M. De Bodt

Validation of the Voice Handicap Index by Assessing Equivalence of European Translations

Objective: We aimed to assess the equivalence of translations of the Voice Handicap Index (VHI). Patients and Methods: Confirmatory factor analysis was used to assess equivalence of the US version and several translations including (1) Dutch, (2) Flemish Dutch (Belgium), (3) UK English, (4) French, (5) German, (6) Italian, (7) Portuguese and (8) Swedish. VHI questionnaires were gathered from 1,281 subjects. Patients were classified into 11 voice lesion categories. Patients with incomplete response (4%) and patients within voice lesion categories with small numbers were excluded from further analyses, leaving a cohort of 1,052 patients from 8 countries. Results: The internal consistency of the VHI proved to be good. Confirmatory factor analysis across countries revealed that a 3-factor fixed measurement model best fitted the data; the 3 subscales appeared to highly intercorrelated, especially in the US data. The underlying structure of the VHI was also equivalent regarding various voice lesions, but distinct groups were recognized with respect to the height of the VHI scores, indicating that various voice lesions lead to a diversity of voice problems in daily life. Conclusion: The US VHI and the translations appeared to be equivalent, which means that the results from studies from the various included countries can be compared.

Poor voice quality in future elite vocal performers and professional voice users.

The voice quality of 86 occupational voice users, i.e., students of a high school for audiovisual communication, was assessed by means of a multidimensional test battery containing: the GRBAS scale, videolaryngostroboscopy, maximum phonation time, jitter, lowest intensity, highest frequency, dysphonia severity index (DSI), and voice handicap index (VHI). In a questionnaire on daily habits the prevalence of smoking, eating habits, and vocal abuse were recorded. A comparison of the voice characteristics of the future occupational voice users with a control group revealed significant differences. The results of the VHI and the DSI of these students revealed significantly worse scores than the score of a control group characterized by no vocal complaints. Moreover, the questionnaire on daily habits showed that the future elite vocal performers and professional voice users take less precautions for the care of their voices. These findings support the importance of a good balanced vocal coaching.

Effect of Cleft Type on Overall Speech Intelligibility and Resonance

The main purpose of this study was to measure and compare the effect of an unilateral cleft lip and palate (UCLP) and a bilateral cleft lip and palate (BCLP) on overall speech intelligibility, nasalance and nasality. An additional objective was to compare the nasalance and nasality patterns of cleft palate children with the available normative data for normal children. The subjects were 37 children with an UCLP (19/37) or a BCLP (18/37) with normal cognitive and motor functions and normal hearing levels. All subjects had a non-syndromic cleft, followed the same surgical protocol and did not undergo secondary pharyngeal surgery. To measure and compare the effect of cleft type, objective and subjective assessment techniques were used. For the objective assessment of nasal resonance the nasometer and the mirror-fogging test were used. Nasalance scores were obtained, while patients produced sounds, read three standard passages or repeated sentences focusing on specific consonants. A perceptual evaluation of speech, the Gutzmann (1913) test and the tests of Bzoch (1989) were used as subjective assessment techniques. The perceptual assessment of the overall speech intelligibility was based on the spontaneous speech and reading or repeating of the nasometric sentences. These samples were judged by three speech pathologists using a 4-category nominal scale. A subjective test (Morley, 1945) was used to evaluate the velopharyngeal mechanism. The findings of the present study show no statistically significant differences for nasalance values, nasality and overall speech intelligibility between the UCLP and BCLP children. Significant differences were found between the data of the normal group and the cleft palate children. These differences included nasalance values as well as nasality data and overall speech intelligibility.

Item Reduction of the Voice Handicap Index Based on the Original Version and on European Translations

Objective: Constructing an internationally applicable short-scale of the Voice Handicap Index (VHI). Methods: Subjects were 1,052 patients with 5 different types of voice disorder groups from Belgium, France, Sweden, Germany, Italy, The Netherlands, Portugal, and the USA. Different 9- and 12-item subsets were selected from the 30 VHI items using (1) the first factor of an unrotated factor analysis (narrow range subsets) and (2) the first three factors after promax rotation (broad range subsets). Country-specific subsets were selected to test deviations from the international subsets. For all subsets, reliability was investigated using Cronbach’s alphas and correlations with the total VHI. Validity was investigated using regression on voice disorder groups. All analyses were performed for the total and for all country-specific subject samples. Results: Reliability was high for all item subsets. It was lower for the international compared to the country-specific subsets and for the broad range compared to the narrow range subsets. Validity was best for the broad range subsets. Validity was better for the international than for the country-specific subsets. For all statistics the 12-item subsets were not essentially better than the 9-item subsets. Conclusion: The international broad range 9-item subset forms a scale which approximates well the total VHI.

Normative voice range profiles of male and female professional voice users.

Normative voice range profiles (VRP) are calculated for a group of male and female teachers, based on 43 and 46 recordings, respectively. All individuals had healthy voices. These normative VRPs contain 95% prediction intervals for both frequency and intensity. They are based on a series of mathematical transformations of the original individual VRPs in order to maintain in the normative VRPs the typical oval VRP shape, including the dip between modal and falsetto register. The normative VRPs presented are directly applicable in the clinical practice of otolaryngologists and speech-language pathologists.

Good speech recognition and quality-of-life scores after cochlear implantation in patients with DFNA9.

Objective: To compare audiometric and quality-of-life results in DFNA9 patients who received a cochlear implant with cochlear implant patients with adult-onset progressive sensorineural hearing loss. Study Design: Prospective comparative design; results were collected cross-sectionally. Setting: Tertiary referral center. Patients: Eleven DFNA9 patients were included in the study as well as a comparative group of 39 postlingually deafened cochlear implant subjects with adult-onset progressive sensorineural hearing loss. Interventions: All patients received a cochlear implant. Subjects were implanted with either the Nucleus 24M/RCS or Med-el Combi 40+ cochlear implant systems implementing the SPEAK, ACE, or CIS+ coding strategies. Mean Outcome Measures: Speech recognition was determined by means of phonetically balanced monosyllabic word lists. The Hearing Handicap Inventory for Adults, the Glasgow Benefit Inventory, and the Scale for the Prediction of Hearing Disability in Sensorineural Hearing Loss were used to quantify the quality of life. Results: The results show that the speech perception and the quality of life of the DFNA9 patients do not differ significantly from the control group (p = 0.179; p = 0.56). Conclusion: In spite of the fact that DFNA9 is a disease that is known to involve cochlear dendrites, cochlear implantation is a good option for treatment of deafness in DFNA9.

Relevance of subglottic pressure in normal and dysphonic subjects.

The purpose of this study was to determine the clinical value of subglottic pressure (SGP) in normal and dysphonic subjects. “The airway interrupted method” was used to measure the intra-oral pressure. Voice samples from 60 healthy subjects and 79 dysphonic patients were recorded under normal conditions of pitch and intensity. In normal subjects, age and gender have no significant impact on mean and peak SGP. The peak SGP measurements are significantly higher in dysphonic patients and could be included in the basic clinical set of objective voice parameters. No differences could be shown between pre- and postoperative assessments or between groups of dysphonic patients.

Comparison of sound processing strategies for osseointegrated bone conduction implants in mixed hearing loss: multiple-channel nonlinear versus single-channel linear processing.

Objectives Evaluation of a single-channel linear bone conduction implant sound processor (S-BCI) and a multiple-channel nonlinear bone conduction implant sound processor (M-BCI) with objective and subjective measures in patients with mixed hearing loss. Study Design In total, 20 patients with mixed hearing loss were included in the study. For either sound processor aided thresholds and speech perception in quiet with monosyllables were measured. Speech perception in noise was measured with sentences. Two different configurations were used: speech and noise at 0° (S0N0) and speech at 0° and noise at 180° (S0N180). The M-BCI was tested in both omnidirectional and directional mode. Patients were first fitted with the S-BCI and evaluated 3 weeks later. The M-BCI was fitted and, again 3 weeks later, evaluated. Subjectively, patients compared both sound processors with the APHAB questionnaire. Results Aided thresholds were similar for both sound processors in the low- and mid-frequency range. For speech in quiet, no significant differences between both sound processors were observed. For speech in noise in the S0N0 condition, the M-BCI-thresholds were 1.7 dB (SD, 2.2dB; p = 0.002) more favorable than with S-BCI. For the S0N180 configuration, an improvement of 5.8 dB (SD, 2.8dB; p < 0.001) was seen for the directional mode relative to S-BCI. The APHAB showed statistically significant subjective improvement with the M-BCI on all subscales relative to S-BCI. Conclusion Speech intelligibility in noise is better with M-BCI than with S-BCI. This was attributed to better high-frequency gain provided by the M-BCI. Improved signal processing strategies may have contributed to subjective preference for the M-BCI.

Voice Recognition from Spectrograms: A Wavelet Based Approach

The performance of a pattern recognition technique is usually determined by the ability of extracting useful features from the available data so as to effectively characterize and discriminate between patterns. We describe a novel method for feature extraction from speech signals. For this purpose, we generate spectrograms, which are time-frequency representations of the original signal. We show that, by considering this spectrogram as a textured image, a wavelet transform can be applied to generate useful features for recognizing the speech signal. This method is used for the classification of voice dysphonia. Its performance is compared with another technique taken from the literature. A recognition accuracy of 98% is achieved for the classification between normal an dysphonic voices.

Life-Threatening Macroglossia after Posterior Fossa Surgery: A Surgical Positioning Problem

A 55-year-old woman was operated in the lateral park bench position with significant neck flexion and oral packing. Macroglossia was noticed immediately postoperatively after endotracheal extubation. The patient was reintubated for 13 days and subsequently required a tracheostoma. After the placement of the tracheostoma and the removal of the endotracheal tube, the congestion of the tongue decreased markedly within 24 hours. Macroglossia is a rare complication following posterior fossa procedures with few cases reported so far. It can cause airway obstruction, which could be a life-threatening complication, and it therefore requires prompt treatment. The aetiology of postoperative macroglossia remains uncertain and has been attributed to arterial, venous and lymphatic compression, mechanical compression, or neurogenic causes. This article describes new insights into aetiology and also describes preventive measures and possible treatment.