Acoustical aspects of vocal function following radiotherapy for early T1a laryngeal cancer.

We evaluated acoustic voice characteristics of 18 male patients undergoing radiotherapy. The subjects were seen for voice assessment preradiotherapy and at 1 month, 3 months, 6 months, and 1 year following radiotherapy. A multidimensional voice analysis computer program (IVANS, Avaaz Innovations, 1998) was employed to evaluate measures of traditional frequency and amplitude perturbation as well as time-based and linear prediction (LP) modeled "noise" parameters of the acoustic output in conjunction with perceptual judgments of overall vocal quality. The results indicate vocal deterioration of vocal function immediately following radiotherapy with gradual and significant improvement in acoustic and perceptual features over 9 to 12 months following the radiation treatment. Measures of glottal noise demonstrated higher sensitivity than frequency-based measures of voice perturbation, and with more consistent, less variable changes in acoustical voice output from the preradiation to the 12 month postradiation periods. Future research evaluating vowel type and acoustic perturbation measures with a larger sample of subjects over a longer time period seems warranted.

Vocal function following radiation for non-laryngeal versus laryngeal tumors of the head and neck.

OBJECTIVE: The larynx may receive high doses of radiation even in the absence of disease. Preliminary investigation has provided evidence that significant voice alterations exist in patients who received radiotherapy (RT) for non-laryngeal tumors of the head and neck. This study evaluates subjective and objective parameters of vocal function in this patient population compared with a control group of patients irradiated for early glottic tumors. STUDY DESIGN: Retrospective cohort study. METHODS: Vocal function in patients irradiated for non-laryngeal and early glottic tumors was assessed in a comprehensive manner and compared. Microanalytical and macroanalytical acoustic analyses, aerodynamic measurements, and videostroboscopy were performed on vowel production data. The Voice Handicap Index was administered for self-assessment of voice quality. All subjects were male, smokers, and greater than 12 months post-RT. RESULTS: Seventeen patients with non-laryngeal tumors and 13 patients with early glottic tumors were evaluated. Microanalytical acoustic parameters were worse for 75% (6 of 8) of the acoustic measures of vowel production in the non-laryngeal group. These include jitter, relative amplitude perturbation, amplitude perturbation quotient, normalized noise energy, pitch amplitude, and spectral flatness ratio. Macroanalytical acoustic analyses revealed no difference in fundamental frequency but numerically smaller phonational frequency range in the non-laryngeal group. All aerodynamic measures, including mean phonation time, mean airflow, and vocal fold diadochokinetic rate, were decreased in the non-laryngeal group. Videostroboscopy demonstrated increased supraglottic activity in the non-laryngeal group. Voice handicap was significantly greater in the non-laryngeal group. CONCLUSIONS: When compared with patients receiving RT for early glottic tumors, there is objective and subjective evidence of vocal dysfunction in patients treated with wide-field RT for non-laryngeal tumors.

Effects of head and neck radiation therapy on vocal function.

OBJECTIVE: Radiotherapy (RT) is used to treat a variety of head and neck malignancies. The larynx may receive high radiation doses even in the absence of disease. The effects of RT on the nondiseased larynx are unknown. This study will evaluate subjective and objective parameters of vocal function in patients treated with RT for nonlaryngeal malignancies. DESIGN: Cross-sectional observational study. METHODS: Videostroboscopic, aerodynamic, and acoustic analyses were performed. Results were compared to age- and gender-matched controls. Self-assessment of voice quality was measured using the Voice Handicap Index. RESULTS: A majority of patients demonstrated increased supraglottal activity (i.e., ventricular fold constriction) during stroboscopic evaluation. Significant differences compared to normative data were found in many aerodynamic and acoustic parameters. A substantial proportion (27%) of patients reported significant voice handicap. Younger patients reported greater handicap, and voice quality was worse with time. CONCLUSIONS: Significant objective and subjective changes in vocal function occur in patients radiated for nonlaryngeal head and neck malignancies. Young patients may have the worst impact, and vocal dysfunction may increase with time. A prospective study of this patient population should include a baseline voice quality assessment.

A prospective study of cognitive impairment in ALS.

OBJECTIVE: To characterize prospectively the cognitive profile in ALS. METHODS: Clinically definite ALS patients (11 men, 2 women), age 39.9 to 74.0 years (mean age, 54.2 +/- 9.6 years; mean disease duration, 21.1 +/- 10.5 months) underwent neuropsychologic, language, and speech testing followed by MR 1H spectroscopy (4 T). Five spousal control subjects completed an identical protocol. Eight ALS patients participated in follow-up studies at a 6-month interval. RESULTS: Relative to control subjects, ALS patients showed mild impairment in word generation, recognition memory (faces), and motor-free visual perception. Bulbar-onset patients showed greater impairment in a number of measures (working memory, problem solving/cognitive flexibility, visual perception, and recognition memory for words and faces), and cognitive impairment appeared more progressive over time. ALS patients demonstrated anomia on a confrontation naming test, with no significant problems following commands or repeating. Speech motor performance scores and intelligibility scores were not significantly different. No significant declines in forced vital capacity, forced expiratory volume, or peak expiratory flow rates were observed. Although normal at initial testing (T1), MR 1H spectroscopy demonstrated a reduction of the N-acetylaspartate/creatine (NAA/Cr) ratio in the nondominant precentral motor strip across the two testing intervals. In contrast, the NAA/Cr ratio obtained from the anterior cingulate gyrus at T1 was already reduced in bulbar-onset patients (p < 0.001), whereas no deficits were observed in limb-onset individuals in the same region. CONCLUSIONS: Bulbar-onset ALS patients with cognitive impairments and neuronal loss in the anterior cingulate gyrus subsequently developed more profound neuropsychological dysfunction whereas both language and speech capabilities remained relatively preserved. Of note, the absence of bulbar signs did not predict an absence of cognitive decline.

Temporal characteristics of velopharyngeal function in children.

OBJECTIVE: This investigation was designed to examine the performance of children with normal speech on temporal aspects of aerodynamic tasks related to velopharyngeal closure. DESIGN: The investigation was a descriptive evaluation of variability in aerodynamic features related to velopharyngeal function during multiple repetitions of the word "hamper." SETTING: Children without speech or velopharyngeal difficulties were seen in an experimental laboratory setting for the evaluation procedures. PARTICIPANTS: Twenty-seven subjects were recruited for the experiment. Three subjects were rejected because of behavioral difficulties, and the remaining 24 subjects were subdivided into 4 groups of 6 children (3 males and 3 females) aged 3, 6, 9, and 12 years. The children, who were from local schools and day care centers, volunteered to participate in the experiment. All of the children had age-appropriate speech, language, and hearing abilities, as determined by screening tests administered by one of the examiners (L.T.). MAIN OUTCOME MEASURES: Mean and variability of pressure-flow measures of peak intraoral air pressure and peak nasal airflow and the temporal measures accompanying each air pressure or airflow pulse were evaluated for the age groups of children examined in the experiment. RESULTS: The aerodynamic procedures employed to evaluate velopharyngeal closure during speech were reliable for use with young children. There was a numerical trend toward decreased duration of the temporal parameters with increasing age. Thus, children demonstrated durational values similar to those previously reported for normal-speaking adults. In general, peak oral air pressure and nasal airflow values were like those of previous investigations and demonstrated low variability across all age groups of children tested. CONCLUSIONS: The data from the present investigation provide a preliminary base for comparison of temporal features of velopharyngeal closure for the aerodynamic evaluation of children with impaired velopharyngeal function.

Dysarthric speech: a comparison of computerized speech recognition and listener intelligibility.

The purpose of this study was to identify and compare the recognition of dysarthric speech by a computerized voice recognition (VR) system and non-hearing-impaired adult listeners. Intelligibility "functions" were obtained for six dysarthric speakers who varied in severity and six age- and gender-matched controls. Speakers produced 70-item word lists over 5 sessions. VR using the IBM VoiceType and perceptual judgment scores were obtained and functions plotted by session. Data indicate that computerized recognition of both dysarthric and nonimpaired speech was characterized by initially steep increases in correct recognition with more gradual increases noted during the second through fifth sessions. Perceptual recognition by non-hearing-impaired adults indicates generally stable intelligibility scores over time. Severity of dysarthria did appear to influence recognition of target stimuli. Implications of these data to the application of computerized VR technology are presented.

Cognition, language, and speech in amyotrophic lateral sclerosis: a review.

Amyotrophic lateral sclerosis (ALS) is a progressive, adult-onset neurodegenerative disorder manifesting as a relentless loss of motor capabilities and, ultimately, death. Traditionally thought to affect solely the lower motor neurons and corticospinal tracts, recent studies suggest that the pathogenic process of ALS is more extensive, involving dysfunction of cortical grey and white matter with clinical correlates of impairment in cognition and language. The impact of speech and motor deficits are discussed in relation to the issues of assessment of cognition and language. Three case studies are presented for illustrative purposes. Finally, direction for future research to investigate cognitive dysfunction in ALS are presented.

Microanalytic acoustical voice characteristics of near-total laryngectomy.

Limited acoustic data are available describing vocal characteristics of individuals after near-total laryngectomy. Computer-based acoustic analyses (FO, jitter, shimmer, signal-to-noise ratio) were performed on vowel samples produced by 20 speakers who underwent near-total laryngectomy. On the basis of data obtained, the subjects who had undergone near-total laryngectomy demonstrated (1) higher than normal and more variable modal fundamental frequency values for sustained vowels; (2) increased frequency (jitter) and amplitude (shimmer) perturbation; and (3) decreased spectral noise (signal-to-noise) components. In addition, speakers who had undergone near-total laryngectomy showed an increased percentage of unvoiced sound production during their vowel productions. The large variability and general aperiodicity of the phonatory signal during vowel production suggests an ineffective laryngeal valving system with overcompensation in attempts to generate effective voice. These findings have implications for designing behavioral therapy programs to improve voice quality in speakers who receive conservation laryngectomy procedures for treatment of laryngeal carcinoma.

Laryngeal airway resistance of older men and women as a function of vocal sound pressure level.

This study examined laryngeal airway resistance (RLAW) in 10 healthy male and 10 female subjects within three age groups (55:0-64:11; 65:0-74:11; and 75:0+ years). A noninvasive procedure (Smitheran & Hixon, 1981) was employed to investigate RLAW at four vocal sound pressure levels (SPL) (25th, 50th, 75th percentiles of the SPL range, and comfortable voice level [CV]), RLAW values for the oldest group of females were found to be higher at each SPL percentile than those of the two younger age groups. The oldest group of males differed from the youngest group of males in RLAW values only at the 75th percentile level of SPL. Laryngeal airway resistance values were higher for females than males. As a group, the females generally had transglottal airflow that increased or remained relatively steady, whereas males maintained more linear changes in transglottal airflow and transglottal pressure as relative SPL increased. The present results suggest that separate norms need to be employed for males and females when determining RLAW values. Further, consideration should be given to examining the underlying airflow and pressure values when evaluating or monitoring changes in aerodynamic activity during voice production.

Technique for assessing nasal airway resistance in patients treated prosthetically.

This investigation was designed to compare nasal airway resistance (Rnaw) values by use of "head-out" plethysmography and standard posterior pressure-flow rhinometry. Fourteen adults who had prostheses because of velopharyngeal inadequacy caused by a variety of etiologic conditions were examined. Each patient performed rest breathing and sustained /m/ productions to develop Rnaw values for comparison. The results revealed increased Rnaw and decreased cross-sectional nasal airway area and derived velopharyngeal orifice area when the appliances were in place. The two techniques for assessing Rnaw produced comparable results when certain conditions were met. Clinical implications for team assessment of patients involved with prosthetic management are discussed.

Aerodynamic, acoustic, and perceptual changes following adenoidectomy.

Fourteen children were seen prior to adenoidectomy and at 1 month, 3 months, and 6 months following surgery. On each visit, nasal airway resistance values, nasal cross-sectional area estimates, nasalance scores, and perceptual ratings of nasality were collected. These data were analyzed to identify changes that were related to the time of the test, and to the primary indication for surgery (nasal airway obstruction or recurrent infection). Results revealed significant reduction in nasal airway resistance and significant changes in nasalance following surgery. Perceptual changes were not significant. Clinical implications of these findings are discussed.

Effects of the manual laryngeal musculoskeletal tension reduction technique as a treatment for functional voice disorders: perceptual and acoustic measures.

During a 2-year period, 17 patients with "functional dysphonia" were assessed and managed in a hospital setting. A single treatment approach, known as manual laryngeal musculoskeletal tension reduction, was employed. The effects of the therapy regimen were analyzed using perceptual and acoustical measures of vocal function. The results indicated a significant change in the direction of "normal" vocal function in the majority of patients within one treatment session. Perceptual measures of severity were consistently more likely to be rated as normal following treatment. Acoustic measures of voice confirmed significant improvements in jitter, shimmer, and signal-to-noise ratio (SNR). Results are discussed in terms of the clinical utility and effectiveness of this treatment approach for functional dysphonia.

Vocal characteristics of children with cleft lip/palate and associated velopharyngeal incompetence.

This investigation was designed to evaluate the relationship between aerodynamic measures of velopharyngeal competence and laryngeal function in individuals with repaired cleft palate. Twenty-seven cleft lip and palate or cleft palate individuals, between the ages of 4 and 16 years, were evaluated in an ENT clinic for assessment of vocal function. A commercially available aerodynamic (pressure/flow) system for evaluating velopharyngeal function was used to classify estimated opening of the velopharyngeal port during speech production. Aerodynamic measures of laryngeal function (transglottal pressure and airflow, and laryngeal airway resistance) were also collected. A computerized system for acoustic analyses of voice production was employed to determine vocal characteristics of pitch perturbation (jitter), amplitude perturbation (shimmer) and signal-to-noise ratio (SNR). The results suggested that the cleft speakers showed numerically larger measures of perturbation in the vocal signal, and greater laryngeal airway resistance than their normal controls. Subgroups of cleft palate speakers, based on their vocal dynamics, were proposed. Implications for medical and behavioral management for these subgroups are discussed.

Aerodynamic assessment of the speech of adults undergoing multichannel cochlear implantation.

This investigation was designed to evaluate the aerodynamic characteristics of the speech of adult multichannel cochlear implant (Nucleus, 21-channel) recipients. Five adults with an acquired profound sensorineural hearing loss were tested before implantation, immediately following implantation, and 3, 6, 9, and 12 months after implantation. A commercially available computerized pressure-flow instrumentation system was employed to assess the respiratory, laryngeal, velopharyngeal, and oral articulatory subsystems of speech of the implantees. The results of the investigation indicated 1) a slight increase in airflow rate values for sustained vowel /a/phonation after implantation, 2) a slight increase in duration of sustained vowel phonation from the preimplant period to the last postimplant period, 3) an increase in laryngeal airway resistance after implantation that resulted from a larger increase in estimated transglottal pressure than in transglottal airflow, 4) maintenance of normal velopharyngeal closure in oral-nasal contrastive contexts, and 5) slight increases in oral orifice area for fricative syllable utterances following implantation. Individual strategies for coordinated control of the speech mechanism appear to be potent variables to consider when assessing speech production.

Frequency and intensity effects upon temporal and aerodynamic aspects of vocal fold diadochokinesis.

The present study of vocal fold diadochokinesis in 18 young adult women yielded statistically significant differences in intensity (at percentiles 25%, 50%, 75% of range) of production for vowel /lambda/ repetition rate. In addition, there were statistically significant differences for vocal frequency and intensity effects for airflow rate through the vocal folds at the 25th, 50th, and 75th percentile points within the functional vocal range. Clinical applications of the data are suggested.

A study of nasometric values for normal nasal resonance.

It was the purpose of this study to obtain nasalance values for a large number of normal adult subjects speaking a variety of dialects of English. The Nasometer was used to measure the amount of nasal acoustic energy in the speech of 148 normal adults from four geographical regions of North America. Means and standard deviations for the nasalance and deviation scores are presented for each of three different reading passages. The Mid-Atlantic speakers were found to have significantly higher nasalance scores on all three reading passages. In addition, the female subjects had significantly higher nasalance scores on the Nasal Sentences. These differences are discussed with regard to potential reasons for their existence and implications for understanding velopharyngeal function in normal and abnormal speakers.

Changes in vocal resonance and nasalization following adenoidectomy in normal children: preliminary findings.

The purpose of this study was to evaluate changes that occur in certain aspects of vocal resonance and nasalization following adenoidectomy. Fourteen normal children were assessed prior to adenoidectomy and then at one month, three months, and six months following surgery. A unique combination of aerodynamic, acoustic, and perceptual measures were made. The aerodynamic component of the evaluation involved the use of posterior rhinomanometry to calculate nasal airway resistance (Rnaw) during relaxed nasal breathing. Acoustical measures consisted of "nasalance" scores (oral/nasal acoustic ratio) obtained during production of various speech stimuli. In addition, perceptual measures of change in vocal quality included listener judgments of severity and categorical ratings of nasality. Consistent patterns of change in vocal resonance and nasalization following adenoidectomy were identified. Clinical implications of these preliminary findings suggest that the maximum increase in nasality after tonsillectomy and adenoidectomy occurs at about one month, and referral to a speech-language pathologist should be considered if the hypernasality persists beyond three months.

Fetal alcohol syndrome: a description of oral motor, articulatory, short-term memory, grammatical, and semantic abilities.

Formal communication skills assessments were completed on eight children with diagnosed forms of fetal alcohol syndrome (FAS) ages four and one-half to nine and one-half years. Non-FAS children ages three and one-half to six and one-half years matched for ethnic background, living situation, and nonverbal cognitive ability served as controls. All but one of the FAS subjects demonstrated abnormalities of the speech mechanism within at least one major valve along the vocal tract. Mental age inconsistent articulation abilities were found in three FAS subjects when matched for nonverbal cognitive ability. The FAS children exhibited mental age inconsistent abilities in the comprehension and use of grammatical markers both in repetition and in spontaneous language tasks. Further, the FAS subjects also demonstrated reduced capacity to process and store critical elements when compared with non-FAS children. Clinical implications for the assessment of children with FAS are outlined.

Vocal function following vertical hemilaryngectomy: a preliminary investigation.

Seven consecutive male patients who received a vertical hemilaryngectomy were examined for vocal function employing video-stroboscopic, aerodynamic and acoustic measurement techniques. The results of this preliminary investigation suggest that with the group of patients studied, vocal quality was rated as "rough", "breathy" and "constricted". While large variability was noted between individuals, the general tendencies for the group included: (a) incomplete glottic closure; (b) supraglottic structures (ventricular folds, arytenoids) fulfilled or aided vibratory action of the remaining fold; (c) high average transglottal airflow; (d) reduced maximum phonation time; (e) high and more variable vocal frequency positioned near the top of the frequency range; (f) a lower, more variable, and restricted vocal intensity range, and (g) a reduced vocal fold diadochokinetic (vocal fold opening and closing action) rate. We are currently attempting to determine factors related to individual patient strategies for using either glottic or supraglottic valving during phonation.

A comparison of noninvasive procedures to assess nasal airway resistance.

Through sophisticated equipment has been used to determine nasal airway resistance (Rnaw), data must be interpreted cautiously because of the variability of procedures used to obtain the measures. The present investigation was designed to determine the effects of breathing versus a speech task, using a forward versus a resting tongue carriage, and the consistency of these measures on Rnaw values. Twenty young adult females performed a noninvasive procedure for assessment of Rnaw during rest breathing and nasal/m/ sound production with and without tongue anchoring over a 2-day period. No significant differences in Rnaw were found between days or tasks. Of the tasks examined, sustained/m/production and tongue anchoring procedures proved consistent adjuncts to quiet breathing for estimation of nasal airway resistance across days and airflow rate conditions. Clinical implications for the application of these procedures are discussed.