Martin Ptok
Hannover Medical School
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Featured researches published by Martin Ptok.
International Journal of Pediatric Otorhinolaryngology | 1999
R. Schönweiler; Jörg A. Lisson; Bettina Schonweiler; A. Eckardt; Martin Ptok; Joachim Tränkmann; Jarg-Erich Hausamen
Many cleft palate teams currently schedule palatoplasty and veloplasty within the childs 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.
International Journal of Pediatric Otorhinolaryngology | 1998
R. Schönweiler; Martin Ptok; H.-J Radü
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.
International Journal of Pediatric Otorhinolaryngology | 1996
R. Schönweiler; S. Kaese; Sebastian Möller; A. Rinscheid; Martin Ptok
Neuronal networks are computer-based techniques for the evaluation and control of complex information systems and processes. So far, they have been used in engineering, telecommunications, artificial speech and speech recognition. A new approach in neuronal network is the self-organizing map (Kohonen map). In the phase of learning, the map adapts to the patterns of the primary signals. If, the phase of using the map, the input signal hits the field of the primary signals, it resembles them and is called a winner. In our study, we recorded the cries of newborns and young infants using digital audio tape (DAT) and a high quality microphone. The cries were elicited by tactile stimuli wearing headphones. In 27 cases, delayed auditory feedback was presented to the children using a headphone and an additional three-head tape-recorder. Spectrographic characteristics of the cries were classified by 20-step bark spectra and then applied to the neuronal networks. It was possible to recognize similarities of different cries of the same children as well as interindividual differences, which are also audible to experienced listeners. Differences were obvious in profound hearing loss. We know much about the cries of both healthy and sick infants, but a reliable investigation regimen, which can be used for clinical routine purposes, has yet not been developed. If, in the future, it becomes possible to classify spectrographic characteristics automatically, even if they are not audible, neuronal networks may be helpful in the early diagnosis of infant diseases.
Orphanet Journal of Rare Diseases | 2015
Michaela Thoenes; Ulrike Zimmermann; Inga Ebermann; Martin Ptok; Morag A. Lewis; Holger Thiele; Susanne Morlot; Markus Hess; Andreas Gal; Tobias Eisenberger; Carsten Bergmann; Gudrun Nürnberg; Peter Nürnberg; Karen P. Steel; Marlies Knipper; Hanno J. Bolz
BackgroundEarly-onset hearing loss is mostly of genetic origin. The complexity of the hearing process is reflected by its extensive genetic heterogeneity, with probably many causative genes remaining to be identified. Here, we aimed at identifying the genetic basis for autosomal dominant non-syndromic hearing loss (ADNSHL) in a large German family.MethodsA panel of 66 known deafness genes was analyzed for mutations by next-generation sequencing (NGS) in the index patient. We then conducted genome-wide linkage analysis, and whole-exome sequencing was carried out with samples of two patients. Expression of Osbpl2 in the mouse cochlea was determined by immunohistochemistry. Because Osbpl2 has been proposed as a target of miR-96, we investigated homozygous Mir96 mutant mice for its upregulation.ResultsOnset of hearing loss in the investigated ADNSHL family is in childhood, initially affecting the high frequencies and progressing to profound deafness in adulthood. However, there is considerable intrafamilial variability. We mapped a novel ADNSHL locus, DFNA67, to chromosome 20q13.2-q13.33, and subsequently identified a co-segregating heterozygous frameshift mutation, c.141_142delTG (p.Arg50Alafs*103), in OSBPL2, encoding a protein known to interact with the DFNA1 protein, DIAPH1. In mice, Osbpl2 was prominently expressed in stereocilia of cochlear outer and inner hair cells. We found no significant Osbpl2 upregulation at the mRNA level in homozygous Mir96 mutant mice.ConclusionThe function of OSBPL2 in the hearing process remains to be determined. Our study and the recent description of another frameshift mutation in a Chinese ADNSHL family identify OSBPL2 as a novel gene for progressive deafness.
Jaro-journal of The Association for Research in Otolaryngology | 2000
R. Schönweiler; Markus Hess; Peter Wübbelt; Martin Ptok
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.
Journal of medical imaging | 2015
Sabine Donner; Sebastian Bleeker; Tammo Ripken; Martin Ptok; Michael Jungheim; Alexander Krueger
Abstract. Optical coherence tomography (OCT) provides structural information of laryngeal tissue which is comparable to histopathological analysis of biopsies taken under general anesthesia. In awake patients, movements impede clinically useful OCT acquisition. Therefore, an automatic compensation of movements was implemented into a swept source OCT-laryngoscope. Video and OCT beam path were combined in one tube of 10-mm diameter. Segmented OCT images served as distance sensor and a feedback control adjusted the working distance between 33 and 70 mm by synchronously translating the reference mirror and focusing lens. With this motion compensation, the tissue was properly visible in up to 88% of the acquisition time. During quiet respiration, OCT contrasted epithelium and lamina propria. Mean epithelial thickness was measured to be 109 and 135u2009u2009μm in female and male, respectively. Furthermore, OCT of mucosal wave movements during phonation enabled estimation of the oscillation frequency and amplitude. Regarding clinical issues, the OCT-laryngoscope with automated working distance adjustment may support the estimation of the depth extent of epithelial lesions and contribute to establish an indication for a biopsy. Moreover, OCT of the vibrating vocal folds provides functional information, possibly giving further insight into mucosal behavior during the vibratory cycle.
Annals of Otology, Rhinology, and Laryngology | 2015
Michael Jungheim; Alexander Matthias Janhsen; Simone Miller; Martin Ptok
Objectives: Beside traditional dysphagia therapy, neuromuscular electrical stimulation (NMES) has been proposed to treat patients with dysphagia. Considering the complexity of the nerve-muscle interaction during swallowing, the underlying physiology of NMES remains unclear. Here, we addressed the question of whether NMES can modify upper esophageal sphincter (UES) dynamics. Methods: In a prospective study, 26 healthy volunteers performed water swallows with and without NMES. The stimulus was applied in a participant- and operator-initiated stimulation above, near, and below the motor threshold. Swallowing parameters were measured using high-resolution manometry. Results: The UES relaxation time was found to be extended by 10%, indicating a modification in UES dynamics. Conclusions: The chosen NMES paradigm influenced the involuntary swallowing phase by extending relaxation time, providing more time for bolus passage into the esophagus. Future studies will have to evaluate if this effect can be found in patients with dysphagia and whether it is beneficial for treatment.
Folia Phoniatrica Et Logopaedica | 2013
Simone Miller; Michael Jungheim; D. Kühn; Martin Ptok
Objective: Neuromuscular electrical stimulation (NMES) has been proposed in the treatment of laryngopharyngeal dysfunctions (dysphonia, dyspnoea, dysphagia) for more than 40 years. Several studies have investigated possible therapeutic effects. Some researchers described favourable results, whereas others did not find relevant benefits. This article aims to review available studies to give an overview regarding the current state of knowledge. Methods: We conducted a selective literature search using PubMed. Results: In total, 356 papers were identified: 6 case reports, 11 reviews, 43 prospective clinical trials and 3 retrospective trials were found. Conclusion: Due to different stimulation protocols, electrode positioning and various underlying pathological conditions, summarizing the present studies appears to be difficult. However, there is evidence that NMES is a valuable adjunct in patients with dysphagia and in patients with vocal fold paresis. Nevertheless, more empirical data is needed to fully understand the benefits provided by NMES. Further research suggestions are put forward.
Oral and Maxillofacial Surgery | 2011
Corinna Bergmann; Susanne Spranger; Poupak Javaher; Martin Ptok
IntroductionGenitopatellar syndrome is characterized by absent/hypoplastic patellae, genital and renal abnormalities, dysmorphic facial features, and mental retardation. Cardiac anomalies, ectodermal dysplasia, and radio-ulnar synostosis have been suggested as additional features.DiscussionWe report on additional female patient with sensorineural hearing loss, cleft palate, and hypothyroidism in addition to known anomalies. Findings are discussed based on a literature review of the known patients with the genitopatellar syndrome.
International Journal of Pediatric Otorhinolaryngology | 2014
C. Schwemmle; Imma Rost; Stephanie Spranger; Michael Jungheim; Martin Ptok
The investigation of patients with congenital anomalies and/or intellectual disability with modern genetic methods allows the recognition of an increasing number of cases with these chromosomal rearrangements. Here, we present a mildly mentally retarded boy with mild facial dysmorphism, language development delay, mild sensorineural hearing loss due to a deletion of 1,14 Mb on chromosome 19p 13.2. The deletion was de novo and familial history negative for this disorder. To our knowledge this is the first description of a patient with symptoms mentioned above associated with a 19p13.2-p13.2 deletion.