[The Evaluation of Voice Quality via Signal Typing in Voice using Narrowband Spectrograms]. / Spektrografische Stimmtypenklassifizierung zur Beurteilung der Stimmqualität.

OBJECTIVE: Traditionally, voice quality is evaluated by auditory-perceptual judgment but objective-acoustic analyses are also valid tools. Spectrography is a part of objective-acoustic analyses and is used since around 50 years. Recently, Sprecher et al. (2010) designed a new classification scheme for signal typing in voice using narrowband spectrograms. The present study aimed to explore the external validation between these 2 methods in a larger dataset. MATERIALS AND METHODS: In total 300 voice samples were used based on the vowel [a:], in which n=270 had various degrees of dysphonia and n=30 were vocally normal. All voice samples were evaluated by 7 speech-language therapists using the RBH-scale and 2 judges analyzed the signal typing in voice using narrowband spectrograms. RESULTS: The intra- and inter-rater reliability of all RBH parameters was fair in average (kappa=0.234-0.383) but the rater reliability was moderate between the 2 judges rating signal typing in voice (kappa=0.457). A strong concurrent validity was identified between the signal typing in voice using narrowband spectrograms and auditory-perceptual judgment of hoarseness and breathiness (H: r=0.746, p=0.000; B: r=0.746, p=0.000) but only fair in roughness (r=0.370, p=0.000). CONCLUSION: The present results confirmed the results of Sprecher et al. (2010) and it might be meaningful to benefit signal typing in voice using narrowband spectrograms on sustained vowels as a valid complement in the evaluation of hoarseness and breathiness for clinical utility and research.

[Test-retest variability and internal consistency of the Acoustic Voice Quality Index]. / Test-Retest-Variabilität und interne Konsistenz des Acoustic Voice Quality Index.

BACKGROUND: The aim of this study was to determine the test-retest variability of the Acoustic Voice Quality Index (AVQI) and to investigate the weighting of the test's two components (sustained vowel and continuous speech) with regards to the final AVQI score. PATIENTS AND METHODS: During this study, 43 test subjects with varying degrees of hoarseness were each assessed twice using the AVQI. RESULTS: No statistically significant differences were found between the end results of the two AVQI repetitions (t = 1.205; p = 0.235). The test-retest procedure outcome value of 0.54 confirms a low level of AVQI score variability. The end result of the AVQI assessment is most strongly influenced by sustained phonation of the vowel /a/ (r(2) = 0.88.). Although sustained phonation has a significantly greater influence on AVQI score than continuous speech (z = - 3.34; p < 0.01), the latter component also makes a substantial contribution to the final result (r(2) = 0.55). CONCLUSIONS: The results confirm a low level of test-retest variability within the AVQI. Combining the two speech elements showed a greater contribution of sustained vowel phonation to the final AVQI score.

[Perceptual and acoustic evaluation of hoarseness]. / Auditive und apparative Heiserkeitsbewertung.

Voice disturbances require a multidimensional diagnostics. Hoarseness as a common symptom of dysphonia contains the parameters of breathiness and roughness. Perceptual voice assessment is designed to describe voice attributes and serve as a standardised means of communication among clinicians. In Germany a commonly used and researched perceptual scale is the RBH-scale, providing a measure of roughness (R), breathiness (B) and the overall grade (H) of dysphonia as judged by the listener on a scale of 0 to 3 (0: normal, 1: mild, 2: moderate, 3: severe). Acoustic analysis of the voice by means of the Goettingen hoarseness diagram is commonly used as well and enables to quantitatively describe the periodicity (roughness) and the noise content (breathiness) of voices, but not on a scale of 0 to 3. We suggest a possibility to present the result of the Goettingen hoarseness diagram on a scale analogously to the RBH-system to facilitate a better exchange of information about the severity of voice disturbances for colleagues or medical surveyors.

Clinical value of acoustic voice measures: a retrospective study.

Within this study a retrospective analysis of clinical voice perturbation measures, Dysphonia Severity Index and subjective perceived hoarseness was performed to determine their value under clinical aspects. The study included the data of 580 healthy and 1,700 pathologic voices, which were investigated under the following aspects. The relevant parameters were identified and their interrelation determined. Group differences between healthy and pathologic voices were figured out and investigated if voice quality measures allowed an automatic diagnosis of voice disorders. The analysis revealed significant changes between the clinical groups, which indicate the diagnostic relevance of voice quality measures. However, an individual diagnosis of the underlying voice disorder failed due to a vast spread of the parameter values within the respective groups. Classification accuracies of 75-90% were achieved. The high misclassification rate of up to 25% implied that in voice disorder diagnosis, the individual interpretation of the parameter values has to be done carefully.

[On the auditory evaluation of voice quality]. / Zur auditiven Bewertung der Stimmqualität.

BACKGROUND: For routine clinical purposes, dysphonic voices are assessed perceptually using the GRBAS scale or analogues. For clinical application, the crucial question is the interrater reliability (IRR) of the auditory perceptual assessment of voice quality. Therefore, the IRR of the four point RBH (roughness, breathiness, hoarseness vs overall grade) scale was studied. Other parameters, e.g. validity and intrarater reliability were not considered. METHODS: A total of 78 patients read a standard text "Der Nordwind und die Sonne". These samples were evaluated by 19 speech and voice therapy students according to the degree of roughness, breathiness and hoarseness. Data were subjected to reliability analysis. RESULTS: Our data indicate a high IRR with a Cronbach's alpha of 0.94. No single rating of the 19 raters could be omitted without decreasing the IRR. DISCUSSION: The data indicate that the perceptual assessment of hoarseness for running speech is highly reliable. The application of the RBH scale is suitable for clinical purposes. It should be considered as an outcome measure.

[Objective description of voice quality using the hoarseness diagram]. / Objektive Beschreibung der Stimmgüte unter Verwendung des Heiserkeits-Diagramms.

The need for an objective assessment of voice quality can be seen in the increasing use of acoustic analysis methods for clinical diagnosis and research. The hoarseness diagram allows clinicians to objectively describe even highly disturbed or aphonic votes. Its application possibilities are illustrated in three case studies in which changes in voice quality were monitored during voice rehabilitation. The distributions of voice groups that were defined on the basis of specific pathophysiological phonation conditions were then compared for their acoustic differences. The groups comprised various phonation conditions after the resection of laryngeal tumors and different types of laryngeal paralyses. Interpretation of the results suggests a direct correspondence of the hoarseness diagram coordinates and the irregularity of vibration on the one side and the degree of glottal closure on the other. This illustrates the potential usefulness of the hoarseness diagram in a clinical context.

[Cepstrum analysis in voice disorders]. / Cepstrumanalyse bei Stimmerkrankungen.

Objective data and reproducible procedures are increasingly demanded for assessment and long-term comparison in voice disturbances. Well-known electroacoustic methods like formant analysis, autocorrelation and inverse filtering have been applied for this purpose, though without leaving experimental stage. The cepstrum analysis presented here permits an easy and distinct separation of glottal pitch and filter function of the vocal tract. In this study, 112 normal and hoarse voices were analyzed. The sum of amplitudes of the first cepstral pitch peaks differed significantly between the different degrees of hoarseness (0-3). Disturbances producing hoarseness, however, could not be sufficiently differentiated by the method in its present state.

[Chronic hoarseness in children. Evaluation based on personal series of 64 cases]. / La dysphonie chronique de l'enfant. Mise au point à la lumière d'une série personnelle de 64 cas.

Chronic hoarseness is frequent among children, as shown by 64 cases observed over an 18-month period in a specialized phoniatric outpatients clinic. Age at the first consultation for these 64 patients was 3-14 year although the hoarseness was already known for more than 1 year in 40 patients (62.5%). The main findings at laryngoscopy were an edematous vocal cord (33%), a unilateral or bilateral nodular lesion (26%), and an epidermoïd cyst (17%). The larynx was normal in 2 patients only. Orthophonic re-education was prescribed for 45 patients (70%); it was followed by laryngeal microsurgery in 3 patients: 9 patients were completely cured, 26 were improved, 4 showed no improvement, 16 could not be located for follow-up. Chronic hoarseness in children has numerous etiologies which can be divided into 5 main groups. The 2 more frequent are the hyperkinetic or hypokinetic laryngeal dysfunctions and the congenital lesions. The 3 other groups are much less frequent: juvenile laryngeal papillomatosis, recurrent palsy and pithiatic aphonia. Laryngoscopy is important for the diagnosis. Orthophonic re-education represents the main treatment; it completes the surgical treatment when microsurgery of the larynx is necessary.