Functional characteristics of a new electrolarynx "Evada" having a force sensing resistor sensor

Design and Preliminary Evaluation of Electrolarynx With F0 Control Based on Capacitive Touch Technology

An electrolarynx (EL) is one of the most popular voice rehabilitation technologies used after laryngectomy. However, most ELs generate monotonic EL speech, which has been shown to create a particular deficit in speech intelligibility, especially for Chinese Mandarin (Mandarin). Mandarin is a tonal language that makes lexical distinctions using variations in tone. Our purpose is to design an EL that can produce the four Mandarin tones, and to evaluate its performance. We designed a fundamental frequency (F0) control method for Mandarin EL speech and manufactured a touch-controlled electrolarynx (T-EL) prototype. Using monosyllables, disyllabic words, and frequently used phrases, we evaluated speech produced with a T-EL, as well as with monotone (M-EL) and variable-frequency modes (P-EL) of a commercially available TruTone EL. A male native Mandarin speaker with laryngectomy volunteered to be the speaker. Results show that the normal speech pitch contours of the four Mandarin tones were most closely matched by the characteristics produced with T-EL. The statistical accuracy of the T-EL's tone and word perception was significantly higher than that of the other EL types. Moreover, the confusion matrix indicates that the listeners could correctly identify the tones of monosyllables and disyllabic words in T-EL speech. Accurate tone judgment can improve the intelligibility of EL speech in Mandarin. The mean opinion score was used to evaluate the listeners' acceptability of EL speech. The scores of the T-EL and M-EL were very close, and the score of the P-EL was significantly lower than that of the other two ELs. However, the results from a single speaker cannot provide sufficient data to conclude which EL has a higher acceptability. The evaluation of multiple EL speakers with different EL types at difference levels of proficiency should be studied in future research.

The electrolarynx: voice restoration after total laryngectomy

The ability to speak and communicate with one’s voice is a unique human characteristic and is fundamental to many activities of daily living, such as talking on the phone and speaking to loved ones. When the larynx is removed during a total laryngectomy (TL), loss of voice can lead to a devastating decrease in a patient’s quality of life, and precipitate significant frustration over their inability to communicate with others effectively. Over the past 50 years there have been many advances in techniques of voice restoration after TL. Currently, there are three main methods of voice restoration: the electrolarynx, esophageal speech, and tracheoesophageal speech through a tracheoesophageal puncture (TEP) with voice prosthesis. Although TEP voice is the current gold standard for vocal rehabilitation, a significant minority of patients cannot use or obtain TEP speech for various reasons. As such, the electrolarynx is a viable and useful alternative for these patients. This article will focus on voice restoration using an electrolarynx with the following objectives: 1) To provide an understanding of the importance of voice restoration after total laryngectomy. 2) To discuss how the electrolarynx may be used to restore voice following total laryngectomy. 3) To outline some of the current electrolarynx devices available, including their mechanism of action and limitations. 4) To compare pros and cons of electrolaryngeal speech to TEP and esophageal speech.

Development and evaluation of wheel-controlled pitch-adjustable electrolarynx

Tone is important in tonal languages, especially in Mandarin. However, there is presently no commercially available electrolarynx (EL) for laryngectomized Mandarin speakers. Moreover, few studies have focused on this area. Our purpose is to design an EL that produces the four Mandarin tones and to evaluate its performance. We designed a wheel-controlled pitch-adjustable EL and manufactured a prototype (Wheel-EL). Using monosyllables, disyllabic segments, and frequently used phrases, we evaluated speech produced by Wheel-EL and by monotone (M-TruTone) and variable-frequency modes (V-TruTone) of the commercially available TruTone EL. The pitch contours of the high-level (HL), middle-rising (MR), and falling-rising (FR) tones produced by Wheel-EL most closely matched the natural speech characteristics of a native speaker. However, redundant sounds were generated in the high-falling (HF) tone. The statistical accuracy of Wheel-EL's tone and word perception was significantly higher than that of other EL types. However, no significant differences existed in acceptability among the three EL speech types. Wheel-EL produces better HL, MR, and FR tones in Mandarin than either M-TruTone or V-TruTone. Nevertheless, redundant sounds affect HF phonation. Accurate tone judgment can improve the intelligibility of EL speech in Mandarin but has no obvious effect on acceptability.

Development and perceptual evaluation of amplitude-based F0 control in electrolarynx speech

PURPOSE

Current electrolarynx (EL) devices produce a mechanical speech quality that has been largely attributed to the lack of natural fundamental frequency (F0) variation. In order to improve the quality of EL speech, in the present study the authors aimed to develop and evaluate an automatic F0 control scheme, in which F0 was modulated based on variations in the root-mean-square (RMS) amplitude of the EL speech signal.

METHOD

Recordings of declarative sentences produced by 2 male participants before and after total laryngectomy were used to develop procedures for calculating F0 contours for EL speech. Specifically, the positive linear relationship between F0 and RMS amplitude observed in pre-laryngectomy speech was used as the basis for generating an F0 contour based on the amplitude variation of EL speech. An analysis-by-synthesis approach was used to modify the F0 contour, and a perceptual experiment was conducted to examine its impact on the quality of the EL speech.

RESULTS

The results of perceptual experiments showed that modulating the F0 of EL speech using a linear relationship between amplitude and frequency made it significantly more natural sounding than EL speech with constant F0.

CONCLUSIONS

The current study provides preliminary support for amplitude-based control of F0 in EL speech.

A remotely powered and wirelessly controlled intraoral electrolarynx

Electrolarynx devices have restored the voice of many who would otherwise be unable to speak. Current intraoral electrolarynx devices either have unappealing transoral tubes or are too large to easily fit in the mouth. We introduce a novel, remotely powered and wirelessly controlled intraoral electrolarynx that addresses these issues. Due to its size, the intraoral part of the device is easily embedded into a maxillary denture or a dental appliance. Characteristics of the device, including operating distance, positional sensitivity and orientation sensitivity were investigated. The results show that the device can be remotely powered and wirelessly controlled for use as an intraoral electrolarynx. Speech intelligibility of the device is not presented, but will be in future studies.

Training effects on speech production using a hands-free electromyographically controlled electrolarynx

PURPOSE

The electrolarynx (EL) is a widely used device for alaryngeal speech, but it requires manual operation and produces voice that typically has a constant fundamental frequency. An electromyographically controlled EL (EMG-EL) was designed and implemented to provide hands-free control with dynamic pitch modulation.

METHOD

Three participants who underwent total laryngectomy surgery and 4 participants with normal voice were trained to produce EMG-EL speech through a multiple-baseline, successive-stage protocol. Baseline performance was established through 3 testing probes, followed by multiple hour-long training sessions.

RESULTS

At the end of the training, all participants learned to initiate, sustain, and terminate EMG-EL activation in correspondence with articulation, and most were able to modulate the pitch to produce intonational contrasts. After completing the testing/training protocol, 1 of the 3 participants who underwent total laryngectomy was encouraged to independently use the EMG-EL at his residence. This participant sustained his performance for an additional 6 weeks and also used the EMG-EL successfully to communicate over the phone.

CONCLUSIONS

Our findings suggest that some participants with laryngectomies and vocally normal individuals can learn to produce hands-free speech using the EMG-EL device within a few hours and that significant additional gains in device control (particularly pitch modulation) are attainable through subsequent training sessions.

Design and fabrication of a new electrolarynx and voice amplifier for laryngectomees

A Laryngectomee is a person whose vocal cords i.e. voice box is surgically removed owing to cancer or due to automobile accidents, burns or trauma. The patient, therefore permanently loses the ability to speak normally. An Electrolarynx is an electronic speech aid that enables the Laryngectomee to communicate with other people as quickly as possible after the successful removal of the larynx. A neck type Electrolarynx has been designed. Earlier designs could not alter frequency and intensity simultaneously during conversation. The Electrolarynx developed can control both frequency and intensity simultaneously during conversation. The device has been tested on the patient and found to be very effective. A portable, pocket size, battery powered voice amplifier (PA system) has also been developed which uses an electret condenser microphone as the input. The voice amplifier developed is a two stage amplifier which uses a preamplifier stage and a power amplifier stage. The output of the power amplifier is connected to a speaker. The device is being used by the patient and found to be very useful.

Comunicação oral de laringectomizados com prótese traqueoesofágica: análise comparativa pré e pós-treino

TEMA: treinamento fonoaudiológico para pacientes laringectomizados totais com prótese traqueoesofágica. OBJETIVO: comparar a qualidade da comunicação oral de pacientes laringectomizados, com prótese traqueoesofágica antes e depois de treinamento fonoaudiológico. MÉTODO: foram analisadas amostras de voz e fala de 17 pacientes laringectomizados, antes e depois de treinamento de voz e fala. As amostras pré e pós-treino foram misturadas ao acaso e apresentadas a fonoaudiólogos para avaliação. RESULTADOS: observada melhora significativa (Teste da Binomial) no conjunto dos aspectos avaliados. CONCLUSÃO: pode-se considerar que o treino proposto melhorou os padrões de fala inclusive a melodia e do canto.

Features of Listeners Affecting the Perceptions of Mandarin Electrolaryngeal Speech

The effect of age and gender of listeners on the perceptions of Mandarin electrolaryngeal speech was investigated. Sixty males and 40 females were categorized into five age groups (20-29, 30-39, 40-49, 50-59, and 60-70 years), who were regarded as naive listeners for having no experience with electrolaryngeal speech. They were instructed to score acceptability of a passage and intelligibility of isolated words and embedded words. The results revealed no gender effects but significant age effects on the perceptual evaluation. It was more difficult for the 50-59 and 60-70 groups to understand electrolaryngeal speech. The results were also analyzed for tonal and segmental errors, and errors of tone alone were found to occur more often than segmental errors. In addition, a preliminary study was presented for the perceptions of the four Mandarin tones. Higher percent correct identification was found for the high-level tone compared to the other three tones.