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M Ptok

Publications and source records attributed to M Ptok.

At least 19 recordsLinked to original sources
PubMed2003

[Long-term results after velopharyngoplasty].

BACKGROUND: Children with cleft palate frequently demonstrate speech and resonance disorders following primary cleft repair. In some patients no improvement can be achieved with conservative therapy and a velopharyngoplasty (VPP) may be indicated. This study was performed to evaluate the long-term results after VPP. MATERIAL AND METHODS: Twenty-six patients were followed up on an average 9 years after VPP (mean age: 16+/-5 years). Apart from the phoniatric-pedaudiologic findings, the speech intelligibility and nasality were judged by speech pathologists and by laymen. The extent of the speech handicaps was evaluated with a questionnaire. The nasalance was measured with NasalView. The vowels, two test sentences, and three reading texts (LT(1-3)) were used as test materials. RESULTS: The phoniatric-pedaudiologic examination revealed a clear improvement of hearing, language, and speech function. Compared to the previous results, decreased nasality and improved ability in articulation were detected. The judgment of laymen was also positive. The speech intelligibility was mostly evaluated as favorable. A speech handicap was present in only a few patients. The evaluation using NasalView showed significantly increased nasalance values for the LT(2) ( p=0.030). Moreover there were lower nasalance values for all the reading texts compared to the control group (LT(1) p=0.257, LT(2) p=0.408, LT(3) p=0.187). CONCLUSION: A clear improvement can be achieved with VPP in patients with a high degree of therapy-resistant nasality. In many cases even normal colloquial language is possible. The evaluation of nasalance has proved to be successful for rating surgical outcome.

Adolescent↗
PubMed2003

[Normal nasalance for the German language. Nasometric values for clinical use in patients with cleft lip and palate].

OBJECTIVE: Rhinophonia is often present in patients with cleft lip and palate (CLP) many years after palatoplasty. It may be caused either by organic deficits, functional disorders, or both. NasalView is known as an instrument for the objective assessment of nasalance in cases of velopharyngeal insufficiency or incompetence.However,normative values for the German language are not yet available. In order to overcome this problem, this study evaluated such norms using NasalView. METHODS: A total of 50 individuals with normal speech development were examined with NasalView. The median age was 14 years (range 11-20 years). The tone material used comprised the vowels /a:/, /e:/, /i:/, /o:/, /u:/, the sentences S(1): "Die Schokolade ist sehr lecker."("This chocolate is very tasty.") and S(2): "Nenne meine Mamma Mimmi."("Call my mummy Mimmi."), and the text passages of LT(1): "Nordwind und Sonne"("Northwind and sun"), LT(2): "Kindergeburtstag"("A child's birthday party") and LT(3): "Der grosse Gesang"("A famous song"). RESULTS: The mean nasalance for the vowels was 35.9% (+/-8.4), for S(1) (containing no nasal consonants) 24.9% (+/-5.3), and for S(2) 69.6% (+/-5.5) (with many nasal sounds). The results for the text passages were 42.1% (+/-4.2) for LT(1), 36.9% (+/-4.3) for LT(2) and 38.2% (+/-4.4) for LT(3). CONCLUSION: The norms of nasalance for the German language presented here may be useful in measuring the long-term outcome of cleft lip and palate.

Adolescent↗
PubMed2003

Search for deletion 22q11.2 in interphase nuclei of buccal mucosa of patients ascertained by isolated cleft palate: a new diagnostic approach.

A new approach for the detection of chromosome deletion 22q11.2 in interphase nuclei from buccal mucosa cells obtained by a non-invasive procedure is described. FISH analysis has been performed on samples from a group of 101 patients that presented consecutively for speech therapy and/or surgical correction of cleft palate. A normal result has been obtained in 98 patients; a deletion 22q11.2 was present in three patients (2.8%) with cleft palate.

Adolescent↗
PubMed2002

[Hearing screening with automatic evaluation of TEOAE and a new method of automatic evaluation of early auditory evoked potentials. Optimization and field trial].

BACKGROUND AND OBJECTIVE: To make a rational decision as to which screening test might be adequate as a universal newborn hearing screening, different methods have to be tested under "real-life" conditions. In addition, a good reference is required as "golden standard." PATIENTS/METHODS: In the study presented here, an ABR with a novel algorithm for threshold-estimation was optimized and compared to TEOAE (Echoscreen) and DPOAE (GSI 60) in a three-step protocol using a standard click-evoked ABR (Evoselect) as reference of sensitivity and specificity. RESULTS: 26 ears were found to be hearing-impaired. All of them were also detected by each of the screening method (sensitivity 100%). Specificity in the final "step 2" of the study was around 87.7/92.3% for Echoscreen, 82.4/84.4% for DPOAE and 82.4/89.1 for Evoflash (left/right, respectively). Differences were not at all significant (X2-test, p > > 0.05). In summary, results were somewhat inferior to those found by other authors, probably due to more difficult conditions in the "real-life" setting. CONCLUSIONS: A higher rate of false-alarm shows that a two-step screening is necessary. Therefore, increased resources for diagnostic procedures are required.

Adolescent↗
PubMed2002

[Signal detection theoretical aspects of various threshold detection procedures].

Psychoacoustic threshold detection measurements are widely used in clinical and research applications. A variety of procedures has been described to measure psychoacoustic thresholds. Each of these procedures has advantages and disadvantages. For clinical purposes procedures providing fast results may be preferred whereas for psychoacoustic research the threshold has to be determined as exactly as possible. Conventional procedures are based on a yes/no paradigm. Since these procedures are influenced by criterion shifts, n-alternative forced choice procedures were developed. Here the patient has to indicate the interval most likely to contain the signal. Additionally, it is possible to estimate the threshold based upon few data and comparing these to known psychometric functions. Following an overview outlining procedural aspects of threshold detection methods aspects of signal detection theory in relation to these procedures are discussed. Signal detection theory may help to explain why results obtained with various procedures may be quite different.

Audiometry, Pure-Tone↗
PubMed2002

[Decision processes at threshold levels during psychoacoustic testing].

Psychoacoustic threshold detection measurements are widely used in clinical and research applications. Usually, a threshold is considered as that intensity of the signal above which the stimulus is detected by the patient and below it will be not. However, this definition is unsatisfactory since there is no such well defined amount of intensity above which the signal suddenly becomes detectable. Rather at intensities close to the "threshold" the patient will be more or less sure to have heard the signal. The more the intensity is increased the more the patient becomes convinced. This paper aims at providing insight into some basics about signal detection close to threshold especially psychometric functions and signal detection theory. It is shown that threshold detection for a given subject not only depends on signal parameters, the subject's co-operation, and on competence of the examiner but also to a great extent on the procedure chosen for estimating the threshold.

Audiometry, Pure-Tone↗
PubMed2001

Suggestion for orthodontic and speech improving measures in CLP patients.

The objective of the present paper is to describe a soft palate level device, the veloretractor, which is a combination of orthodontic appliance and therapeutic aid in speech therapy. Its use is demonstrated in a case report of a child with complete bilateral cleft lip and palate. Both orthodontic and phoniatric/pedaudiologic treatment needs during the course are demonstrated along with the treatment results.

Age Factors↗
PubMed2001

[Intensive inpatient therapy of auditory processing and perceptual disorders in childhood].

UNLABELLED: PRELIMINARY REMARKS: The prevalence of central auditory processing disorders (CAPD) is supposed to be 2-3% of all children. Given the number of affected children and restricted resources in the public health there is a need for an effective and evaluated therapeutic approaches. On the other hand the number of outcome studies is remarkably small. PATIENTS AND METHODS: The presented study reports strategies and pitfalls in outcome measurements of 34 children with CAPD, based upon a 3-weeks indoor therapeutic intervention. Diagnostic criteria of auditory processing and perception were recorded before and after therapy. RESULTS: The data shows a highly significant improvement of certain perceptive abilities, including audiological parameters (dichotic testing, discrimination, loudness scaling) and awareness, psycholinguistic development and orthographic tests. CONCLUSION: The study demonstrates that an effective therapy of CAPD in children is possible and scientifically proven. Long term surveillance however seems to be necessary. It also has to be studied whether intensive indoor treatment is superior or equal to out clinic therapy.

Auditory Perceptual Disorders↗
PubMed2001

[Botulinum toxin type A-induced "rebalancing" in bilateral vocal cord paralysis?].

BACKGROUND: Upper airway obstruction due to bilateral vocal cord paralysis in an 80-year-old female patient was successfully relieved by injection of botulinum toxin A (BTA) into the laryngeal adductor muscles. The patient achieved satisfactory airway ventilation. Spirograms obtained preoperatively and postoperatively documented improved peak flow rates and 1-s forced expiratory volume values. Voice quality was breathy after the injection; however, neither aspiration nor dysphagia developed. Surprisingly, the maximum phonation time increased. PATIENTS AND METHODS: During a follow-up check 4 months later, the patient still reported less dyspnea although the vocal cords were closer together than initially after the injection. The decrease in dyspnea as reported by the patient lasted approximately 2 years. RESULTS: The improvement in breathing following injection of BTA can be interpreted as a paralysis or weakening of the laryngeal adductors. However, it remains unclear why the maximum phonation time increased. Comparable findings, i.e., improvement in overall laryngeal function, are described in the literature as BTA-mediated laryngeal rebalancing.

Aged↗
PubMed2001

[Psychoacoustic scaling of acoustic voice parameters by multicenter voice ratings].

BACKGROUND: The purpose of the study was to analyze if perceptual voice quality ratings of the well-known RBH rating procedure (a 4-point scale of roughness, breathiness, and hoarseness) covary with acoustical voice parameters. METHODS: 120 voice samples from subjects with healthy and hoarse voices were rated on the RBH-index in a multicenter study with 31 raters. Multivariate regression tree analysis classified the perceptual ratings as "gold standard". Voice samples were acoustically analyzed with a feature extraction method. Feedforward-networks were trained to selected acoustical parameters having highest "relative importance" in the regression trees. Based on the best classifier, a computer program consisting of 50 simultaneous working networks was developed. RESULTS: Mean probabilities for correct classifications were found at 0.65-0.85, implying a significance level over chance (0.25). Classifications of the program matched in 40% with a priori values in the categories roughness combined with breathiness, and in 65% in at least one domain. CONCLUSIONS: The new method described here provides a psychoacoustically based "objective" classification of hoarse voices, which seems to enable future analysis of new parameters (like GNE), which may even improve the present results.

Acoustics↗
PubMed2000

[Otoacoustic emissions, auditory evoked potentials, pure tone thresholds and speech intelligibility in cases of auditory neuropathy].

The combined findings of "normal evoked otoacoustic emissions (EOAE) and absent or markedly disturbed auditory evoked potentials from the brainstem and/or cortex" has been named auditory neuropathy in the English literature. The pure tone thresholds in these patients range from mild to severe loss. The loss of speech comprehension is out of proportion in comparison to the pure tone threshold elevation. This combination of findings suggests that cochlear function and in particular outer hair cell function, is normal in these patients but also suggests that the inner hair cell / VIII nerve functional unit is abnormal. Disruption in neural synchrony has previously been postulated as a reasonable explanation for the absent auditory brainstem response while otoacoustic emissions are preserved. Because the long-latency auditory evoked potentials, not having the stringent synchrony requirements of the ABR, may also be missing, the term synchrony - disruption may be somewhat misleading. The literature about auditory neuropathy is reviewed here: We now know that a set of salient features distinguishes these patients from the majority of patients with sensorineural hearing loss or other described syndromes. The symptoms defining auditory neuropathy are mild, moderate or severe elevation of auditory thresholds to pure tone stimuli by air and bone conduction, absent to severely abnormal ABRs to high level stimuli, present otoacoustic emissions (that do not suppress with contralateral noise), word recognition ability poorer than expected from the pure tone hearing loss configuration (in cases with mild to moderate hearing threshold elevation) and absent acoustic reflexes to both ipsilateral and contralateral tones. The entire set of findings, consistently seen in these patients, supports the importance of the crosscheck principle in diagnostic evaluation especially in children with delayed and/or impaired language acquisition. It is of ponderous importance that this disorder is not being confused with sensory hearing loss.

Adult↗
PubMed2000

[Sensorineural hearing loss in distal renal tubular acidosis, nephrocalcinosis and microcytic anemia].

Distal renal tubular acidosis is characterized by an impaired H(+)-ion secretion in the distal tubulus. This may cause metabolic acidosis. Among others, patients suffer from retardation and nephrocalcinosis. Here we report about a 3 years old patient with drtA and sensorineural hearing loss. ATP6B1 gene mutation was recently found in patients with drtA sensorineural hearing loss. ATP6B1 expression was demonstrated immunohistochemically in the mouse cochlea and endolymphatic sac. ATP6B1 mRNA was found in the fetal and adult human cochlea. These findings suggest that sensorineural hearing loss in drtA is caused by an disturbed pH homeostasis induced by ATP6B1 mutation.

Acidosis, Renal Tubular↗
PubMed2000

Novel approach to acoustical voice analysis using artificial neural networks.

Perceptual rating scales are widely used for the assessment of voice quality. These ratings may be influenced by the individual experience of the listener. Thus, researchers have turned to acoustical measures which may eventually correlate with voice quality. In this study we tested whether multivariate statistics, combined with artificial neural networks, could identify patterns of acoustic voice parameters corresponding to a widely used perceptual rating scale. In a multicenter study with 31 raters, voice samples of 117 individuals with or without voice disorders were perceptually rated. The RBH index, consisting of a 4-point scale of roughness, breathiness, and hoarseness, was used. Voice samples were then analyzed with an acoustical feature extraction and classified using amultivariate regression tree analysis with the perceptual ratings as a priori information. Artificial neural networks were trained to selected acoustic parameters having high "relative importance" in the regression trees. Mean classification accuracies were around 30% with topographic feature maps (trained with Learning Vector Quantization algorithm) and 65-85% with feedforward networks (trained with RProp algorithm). Based on the best-fitting results with feedforward networks, a classification system (computer program) consisting of 50 simultaneous working networks was developed. Using this program, the classification matched 40% of the a prori values in both R and B domains. In 65% they matched at least in one domain. These accuracies are within the range reported by other authors using artificial neural networks in biology and clinical medicine. Thus, the results encourage further research of feedforward networks for acoustic voice analysis.

Humans↗
PubMed1999

A retrospective study of hearing, speech and language function in children with clefts following palatoplasty and veloplasty procedures at 18-24 months of age.

Many cleft palate teams currently schedule palatoplasty and veloplasty within the child's first year of life. At Hannover Medical School, palatoplasty and veloplasty are performed at approximately 18-24 months of age. It was questioned which speech and language outcome was achieved and whether it may be influenced by: (1) type and extent of the clefts; (2) velopharyngeal inadequacy; and (3) hearing disorders. A retrospective evaluation of data collected from 1985 to 1993 was performed summarizing receptive and expressive speech and language skills of 370 children aged 4.5 years. Cleft types were unilateral cleft lip and palate (UCLP, 30.0%), bilateral cleft lip and palate (BCLP, 28.7%), cleft hard and soft palate (CP, 21.6%), cleft soft palate (cleft velum, CV, 10.8%), cleft lip and alveolus (CLA, 5.8%) and submucous clefts (SUB, 3.2%). n = 86 had constant normal hearing, and n = 284 had conductive hearing loss > 20 dB (500-4000 Hz). Severe developmental phonology errors were found in 30-50% of children with repaired cleft palate and in less than 8% of patients with CLA and SUB. Posterior compensatory misarticulation was below 15% in the groups UCLP, BCLP, CP, CV and SUB. Nasal resonance and air emission was nearly normal in CLA, but was increased in 27% to 38% of the other cleft types. Children with conductive hearing loss had significantly more and severely affected phonology, morphology, syntax, vocabulary, language comprehension, and auditory perception than normal hearing children. Findings indicated that speech and language function in CLP patients were predominantly related to the hearing status.

Articulation Disorders↗
PubMed1998

A cross-sectional study of speech- and language-abilities of children with normal hearing, mild fluctuating conductive hearing loss, or moderate to profound sensoneurinal hearing loss.

A total of 1528 pre-school children (mean age 4 years and 9 months), being identified as speech or language delayed, were evaluated with respect to micro-otoscopy, nose and throat pathology, hearing function, and speech-language abilities. Subjects were classified into groups of (I) constant normal hearing, (II) fluctuating conductive hearing loss and (III) bilateral moderate to profound sensorineural hearing loss requiring hearing aids. In groups II and III, severe speech and language pathologies were found more frequently than in group I. Additionally, auditory perception skills were less in group II, even if peripheral hearing function was normalized. Group III was affected more than group II, but not significantly. The results indicate that in children having speech or language delay for severals reasons, mild fluctuating hearing loss can additionally alter language acquisition, but less than in cases of moderate or profound sensoneurinal hearing loss. The need of early detection of sensoneurinal hearing loss appears widely accepted; this study demonstrates also the necessity of early diagnosis of mild fluctuating hearing loss, especially in children with speech-language delay.

Acoustic Impedance Tests↗
PubMed1998

Supraglottal injection of botulinum toxin type A in adductor type spasmodic dysphonia with both intrinsic and extrinsic hyperfunction.

Patients with adductor type spasmodic dysphonia (SD) often exhibit both glottal and supraglottal hyperfunction. Based on the hypothesis that a "ventricular muscle" may contribute to the hyperfunction in these cases, eight patients with adductor type SD were treated with bilateral injection of botulinum toxin type A into the ventricular folds. Four weeks after injection, ventricular fold hyperfunction was absent in all cases. Number of voice breaks, standard deviation of fundamental frequency, and shimmer were significantly improved. Voice range profiles of the speaking voice were significantly extended in dynamic and frequency range. Side effects were a breathy phonation and mild swallowing difficulties without aspiration for about 1 week. Patients' self-rating concerning strangled and breathy voicing demonstrated an interval of acceptable voice quality between 1 week and 4 months after injection in all cases. Results suggest that supraglottal injection in patients with SD of both glottal and supraglottal hyperfunction, as a new approach, can normalize supraglottal activity and improve glottal voicing. Based on our experience with other patients with adductor type of SD, this injection technique is as efficient as injection into the thyroarytenoid muscle. Nevertheless, it remains to be proved that a pathologic ventricular muscle activity is addressed by this technique or if it is based on spreading to the thyroarytenoid muscle.

Acoustics↗