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PubMed2001

[Phoniatric aspects in microsurgical removal of benign vocal cord changes].

INTRODUCTION: Microsurgery of benign vocal cord lesions is usually done to improve, to restore or to preserve patients' voice. Solid anatomical and physiological knowledge concerning the voice are basic requirements of any surgeon operating in this field. PREOPERATIVE DIAGNOSTICS AND DOCUMENTATION: The significance of patients' history as well as phoniatric investigation, laryngoscopic and stroboscopic findings and their proper documentation are presented. INDICATIONS: The surgical procedure must be part of an extensive therapeutical concept that also takes into consideration drug therapy as well as voice therapy procedures to improve voice quality. POSTOPERATIVE REGIMEN: The care for the patient's voice usually goes beyond surgery. To gain the best possible postoperative results, several steps are necessary in addition to surgical procedures. These steps will be pointed out.

Humans↗
PubMed2002

[Acoustic analysis of nocturnal bronchial obstruction].

Patients with obstructive pulmonary disease also have respiratory problems in sleep. The continuous acoustic lung sound detection together with a cardiorespiratory polysomnography allows a synchronous registration of bronchial obstruction as well as vigilance and respiratory parameters in sleep.A total of 20 patients (9 male and 11 female) with known obstructive airway disease and evident diurnal bronchial obstruction were investigated. We did a monitoring in all patients with a nocturnal continuous acoustic lung sound detection together with a cardiorespiratory polysomnography. The mean age was 55 +/- 12 years (range 23 to 74). In all patients acoustic nocturnal bronchial obstructions could be registered. The wheezing-time (time portion of wheezing while sleeping) was 32.1 +/- 27.4 % (mean +/- SD). We could not proof reliable a rhythm of bronchial obstructions. Only 3 patients had increased bronchial obstructions between 3 and 5 AM. The sleep structure was disturbed in 16 of 20 patients with reduced deep sleep, REM sleep and prolonged sleep latency. Knowing about nocturnal bronchial obstructions helps to adapt the antiobstructive therapy. One can expect that an improvement of the respiratory situation also improves sleep quality.

Adult↗
PubMed2002

[Continuous acoustic monitoring of nocturnal bronchial obstructions].

Patients with bronchial asthma often have respiratory problems in sleep. The effects of bronchial obstructions while sleeping have been analysed in some studies. For an exact assessment the sleep itself must not be disturbed by the method. The continuous acoustic lung sound detection is such a method. It helps to assess the circadian rhythm during antiobstructive therapy which may lead to a better sleep quality and daytime fitness.

Airway Resistance↗
PubMed2003

[Acoustic follow-up of nocturnal bronchial obstruction therapy].

Long acting beta 2-agonists belong to the basic therapy of COPD. Especially patients with nocturnal respiratory problems may benefit from this therapy. Long term recording of lung sounds is a new method for quantitative measurements of bronchial obstructions. In combination with polysomnography an evaluation of cardiorespiratory parameters and sleep structure is possible. A total of 10 patients (8 male and 2 female) with moderate COPD (FEV1 58 +/- 11 %) and signs of bronchial obstruction were investigated. The combination of acoustic long term recording and polysomnography was done for 2 or 3 nights without and under therapy (long acting beta 2-agonist, 50 microg Salmeterol). In all patients we could find nocturnal bronchial obstruction events. Nocturnal wheezing time was reduced during therapy to 33 +/- 17 % (1. therapy night, n. s.) compared to 49 +/- 30 % without therapy (control night) and to 17 +/- 17 % (2. therapy night, n = 6, p < 0.05) vs. 51 +/- 30 % (control night, n = 6). Sleep efficiency and REM sleep increased (n. s.) under therapy, deep sleep stages NREM III/IV were nearly the same. Acoustic long term monitoring confirms the reduction of nocturnal bronchial obstructions under therapy with beta 2-agonists. A better sleep quality may be expected from the improvement of the respiratory situation during sleep.

Adrenergic beta-Agonists↗
PubMed2003

[Sound localization cues of binaural hearing].

The ability to localize sound sources in space is of considerable importance to the human safety- and survival-system. Consequently the current scientific interest in improving the safety-standard i. e. in air-traffic control has provided a new momentum for investigating spatial hearing. This review deals with the nature and the relative salience of the localization cues. Localization refers to judgements of the direction and distance of a sound source but here we will deal with direction only. We begin with a short introduction into the so-called Duplex theory which dates back to John William Strutt (later Lord Rayleigh). The idea is that sound localization is based on interaural time differences (ITD) at low frequencies and interaural level differences (ILD) at high frequencies. If the head remains stationary neither a given ITD nor an ILD can sufficiently define the position of a sound source in space. On such a theoretical basis cones of confusion which open outward from each ear can be predicted ambiguously projecting any source on the surface of such a cone onto an interaural axis. Our restricted ability at localizing sound sources in the vertical median plane is another example of possible ambiguity. At the end of the 19th century scientists already realized that occlusion of the pinnae cavities decreases localization competence. As a result of later achievements in physics and signal-theory it became more obvious that the pinnae may provide an additional cue for spatial hearing and that the outer ear together with the head and the upper torso form a sophisticated direction-dependent filter. The action of such a filter is mathematically described by the so-called Anatomical Transfer Function (ATF). The spectral patterning of the sound produced by the pinnae and the head is most effective when the source has spectral energy over a wide range and contains frequencies above 6 kHz, that is it contains wavelengths short enough to interact with the anatomical characteristics of the outer ears. Scientific findings further suggest that spectral patterns like peaks and notches may also be exploited monaurally, albeit an a priori-knowledge at the central-auditive level concerning the corresponding transfer functions and relevant real-world sounds is required. Binaural spectral cues are more likely to play a major role in localization. They are derived from another transfer function, the so-called Interaural Transfer Function (ITF), being the ratio of the ATFs at the two ears. The contributions of all these cues may sometimes not be enough to prevent the listener from opting for the wrong direction. But things can be eased by allowing head-movements: More than 60 years ago science reasoned that small head movements could provide the information necessary to resolve most of the ambiguities. Recent studies have proved that these findings have been accurate all along.

Cues↗
PubMed2003

[Oropharyngeal vocal tract space during singing--comparison of tactile-kinesthetic and auditory perception with objective endoscopic findings].

BACKGROUND: In this study we compared the perceived diameter of the vocal tract's oropharyngeal part with the diameter that was determined endoscopically. METHODS: 28 singers (13 male, 15 female) were examined with transnasal fiberscopic pharyngoscopy while singing the vowels /a/, /i/ and /u/ in 4 different timbres (normal, opened, covered, dumpled) and 3 different pitches (chest/modal register, subjective comfortable pitch for singing, head/falsetto register). The tactile-kinesthetic and auditive rating of the singers, the auditive rating of a singing teacher and the visual-endoscopic analysis of three laryngologists were compared. RESULTS: The tactile-kinesthetic and auditory self-perception of the singers was quite different from the auditive perception of a singing teacher and visual endoscopic findings of the laryngologists. The singers had the impression that the different singing timbres (normal, opened, covered, dumpled) influence oropharyngeal vocal tract space during singing. They judged the vowel itself and the pitch as having very little influence. Based on his auditory perception, the singing teacher also rated that the timbre plays an important role for the oropharyngeal vocal tract space but he found vowels to be the parameter with the greatest impact. Via visual endoscopic examination we found that, among the three parameters (vowel, timbre, pitch), the different vowels are most influential on the oropharyngeal vocal tract space. Analysis of video sequences revealed that pitch and timbre are less important. CONCLUSION: Subjective tactile-kinesthetic and auditory perception of the singers differs from auditory perception of the singing teacher as well as from endoscopic findings. The endoscopically determined oropharyngeal vocal tract space during singing the vowels /i/ or /u/ tends to be larger compared to the oropharyngeal vocal tract space while singing the vowel /a/.

Adult↗
PubMed2004

[Examination to possibilities of a physiological fitting of cochlear implants].

BACKGROUND: Cochlear implants (CI) convert acoustic events into electrical pulses. The auditory nerve picks these tiny electrical pulses up and sends them to the brain. The dynamics of the audible sound is compressed considerably. The limits for stimulation are determined with the patient. A map law determines which sound pressure level is assigned to which stimulation level. A sufficient speech understanding requests an allocation of high stimulation levels for weak sound signals. The higher the sound level, the lower the increase. Unfortunately, with such kind of map law unwanted background noise is also presented as well audible stimulation. These stimuli are often annoying to CI users in everyday situations. PATIENTS AND METHOD: The possibility to give an s-shaped course to these map laws was examined in 9 patients. After the fitting procedure their speech understanding were tested. The results were compared with the results of former tests. RESULTS: 8 patients reported definite improvement of their hearing situation. Such map laws seem, therefore, suitable to optimise speech processor programming.

Adult↗
PubMed2005

[Measurement of noise protection in functional magnetic resonance imaging].

BACKGROUND: Functional magnetic resonance imaging (fMRI) can detect changes in oxygen saturation of the brain. Fast changing high gradient fields are necessary which produce high levels of noise. In studies of the auditory cortex, auditory stimuli have to be perceived and discriminated against the noise level of the activated tomograph. MATERIAL AND METHODS: The generated frequency bands and their intensities during fMRI with a Siemens Magnetom Vision, 1.5 T, EPI sequence were measured in the outer ear canal of a dummy head. Noise attenuation was evaluated with four different noise muffs (simple/inexpensive products, quality product, specialized fMRI muffs). RESULTS: Without protection, peak noise levels reached up to 111 dB(A) near 1000 Hz in the dummy ear canal. Major noise attenuation was only found at higher frequencies (4000 Hz by about 25 dB; 8000 Hz by about 35 dB) with the quality product and the specialized fMRI muffs. CONCLUSION: Only quality noise products can sufficiently protect patients from high sound pressure levels of tomograph noise. If in the future higher gradient fields are applied at faster slew rates, acoustic stimuli can safely be applied only in combination with increased hearing protection systems in order to minimize the risk of noise trauma.

Ear Protective Devices↗
PubMed2004

[Electrophysiologic examinations in low frequency hearing impairment: clinical and prognostic aspects].

INTRODUCTION: Low-frequency hearing impairment (LFHI) is mainly associated to endolymphatic hydrops and shows a high variety of possible outcomes. Electrophysiologic examinations are widely recommended in diagnostics of LFHI, wheras up to now no data exist about the prognostic value of these examinations in a conservative therapeutic regimen. METHODS: In a quality assessment, we retrospectively evaluated the records of 90 patients, and performed an audiometric follow-up for analysis of long-time hearing data. All patients had undergone diagnostic electrocochleographic examination (ECochG) and then had been treated with rheologic infusions, followed by dehydrating infusions in patients lacking complete remission. The results of both therapeutic strategies and of long-time results were correlated to electrophysiologic findings. RESULTS: The prognosis of LFHI is significantly reflected by pretherapeutic electrocochleographic data. All significant parameters were associated to compound action potential (CAP) whereas parameters associated to cochlear microphonics (CM) did not include any utilizable prognostic value. In patients with a good outcome, the latency of CAP complex was significantly shorter, and the width of CAP complex significantly smaller than in patients with poor hearing outcome after rheologic and after dehydrating therapy and in long time assessment. The relation of summating potential (SP) und CAP was significantly smaller when the outcome was sufficient or good for either therapy and in long time analysis. Steep CAP-input-output-curves were associated to insufficient outcome after rheologic therapy and in long time assessment, but not for dehydrating therapy. CONCLUSIONS: The results indicate that ECochG is of significant prognostic value concerning hearing outcome after conservative therapy in patients suffering from LFHI. It can help the physician to counsel the patient and perform an effective management of the disease. We conclude that ECochG should be performed before the onset of therapy, including collection of SP and CAP data whereas CM parameters may be omitted.

Action Potentials↗
PubMed2005

[The voice evaluation protocol of the European Laryngological Society (ELS) -- first results of a multicenter study].

INTRODUCTION: A multidimensional protocol has been established by the ELS in order to reach better agreement and standardisation for functional assessment of pathologic voices. In order to evaluate the validity, practicability and applicability of this protocol the experiences of 6 european voice centres have been analysed in a retrospective study. MATERIAL AND METHODS: The ELS protocol comprises 5 dimensions: perceptual voice evaluation, videostroboscopy, acoustics, aerodynamics and subjective rating by the patient. Results obtained in 94 patients with benign voice disorders were evaluated retrospectively in a multicenter study. RESULTS: According to our results, the validity, practicability and applicability of the ELS protocol was largely satisfactory. This was true for all "common" voice disorders, but not for extreme voice alterations (e. g. spasmodic dysphonia, aphonia, substitution voices). The 5 dimension proofed to be not redundant and were able to selectively differentiate pre- post changes among various etiologies of voice disorders, various types of treatment and genders.

Adolescent↗
PubMed2005

A holistic approach to voice therapy.

Therapy approaches designed to improve the disordered voice may be equally effective when used to enhance the normal voice. A holistic approach to voice therapy is based on a continuum of voice wellness from the disordered voice to the elite voice of the healthy performer. Individuals take charge of the wellness of their voices by following good principles of vocal hygiene and exercising the vocal mechanism in a healthful manner. All voices may be improved on this continuum toward the ideal. When voice therapy techniques attend to the three subsystems of voice production, respiration, and phonation and resonance, the techniques fall into the category of holistic voice therapies. Vocal Function Exercises is one holistic voice therapy approach that has been found to be effective in improving those with voice disorders and enhancing the normal voice. This article introduces the concept of holistic voice therapy and describes the specific Vocal Function Exercise Program.

Holistic Health↗
PubMed2006

[Multiparametric description of voice quality for normal male and female voices based on acoustic analyses].

BACKGROUND: An improved method to obtain voice quality parameters from the acoustic speech signal is presented and applied to the determination of voice profiles. METHODS: The method is based on voice parameters proposed by Stevens and Hanson (1994). Vowel productions of 300 adult speakers (150 male and 150 female speakers) without any known voice pathologies were considered. RESULTS: In a first step, gender differentiated mean normal voice profiles are presented. The significant differences between male and female speakers indicate the necessity for separate treatment of the two groups. In a second step, a clustering technique differentiates three numerically substantial subgroups for male and female speakers. Over and above that, the acoustic parameters with the best potential for subgroup differentiation are determined. Additionally, a continuum containing individual variation within normal phonation is shown. CONCLUSIONS: The relevance of the analysis method is supported by the possibility of a physiological interpretation of the voice data.

Adolescent↗
PubMed1998

[Paralysis of the superior laryngeal nerve after whiplash trauma].

BACKGROUND: The current literature rejects the possibility of strain of the superior laryngeal nerves by whiplash injury. However, due to the anatomic situation and the mechanism of the whiplash injury this damage does not seem unlikely. PATIENT: A 58-year-old male patient, who was a trained singer, complained of a loss of his head voice following a major whiplash injury. Indirect laryngoscopy revealed no unusual findings. The phoniatric examination showed a loss of the head voice in the vocal field indicating paresis of the superior laryngeal nerves. Three and one-half months after the whiplash injury, the paresis had completely receded and the patient had a voice well above average with an excellent frequency range. CONCLUSIONS: In the case presented the paresis of the superior laryngeal nerves could have been caused by a strain of the nerves during whiplash injury. A complete and exact phoniatric diagnosis can be recommended for elderly patients complaining of an altered voice following whiplash injury.

Follow-Up Studies↗
PubMed1998

[External vocal cord medialization: functional outcome].

BACKGROUND: Comprehensive evaluation of voice function is the precondition for indication and quality control of every phonosurgical procedure. In 53 patients presenting with glottic insufficiencies of different etiologies an external vocal fold medialisation was performed. Functional voice results obtained with this operation are presented and discussed. METHODS: The following voice parameters were measured preoperatively and postoperatively, and statistical comparison was performed: mean fundamental frequency and sound pressure level, frequency and intensity range (voice range profile), perceptual evaluation of hoarseness, and maximum phonation time. The impairment of vocal communication skills was rated on a newly developed 7-point scale. A combined parameter called "Voice Dysfunction Index" was introduced for global assessment of vocal abilities in particular for long term observations. RESULTS: Statistically significant improvement of all voice parameters was demonstrated. Interestingly, in nearly all measurements male patients yielded significantly better results than females. Glottic insufficiencies due to scarring produced poorer functional results but without statistical significance. A statistically significant correlation between the preoperative and postoperative Voice Dysfunction Index could be observed. This score was also significantly correlated with the degree of glottal gap. No significant correlation between voice results and preoperative delay or follow-up period were observed. Voice therapy was performed in 81% of the patients. Correlation of duration of voice therapy and voice results was statistically significant and negative. Analysis of this surprising result showed that it was caused by some patients with vocal fold scarring in whom outcome was poor despite a long period of voice therapy. CONCLUSIONS: Significant improvement of vocal function can be obtained by external vocal fold medialization in patients with glottic insufficiencies. Glottal gaps caused by vocal fold scarring and/or atrophy can be treated with this method, too. However, results are not as good as in paralysis and require additional long term voice therapy. Satisfying results can be expected in patients with a long history of disturbances, and in older patients. Due to the reversibility of the operation, external vocal fold medialization can be performed even in cases of palsy prior to the spontaneous recovery period. The degree of glottic gap determines the functional disturbance. The degree of the preoperative impairment correlates with the outcome. Results are stable with respect to the follow-up period (mean 66 weeks).

Adult↗
PubMed1998

[Effect of stimulus rise time and high-pass masking on early auditory evoked potentials].

BACKGROUND: Problems of frequency-specific objective assessment of hearing threshold by means of auditory brainstem response (ABR) have been discussed recently. While a number of workers have recommended methods of selective masking to improve the frequency specificity, others believe that frequency-specific potentials can also be obtained without masking. In this context, the effects of rise-decay time and high-pass masking on ABRs were investigated. METHOD: ABRs were recorded in normal-hearing subjects and patients with high and low frequency hearing loss by means of surface electrodes between the vertex and the ipsilateral mastoid. The frequency of the stimulus was 1 kHz, and the rise-decay time 1 ms (1-0-1) or 2 ms (2-0-2). High-pass filtered noise (cutoff frequency 1.5 kHz; filter slope 250 dB/octave) was employed for masking. Particular attention was paid to the problem of efficient masking. RESULTS: In normal-hearing subjects under the influence of high-pass masking compared to non-masked ABRs, longer mean latencies and diminished means of the amplitudes of wave V were found, with differences in the near-threshold domain being less pronounced. Similar results were observed in patients with high frequency hearing loss. In patients with low frequency hearing loss, the influence of high-pass masking was especially marked distinctly near to threshold. Furthermore, latency and amplitude differences of wave V of the 1-0-1 and the 2-0-2 stimuli were determined from the ABRs obtained with and without high-pass masking. The differences between the latency differences of both stimuli in the suprathreshold range (70 dB nHL) only were statistically significant. CONCLUSIONS: The results are suggestive of an inadequate frequency specificity of unmasked stimuli in the suprathreshold range. Evaluation of the latencies revealed for both rise-decay times a similar frequency specificity near the threshold and a higher frequency specificity of the longer stimulus in the suprathreshold range.

Acoustic Stimulation↗