Voice prosthesis

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Voice prosthesis Voice prosthesis.jpg
Voice prosthesis

A voice prosthesis (plural prostheses) is an artificial device, usually made of silicone that is used in conjunction with voice therapy to help laryngectomized patients to speak. During a total laryngectomy, the entire voice box (larynx) is removed and the windpipe (trachea) and food pipe (esophagus) are separated from each other. During this operation an opening between the food pipe and the windpipe can be created (primary puncture). This opening can also be created at a later time (secondary puncture). This opening is called a tracheo-esophageal puncture (TE puncture). The voice prosthesis is placed in this opening. Then, it becomes possible to speak by occluding the stoma and blowing the air from the lungs through the inside of the voice prosthesis and through the throat, creating a voice sound, which is called tracheo-esophageal speech. The back end of the prosthesis sits at the food pipe. To avoid food, drinks, or saliva from coming through the prosthesis and into the lungs, the prosthesis has a small flap at the back. There are two ways of inserting the voice prosthesis: through the mouth and throat (retrograde manner) with the help of a guide wire, or directly through the tracheostoma (anterograde) manner. Nowadays, most voice prosthesis are placed anterograde, through the stoma.

Contents

History

There are two lines of development on behalf of giving a voice to patients being laryngectomized.

Artificial larynx

In 1869 the first artificial voice box (larynx) was built by Czermak. [1] In 1873 Theodor Billroth made a total laryngectomy (in steps) and implanted an artificial voice box. [1] [2] A new development, using modern materials, took place in France by Debry. [3]

Voice prosthesis

In 1972 the very first voice prosthesis for voice rehabilitation after total laryngectomy was described in an article in Polish by Mozolewski. [4] Since then, many efforts have taken place in this area of rehabilitation. There are several manufacturers that have voice prosthesis in their product portfolio, e.g. Blom-Singer®, Adeva®, Eska®, MediTop®, Heimomed®. The internationally most widely used are devices made by InHealth Technologies and Atos Medical. In 1980, the first commercially available prosthesis was introduced by Singer and Blom: [5] the ‘Blom-Singer® Duckbill’, a 16 French diameter, non-flanged device that the patient could remove, clean and replace him- or herself (non-indwelling). The first indwelling voice prosthesis (Groningen Voice Prostheis) was described in 1984. [6] And in 1990, the first Provox® voice prosthesis, manufactured by Atos Medical, was introduced to the market, [7] followed by the Provox®2 in 1997, [8] the Provox® ActiValve™ in 2003, [9] and the non-indwelling Provox® NID™ in 2005. [10] 1994, the Blom-Singer® Classic™ Indwelling Voice Prostheses [11] was introduced to the market. Like the Blom-Singer® Advantage® Indwelling Voice Prosthesis it is only inserted or replaced by medical professionals, such as speech pathologists or physicians. In 2009 the third generation Provox® Vega [12] with SmartInserter™ [13] was introduced. [14]

Non-indwelling and indwelling voice prostheses

The two main categories voice prosthesis can be divided into are ‘non-indwelling’ and ‘indwelling’ voice prostheses. ‘Non-indwelling’ voice prostheses can be replaced by the patients themselves, [10] whereas ‘indwelling’ prostheses have to be replaced by a medical professional. A non-indwelling voice prosthesis has a safety strap and may also have a string with a special safety medallion that is too wide to fall into the tracheostoma. It comes in different sizes and lengths and often has a noticeable color, e.g. blue or white to enhance visibility for self-replacement and maintenance. Disadvantages of the non-indwelling prosthesis are a certain amount of risk when inserting them by oneself and the devices have a shorter lifetime and need to be changed more often. In general it takes some practice to insert the prosthesis and the ability to take excellent care of the device. Indwelling devices have sturdier flanges and can only be replaced by a medical professional. The safety strap is cut off after insertion. The choice between ‘non-indwelling’ and ‘indwelling’ devices is really individual, depending on physical condition, maintenance and cost and can be alternated over a period of time to find out which one is most suitable.

Design of voice prostheses

The general design of voice prosthesis is quite consistent, even though there are unique characteristics. A voice prosthesis has retaining flanges at each end, the ‘tracheal flange’ and ‘esophageal flange’. Those flanges can vary in size and rigidity, e.g. indwelling prostheses have larger and more rigid flanges for stability and facilitate long-term placement. The flange near the food pipe (esophageal flange) is more rigid than the tracheal flange, near the windpipe. The one-way valve can be molded in one piece with the prosthesis and is often supported by a fluoroplastic valve seat (a colored ring that is tightly secured into the shaft of the prosthesis, adding rigidity and which is radiopaque). All voice prostheses have a safety strap, which is cut off in indwelling devices after the prosthesis is put in place; in non-indwelling devices the strap is not removed and is taped to the neck. A voice prosthesis has a one-way valve near the esophageal flange that enables pulmonary air to pass into the esophagus and pharynx for sound production and prevents content from the food pipe, such as liquids or saliva, from entering the trachea.

Properties of voice prostheses

Material

A voice prosthesis is usually made of medical grade silicone rubber. The valve flap and valve seat may be made out of silicone, fluoroplastic, or may be treated with SilverOxide.

Sizes

The size of a voice prosthesis varies in length, depending on the thickness of the wall between the foodpipe and the windpipe and thereby the length of the TE puncture. The according length of the voice prosthesis ranges usually between 4 and 22 mm. Another parameter is the outer diameter of the shaft of the voice prosthesis, ranging from 16-22.5  French. Which outer diameter is used is decided by the clinician and/or the patient and is most often a matter of personal preference. Studies have shown that a larger outer diameter of the voice prosthesis allows better airflow and thereby requires less effort to speak which has a positive effect on the overall voice quality. [15]

Problem-solving voice prosthesis for strong candida accumulation

There are even special, problem-solving voice prosthesis, e.g. for laryngectomized patients with very short device life times (less than 4 to 8 weeks) of their current prosthesis. Those extremely short device life times may be caused by excessive candida growth, so that the valve of the prosthesis does not close properly anymore and content from the food pipe leaks through the voice prosthesis into the windpipe. Some of these prostheses have a magnet within the valve that strengthens the closure, others are made of silver oxide silicone to reduce biofilm formation on the valve or use two valves, in case of defect of the esophageal valve, the other valve would seal. In patients with a short device life, the use of a voice prosthesis with supporting magnets in the valve seat and valve flap has been proven to be cost effective. [16]

Cleaning

It is important to clean the voice prosthesis regularly, as the silicone material is exposed to yeast (candida) and bacteria in the food pipe, which is normally present in these areas. [17] If yeast begins growing on or in the area of the valve flap of the voice prosthesis, it may not close well enough anymore. When this happens fluid starts to leak into the windpipe when eating or drinking.

Brushing

The inside of the voice prosthesis is usually cleaned with a brush, which removes food and mucus. It is recommended that the patient cleans the voice prosthesis regularly to keeps it open for speech and improve the device lifetime.

Flushing

It is also possible to flush the inside of the voice prosthesis with water or air. [18] Usually this is done in combination with brushing.

Leakage

A voice prosthesis has to be replaced regularly, because after a certain time, the valve flap of the voice prosthesis does not close properly anymore, due to yeast and other natural sediments. This causes leakage of saliva or drinks, which enters the wind pipe and makes the person concerned cough. If not resolved by cleaning the voice prosthesis, this is a sign that the voice prosthesis must be changed. If that is not possible right away, there are special plugs that can block the leakage. The patient can insert this plug him-/ herself before eating or drinking and remove it again afterwards, as speaking with the plug in place is usually not possible.

Device lifetime

The device lifetime can range from a couple of weeks up to two years, depending on individual circumstances. [19] The lifetime is influenced by daily food intake, especially dairy products, [20] but also radiotherapy [A 1] and GERD (Gastro Esophageal Reflux Disease) affects the voice prosthesis and its lifetime. [21] The cause of the prothesis' life time end is mostly leakage, but also growing of fistulae, granulation tissue, increasing valve's opening pressure and prothesis' loss [22]

Voice quality and speaking effort

The voice quality when speaking with a voice prosthesis is influenced by pulmonary support, airflow resistance of the voice prosthesis, and airflow resistance of the new voice source. [23] Although the voice prosthesis is only responsible for part of the total resistance – the neoglottis is responsible for the other part – favorable airflow characteristics are expected to enable the laryngectomized patient to speak with less effort. [12] The voice sounds rather clear though not very loud as samples show. [24]

Voice prosthesis and HME

An individual combination of voice prosthesis, heat and moisture exchanger after laryngectomy and attachment is important for good speech and pulmonary rehabilitation. [25] The HME sometimes is combined with free-hands-switch and virus and bacteria filter. [26]

Annotations

  1. A Free University of Berlin study shows a different result

Related Research Articles

Prosthesis Artificial device that replaces a missing body part

In medicine, a prosthesis or prosthetic implant is an artificial device that replaces a missing body part, which may be lost through trauma, disease, or a condition present at birth. Prostheses are intended to restore the normal functions of the missing body part. Amputee rehabilitation is primarily coordinated by a physiatrist as part of an inter-disciplinary team consisting of physiatrists, prosthetists, nurses, physical therapists, and occupational therapists. Prostheses can be created by hand or with computer-aided design (CAD), a software interface that helps creators design and analyze the creation with computer-generated 2-D and 3-D graphics as well as analysis and optimization tools.

Gastroesophageal reflux disease Medical condition

Gastroesophageal reflux disease (GERD), is a chronic condition in which stomach contents rise up into the esophagus, resulting in either symptoms or complications. Symptoms include the taste of acid in the back of the mouth, heartburn, bad breath, chest pain, regurgitation, breathing problems, and wearing away of the teeth. Complications include esophagitis, esophageal stricture, and Barrett's esophagus.

Breast augmentation Surgical procedure

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Esophageal speech, also known as esophageal voice, is an airstream mechanism for speech that involves oscillation of the esophagus. This contrasts with traditional laryngeal speech, which involves oscillation of the vocal folds. In esophageal speech, pressurized air is injected into the upper esophagus and then released in a controlled manner to create the airstream necessary for speech. Esophageal speech is a learned skill that requires speech training and much practice. On average it takes 6 months to a year to learn this form of speech. Because of the high level of difficulty in learning esophageal speech, some patients are unable to master the skill.

Laryngectomy

Laryngectomy is the removal of the larynx and separation of the airway from the mouth, nose and esophagus. In a total laryngectomy, the entire larynx is removed. In a partial laryngectomy, only a portion of the larynx is removed. Following the procedure, the person breathes through an opening in the neck known as a stoma. This procedure is usually performed by an ENT surgeon in cases of laryngeal cancer. Many cases of laryngeal cancer are treated with more conservative methods. A laryngectomy is performed when these treatments fail to conserve the larynx or when the cancer has progressed such that normal functioning would be prevented. Laryngectomies are also performed on individuals with other types of head and neck cancer. Post-laryngectomy rehabilitation includes voice restoration, oral feeding and more recently, smell and taste rehabilitation. An individual's quality of life can be affected post-surgery.

Osseointegration is the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant. A more recent definition defines osseointegration as "functional ankylosis ", where new bone is laid down directly on the implant surface and the implant exhibits mechanical stability. Osseointegration has enhanced the science of medical bone and joint replacement techniques as well as dental implants and improving prosthetics for amputees.

Implant (medicine) Device surgically placed within the body for medical purposes

An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. Medical implants are man-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents.

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An electrolarynx, sometimes referred to as a "throat back", is a medical device about the size of a small electric razor used to produce clearer speech by those people who have lost their voice box, usually due to cancer of the larynx. The most common device is a handheld, battery-operated device pressed against the skin under the mandible which produces vibrations to allow speech; other variations include a device similar to the "talk box" electronic music device, which delivers the basis of the speech sound via a tube placed in the mouth. Earlier non-electric devices were called mechanical larynxes. Along with developing esophageal voice, using a speech synthesizer, or undergoing a surgical procedure, the electrolarynx serves as a mode of speech recovery for laryngectomy patients.

Breast implant Prosthesis used to change the size, shape, and contour of a persons breast

A breast implant is a prosthesis used to change the size, shape, and contour of a person's breast. In reconstructive plastic surgery, breast implants can be placed to restore a natural looking breast following a mastectomy, to correct congenital defects and deformities of the chest wall or, cosmetically, to enlarge the appearance of the breast through breast augmentation surgery.

Penile implant Medical device

A penile implant is an implanted device intended for the treatment of Erectile dysfunction, Peyronie's disease, ischemic Priapism, deformity and any traumatic injury of the penis, and for phalloplasty in men or phalloplasty and metoidioplasty in female-to-male gender reassignment surgery. Men also opt for penile implants for aesthetic purposes. Men’s satisfaction and sexual function is influenced by discomfort over genital size which leads to seek surgical and non-surgical solutions for penis alteration. Although there are many distinct types of implants, most fall into one of two categories: malleable and inflatable transplants.

A tracheo-esophageal puncture is a surgically created hole between the trachea (windpipe) and the esophagus in a person who has had a total laryngectomy, a surgery where the larynx is removed. The purpose of the puncture is to restore a person’s ability to speak after the vocal cords have been removed. This involves creation of a fistula between trachea and oesophagus, puncturing the short segment of tissue or “common wall” that typically separates these two structures. A voice prosthesis is inserted into this puncture. The prosthesis keeps food out of the trachea but lets air into the esophagus for oesophageal speech.

Nose prosthesis

Nose prosthesis is a craniofacial prosthesis for someone who no longer has their original nose. Nose prostheses are designed by anaplastologists who have their patients referred to them by ear, nose, and throat doctors and plastic surgeons. Unlike the more common nasal operation called a rhinoplasty, total reconstruction of the nose using existing tissue, prosthetic nose implantation requires the nose to be made completely from synthetic material; prior to getting a nose prosthesis, the original nose is usually left partially intact, so a rhinectomy, surgical removal of the nose, has to be performed before a prosthetic nose can be used. One of the biggest challenges for anaplastologists in constructing a nose prosthesis is finding the right material to use for the nose, as it's a complex organ with several distinct functions and a unique structure. The major functions of the nose include the sense of smell (olfaction), filtered breathing, and alteration of speech. All of these tasks can be completed due to the nose’s network of bones, cartilage, and muscle, which also helps to keep the nose stable on the face. Although there are currently usable prosthetic noses, they only have temporary functionality. Advancements in areas such as 3D-printing have medical professionals hoping to create noses that are as efficient as the real ones.

Eric M. Genden, MD, MHCA, FACS is a United States head and neck cancer surgeon at the Icahn School of Medicine at Mount Sinai and Mount Sinai Health System in New York City. where he serves as the Isidore Friesner Professor and Chairman of Otolaryngology–Head and Neck Surgery and Professor of Neurosurgery and Immunology. According to his biography at Mount Sinai, Genden's professional titles also include Senior Associate Dean for Clinical Affairs, He is Executive Vice President of Ambulatory Surgery, and Director of the Head and Neck Institute at the Mount Sinai Health System.

Roentgen stereophotogrammetry (RSA) is a highly accurate technique for the assessment of three-dimensional migration and micromotion of a joint replacement prosthesis relative to the bone it is attached to. It was introduced in 1974 by Göran Selvik.

Voice therapy

Voice therapy consists of techniques and procedures that target vocal parameters, such as vocal fold closure, pitch, volume, and quality. This therapy is provided by speech-language pathologists and is primarily used to aid in the management of voice disorders, or for altering the overall quality of voice, as in the case of transgender voice therapy. Vocal pedagogy is a related field to alter voice for the purpose of singing. Voice therapy may also serve to teach preventive measures such as vocal hygiene and other safe speaking or singing practices.

Heat and moisture exchanger

Heat and Moisture Exchangers (HME) are devices used in mechanically ventilated patients intended to help prevent complications due to "drying of the respiratory mucosa, such as mucus plugging and endotracheal tube (ETT) occlusion." HMEs are one type of commercial humidification system, which also include non-heated-wire humidifiers and heated-wire humidifiers.

Heat and moisture exchanger after laryngectomy

Heat and moisture exchangers (HME) are used after laryngectomy to help reduce breathing restrictions and compensate nasal functions.

Nipple prosthesis

Nipple/Areola prostheses are made of silicone by breast prosthesis manufacturers and anaplastologists for breast cancer survivors who were treated for breast cancer with a mastectomy. Prostheses can be worn weeks after a mastectomy, breast reconstruction, or even nipple reconstruction. As an inexpensive and convenient alternative to surgery, patients may choose to wear them anytime during treatment. Patients who ultimately find nipple prostheses thought that they should be informed of them during the consultation prior to mastectomy.

Claude-Henri Chouard

Claude-Henri Chouard is a French surgeon born on 3 July 1931 in the 15th arrondissement of Paris, this Otologist has been a full member of the Académie Nationale de Médecine since 1999. He was director of the AP-HP Laboratory of Auditory Prosthesis and director of the ENT Research Laboratory at Paris-Saint-Antoine University Hospital from 1967 to 2001. He was also head of the institution's ENT Department from 1978 to 1998. In 1982, he was elected a member of the International Collegium ORL-AS. He achieved worldwide recognition in the late 1970s thanks to the work completed by his Paris laboratory's multidisciplinary team on the multichannel cochlear implant. This implanted electronic hearing device was developed at Saint-Antoine and alleviates bilateral total deafness. When implanted early in young children, it can also help overcome the spoken language problems associated with deafness.

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