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Year : 2010  |  Volume : 47  |  Issue : 3  |  Page : 239--247

Surgical voice restoration after total laryngectomy: An overview

B Elmiyeh1, RC Dwivedi1, N Jallali2, EJ Chisholm1, R Kazi1, PM Clarke1, PH Rhys-Evans1,  
1 Department of Head and Neck Surgery, Royal Marsden Hospital, Fulham Road, London, SW3 6JJ, United Kingdom
2 Department of Plastic Surgery, Head and Neck Unit, Royal Marsden Hospital, Fulham Road, London, SW3 6JJ, United Kingdom

Correspondence Address:
R C Dwivedi
Department of Head and Neck Surgery, Royal Marsden Hospital, Fulham Road, London, SW3 6JJ
United Kingdom

Abstract

Total laryngectomy is potentially a debilitative surgery resulting in compromise of some of the most basic functions of life including speech and swallowing. This may have a profound adverse effect on the patient«SQ»s physical, functional, and emotional health, and may result in a decreased quality of life (QOL). Until the 1980s, total laryngectomy was regarded as a dreadful, but often, life-saving procedure for which there was little alternative, and was used as a last resort. At that time survival at any cost in terms of QOL was paramount and many laryngectomies were forced into an isolated life as a mute and dysphasic recluse. Most attempts at voice restoration produced inconsistent results and often techniques were laborious, expensive, and ineffective, particularly when carried out as a salvage procedure after failed radiotherapy. Progress in voice rehabilitation, following total laryngectomy, over the last 30 years, has made an enormous difference in the whole concept of the management of laryngeal cancers. Currently there are several options available for these patients, namely, esophageal speech, artificial larynx, and tracheoesophageal speech. The choice of speech rehabilitation varies from patient to patient, but tracheoesophageal voice has become the preferred method. This article provides a brief account of surgical voice restoration after total laryngectomy. Special emphasis has been given to the surgical technique, special considerations, complications, and the prevention / treatment of tracheoesophageal voice restoration.



How to cite this article:
Elmiyeh B, Dwivedi R C, Jallali N, Chisholm E J, Kazi R, Clarke P M, Rhys-Evans P H. Surgical voice restoration after total laryngectomy: An overview.Indian J Cancer 2010;47:239-247


How to cite this URL:
Elmiyeh B, Dwivedi R C, Jallali N, Chisholm E J, Kazi R, Clarke P M, Rhys-Evans P H. Surgical voice restoration after total laryngectomy: An overview. Indian J Cancer [serial online] 2010 [cited 2019 Dec 12 ];47:239-247
Available from: http://www.indianjcancer.com/text.asp?2010/47/3/239/64707


Full Text

 Introduction



Laryngeal cancer has a major impact on the functions of speech and swallowing. This is partly due not only to the destructive process of the disease itself, but also due to the effects of treatment, be it surgery, radiotherapy, and / or chemotherapy. Over the last three decades, the emphasis on restoration of function and quality of life (QOL) has become a key focus of treatment for patients with laryngeal cancer as with other head and neck cancers.

For early stage cancer of the larynx, single modality treatment, be it radiotherapy or conservation laryngeal surgery, results in an excellent outcome, both in terms of survival and function. However, for patients with advanced laryngeal carcinoma, selection of the optimal treatment has become less clear. Some recent studies have shown that chemoradiation regimens provide high rates of laryngeal preservation for T3 and early T4 laryngeal cancers, without affecting survival. [1],[2],[3],[4] Total laryngectomy remains the mainstay of treatment for infiltrative late T4 cancers. The loss of voice, altered swallowing, and a permanent tracheotomy, continue to affect the patients' QOL, both in terms of physical and psychological status. [1]

Although there are numerous options available for these patients; successful voice restoration after total laryngectomy depends on a number of variables. Access to a multidisciplinary head and neck service is one basic necessities. [5] The addition of tracheoesophageal (TE) voice restoration to total laryngectomy has transformed the situation, by providing a good functional outcome and a better QOL for these patients. [5],[6],[7],[8],[9],[10] This is the most widely used technique in surgical voice restoration after total laryngectomy, and is considered to be the gold-standard. [11] Although the tracheoesophageal puncture procedure has been available for over three decades in developed countries; its availability and accessibility in the developing countries is restricted to very few centers, depriving a large patient population. In this article we have focused on the clinically important aspects of tracheoesophageal voice restoration, with the aim of reaching out to a more universal patient population. In many of these countries where a large proportion of the population are unable to write, the additional loss of speech has an even more devastating impact on their QOL.

 History



Ever since the first successful laryngectomy for laryngeal cancer was carried out by Billroth in 1873, [1] there have been many attempts to provide voice to these laryngectomies. In 1874, Carl Gussenbauer an associate of Billroth, designed an artificial larynx, which shunted air from the trachea, past a reed, and into the pharynx. [12] In 1922, Seeman first recognized that the pharynx could act as a neoglottis and the stomach and esophagus as air reservoirs. This was the beginning of the technique of esophageal speech. Guttmann in 1932 described the first tracheoesophageal puncture, when a patient in a suicidal attempt passed an ice pick through his neck (trachea into the esophagus) creating a permanent fistula and, as a result could speak. [13] In 1942, Wright developed the first electronic larynx known as Sonovox. Sound was introduced to the throat by transmission through the soft tissue of the neck. In 1957, Dr. Herbert Cooper and colleagues manufactured an oral-type of electrolarynx. In 1979, Singer and Blom introduced the tracheoesophageal puncture and silicone prosthesis. Since their introduction, variations on the procedure and of the prosthesis have been proposed, but the general principles remain the same today, and are considered as the Gold standard. [14]

 Voice Rehabilitation Options Available to these Patients



Esophageal speech

This method was the mainstay in speech rehabilitation following total laryngectomy, prior to the introduction of surgical voice restoration, in the 1980s. Many people still use this method. Achieving esophageal speech requires the ability to swallow air into the upper esophagus. This is a challenging task, often involving prolonged speech therapy. Coordinated release of this air into the mouth produces vibrations in the mucosal wall of the pharynx and pharyngoesophageal (PE) segment and generates sound. Resonation of the sound occurs in the pharynx, mouth, and nose, with simultaneous articulation using tongue, lips, and teeth. The resulting voice is rough and breathy [15] with a low pitch [16] and reduced loudness. [17] Patients are only able to speak short phrases, [18] as compared to lung-powered speech and may not be satisfied with their voice. [19]

Artifical larynx

This is an alternate method for speech rehabilitation. It produces an artificial laryngeal voice with a mechanical sound quality, which many patients dislike. [15],[20] However, it is particularly useful for those unable to learn or use esophageal speech or TE speech. It works by applying handheld electronic or pneumatic vibrating devices to the side of the throat / cheek or less commonly intra-orally. The sound vibration is transmitted through the head of the device and through the tissues in the neck to the oral cavity, which is then articulated normally allowing a rapid voice acquisition. Early introduction of these devices often alleviates the emotional aggravation due to the inability to speak during the immediate postoperative period, without hindering the efforts in the acquisition of either esophageal or TE speech.

Tracheoesophageal valve speech

It is the newest laryngeal communication option, which approximates near normal laryngeal voice in laryngectomies. [21] In 1979, Singer and Blom introduced the TE puncture [[Figure 1]a and 1b] and silicone prosthesis, [21] which allows air to flow from the trachea into the esophagus. At the same time a 'duckbill' valve prevents aspiration of food and liquid into the trachea. The vibratory segment of the pharynx [Figure 1]a is the source of sound production for both the esophageal and TE speaker. The PE vibratory segment may vary greatly in its position, length, and muscular component. The vibrating PE segment, the resonating vocal tract, and the articulators are the same in both TE and esophageal speech. However, the air reservoir available for TE speech is significantly greater than that for esophageal speech. This allows TE speech to be much louder and more sustained than the esophageal voice, and hence, more similar to laryngeal speech. The quality of the PE segment's mucosa and surrounding muscles is important in voice production, whether esophageal or TE speech. Important features of laryngeal, esophageal, and TE speech are summarized in [Table 1]a.

 Timing, Evaluation, and Patient Selection for TE Speech Restoration



Despite the simplicity of the method of TE puncture, it is crucial to provide a thorough assessment to determine the appropriate candidacy and its timing. This has become even more essential as the medical complexity of patients who require total laryngectomy is escalating. TE puncture can be undertaken at the time of total laryngectomy (Primary) or at a later stage (Secondary). Primary TE puncture offers the optimal timing for voice restoration in a majority of patients in the multidisciplinary setting. [11] It avoids a second operative procedure and allows a quicker and more successful voice restoration. [22] However, there may be unusual situations where delaying this procedure (secondary TE puncture) for a few months may avoid postoperative complications and attain optimal outcome. Secondary TE puncture is considered for patients at risk of developing a fistula such as those who have severe radiation sequelae. [23] Extensive pharyngeal or esophageal resection involving the retrotracheal space is a contraindication to primary TE puncture, as the risk of fistula formation is very high. Unrealistic patient expectations, poor patient motivation, manual dexterity, visual acuity, and respiratory function may compromise their ability to utilize TE speech, and hence, are relative contraindications to TE puncture. There is apparently no significant difference in patient satisfaction on the subjective and objective assessments of voice quality in patients undergoing primary or secondary TE puncture.[24] The advantages and disadvantages of primary and secondary TE punctures are mentioned in [Table 1]b.

In established laryngectomies careful investigation and selection is even more critical for secondary voice restoration, in order to achieve success. Preoperative evaluation of patients considered for secondary TE puncture can be achieved by videofluoroscopy (VF). This is the most accurate method for assessing PE segment tonicity and function after laryngectomy. [25],[26],[27] Videofluoroscopy is a dynamic test with three important components; a modified barium swallow, attempted phonation, and an esophageal insufflation test. The preoperative insufflation test is an excellent preoperative indicator of postoperative TE speech production. Patients also benefit from hearing the potential quality of their TE voice after puncture. This is particularly true for patients whose pharynx has been reconstructed following pharyngolaryngectomy or pharyngolaryngoesophagectomy. The insufflation test involves insertion of a catheter through the nose until the end is just below the PE segment. Air is channeled through the catheter to insufflate the esophagus, simulating TE speech. Attachment of a manometer to the insufflation catheter allows measurement of pressure and constrictor tonicity within the PE segment.

Tonicity, surgeon and patient choice, local services, and party-wall thickness determine the choice of speaking valve to be used. In summary, a patient who is otherwise in good health, strongly motivated, and determined to achieve voice after laryngectomy will usually succeed, provided the surgeon and speech pathologist have the knowledge and expertise to manage any problems and complications that arise.

 Surgical Technique and Special Considerations



Laryngectomy is carried out in the usual fashion, preserving as much pharyngeal mucosa as possible, particularly over the postcricoid region and the piriform fossae, provided safe clearance from the tumor is obtained [[Figure 2]a and 2b]. This is to ensure adequate voice restoration and swallowing as well as minimizing the need for flap reconstruction. Augmentation of the pharynx with a flap is warranted when the residual mucosal strip is small ( [28] Some surgeons prefer to place a nasogastric (NG) tube instead of a catheter; the final choice depends on the surgeon's individual preference.

The pharyngeal mucosal defect is then closed meticulously with a Connell inverting stitch, in a horizontal fashion [Figure 5]a. This produces a wider pharynx above the PE segment. Vertical closure creates a long narrow pharyngeal segment, which can potentially affect the swallowing and speech functions. The "T" closure is widely used, but there may be an increased risk of a fistula formation at the three point intersection. Significant resection of the hypopharynx will necessitate a flap reconstruction.

The PE segment is reconstructed by affixing the thyropharyngeus constrictor muscle remnants together and joining the suprahyoid muscles to it [Figure 5]b. This is to create a tonic PE segment and a resonating pharyngeal segment above it. The upper flap is sutured to the margin of the trachealis muscle on the posterior wall of the trachea. This reconstruction ensures that the tracheal rings are pulled laterally, to maintain an adequately sized stoma (20 - 25 mm), large enough to allow adequate respiration and small enough for easy occlusion. Attention should be given to the junction of the tracheocutaneous mucosa, as the shape and configuration of the stomal edge will be important for achieving successful hands-free TE speech. Ideally the parastomal neck contour should be flat to help ensure optimal adhesion of the tracheostoma valve housing. [29] This can be achieved by detaching some of the inferomedial sternocleidomastoid tendon fibers. Absorbable sutures can be placed between the esophageal wall and the posterior aspect of the trachealis, on either side of the proposed position of the puncture, if there is a separation of the party-wall.

The neck wound is closed routinely with suction drainage. The patient is fed through the catheter / NG tube and oral intake is commenced usually after about seven days. However, in pre-irradiated cases, oral feeding is started on the tenth day following a water soluble contrast swallow test. to exclude any leaks from the pharynx. Once adequate oral feeding has been started the catheter / NG tube is removed and replaced with a suitable TE prosthesis.

The technique of TE puncture with prosthetic voice restoration was originally developed by Singer and Blom, as a secondary procedure for those patients who had failed to achieve adequate esophageal speech. [21] The voice produced was reliable and had good quality, lung-powered speech, but there were significant problems associated with the use of a rigid endoscope used to access down to the stoma level. [30],[31],[32],[33] Similar problems with access, using the rigid endoscope, prompted the development of an alternative method [34] of using a modified pair of curved Lloyd-Davies forceps, which have been used successfully in a series of 94 secondary voice punctures since 1984, with no failed or abandoned procedures. [28] The forceps are inserted alongside a pharyngeal speculum into the esophageal opening under direct vision and advanced down to the level of the tracheotomy, where the tip tents up the posterior tracheal wall [Figure 6]a and b. The rest of the surgical procedure is similar to that of primary voice restoration.

 TE Voice Prostheses



There are a variety of TE voice prostheses, which vary according to length, diameter, material, retention flange, and resistance to airflow. Transesophageal voice prostheses are generally classified into one of two categories. Standard devices can be changed by the patient without medical supervision. These types of voice prostheses are generally less expensive and need to be replaced more frequently than do the long-term devices, often referred to as indwelling-type prostheses. Indwelling-type prostheses have robust retention collars and require placement by a qualified speech pathologist or clinician.

 Complications, Problems, and Solutions



The tracheoesophageal voice success rate following total laryngectomy varies between 70 - 95%. [35],[36],[37] Voice failure after prolonged speech therapy may be due either to TE puncture or prosthesis related complications / problems or may be due to poor understanding or motivation of the patient. The most common problem encountered by these patients is leakage through and / or around the valve.

The atraumatic technique of insertion, proper cleaning of the puncture, and selection of adequately fitting prosthesis are essential. Different prostheses have different life-spans and the normal wear and tear of the valve will eventually cause leakage through the valve. Biofilm formation through colonization of the prosthesis with Candida species and commensal oral microflora can also cause leakage through the prosthesis. Antifungal treatment can prolong the lifespan of the prostheses. [38] The long-term use of an antimicrobial can potentially induce the development of resistant strains. It has been suggested that development of alternative therapeutic agents such as biosurfactants and probiotics may prevent microbial biofilm formation and may resolve this problem. [39] The 'Advantage' Blom-Singer; indwelling voice prosthesis contains silver oxide, which acts as an antimicrobial agent, reducing the need for antifungal medication. [40] The pathological gastroesophageal reflux disease (GERD) has been reported in as high as 82% of the total laryngectomy patients [41] and can potentially cause TE valve failure. Aggressive anti-reflux therapy can ameliorate this problem. [42] Fundoplication can eliminate symptoms of gastroesophageal reflux and can resolve regurgitation-associated prosthesis erosion in extreme cases. [43]

Enlarged TE fistula can cause leakage around the prosthesis. This may be related to the use of a wide diameter valve in a thin party-wall or tumor recurrence. Collagen [44] or autologous fat injection [45],[46] can improve the seal around the prosthesis and prevent leakage. Too long a prosthesis can move like a piston in the TE fistula causing leakage around the valve. This can be corrected by downsizing the valve. It is paramount to remain vigilant, as tumor recurrence can also cause leakage around a valve.

Sometimes a thick ring of fibrous tissue is developed around the prosthesis. [28] This effectively lengthens the tract and draws the posterior end of the valve forward into the tract. If the ring is not too prominent the tract can be resized and a longer valve fitted. Otherwise it can easily be excised.

Occasionally granulation tissue forms around the prosthesis at the TE puncture site as a result of trauma or irritation to the mucosa. This is more likely if the prosthesis is in situ for too long and / or fits too tightly within the TE tract. [28] Granulation tissue can be easily cauterized or excised.

Extrusion of prosthesis may occur from the TE tract during cleaning or coughing. If the valve is not replaced immediately, stenosis of the tract will occur eventually resulting in complete closure of the posterior TE puncture site. [28] A catheter or dilator may be used to stent the tract until the prosthesis can be replaced.

The primary cause of TE voice failure continues to be pharyngeal constrictor hypertonicity or spasm. [28] This can usually occur if cricopharyngeal myotomy is performed inadequately. The use of Clostridium botulinum toxin, a neurotoxin, to relieve constrictor hypertonicity or spasm has become the preferred method of treatment, as it is an effective, simple, and office-based procedure. [47] Myotomy is now rarely required and is reserved for circumstances in which the botulinum injection has been ineffective in relieving a spasm.

Pseudoepiglottis is most often related to the surgical closure of the pharynx during laryngectomy. The anterior pouch at the tongue base and the coronal fibrous web / bar behind it may cause dysphagia, characterized by stasis of swallowed material within the anterior pouch that may not be cleared despite repeated swallowing. Patients may also complain of regurgitating small amounts of undigested food along with a wet, gurgly TE voice. [28] The condition can be diagnosed by videofluoroscopy and the treatment remains dividing the band using a stapling gun or Laser.

Stenosis, narrowing of the pharyngoesophagus, may occur if insufficient mucosa / skin has been used for reconstruction of the hypopharyngeal defect or at the anastomotic site. [28] It is also possible in heavily irradiated patients or in those where the surgical closure has been tight. Dilatation may be sufficient if the narrowing is not severe, but in some cases surgical resection is required.

Constrictor hypotonicity is generally associated with a flaccid PE segment and results in a weak, breathy TE voice. It occurs as a result of the loss or absence of muscular tone or when the PE lumen is large. [28] Voice quality may be improved by applying external pressure over the pharynx or the anterior neck. The outcome of surgical attempts to correct this problem have been variable. Excessive collection of air in the stomach is a disturbing and sometimes painful problem in TE voice users. This may be due to the negative esophageal pressure during inspiration and a hypotonic or hypertonic PE segment. Replacement of the prosthesis with a higher resistance duckbill valve may provide a solution.

The size of the tracheostoma is important for TE speakers who will digitally occlude in order to produce voice. [28] The insertion and retention of the prosthesis depends on the size, shape or position of the stoma. Stomal ulcerations often result from ill-fitting prostheses, causing recurrent local trauma. Use of adequate size prosthesis can prevent stomal ulceration.

 Conclusion



New surgical techniques and voice prostheses have increased the population of patients suitable for TE voice restoration. This has a positive impact on the QOL for patients undergoing total laryngectomy. The success rate is higher in a multidisciplinary setting. This is due to careful patient selection, prudent preoperative planning, meticulous surgical technique, and the correct selection and insertion of prostheses. Patient education and motivation, prosthesis care, early identification, and evaluation of voice failure are crucial in achieving optimal voice outcome. The importance of adequate voice rehabilitation is even greater in third-world countries, where indiscriminate promotion of tobacco usage and smoking, poor hygiene, and adverse environmental conditions have made laryngeal and other head and neck cancers much more common. Survival rates, if available, are poor due to late presentation, lack of expert surgical and radiotherapy treatment, and a wide range of inadequate healthcare facilities. Indeed, many patients are not even offered the chance of curative treatment. Of those who undergo and survive laryngectomy, many are illiterate and the isolation is far more profound if they cannot communicate even by writing. Successful TE voice restoration in these patients is very rewarding, but the cost and other problems associated with maintaining the prosthesis are often prohibitive.

 Acknowledgment



The authors would like to acknowledge Dr. Eric D Bloom and Dr. Jan S Lewin for their valuable contribution. Author Elmiyeh B and Dwivedi RC contributed equally to this work.

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