note the translucent quality of the mucosal cover.
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