LARYNGECTOMY FAQ'S
(Dr. Philip Doyle, Ph.D. - U. of Western Ontario, Canada)

How is Voice Produced Following Total Laryngectomy?

Voice and speech production after laryngectomy requires that an alaryngeal source can be produced. Two general categories of options (intrinsic and extrinsic) exist for post-laryngectomy speech rehabilitation. Regardless of whether the source is intrinsic or extrinsic, this voiced signal can then be articulated in the upper vocal tract into speech. However, significant changes in the parameters of voice are well documented. Phonation, articulation, resonance, prosody, intelligibility have been shown to change dramatically following laryngectomy. When an electronic source, or electrolarynx is used, changes are more apparent because of the mechanical nature of the alaryngeal source.

Alaryngeal speech may be subgrouped into methods that are intrinsic and those that are extrinsic. These terms relate directly to the issue of what constitutes the alaryngeal voice source following laryngectomy, and how the source is introduced into the vocal tract. Intrinsic methods utilize anatomical tissues for a psuedoglottis. In most instances this intrinsic alaryngeal voice source is the esophagus. But two other intrinsic methods have been reported in the literature, buccal and pharyngeal sources. Neither of these sources are believed to be sufficient to meet the needs of functional alaryngeal communication.

These two methods of alaryngeal speech rely on the ability of the individual to get air into the esophagus and then move this air across the upper tissue of the esophagus which creates vibration. This esophageal voice source then moves up into the vocal tract where it is articulated into speech. While both esophageal and TE speech use the upper esophageal region as a vicarious voice source, the method of how air is moved into the esophageal reservoir is quite different. In esophageal speech, air in the oral cavity is moved into the esophagus after specific types of maneuvers. In TE speech, the patient uses a small prosthetic device that is able to redirect tracheal air into the esophagus.

The electronic artificial larynx, or electrolarynx, is a mechanical device that provides an alaryngeal sound source to the laryngectomized individual. Two basic types of devices are commonly used today. These device are categorized by how the alaryngeal voice source is introduced into the vocal tract. The first type of electrolarynx is called a transcervical device because the vibratory head of the device is place on the external neck. Thus, the vibrated electronic source is passed through tissues of the neck where the source signal is resonated in the vocal tract and speech is produced. The second type of device is called a transoral or intraoral device because the vibratory source is passed into the oral cavity via a tube. Once this source is in the oral cavity, it can be articulated into the sounds of speech.