Baha implant as a hearing solution for single-sided deafness after retrosigmoid approach for the vestibular schwannoma: audiological results.

Skull base tumors and, in particular, vestibular schwannoma (VS) are among the etiological reasons for single-sided deafness (SSD). Patients with SSD have problems in understanding speech in a noisy environment and cannot localize the direction of sounds. For the majority, this is the handicap for which they try to find a solution. Apart from CROS hearing aids, Baha is one of the most frequently used systems for SSD compensation. 38 patients with single-sided deafness after retrosigmoid removal of a vestibular schwannoma underwent testing with a Baha softband from September 2010 to August 2014. Sixteen patients (42 %) finally decided to accept Baha implantation. Subjective experience with the Baha softband was evaluated by patients using the BBSS questionnaire immediately after testing. Objective evaluation of the effect was performed as a measurement of the sentence discrimination score in noise and side horizontal discrimination without a Baha and 6 weeks and 12 months after a sound processor fitting. There was a significant improvement in sentence discrimination in the 6 week (64.0 %) and 1 year (74.6 %) interval of follow-up in comparison with understanding without Baha (24.0 %, p = 0.001) in situations when sentences are coming from the side of the non-hearing ear and noise contralaterally with SNR -5 dB. Baha can significantly improve sentence discrimination in complex-listening situation in patients with SSD after the VS surgery.

Baha implant as a hearing solution for single-sided deafness after retrosigmoid approach for the vestibular schwannoma: surgical results.

Skull base tumors and, in particular, vestibular schwannoma (VS) are among the etiological reasons for single-sided deafness (SSD). Patients with SSD have problems in understanding speech in a noisy environment and cannot localize the direction of sounds. Baha is one of the most frequently used systems for SSD compensation. Out of 38 patients with SSD after retrosigmoid removal of VS who underwent testing with Baha softband, 16 were satisfied and were indicated for Baha implantation. Two surgical approaches have been used-the Nijmegen linear incision technique with subdermal thinning (Group I, implant BI300) and fast surgery technique without subdermal thinning (Group II, implant BIA400). The duration of the surgery, the implant stability measured by Ostell, and skin or soft tissue reactions in long range follow-up were evaluated and compared between Group I and II. There was a difference in duration of surgery, in Group II procedures averaged significantly faster (p > 0.001). In both groups, there was a similar trend of the gradual increase of implant stability. In the Group I and II, there was comparable rate of the skin or soft tissue reactions grade 0, I, II, or III. We have proved Baha to be a suitable possibility for SSD patients after the removal of VS, regardless of the approach. After the retrosigmoid approach to the VS, the key step of Baha implantation must be to reach intact healthy bone to avoid implantation into scar tissue.

[Speech intelligibility in noise at presbycusis]. / Rozumení reci v sumu u presbyakuze.

Evaluation of speech recognition is possible by presenting testing material in sentence form with presence of competitive noise. We developed new test of sentence intelligibility in noise in the Czech language. This article demonstrates results of the influence of the babble noise on sentence intelligibility in hearing impaired listeners with presbycusis. The time characteristics of babble noise are similar to human voice. That is the reason why this noise masking is more enhanced at the central hearing level than any other noise masking. A group of 423 persons was divided into younger group (age from 40 to 65 years, N = 191, mean age 55.8 years.) and older group (age from 66 to 85 years, N = 232, mean age 75.4 years). For these two age groups, we compared the test performance in the subgroups stratified by the speech audiometry in silence. We demonstrate a statistically significant worse understanding of sentences in the older group against the younger group listening to sentences at level 65 dB SPL in competitive noise at level 65 dB SPL (p = 0.05). The development of the sentence intelligibility in noise test increased the possibilities of audiological examination by another test, which was up to now missing in the Czech language.

[30 years of the cochlear implantations in the Czech Republic]. / 30 let kochleárních implantací v Ceské republice.

Cochlear implant is the unique sensory neuroprosthesis and still the only one used in clinical praxis. The function of the inner ear is replaced with direct electrical stimulation of the cochlear nerve. It is 30 years since the first cochlear implantation has been performed with the Czech single-channel cochlear neuroprosthesis. There are more than one thousand users of cochlear implants in the Czech Republic nowadays. Cochlear implants have become a standard of care of patients with severe hearing loss. It allows user inclusion to the society with only a minimum of obstacles.Key words: cochlear implant, history, neuroprosthesis, severe hearing loss.

Influence of age on speech intelligibility in babble noise.

Problems with hearing aids, particularly with regard to speech intelligibility in the presence of noise, are commonly reported by older individuals in everyday practice. The main goal of this study was to measure differences in speech intelligibility between older and younger people and to establish how speech intelligibility in competitive noise differs between younger and older populations with similar hearing status. More than 400 persons were tested using the Czech Test of Sentence Intelligibility in Babble Noise and divided into younger (40-65 years) and older (66-85 years) age groups. Test performance was compared between age groups based on subgroups stratified by SRT values (speech reception threshold in word audiometry in silence). Results showed a significant correlation between older age and diminished sentence intelligibility in competitive noise. Evaluation using a nonparametric U­test showed a statistical difference between the younger and older groups in sentence intelligibility, with a speech signal presented at 65 dB sound pressure level (SPL) and competitive babble noise also presented at 65 dB SPL. Increased difficulty in the use of hearing aids in older users is related, among other things, to a reduced ability to discriminate speech not only in silence but particularly in competitive variable noise due both to their aging auditory functions and to a diminished capacity to differentiate the time factors of sounds. It is probably connected with the diminished function of inhibitory neurons.

Central auditory processing disorder (CAPD) in children with specific language impairment (SLI). Central auditory tests.

The aim of this project is to use central auditory tests for diagnosis of central auditory processing disorder (CAPD) in children with specific language impairment (SLI), in order to confirm relationship between speech-language impairment and central auditory processing. We attempted to establish special dichotic binaural tests in Czech language modified for younger children. Tests are based on behavioral audiometry using dichotic listening (different auditory stimuli that presented to each ear simultaneously). The experimental tasks consisted of three auditory measures (test 1-3)-dichotic listening of two-syllable words presented like binaural interaction tests. Children with SLI are unable to create simple sentences from two words that are heard separately but simultaneously. Results in our group of 90 pre-school children (6-7 years old) confirmed integration deficit and problems with quality of short-term memory. Average rate of success of children with specific language impairment was 56% in test 1, 64% in test 2 and 63% in test 3. Results of control group: 92% in test 1, 93% in test 2 and 92% in test 3 (p<0.001). Our results indicate the relationship between disorders of speech-language perception and central auditory processing disorders.

Computational modelling of effect of tonsillectomy on voice production.

The aim of this study is to develop mathematical 3D finite element (FE) models for numerical simulations of vibroacoustic properties of the human vocal tract after a tonsillectomy. Similar experimental studies are not easily realizable on living subjects. The FE models of the acoustic spaces corresponding to the human vocal tract for the Czech vowels /a:/ and /i:/ and the acoustic space around the human head were used in numerical simulations of phonation. The acoustic resonant characteristics of the FE models were studied using modal and transient analyses (excitation by a short pulse). Calculated results show that a tonsillectomy causes a frequency shift of the 3rd (down by approximately 180 Hz) and 4th (down by approximately 120 Hz) formants down to the lower frequencies for the vowel /a:/ and similarly for the 2nd, 4th and 5th formants for the vowel /i:/ (all down by approximately 100 Hz). Similar effects and results can be found in experimental studies in literature. The formant changes are dependent on the size of additional acoustic spaces that occur after a tonsillectomy. The verification of the model was performed on the recordings of patients before and after the tonsillectomy operation. Multi-Dimensional Voice Program (MDVP Advanced, KAY Elemetrics Corp.) was used for the comparing of the formant centre frequencies. Very small differences in the results of subjective evaluation of the voice before and after tonsillectomy were found.

Acoustic parameters for classification of breathiness in continuous speech according to the GRBAS scale.

OBJECTIVES: The purpose of this study was to classify objectively breathiness in continuous speech according to a subjective evaluation of voice based on the GRBAS scale. STUDY DESIGN: A retrospective, experimental study. METHODS: A total of 593 records with read text were twice evaluated by five experts according to the GRBAS scale within two sessions with a time delay of at least 2 weeks. The records were subsequently subjected to acoustic analysis using parameters which do not rely on the accurate estimation of fundamental frequency: Glottal-to-Noise Excitation ratio, Cepstral Peak Prominence Pearson r at autocorrelation peak, Breathiness Index, and the ratio of high- to mid/low-frequency energy. These parameters were subsequently analyzed and a total of 92 features were created for each record. After feature space reduction based on Correlation Feature Selection and Information Gain, the feature space was reduced to four parameters. These four parameters were used for classification of breathiness. RESULTS: In the final set of four, the acoustic parameters have significantly different mean ranks in every grade of breathiness according to the GRBAS scale (Kruskal-Wallis test [P < 0.001]). The accuracy of classifier for objective evaluation of level of breathiness based on the discrete scale of breathiness reached 77%. Assuming continuous grades of breathiness, the classifier reached ρ = 0.92 (P < 0.001). CONCLUSIONS: The level of breathiness in continuous speech can be effectively described by automatic system-based analysis of acoustic measures. The proposed automatic system is able to determine the level of breathiness in continuous speech with sufficient precision.

Effectiveness of transoral laser microsurgery for precancerous lesions and early glottic cancer guided by analysis of voice quality.

BACKGROUND: The purpose of this study was to show our comparison of the quality of voice obtained after superficial transoral endoscopic cordectomies (types I, II, and III) according to the European Laryngological Society classification versus the more extended cordectomy (types IV and V) among patients with glottic precancerous lesions or early glottic cancer. METHODS: Sixty-two patients underwent vocal assessment after cordectomy (types I-V) for dysplasia, Tis, T1a, T1b, and T2 lesions. RESULTS: Cordectomy (types I-III) had good vocal outcomes. Cordectomy (types IV-V) showed less favorable outcomes, p < .005 in common parameters of voice range profile and symmetry in stroboscopy after cordectomy (types IV-V), with significant voice handicap index. Recurrences were found in 4 patients with T1b and T2 cancer. Two cases were managed by a higher type of cordectomy, and the other 2 by total laryngectomy. CONCLUSION: Effect of transoral laser microsurgery on quality of voice depends on the type of cordectomy and the site of the lesion.