|Year : 2015 | Volume
| Issue : 4 | Page : 800-806
Voice rehabilitation after total laryngectomy
Mohammed K El-Sharnobya1, Essam A. W. Behairya1, Ayman A Abdel-Fattah1, Mahmoud A Al-Belkasy MBBCh 2
1 Department of Otorhinolaryngology, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Beiala Hospital, Kafer El-Sheikh, Egypt
|Date of Submission||30-Sep-2014|
|Date of Acceptance||29-Dec-2014|
|Date of Web Publication||12-Jan-2016|
Mahmoud A Al-Belkasy
Abd-Allah Bn Massoud Street, Beiala City, Kafer El-Sheikh Governate, 32511
Source of Support: None, Conflict of Interest: None
The aim of the study was to review the different options for voice rehabilitation to improve the quality of life of laryngectomized patients after total laryngectomy.
Data for the study were collected from previous investigations and reviews as well as from medical websites (PubMed, Medscape, MD Consult) and scientific journals.
Studies were selected for evaluating new advancements in voice rehabilitation after total laryngectomy.
In this review data from published studies were manually extracted and summarized.
Total laryngectomy is potentially a debilitative surgery resulting in compromise of some of the most basic functions of life, including speech and swallowing. At present, there are several options available for these patients: 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.
No single method is considered the best for all patients, but tracheoesophageal puncture has become the preferred method in the past decade.
Voice rehabilitation is one of the most important determinants of the quality of life after total laryngectomy. Recent advances in prosthetic voice devices have made them the gold standard for voice rehabilitation. Thus, voice rehabilitation is preferred and used more often than other methods (esophageal speech and artificial larynx). There is ongoing research to find solutions to the most common complications of tracheoesophageal puncture.
Keywords: laryngeal cancer, laryngectomy, pharyngoesophageal segment, tracheoesophageal voice, voice restoration
|How to cite this article:|
El-Sharnobya MK, Behairya EA, Abdel-Fattah AA, Al-Belkasy MA. Voice rehabilitation after total laryngectomy. Menoufia Med J 2015;28:800-6
|How to cite this URL:|
El-Sharnobya MK, Behairya EA, Abdel-Fattah AA, Al-Belkasy MA. Voice rehabilitation after total laryngectomy. Menoufia Med J [serial online] 2015 [cited 2020 Sep 20];28:800-6. Available from: http://www.mmj.eg.net/text.asp?2015/28/4/800/173591
| Introduction|| |
Total laryngectomy results in physical and functional changes that can affect the emotional well-being and some of the most basic functions of life, including breathing, swallowing, and communication  .
Most attempts at voice restoration produced inconsistent results, and techniques were often laborious, expensive, and ineffective, particularly when carried out as a salvage procedure after failed radiotherapy. Progress in voice rehabilitation following total laryngectomy has, over the last 30 years, made an enormous difference in the whole concept of the management of laryngeal cancers. There are several options available for these patients; old options include esophageal speech and artificial larynx and the recent option is tracheoesophageal speech. The choice of speech rehabilitation varies from patient to patient  .
In laryngeal amputation an incision is made in the neck and the entire laryngeal mechanism is removed, from the hyoid bone to the upper two to three rings of the trachea. Structures that are removed include the hyoid bone, epiglottis, thyroid, cricoid, and arytenoid cartilages, the upper two to three rings of the trachea, and surrounding musculature including the strap muscles. The surgeon then redirects the trachea and sutures it to the area of the external neck that lies just above the notch of the sternum. This opening in the neck is called a stoma and it serves as the point of air exchange with the atmosphere as there is no longer a connection between the trachea and the pharynx, nose, and mouth. The surgeon also sews the hypopharynx to the upper esophagus so that the passage of liquids and food remains the same as before the surgery. Removal of the larynx by laryngectomy causes alterations in many important functions, including respiratory, circulatory, fixative, protective, phonatory, olfactory, and coughing. The source of voice is produced by vibration of the two vocal folds within the larynx, which are removed during a total laryngectomy. Because of the loss of vocal mechanism, an alternate form of communication must be learned after laryngectomy  .
| Objective|| |
The aim of the study was to review the different options for voice rehabilitation to improve the quality of life of laryngectomized patients after total laryngectomy.
| Materials and methods|| |
Data were collected from previous investigations and reviews as well as from medical websites (PubMed, Medscape, MD Consult) and scientific journals.
Studies were selected for evaluating advancements in voice rehabilitation after total laryngectomy under different methods.
In this review data from published studies were manually extracted and summarized.
In this review, data from several studies on voice rehabilitation after total laryngectomy were included. There are different methods for voice rehabilitation after total laryngectomy, each having advantages and disadvantages. We obtained our results after studying the different methods of voice rehabilitation after total laryngectomy and analyzing the data to identify the most preferred technique after taking into consideration the complications of each method.
| Results|| |
No single method is considered the best for all patients, but tracheoesophageal puncture (TEP) has become the preferred method in the past decade. Despite the potential for voice production with the TEP, careful attention must be directed to pharyngoesophageal (PE) segment integrity and mucosal density, valve selection, and troubleshooting, voice restoration is a process, not a prosthesis. Speech-language pathologists and otolaryngologists are responsible for providing patients with information about their various communication options and allowing the laryngectomy to make choices based on personal desires and capabilities.
| Discussion|| |
Methods of voice rehabilitation
Speech impairment occurs in 34-70% of head and neck oncologic patients. Management of this impairment is through surgical and nonsurgical methods. Nonsurgical methods of voice rehabilitation include the electrolarynx (EL), pneumatic artificial larynx, and esophageal speech. Surgical methods include tracheoesophageal voice using voice prosthesis, neoglottis, and laryngeal transplantation  .
Esophageal speech entails trapping air in the mouth or the pharynx and swallowing it into the esophagus. The patient can then reflux air up through the esophagus, vibrating the PE segment. This produces a belch-like sound that can be articulated by the vocal tract  .
There are two methods by which air can be pumped into the cervical esophagus: the injection method and the inhalational method.
Injection method: In this method the person builds up enough positive pressure in the oral cavity, forcing air into the cervical esophagus. This is achieved by elevating the tongue against the palate. Air can also be injected into the cervical esophagus by voluntary swallowing. Lip closure along with elevation of the tongue against the palate generates enough positive pressure within the oral cavity to force air into the cervical esophagus. This method is also known as tongue pumping, glossopharyngeal press, and glossopharyngeal closure. This method is effective before producing obstructed sounds like plosives and stricted vocal tract sounds like fricatives and africatives  .
Inhalational method: This method uses the negative pressure used in normal breathing to allow air to enter the cervical esophagus. The air pressure in the cervical esophagus below the cricopharyngeal sphincter has the same negative pressure as air in the thoracic cavity. Hence, during inspiration, this pressure falls below atmospheric pressure. Laryngectomies relax the cricopharyngeal sphincter during inspiration, thereby allowing air to enter the cervical esophagus as it enters the lung. This trapped cervical column of air is responsible for speech generation. Patients are encouraged to consume carbonated drinks during the initial phases of rehabilitation. Gases released can be expelled into the cervical esophagus causing speech generation  .
Advantage: The major advantage of esophageal speech is that it is hands-free speech and requires no extra equipment or repairs. It is a naturally produced sound and the patient is not dependent on devices  .
Disadvantage: Significant speech therapy training is required to become a proficient esophageal speaker. Around 40-74% of patients who have undergone laryngectomies fail to acquire functional esophageal speech. Controlling pitch, loudness, and rate of speech can be difficult for esophageal speakers. The fundamental frequency for esophageal speech is approximately 65 Hz, extended learning period  .
Electronic artificial larynx
An EL is a battery-powered device that incorporates the internal preset pitch that can be adjusted to meet the individual preference for male and female speakers. Rothman found that the use of the EL was easier, produced longer sentences without special care, and was more effective for communication in many situations  .
There are two types of EL: the neck type and the intraoral type.
The neck-type EL ([Figure 1]) is the most widely used in laryngectomy because it is easy to handle and is hygienic  . During phonation, the hand-held device is held against the neck approximately at the level of the former glottis to put the sound into the oral and pharyngeal cavities by an electromechanical vibrator. The vibrated electronic sound source is transmitted through the neck tissues, where the user modulates it to create speech by movements of articulators such as the lips, teeth, tongue, jaw, and velum  .
|Figure 1 Electrolarynx. The device is placed externally on the pharynx, a button is pushed, and the electrolarynx transmits a vibratory noise.|
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The particularity of the intraoral type of EL ([Figure 2]) is the path that the sound is transmitted through. With the use of an intraoral tube, sound is transmitte into the mouth directly. Therefore, the energy leakage of the sound is limited and the speech quality is better as compared with the neck-type EL  .
The UltraVoice is an intraoral remote-controlled device ([Figure 3]) that can be custom-built into the top of an upper denture or orthodontic retainer. The basic unit worn in the mouth comprises three components. The first of these is a loudspeaker covered by a silicone membrane to protect it from saliva, food, and liquid. According to the manufacturer, the speech tone can be adjusted to that of a typical male or female voice, thereby simulating sound produced by a normal larynx. The second component is a miniature electronic circuit that allows the user to adjust the pitch and volume. The final component comprises two small batteries that are the power source for the loudspeaker and a control circuit for an average day of talk time. The remote control is powered by batteries, has a slide button that turns the UltraVoice on or off, and adjusts both pitch and volume  .
|Figure 3 Denture-based intraoral vibrator. The denture is fixed on an upper jaw.|
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Surgical methods of voice rehabilitation
Tracheoesophageal voice using voice prosthesis
The aim of surgical voice restoration procedures is to use the lungs as an airflow source and prevent the aspiration of ingested material. To obtain TE speech for the patient, the surgeon must create a fistula or puncture for the placement of a small tube, voice prosthesis (VP), into the tissue (often termed common wall) that divides the trachea from the esophagus. This TEP is created either at the time of the total laryngectomy (primary puncture) or at a later time (secondary puncture). The VP is a one-way air valve that shunts air from the trachea into the esophagus when the speaker occludes the tracheostoma. The shunted air vibrates the esophageal tissue in the same way as the forced vibration in esophageal speech, resulting in voice. Voice prostheses are not only important in the process of voice production, but they also aid in maintaining the TEP and in preventing food and liquid from passing from the esophagus into the trachea during swallowing. Swallowing is a great risk, as inhalation of foods and liquids can contribute to the development of aspiration pneumonia and reduced lung volume  .
The first prostheses to be developed were designed as ex-dwelling devices to be cared for by the patient. Then hands-free devices were developed, followed by low-pressure devices. Ex-dwelling devices can be removed, cleaned, and reinserted by the patient. In-dwelling prostheses need less dexterity on the part of the patient and can be cleaned in situ. They are periodically replaced by the otolaryngologist or the speech-language pathologist  . [Figure 4] shows the different types of valves.
|Figure 4 Tracheoesophageal puncture and prosthesis. A fistula is created between the posterior wall of the trachea and the anterior wall of the esophagus. The patient occludes the tracheostoma with a finger, and the air is diverted into the esophagus and pharynx to create sound.|
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Brown et al.  found no difference in patients undergoing primary or secondary TEP. The procedure can be performed in postradiotherapy patients who have undergone a neck dissection or have previously undergone a laryngectomy. Patients can start speaking within a few days of surgery, which benefits the patient's psychological state. Closure of the fistula can be easily achieved if the patient desires. Tracheoesophageal speech utilizes the pulmonary air supply to produce sound  . It is closer to laryngeal speech when compared with voice parameters such as fundamental frequency, words per minute, and maximum phonation time. In tracheoesophageal speech, more air is available for speech as the entire tidal volume of expired air, which is 500 ml, is much more in comparison with esophageal speech, which is around 40-70 ml. As the speech is lung powered the speech is louder, more fluent in quality, and more sustained when compared with esophageal speech.
Advantage: The advantages of TEP include the following  :
- It can be performed after laryngectomy, neck dissection, and/or radiotherapy.
- The fistula is a convenient route for esophagogastric feeding in the immediate postoperative period.
- Speech is attained more quickly compared with esophageal speech.
- The success rate of prosthetic vocal rehabilitation is high (close to 95% in long-term users).
- Fair-to-excellent voice quality is achieved in nearly 88% of patients.
- It is similar to laryngeal speech on a range of voice parameters such as fundamental frequency, jitter, shimmer, words per minute, and maximum phonation time as compared with esophageal speech.
- It is more intelligible, natural sounding, and there is improved intensity and duration of speech.
Disadvantage: The disadvantages of TEP include the following  :
- Need to manually cover the stoma when voicing, although in many cases this has been relieved by the creation of hands-free valves.
- Adequate pulmonary reserve is necessary.
- Additional surgery for secondary punctures.
- Violation of the posterior esophageal wall.
- Inadvertent passage of the catheter through a false passage, and esophageal perforation.
Selecting a prosthesis: There are numerous factors that speech-language pathologists and otolaryngologists must consider when establishing TE speech in a patient: length of VP, expense, diameter, type of retention collar, method of insertion, need for follow-up care, risk of VP aspiration, and the patient's ability to care for the prosthesis. The wrong decision may lead to patients who have undergone a laryngectomy not being able to communicate vocally. Choosing a prosthesis that is too short may result in closure, whereas one that is too long will result in leakage and aspiration. The wrong prosthesis may also pose more serious complications including pneumonia (due to chronic aspiration of fluids into the airway through the prosthesis) and airway compromise associated with the prosthesis occupying space in the tracheostoma or actually dislodging and falling into the trachea  .
The person designated the responsibility of removing and replacing improperly functioning devices is also an important factor. Clinician-inserted and patient-inserted prostheses fulfill the same purposes: keep the fistula open, prevent food and liquid from passing from the esophagus into the trachea, and act as a shunt through which exhaled air enters the esophagus and activates the sound-generating mechanism, usually the PE junction. Both types of voice prostheses are hollow silicone tubes and are available in various lengths and diameters to securely fit into the TEP. Both clinician-inserted and patient-inserted prostheses comprise a retention collar and a one-way valve. In addition, some include a neck strap, which is located on the tracheal end of the VP and is used to secure the VP onto the neck. The retention collar snaps into place on the esophageal end of the fistula to prevent VP dislodgement and leakage. The one-way valve opens under positive tracheal pressure, diverting the air into the esophagus, and closes by elastic recoil  .
Attention has to be paid to certain important issues, which include candidate dexterity, phonatory effort, party wall thickness, durability, and cost of the prosthesis. An in-dwelling prosthesis is ideal for patients unwilling to change their valve independently. Patients with good phonatory effort with an open puncture tract before insertion of the prosthesis can undergo a trial of higher-resistance durable valves. The length of the fistula or party wall thickness needs to be estimated accurately, to obtain a snug fit for the prosthesis  .
Complications, problems, and solutions: The tracheoesophageal voice success rate following total laryngectomy varies between 70 and 95%. Voice failure after prolonged speech therapy may be either due to TE puncture or prosthesis-related complications/problems or 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. Selection of the most suitable 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 spp. and commensal oral microflora can also cause leakage through the prosthesis. Antifungal treatment can prolong the life span of the prostheses. The long-term use of an antimicrobial agent 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  .
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 to tumor recurrence. Collagen or autologous fat injection 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. 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. 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. 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. This can usually occur if cricopharyngeal myotomy is performed inadequately. The use of Clostridium botulinum, 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. Myotomy is now rarely required and is reserved for circumstances in which the botulinum injection has been ineffective in relieving a spasm  .
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. It also occurs in heavily irradiated patients or in those in whom the surgical closure is 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 weak, breathy TE voice. It occurs as a result of the loss or absence of muscular tone or when the PE lumen is large. 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 has been varied. 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  .
Neoglottis involves suturing the pharyngeal mucosa over the superior end of the transected trachea above the primary tracheostoma and making a permanent stoma in the mucosa. Neoglottis is achieved by a tracheohyoidpexy technique that aims at restoring laryngeal function. Because of these inherent problems, use of the neoglottis has been abandoned by most surgeons  .
The future of reconstructive surgery lies in advances in composite tissue transplantation. Although there has been a considerable amount of research and interest in laryngeal transplantation, it remains a controversial topic with several obstacles impeding large clinical trials. It is a complex procedure that would involve at least anastomosis of the superior thyroid artery, jugular vein, and four nerves (two recurrent and two superior laryngeal nerves). In addition, tracheostomy, gastrostomy, and stenting are required  . The first laryngeal transplant was performed in Cleveland, Ohio, in 1988  . The patient, who underwent laryngectomy for trauma, suffered early acute rejection episodes but later achieved normal speech and swallowing function ([Figure 5])  .
| Conclusion|| |
Voice rehabilitation is one of the most important determinants of the quality of life after total laryngectomy. Recent advances in prosthetic voice devices have made such devices the gold standard for voice rehabilitation. They are thus preferred and used more often than old methods (esophageal speech and artificial larynx). There is ongoing research to find solutions to the most common complications of TEP.
| Acknowledgements|| |
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]