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Dive into the research topics where C. Arens is active.

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Featured researches published by C. Arens.


European Archives of Oto-rhino-laryngology | 2004

Indirect autofluorescence laryngoscopy in the diagnosis of laryngeal cancer and its precursor lesions

C. Arens; T. Dreyer; Hiltrud Glanz; K. Malzahn

Direct autofluorescence endoscopy of the larynx has proven to facilitate the detection and delineation of precancerous lesions, carcinoma in situ and cancer. The aim of the present study was to evaluate the diagnostic potential and limitations of this imaging technique applied during indirect laryngoscopy. In a prospective study, 116 patients with suspected precancerous or cancerous lesions were investigated preoperatively by indirect autofluorescence laryngoscopy. Autofluorescence was induced by filtered blue light (375–440xa0nm) of a xenon short-arc lamp and processed by a CCD camera system (D-light-AF System, Storz, Tuttlingen, Germany). Autofluorescence images were immediately assessed for diagnosis, compared to the direct autofluorescence picture obtained during microlaryngoscopy and compared to pathohistological findings. Comparable to direct autofluorescence images, normal laryngeal mucosa showed a typical green fluorescence signal. Moderate and high epithelial dysplasia, carcinoma in situ and cancer displayed a diminished green fluorescence. False negative results were related to extreme hyperkeratosis. False positive cases showed mild dysplasia with inflammatory reactions or scarring. In 103 cases (89%), we found concordant results. According to our results, the presented technique seems to be a promising diagnostic tool for the early detection of laryngeal cancer and its precursor lesions during indirect laryngoscopy. Scarring, marked hyperkeratosis and inflammation can limit the predictive value of the method.


European Archives of Oto-rhino-laryngology | 2012

Laryngeal electromyography: a proposal for guidelines of the European Laryngological Society

Gerd Fabian Volk; Rudolf Hagen; Claus Pototschnig; Gerhard Friedrich; Tadeus Nawka; C. Arens; Andreas Mueller; Gerhard Foerster; Mira Finkensieper; Ruth Lang-Roth; Christian Sittel; Claudio Storck; Maria Grosheva; M. Nasser Kotby; Carsten M. Klingner; Orlando Guntinas-Lichius

Although recognized as a valuable diagnostic tool for more than 60xa0years, many laryngologists do not routinely use laryngeal electromyography (LEMG). This may be due to a persisting lack of agreement on methodology, interpretation, validity, and clinical application of LEMG. To achieve consensus in these fields, a laryngeal electromyography working group of European neurolaryngologic experts was formed in order to (1) evaluate guidelines for LEMG performance and (2) identify issues requiring further clarification. To obtain an overview of existing knowledge and research, English-language literature about LEMG was identified using Medline. Additionally, cited works not detected in the initial search were screened. Evidence-based recommendations for the performance and interpretation of LEMG and also for electrostimulation for functional evaluation were considered, as well as published reports based on expert opinion and single-institution retrospective case series. To assess the data obtained by this literature evaluation, the working group met five times and performed LEMG together on more than 20 patients. Subsequently, the results were presented and discussed at the 8th Congress of the European Laryngological Society in Vienna, Austria, September 1–4, 2010, and consensus was achieved in the following areas: (1) minimum requirements for the technical equipment required to perform and record LEMG; (2) best practical implementation of LEMG; (3) criteria for interpreting LEMG. Based on this consensus, prospective trials are planned to improve the quality of evidence guiding the proceedings of practitioners.


European Archives of Oto-rhino-laryngology | 2013

Vocal fold scars: current concepts and future directions. Consensus report of the phonosurgery committee of the European laryngological society

Gerhard Friedrich; Frederik G. Dikkers; C. Arens; Marc Remacle; Markus Hess; Antoine Giovanni; S. Duflo; Anastasios Hantzakos; Vincent Bachy; Markus Gugatschka

Scarring of the vocal folds leads to a deterioration of the highly complex micro-structure with consecutively impaired vibratory pattern and glottic insufficiency. The resulting dysphonia is predominantly characterized by a reduced vocal capacity. Despite the considerable progress in understanding of the underlying pathophysiology, the treatment of scarred vocal folds is still an unresolved chapter in laryngology and phonosurgery. Essential for a successful treatment is an individual, multi-dimensional concept that comprises the whole armamentarium of surgical and non-surgical (i.p. voice therapy) modalities. An ideal approach would be to soften the scar, because the reduced pliability and consequently the increased vibratory rigidity impede the easiness of vibration. The chosen phonosurgical method is determined by the main clinical feature: Medialization techniques for the treatment of glottic gap, or epithelium freeing techniques for improvement of vibration characteristics often combined with injection augmentation or implantation. In severe cases, buccal mucosa grafting can be an option. New developments, include treatment with anxiolytic lasers, laser technology with ultrafine excision/ablation properties avoiding coagulation (Picosecond infrared laser, PIRL), or techniques of tissue engineering. However, despite the promising results by in vitro experiments, animal studies and first clinical trials, the step into clinical routine application has yet to be taken.


Journal of Immunology | 2014

CD4+ T Cells from Human Neonates and Infants Are Poised Spontaneously To Run a Nonclassical IL-4 Program

Katrin Hebel; Soenke Weinert; Benno Kuropka; Julienne Knolle; Bernhard Kosak; Gerhard Jorch; C. Arens; Eberhard Krause; Ruediger C. Braun-Dullaeus; Monika C. Brunner-Weinzierl

Senescence or biological aging impacts a vast variety of molecular and cellular processes. To date, it is unknown whether CD4+ Th cells display an age-dependent bias for development into specific subpopulations. In this study, we show the appearance of a distinct CD4+ T cell subset expressing IL-4 at an early stage of development in infant adenoids and cord blood that is lost during aging. We identified by flow cytometric, fluorescent microscopic, immunoblot, and mass spectrometric analysis a population of CD4+ T cells that expressed an unglycosylated isoform of IL-4. This T cell subpopulation was found in neonatal but not in adult CD4+ T cells. Furthermore, we show that the mRNA of the Th2 master transcription factor GATA3 is preferentially expressed in neonatal CD4+ T cells. The Th2 phenotype of the IL-4+CD4+ T cells could be reinforced in the presence of TGF-β. Although the IL-4+CD4+ T cells most likely originate from CD31+CD4+ T recent thymic emigrants, CD31 was downregulated prior to secretion of IL-4. Notably, the secretion of IL-4 requires a so far unidentified trigger in neonatal T cells. This emphasizes that cytokine expression and secretion are differentially regulated processes. Our data support the hypothesis of an endogenously poised cytokine profile in neonates and suggest a link between cytokine production and the developmental stage of an organism. The determination of the IL-4 isoform–expressing cells in humans might allow the identification of Th2 precursor cells, which could provide novel intervention strategies directed against Th2-driven immunopathologies such as allergies.


European Archives of Oto-rhino-laryngology | 2016

Proposal for a descriptive guideline of vascular changes in lesions of the vocal folds by the committee on endoscopic laryngeal imaging of the European Laryngological Society

C. Arens; Cesare Piazza; Mário Andrea; Frederik G. Dikkers; Robin E. A. Tjon Pian Gi; Susanne Voigt-Zimmermann; Giorgio Peretti

In the last decades new endoscopic tools have been developed to improve the diagnostic work-up of vocal fold lesions in addition to normal laryngoscopy, i.e., contact endoscopy, autofluorescence, narrow band imaging and others. Better contrasted and high definition images offer more details of the epithelial and superficial vascular structure of the vocal folds. Following these developments, particular vascular patterns come into focus during laryngoscopy. The present work aims at a systematic pathogenic description of superficial vascular changes of the vocal folds. Additionally, new nomenclature on vascular lesions of the vocal folds will be presented to harmonize the different terms in the literature. Superficial vascular changes can be divided into longitudinal and perpendicular. Unlike longitudinal vascular lesions, e.g., ectasia, meander and change of direction, perpendicular vascular lesions are characterized by different types of vascular loops. They are primarily observed in recurrent respiratory papillomatosis, and in pre-cancerous and cancerous lesions of the vocal folds. These vascular characteristics play a significant role in the differential diagnosis. Among different parameters, e.g., epithelial changes, increase of volume, stiffness of the vocal fold, vascular lesions play an increasing role in the diagnosis of pre- and cancerous lesions.


Hno | 2012

Fortschritte der endoskopischen Diagnostik von Dysplasien und Karzinomen des Larynx

C. Arens; U. Vorwerk; T. Just; Christian S. Betz; M. Kraft

ZusammenfassungZur Verbesserung der prä- und intraoperativen Diagnostik des Larynxkarzinoms und seiner Vorstufen sind in den letzten Jahren verschiedene endoskopisch bildgebende Verfahren entwickelt worden. Diese Techniken unterscheiden sich deutlich in der spezifischen Anwendung und der abgeleiteten Fragestellung. Eine genaue Unterscheidung zwischen normaler Schleimhaut, Dysplasie und invasivem Karzinom durch Anwendung dieser Verfahren ist notwendig. Darüber hinaus sollte die genaue Identifikation der Tumorränder möglich sein. Langfristiges Ziel der Entwicklungen ist die optische Biopsie. Da bisher nur kleinere Studien bzgl. der Evaluation der besprochenen Techniken existieren, ist es notwendig, Multizenterstudien mit großen Fallzahlen zu etablieren, um die Wertigkeit der endoskopisch bildgebenden Verfahren genau einschätzen zu können.AbstractTo improve the preoperative and intraoperative diagnosis of laryngeal cancer and its precursors, various endoscopic imaging techniques have been developed in recent years. These techniques differ markedly in their specific applications and goals. Precisely distinguishing among normal mucosa, dysplasia and invasive carcinoma with these procedures is necessary. Furthermore, the exact identification of tumor margins should be possible. The long-term goal is the development of optical biopsy. Since so far there have only been small studies regarding the evaluation of the presented methods, it is necessary to establish multi-center trials with large sample sizes to accurately estimate the value of these endoscopic imaging techniques.To improve the preoperative and intraoperative diagnosis of laryngeal cancer and its precursors, various endoscopic imaging techniques have been developed in recent years. These techniques differ markedly in their specific applications and goals. Precisely distinguishing among normal mucosa, dysplasia and invasive carcinoma with these procedures is necessary. Furthermore, the exact identification of tumor margins should be possible. The long-term goal is the development of optical biopsy. Since so far there have only been small studies regarding the evaluation of the presented methods, it is necessary to establish multi-center trials with large sample sizes to accurately estimate the value of these endoscopic imaging techniques.


Laryngoscope | 2015

Voice and respiratory outcomes after permanent transoral surgery of bilateral vocal fold paralysis.

Tadeus Nawka; Christian Sittel; C. Arens; Ruth Lang-Roth; Claus Wittekindt; Rudolf Hagen; Andreas Mueller; Ahmed I. Nasr; Orlando Guntinas-Lichius; Gerhard Friedrich; Markus Gugatschka

Bilateral vocal fold paralysis (BVFP) is a rare but life‐threatening condition mostly caused by iatrogenic damage to the peripheral recurrent laryngeal nerve. Endoscopic enlargement techniques have been the standard treatment for decades. However, prospective studies using internationally accepted phoniatric and respiratory evaluation guidelines are rare.


Laryngoscope | 2015

Permanent transoral surgery of bilateral vocal fold paralysis: A prospective multi‐center trial

Tadeus Nawka; Christian Sittel; Markus Gugatschka; C. Arens; Ruth Lang-Roth; Claus Wittekindt; Rudolf Hagen; Andreas H. Müller; Gerd Fabian Volk; Orlando Guntinas-Lichius

To describe postoperative adverse events (AEs) and outcomes after transoral surgery for bilateral vocal fold paralysis (BVFP).


Hno | 2017

Narrow band imaging for early diagnosis of epithelial dysplasia and microinvasive tumors in the upper aerodigestive tract

C. Arens; Christian S. Betz; M. Kraft; Susanne Voigt-Zimmermann

The various stages of tumor growth are characterized by typical epithelial, vascular, and secondary connective tissue changes. Narrow Band Imaging (NBI) endoscopy is axa0minimally invasive imaging technique that presents vascular structures in particular at axa0higher contrast than white light endoscopy alone. In combination with high-resolution image recording and reproduction (high-definition television, HDTV; ultra-high definition, 4K), progress has been made in otolaryngological differential diagnostics, both pre- and intraoperatively. This progress represents an important step toward axa0so-called optical biopsy. Flexible endoscopy in combination with NBI allows for a detailed assessment of areas of the upper aerodigestive tract that are difficult to assess by rigid endoscopy. Papillomas along with precancerous and cancerous lesions are characterized by epithelial and connective tissue changes as well as by typical perpendicular vascular changes. Systematic use of NBI is recommended in the differential diagnosis of malignant lesions of the upper aerodigestive tract. NBI also offers axa0significant improvement in the pre- and intraoperative assessment of superficial resection margins. In particular, the combination of NBI and contact endoscopy (compact endoscopy) facilitates excellent therapeutic decisions during tumor surgery. Intraoperative determination of resection margins at an unprecedented precision is possible. In addition, assessment of the form and extent of the perpendicular vessel loops stimulated by epithelial signaling enables differential diagnostic decisions to be made, approximating our goal of an optical biopsy.


Laryngo-rhino-otologie | 2015

Evaluation eines Klassifikationsmodells horizontaler Gefäßveränderungen der Stimmlippen

A. Schossee; Susanne Voigt-Zimmermann; Siegfried Kropf; C. Arens

OBJECTIVEnThere exists no valid classification of beginning vascular changes of the vocal folds. We tested an own classification model of visible beginning horizontal vascular changes.nnnMATERIAL AND METHODSn168 indirect endoscopic pictures (84 white light=WL and 84 Narrow Band Imaging=NBI) of vocal folds were presented to 3 different consultants for classification (graduation normal, slight, moderately, high-grade belonged to the vascular features ectasia, meander, convolute, frequency of the vessels, ramification, change in direction). The self-confidence was declared by the consultants with a numeric rating scale.nnnRESULTSnA classification of beginning vascular changes of the vocal folds is possible, especially of ectasia, meander, convolute, frequency of the vessels, ramification, change in direction (p<0.0001). Significantly more vascular lesions can be detected by NBI than with white light endoscopy alone (p<0.0001). There are no significant differences (p=0.3529) in self-confidence of the classification. But it differs between the consultants highly significant (p<0.0001). The inexperienced classifier shows the highest growth in the learning curve. The intrarater- and interrater-variability differs only slightly between WL and NBI.nnnCONCLUSIONSnBeginning horizontal changes of vocal fold vessels can be classified. Endoscopic NBI-pictures of the vocal folds demonstrate the beginning of vascular changes better compared to endoscopic white light pictures alone. The familiarity and expertise with the classification model and the endoscopic imaging technique affect the self-confidence of the evaluation.

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Susanne Voigt-Zimmermann

Otto-von-Guericke University Magdeburg

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Michael Friebe

Otto-von-Guericke University Magdeburg

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Rudolf Hagen

University of Würzburg

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Ulrich Vorwerk

Otto-von-Guericke University Magdeburg

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