75 Benign Vocal Fold Lesions & Microsurgery

Question 1

What’s the definition of phonomicrosurgery?

Answer 1

What’s the definition of phonomicrosurgery?

One of the founding fathers of modern day laryngology, Hans von Leden, originally introduced the term “phonosurgery” in 1963 to describe procedures that alter vocal quality and pitch. As technology and the understanding of the delicate vocal fold anatomy advanced, the term “phonomicrosurgery” became popularized. It is usually performed using very fine micro instruments aided by a high-powered microscope to remove the vocal fold lesion and maximize preservation of normal anatomy.

Question 2

What are the indications for phonomicrosurgery?

Answer 2

What are the indications for phonomicrosurgery?

The most common indication for phonomicrosurgery is for the removal of benign lesions to restore the normal prephonatory glottic configuration of the larynx. It may also be used to resect precancers and early cancers of the glottis.

Question 3

How is phonomicrosurgery different from the traditional vocal fold stripping with regard to the management of vocal fold lesions?

Answer 3

How is phonomicrosurgery different from the traditional vocal fold stripping with regard to the management of vocal fold lesions?

Vocal fold stripping is usually performed by grabbing the lesion with a cup forceps and “tearing” it off the vocal fold. There is no fine control of the depth of injury with vocal fold stripping. Furthermore, the lack of precision may result in excessive removal of normal tissue.

Question 4

What are the layers of the membranous vocal fold?

Answer 4

What are the layers of the membranous vocal fold?

Stratified squamous epithelium, basement membrane, the superficial lamina propria (SLP), the vocal ligament (the intermediate and deep lamina propria), and the vocalis muscle.

Question 5

What is the histology of the lamina propria?

Answer 5

What is the histology of the lamina propria?

Fibroblasts make up the main cellular component of the lamina propria, while glycosaminoglycans and proteoglycans occupy the interstitial spaces within the extracellular matrix.

Question 6

Why is the SLP often referred to as Reinke’s space?

Answer 6

Why is the SLP often referred to as Reinke’s space?

The superficial lamina propria has often been described incorrectly as a potential space. It is about 0.5 mm in thickness and is a distinct anatomic structure. Thus the eponym of Reinke’s space is a misnomer.

Question 7

What are the components of the SLP?

Answer 7

What are the components of the SLP?

The SLP is composed mostly of extracellular matrix proteins, water, and loosely arranged fibers of collagen and elastin. The SLP is mostly gelatinous in nature.

Question 8

What are the components of the vocal ligament?

Answer 8

What are the components of the vocal ligament?

It is composed mostly of elastin and collagen. As the vocal ligament transitions from the intermediate to the deep layer of lamina propria, there is a denser arrangement of collagen.

Question 9

What is the body-cover model of vocal fold motion?

Answer 9

What is the body-cover model of vocal fold motion?

The cover of the vocal fold includes the epithelium and the SLP. The vocal ligament and the vocalis muscle make up the body. Some authors consider the vocal ligament as a transition zone. As air passes between the vocal folds from the lung, the loose mucosa (epithelium and SLP) moves like a wave over the denser vocal ligament and vocalis muscle.

Question 10

How do laryngeal lesions cause dysphonia?

Answer 10

How do laryngeal lesions cause dysphonia?

By altering the cover viscosity, interfering with the body-cover relationship, and distorting prephonatory glottic configuration.

Question 11

What are the principals of phonomicrosurgery?

Answer 11

What are the principals of phonomicrosurgery?

The principals are based on the body-cover model of the vocal fold vibration. Given the importance of the interaction between the cover and the body, phonomicrosurgery for most benign lesions has evolved to limit the dissection to the depth and extent of the lesion and to maximize the preservation of normal microarchitecture. For removal of malignancy, the same principal applies; however, the primary goal is to achieve a negative margin, thus normal tissue may be sacrificed to ensure cancer extirpation.

Question 12

What is the plane of dissection for most phonomicrosurgery?

Answer 12

What is the plane of dissection for most phonomicrosurgery?

Dissection is within the SLP. Usually after incising the epithelium of the vocal fold, the SLP can be easily entered using a flap elevator. The vocal ligament is dense and appears to be pearly white (Figure- Elevating a leukoplakic lesion off the epithelium of the vocal fold using microflap technique).

Question 13

Can you use a laser to achieve the similar control and precision as cold steel instruments?

Answer 13

Can you use a laser to achieve the similar control and precision as cold steel instruments?

Yes. Modern laser technology such as the carbon dioxide (CO2) laser with an articulating arm can be attached to an operative microscope. With specific software and hardware modifications, one can achieve precise control of the depth and thickness (Figure- Microphonosurgery with a CO2 laser. Left figure demonstrates shaving of respiratory papilloma off the free edge of the vocal fold. Right figure demonstrates ablating papilloma off the superior surface of the vocal fold.).

Question 14

Why is laryngostroboscopy a vital part of the preoperative evaluation for phonomicrosurgery?

Answer 14

Why is laryngostroboscopy a vital part of the preoperative evaluation for phonomicrosurgery?

Stroboscopy can assess vibratory property and glottic closure pattern of the vocal folds. These findings allow the clinician to predict the type and depth of the lesion. In other words, stroboscopy is the only clinically available tool that allows clinicians to assess the “suppleness” of the vocal folds. High-speed photography is another method to evaluate the vibratory property; however, this is rarely feasible due to the cost and size of the equipment. A detailed discussion of the specific findings on laryngostroboscopy is beyond the scope of this chapter; interested readers are referred to the publication by Kitzing in the reference section.

Question 15

What are the common benign laryngeal lesions treated with phonomicrosurgery?

Answer 15

What are the common benign laryngeal lesions treated with phonomicrosurgery?

Vocal fold polyps and cysts, polypoid corditis (Reinke’s edema), and recurrent respiratory papilloma.

Question 16

What are vocal fold nodules?

Answer 16

What are vocal fold nodules?

These are bilateral and symmetric midmembraneous vocal fold lesions that are usually due to inefficient voice use. On laryngostroboscopy, there is minimal alteration in the normal vibratory property of the vocal folds. They tend to resolve with behavioral modification and voice therapy. Vocal fold nodules are rarely managed surgically.

Question 17

What are vocal fold polyps?

Answer 17

What are vocal fold polyps?

These lesions are classically exophytic and can be clear or vascularized in appearance. Chronic vocal strain may lead to the formation of clear appearing, gelatinous polyps. Some phonotraumatic polyps may develop aberrant vessels and present as vascularized polyps. The vascularized polyps may hemorrhage into the vocal fold if there is an acute episode of violent cough or phonotrauma. Polyps can present unilaterally or bilaterally and usually do not lead to significant perturbation of the normal vibratory properties when they are small; however, most polyps do not respond completely to voice therapy.

Question 18

What are vocal fold cysts?

Answer 18

What are vocal fold cysts?

These lesions can be unilateral or bilateral. There is the subepithelial type which is thought to be the product of an obstructed mucous gland and may cause mild change in the vibratory properties. A deeper intraligamentous (in the vocal ligament) type may cause significant impairment to vocal fold vibration. Vocal fold cysts usually do not respond to voice therapy and eventually require surgery.

Question 19

What underlying etiologies are shared by some benign lesions such as vocal fold nodules, polyps, and cysts?

Answer 19

What underlying etiologies are shared by some benign lesions such as vocal fold nodules, polyps, and cysts?

The development of these vocal fold lesions is often related to the patient’s inefficient phonatory pattern that leads to excessive vocal fold collision and trauma. Sometimes the traumatic phonatory pattern may be a compensatory behavior due to glottic insufficiency.

Question 20

What is Reinke’s edema (also known as polypoid corditis)?

Answer 20

What is Reinke’s edema (also known as polypoid corditis)?

Reinke’s edema presents as diffuse swelling of one or both vocal folds. As the result of significant increase in vocal fold mass, the patient speaks with a lower-pitched and harsher voice. The degree of reduction in mucosal wave correlates with the size of the lesion. In extreme cases, bilateral Reinke’s edema can cause obstruction of the glottic airway. This lesion is usually associated with tobacco abuse. Often patients are asked to quit smoking before surgical excision is attempted.

Question 21

What are vocal fold scars or sulcus vocalis?

Answer 21

What are vocal fold scars or sulcus vocalis?

When there is irreversible loss of viscoelasticity to the superficial lamina propria, a scar or sulcus vocalis forms. These patients normally have a history of voice abuse. If the tissue loss is significant, the patient may also experience glottic insufficiency. Phonomicrosurgery rarely improves the mucosal wave vibration. Augmenting the vocal fold with an injectable or permanent implant may correct the glottic insufficiency and thus provide more vocal projection and volume.

Question 22

What kinds of precancerous and cancerous lesions can be treated with phonomicrosurgery?

Answer 22

What kinds of precancerous and cancerous lesions can be treated with phonomicrosurgery?

Dysplasia, squamous cell carcinoma in situ, and early vocal fold squamous cell carcinoma.

Question 23

What are the different techniques for endoscopic excision of early glottic cancer?

Answer 23

What are the different techniques for endoscopic excision of early glottic cancer?

Squamous cell carcinoma in situ and superficial early stage squamous cell carcinomas can be removed with a microflap technique staying superficial to the vocal ligament. If the lesion extends into or through the vocal ligament, endoscopic carbon dioxide laser–assisted cordectomy is an excellent treatment modality that rivals radiation therapy in cure rate.

Question 24

What’s the most important predictor of voice outcome following endoscopic vocal fold cordectomy for cancer resection?

Answer 24

What’s the most important predictor of voice outcome following endoscopic vocal fold cordectomy for cancer resection?

The deeper the excision the more unpredictable the voice outcome becomes.

Question 25

What common pathologies can lead to glottic insufficiency?

Answer 25

What common pathologies can lead to glottic insufficiency?

Vocal fold paralysis or paresis and vocal fold atrophy as related to aging or neurologic disease.

Question 26

Why is preoperative voice therapy important in the management of many benign laryngeal lesions?

Answer 26

Why is preoperative voice therapy important in the management of many benign laryngeal lesions?

Voice therapy can ameliorate abusive phonatory patterns, so the patient is less likely to cause further trauma to the vocal folds postoperatively. Furthermore, some patients may be satisfied with their voice after therapy so that they no longer need surgery. Last, for benign laryngeal lesions, phonomicrosurgery is an elective procedure, and one or two sessions of voice therapy can solidify the patient-physician relationship.

Question 27

What are the potential complications of phonomicrosurgery discussed with the patient preoperatively?

Answer 27

What are the potential complications of phonomicrosurgery discussed with the patient preoperatively?

Since the larynx is part of the airway, there is always a risk for airway obstruction during and after the procedure. Making an incision in the vocal fold may cause scar formation and thus worsen the patient’s voice. A rigid laryngoscope provides the surgeon with the exposure of the vocal folds, and the laryngoscope rests on the teeth and tongue; thus dental injury, lip laceration/abrasion, and taste changes can all occur. Lesions that are due to voice abuse may recur if the patient maintains the same vocal behavior.

Question 28

What equipment is usually needed to perform phonomicrosurgery?

Answer 28

What equipment is usually needed to perform phonomicrosurgery?

A specialized laryngoscope is used to expose the larynx. As a general rule, the surgeon should use the largest laryngoscope that the patient can safely tolerate. A suspension system is used to place the laryngoscope in a fixed position. A high-powered operative microscope is used to provide a magnified binocular view of the vocal folds. A 0-degree and/or 70-degree telescope can be used to take operative photos and closely examine the lesion. The main microlaryngeal instruments are small suctions to remove blood and mucus, sickle knife to make incisions, flap elevators to dissect the lesion, forceps to grab and retract the lesion, and scissors to extend the incision. Different lasers can also be used.

Question 29

What is the typical duration of voice rest after phonomicrosurgery?

Answer 29

What is the typical duration of voice rest after phonomicrosurgery?

Patients may be placed on complete voice rest for 0 to 14 days and gradually increase their vocal use while working closely with the surgeon and the speech-language pathologist. Some patients may not go back to unrestricted voice use until 30 to 60 days postoperatively, especially professional singers and patients with large lesions. The appropriate amount of prescribed voice rest or conservation is under constant debate. Ultimately, the postoperative care should be individually tailored based on the type and size of the lesion, the degree of tissue deficiency, the patient’s current voice use pattern and projected vocal requirement, and the clinical experience.