Effects of laryngeal endoscopy on the vocal performance of young adult females with normal voices

Arytenoid cartilage movements are hypokinetic in Parkinson's disease: A quantitative dynamic computerised tomographic study

BACKGROUND

Voice change is one of the earliest features of Parkinson's disease. However, quantitative studies of vocal fold dynamics which are needed to provide insight into disease biology, aid diagnosis, or track progression, are few.

METHODS

We therefore quantified arytenoid cartilage movements and glottic area during repeated phonation in 15 patients with Parkinson's disease (symptom duration < 6 years) and 19 controls, with 320-slice computerised tomography (CT). We related these measures to perceptual voice evaluations and spirometry. We hypothesised that Parkinson's disease patients have a smaller inter-arytenoid distance, a preserved or larger glottic area because vocal cord bowing has previously been reported, less variability in loudness, more voice dysdiadochokinesis and breathiness and a shortened phonation time because of arytenoid hypokinesis relative to glottic area.

RESULTS

Inter-arytenoid distance in Parkinson's disease patients was moderately smaller (Mdn = 0.106, IQR = 0.091-0.116) than in controls (Mdn = 0.132, IQR = 0.116-0.166) (W = 212, P = 0.015, r = -0.42), normalised for anatomical and other inter-subject variance, analysed with two-tailed Wilcoxon's rank sum test. This finding was confirmed in a linear mixed model analysis-Parkinson's disease significantly predicted a reduction in the dependent variable, inter-arytenoid distance (b = -0.87, SEb = 0.39, 95% CI [-1.66, -0.08], t(31) = -2.24, P = 0.032). There was no difference in glottic area. On perceptual voice evaluation, patients had more breathiness and dysdiadochokinesis, a shorter maximum phonation time, and less variability in loudness than controls. There was no difference in spirometry after adjustment for smoking history.

CONCLUSIONS

As predicted, vocal fold adduction movements are reduced in Parkinson's disease on repeated phonation but glottic area is maintained. Some perceptual characteristics of Parkinsonian speech reflect these changes. We are the first to use 320-slice CT to study laryngeal motion. Our findings indicate how Parkinson's disease affects intrinsic laryngeal muscle position and excursion.

Impact of topical anesthesia on acoustic characteristics of voice during laryngeal telescopic examination

OBJECTIVE:

The purposes of this study are to investigate the impact of topical anesthetic alone and with concurrent laryngeal telescopic examination on acoustic characteristics of vocal fold function. Comparison with phonation in controlled conditions may imply diagnostic information from the examination.

STUDY DESIGN:

Thirty males evaluated as having a normal voice were included in the study. The subjects were asked to phonate sustained /i/ with a naturally comfortable pitch and loudness in three consecutive experimental sequences as “control condition,” “anesthetic condition,” and “telescopic condition.” Acoustic analysis of fundamental frequency, jitter, shimmer, and harmonic to noise ratio in the three different conditions were executed.

RESULTS:

The mean and standard deviation of Fo in control condition, anesthetic condition, and telescopic condition were 130.1 ± 18.5 Hz, 125.7 ± 19.7 Hz, and 173.2 ± 35.1 Hz, respectively. The telescopic condition showed more negative change than that in control condition and anesthetic condition in other parameters. There was a significant difference ( P < 0.001) between control condition and telescopic condition in all four parameters.

CONCLUSIONS:

This study showed that anesthesia has little effect on voice performance for subjects with a normal voice. On the other hand, the acoustic characteristics changed significantly during telescopic performance. When doing interpretation of acoustic data, the abnormality of the acoustic characteristics might be the result of the procedures and not reflect vocal pathology. Laryngeal variations due to manipulation of telescope should be ruled out.

Acoustic characteristics of different target vowels during the laryngeal telescopy

OBJECTIVE

The aim of this study was to investigate the acoustic characteristics of target vowels phonated in normal voice persons while performing laryngeal telescopy. The acoustic characteristics are compared to show the extent of possible difference to speculate their impact on phonation function.

METHODS

Thirty-four male subjects aged 20-39 years with normal voice were included in this study. The target vowels were /i/ and /ɛ/. Recording of voice samples was done under natural phonation and during laryngeal telescopy. The acoustic analysis included the parameters of fundamental frequency, jitter, shimmer and noise-to-harmonic ratio.

RESULTS

The sound of a target vowel /ɛ/ was perceived identical in more than 90% of the subjects by the examiner and speech language pathologist during the telescopy. Both /i/ and /ɛ/ sounds showed significant difference when compared with the results under natural phonation. There was no significant difference between /i/ and /ɛ/ during the telescopy.

CONCLUSION

The present study showed that change in target vowels during laryngeal telescopy makes no significant difference in the acoustic characteristics. The results may lead to the speculation that the phonation mechanism was not affected significantly by different vowels during the telescopy. This study may suggest that in the principle of comfortable phonation, introduction of the target vowels /i/ and /ɛ/ is practical.

Acoustic Changes Related to Laryngeal Examination with a Rigid Telescope

The influence on voice quality of the insertion of endoscopic equipment with tongue anchoring and head position requirements during endoscopic evaluation has not been fully investigated. The present study attempted to examine the influence of: (1) the presence of a rigid endoscope and tongue anchoring, and (2) the angle of position technique (70-degree and 90-degree) on participants' vocal output during sustained production of the vowel /i/. Five acoustic measurements including fundamental frequency (F0) values, percent jitter values, relative average perturbation of F0 shimmer, and noise-to-harmonic ratios were used to represent participants' voice quality. Results indicated that F0 values were significantly influenced by the angle of sitting position, while percent jitter values, relative average perturbation of F0, shimmer, and noise- to-harmonic ratios were affected by the presence of a rigid endoscope and tongue anchoring.

Effects of topical anesthetic and flexible fiberoptic laryngoscopy on professional sopranos

This study examined the acoustic and perceptual effects of topical anesthetic and flexible fiberoptic laryngoscopy (FFL) against a control condition on the singing voices of ten professional sopranos. Recordings of a section of an aria, various scales, and a messa di voce exercise were obtained in the three experimental conditions. Acoustic analyses of the same aria section recorded during the three conditions were similar with respect to the distribution of energy across the spectrum (LTAS) and vibrato rate and extent. The ability of the participants to achieve their highest and lowest notes or to complete the messa di voce was also not affected by the anesthetic or FFL. Perceptual ratings of a variety of parameters by experienced singing teachers also revealed little difference across conditions with only "appropriate velopharyngeal closure" found to differ in one comparison. These results indicate that highly experienced operatic sopranos are either not affected by or appear to have the ability to compensate for the presence of anesthetic and the FFL. The most likely explanation is that this group of singers relied on a solid vocal technique. Results will need to be replicated on less accomplished singers before concluding that this medical procedure does not affect the operatic singing voice.

Análise de cantores de baile em estilo de canto popular e lírico:perceptivo-auditiva, acústica e da configuração laríngea

Objetivo: deste estudo foi verificar os ajustes laríngeos realizados por cantores profissionais do gênero popular durante a imitação do canto em estilo lírico uma vez que muitas vezes ao ouvirmos um cantor popular interpretar uma música clássica percebemos que o mesmo faz modificações em sua qualidade vocal, tentando se aproximar, por imitação, do canto lírico. Forma de estudo: Clínico prospectivo. Material e método: Foram analisados 26 cantores profissionais do gênero popular, 10 homens e 16 mulheres, atuantes em baile. Foi aplicado questionário sobre perfil vocal, realizada análise perceptivo-auditiva e acústica das vozes e avaliação nasofibrolaringoscópica para análise da configuração laríngea nos estilos de canto popular e lírico. Resultado: A análise perceptivo-auditiva revelou que, ao cantar um trecho de música em estilo lírico, o cantor popular muda a qualidade vocal, aumentando o vibrato, o volume vocal, melhorando a ressonância vocal e sobrearticulando mais as palavras. Na análise espectrográfica não foi observada a ocorrência do formante do cantor em nenhuma das vozes. O ajuste laríngeo realizado por cantores populares ao imitarem o estilo de canto lírico foi predominantemente o aumento das constrições ântero-posterior e mediana sendo que a constrição mediana ocorreu mais no sexo masculino. Os valores de jitter e shimmer reduziram significantemente na vogal cantada em relação à vogal falada nas vozes femininas.