voice tracing

Current Therapies

Speech Generating Devices

Speech generating devices are used for communication by individuals that do not have the ability to speak. These individuals typically have a diagnosis of severe apraxia, aphasia, aphonia, and/or dysarthria, which may be secondary to motor dysfunction, spasticity, tremor, rigidity, or ataxia. Their disability may result from a disease or congenital disorder, such as cerebral palsy, stroke, progressive amyotrophic lateral sclerosis, multiple sclerosis, muscular dystrophy, traumatic or congenital quadriplegia, or traumatic brain injury.

Speech Generating Devices or augementative communication devices enable an individul to communicate more effectively with others. A device assists an individual in communicating through printed words, speech or voice output, pictures, or any combination of these. Devices range from having basic components and performing fundamental language functions to having the ability to perform computer-like functions and control household appliances. SGDs are designed to be used as a supplementary mode of communication to augment existing communication strategies and can be configured or customized to address most communication needs.

There are a variety of communication devices available. Devices can have a single message or multiple messages. Devices are categorizes based on the following features:

  • Speech Output- Digitized (recorded human speech) or Synthesized (electronic conversion of text into speech).
  • Message Type- Prerecorded (messages that are stored) or Message Formulation (can spontaneously create novel messages).
  • Access Method- Direct Physical Contact with Device or Multiple Access Methods (e.g., switch, mouse, joystick, etc.).
  • Message Formulation Technique- Spelling only or Spelling and Other Methods.

Additionally, devices have different selection sets (dynamic, static or both). Dynamic sets are similar to a computer monitor. The selection set or level changes automatically on a dynamic screen as the user makes choices. Static sets have fixed symbol choices or levels that can be manually changed. Most static sets Static sets usually have a group of letters, pictures and/or words on an overlay that is inserted or attached to the device.

Specialized switches are used with the scanning feature on some devices. Specialized switches can be activated by almost any body part or body action. Some examples of specialized switches include sip and puff, myoelectrical, mercury, eye blink, and vibration.


About half the laryngectomy population uses hand-held electrolarynges (EL) as their primary means of communication. An electrolarynx is an electronic vibrating device that is placed against the neck and creates vibration in the mouth that the speaker then articulates into speech. It is a medical device used to produce clearer speech by those who have lost their original voicebox, usually due to cancer of the larynx. There are several such battery powered devices on the market. With one type of unit, you place it against your throat, push a button, and the machine transmits a vibration noise to your throat which you then form into words and sounds with your lips, teeth, and tongue. With the second type, the vibration sound is transmitted directly into your mouth via a small tube.

Most artificial or electrolarynges are made to be used by holding them against the outside of the neck, but some have oral adapters, particularly useful when the throat is swollen or sensitive. Some of these brand names are Servox, TruTone, Romet, Optivox, Nu-Vois, Denrick and Solatone.

Currently available EL devices produce speech that sounds non-human (mechanical, robotic, monotone), has reduced intelligibility and loudness, and draws undesirable attention to the user. The poor quality of EL speech has been traced to limitations in performance of current EL sound generating transducers, and to the loss of the fine control of pitch, amplitude, and voice onset and offset timing that is normally provided by the laryngeal mechanism.

The advantages of the electrolarynx are it's short learning time, ability to use immediately postop, and relative availability and low cost.

Voice Prosthesis

Voice prosthesis allows the production of the much preferred "tracheo/esophageal" (TE) voice after total laryngectomy. In this method, a channel (called a “voice-fistula”) is made through the wall between the windpipe and the gullet (the TE-wall). Voice functions are generally replaced with a voice prothesis placed in the tracheo-esophageal puncture created by the surgeon. The voice prosthesis vibrates the esophageal tissue in lieu of the larynx.

When you exhale while covering the stoma at the same time, the air from the lungs will be pushed through this channel into the gullet where an esophageal voice is produced. To prevent food and liquids from passing into the lungs via the fistula, a voice prosthesis is inserted. A voice prosthesis is a one-way valve that allows exhaled air to pass freely. The valve closes during swallowing to prevent food and liquids from entering the lungs.The main benefit of this technique is that you can get your new voice fairly soon after surgery. A secondary benefit is your ability to control the volume, intonation and length of sentences.

The Provox voice prosthesis is made of soft silicon and it can stay in place for a long time. The Provox voice prosthesis has a unique, strong construction with a low-resistance valve molded in one piece with the prosthesis. The valve seals against a stabilizing, non-deformable blue ring made of hard plastic. The prosthesis has stable flanges to keep it in place. The Provox voice prosthesis can be inserted at the time of surgery, some weeks after surgery or whenever convenient.

Talking with a voice prosthesis is easy and requires little training. Just like normal speech, you use the air you breath out. Simply cover the stoma with your finger and gently exhale. The air is led through the voice prosthesis into the gullet where the wall vibrates and creates an esophageal voice. You can vary your new TE voice, both in loudness and pitch, in the same manner as a normal voice, by changing the flow of air as you exhale.

             Static SGD

         Dynamic SGD

          How Electrolarynx works

     Assorted Electrolarynx devices

Voice prosthesis inserted in the    trachea-esophagus channel

      Provox voice Prosthesis



large apple