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C Pototschnig

Publications and source records attributed to C Pototschnig.

At least 19 recordsLinked to original sources
PubMed1999

Morphology of the human larynx during the first five years of life studied on whole organ serial sections.

The morphologic development of the human larynx during the first years of life is poorly understood to date. This study used plastinated whole organ serial sections to determine the growth and structure of the infant larynx. The larynges of 43 children 1 to 60 months old were plastinated. Whole organ serial sections were obtained by cutting the resulting specimen with a diamond band saw. The slices were then submitted to computer-assisted morphometric investigation. We found that the subglottic airway rapidly increases in size during the first 2 years of life. Further growth follows a linear mode. The relative proportion of the mucosal lining decreases likewise. In contrast to that in adults, and comparable to that in most mammals, the cartilaginous glottis accounts for 60% to 75% of the vocal folds' length at <2 years. No sexual dimorphism of the larynx exists during childhood. This study supplies detailed morphometric data on the growth and structure of the human larynx during the first years of life. It is the first to use plastinated whole organ serial sections for morphology of the pediatric larynx. Therefore, this study provides quantitative anatomic data of clinical interest that have not been available to date.

Child, Preschool↗
PubMed1998

[Voice quality after partial laser laryngectomy].

BACKGROUND: We conducted a prospective study to investigate voice quality after transoral endolaryngeal laser surgery in terms of ability to communicate effectively. Eighty patients with T1 or T2 glottic carcinoma were enrolled in the study. The main objective was to identify the influence of type and extent of surgery on postoperative voice parameters after endoscopic laser surgery. MATERIAL AND METHODS: The postoperative mechanism of phonation was assessed by videostroboscopy six months after surgery at the earliest. A phonetogram was produced and its area calculated (relative phonetogram, RP) in relation to a gender-specific normal phonetogram. A speech therapist (ST) and a trained otolaryngologist (TO) rated each voice independently for communication ability in a grade from 1 (poor) to 6 (near normal). RESULTS: After simple cordectomy the mean values were as follows: RP = 24.8%, TO = 3.26, ST = 3.33. When the anterior commissure was completely preserved mean results were better (RP = 34%, TO = 3.92, ST = 3.83). Results were worse following extended cordectomy (RP = 14.7%, TO = 2.82, ST = 3.00) and transglottic resection (RP = 13.7%, TO = 2.30, ST = 2.86), but similar within these two groups. The parameters RP, TO, and ST do not differ significantly between the group who had speech therapy after surgery (N = 33) and the group who did not (N = 47). Voice production at glottic level yields better results for every parameter than supraglottic substitute phonation. The amount of tissue removed was less significant. CONCLUSION: We conclude that postoperative phonatory results correlate with the postoperative mechanism of phonation. There is no linear correlation with the amount of tissue removed. Comparing similar types of resection preservation of the anterior commissure plays a key role. From the data in this study there is no evidence of a significant benefit from speech therapy. The parameter RP is an effective and relatively simple parameter to complete auditive voice assessment.

Endoscopy↗
PubMed1997

Electromyographic evaluation of vocal cord disorders.

In order to perform its basic functions, those of coordination of breathing, swallowing and speech, the larynx requires an intact neural apparatus to permit the perfect, well-coordinated action of the neuromuscular structures of extra- and intralaryngeal muscles. Electrophysiological measurements including electromyography, reflexmyography, electric and magnetic stimulated myography of the central motor nerve functions are the methods of classification of dysfunctions into neurapraxia, axonotmesis, neurotmesis, regeneration or myopathy. Different types of electrodes, depending on the methods of application, show a variety of neurophysiological findings which allow the investigator to decide about the type of lesion. An overview on neurophysiological techniques in vocal cord disorders is presented.

Axons↗
PubMed1997

[Virtual endoscopy with post-processing helical CT data sets].

PURPOSE: The purpose of this work was to test a newly developed, post-processing software for virtual CT endoscopic methods. Virtual endoscopic images were generated from helical CT data sets in the region of the shoulder joint (n = 2), the tracheobronchial system (n = 3), the nasal sinuses (n = 2), the colon (n = 2), and the common carotid artery n = 1). Software developed specifically for virtual endoscopy ("Navigator") was used which, after a previous threshold value selection, makes the reconstruction of internal body surfaces possible by an automatic segmentation process. We have evaluated the usage of the software, the reconstruction time for individual images and sequences of images as well as the quality of the reconstruction. All pathological findings of the virtual endoscopy were confirmed by surgery. RESULTS: The post-processing program is easy to use and provides virtual endoscopic images within 50 seconds. Depending of the extent of the data set, virtual tracheobronchoscopy as a cine loop sequence required about 15 minutes. Through use of the threshold value-dependent surface reconstruction the demands on the computer configuration are limited; however, this also created quality problems in image calculation as a consequence of the accompanying loss of data. CONCLUSIONS: The Navigator software enables the calculation of virtual endoscopic models with only moderate demands on the hardware.

Artifacts↗
PubMed1996

[Using a rotating suction debridement instrument with power generator in endonasal paranasal sinus surgery].

Endonasal nasal and sinus surgery using an endoscope for visual control has minimized the risks of surgery. A new technique is presented in which a suction-irrigation endoscope is used for visual control during surgery. The instrument is combined with a suction-rotation microdebrider with different tips and a power generator. The handling of this instrument is easy and atraumatic and it achieves a relatively bloodless field to reduce further the risk of inadvertent penetration of the skull base and lamina papyracea during endoscopic surgery.

Debridement↗
PubMed1995

Transoral laser resection with staged discontinuous neck dissection for oral cavity and oropharynx squamous cell carcinoma.

Transoral laser resection of oral cavity and oropharynx squamous cell carcinoma (OOSCC) is a widely accepted approach in the absence of cervical lymph node metastases. This study investigated the results of transoral laser surgery and discontinuous neck dissection (ND) for OOSCC with clinically obvious or suspected cervical node metastases. One hundred seventeen patients with infiltrating oral carcinoma were treated for cure with transoral resection of the primary and staged ND. Twenty-nine primaries were classified as T1, 50 as T2, 35 as T3, and 3 as T4. Lymph node metastases were identified in the ND specimen of 36 patients. All patients were followed for a minimum of 3 years unless they died. Estimated tumor-related survival after 5 years is 81% for stage I and II disease of the oral cavity, 86% for stage I and II disease of the oropharynx, 73% for stage III disease of the oral cavity, 65% for stage III disease of the oropharynx, and 21% for stage IV disease of the oral cavity and the oropharynx. Local and regional control of cancer was achieved in 72 (62%) of the 117 patients. Forty-five local and regional recurrences were diagnosed during the follow-up period. Two patients died of distant metastases with no evidence of local or regional recurrence. The combination of transoral laser resection and staged ND for the treatment of OOSCC seems to offer satisfactory cure rates for a selected group of patients. These two minor surgical interventions cause less morbidity than commando-type surgery and lead to low perioperative mortality and morbidity.

Adult↗
PubMed1995

Complete sphenoethmoidectomy and computer-assisted surgery.

Many surgical procedures in the field of ENT take place in close proximity to vital structures like the orbit, the skull base, the internal carotid artery etc. In our clinic we have decided to study two different computer-assisted navigation systems to reduce the risk of trauma to these structures during endonasal endoscopic procedures. Such systems should be able to correlate the position of the surgical instrument, ideally in the submillimeter range, to CT- or MR-images. The ARTMA Virtual Patient finds the position of the instrument by permanently measuring magnetic fields. The ISG-system uses a mechanical arm to localize the probe in the patient. Using Computer-Assisted-Surgery (CAS) does not significantly extend the time needed for surgery. We found that it prevents the surgeon from inadvertently injuring structures. Other groups have shown (1) that CAS-systems minimize the risk of complications of surgical procedures in the frontobasis arising from mishaps in the usage of the endoscope or the surgical tool. If properly used, CAS-systems can be a very helpful tool in the hand of an experienced surgeon but will never replace his expertise and knowledge.

Ethmoid Sinus↗
PubMed1994

Treatment of dysfunction of the cricopharyngeal muscle with botulinum A toxin: introduction of a new, noninvasive method.

Botulinum toxin is known as a relatively safe and efficacious agent for the treatment of various neurologic and ophthalmologic disorders. Since dysphagia and deglutition problems combined with aspiration are often caused by spasticity, hypertonus, or delayed relaxation of the upper esophageal sphincter (UES), conventional treatment including lateral cricopharyngotomy was replaced by localized injections of botulinum toxin into the cricopharyngeal muscle (CM) in a series of 7 patients. The study comprised patients with slight dysphagia caused by isolated hypertonus of the UES, as well as patients with severe deglutition disorders, complete inability to swallow, and aspiration problems. Preoperative diagnostic evaluation included careful history-taking, physical examination, cineradiography, and esophageal manometry to exclude other causes of dysphagia. For precise localization, injections were performed under general anesthesia after location of the CM by direct esophagoscopy and electromyographic guidance. Injections were administered into the dorsomedial part and on both sides into the ventrolateral parts of the muscle. Depending on the severity of symptoms and the intraluminal pressure of the UES, the dose varied between 80 and 120 units (botulinum toxin A from Dysport). The treatment outcome was evaluated by a disability rating score: patients' complaints were scored by subjective and objective parameters before and after injection. All but 2 patients experienced complete relief or marked improvement of their complaints. There were no severe side effects or postoperative complications. Local botulinum toxin injection proved to be an effective alternative treatment to invasive procedures for patients with isolated dysfunction of the UES, and also for patients with more complex deglutition problems combined with aspiration.

Adult↗
PubMed1992

Electrophysiologic investigation of lower cranial nerve diseases by means of magnetically stimulated neuromyography of the larynx.

Zoom endoscopic electromyography of the larynx, as introduced in 1979, has contributed greatly to the diagnosis of lower cranial nerve palsies, but in the early stage of a vagus nerve disorder one cannot investigate the nerve conduction from the brain stem to the laryngeal muscles with electrical stimulation. As with the early diagnosis of facial nerve palsies, up to now the intracranial part of the motoric brain nerves could not be stimulated directly. With a new magnetic coil device (Novametrix, Magstim 200) this intracranial stimulation is easily possible in the awake patient with painless magnetic stimuli that induce a muscle action potential into the laryngeal muscles. Hence, an immediate diagnosis is possible. Two coils with mean diameters of 8.5 or 3 cm were used. The stimulator delivered current pulses of peak amplitude up to 5,000 A with rise times of 140 microseconds and 65 microseconds, respectively, that generated peak fields of up to 2 T. In a healthy population, cisternal stimulation of the vagus nerve leads to a muscular response in the vocal muscle after 4 to 6.6 milliseconds (mean 5 milliseconds). Cortical stimulation leads to such a response after 9.5 to 12 milliseconds. Potentials in healthy individuals have been shown to be very uniform. Stimulation in recurrent nerve palsies may show prolongation of these latencies up to 30 milliseconds. The method is limited by the fact that complete neural blocks cannot be overcome by proximal stimulation. We have applied magnetic stimulation to 190 patients with different disorders of the vagus nerve.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1988

[Automated assessment of cranial nerve paralyses using computerized electromyography].

Until the formulae of Lindstrom et al. the automatic analysis of electromyograms had no empirical basis in the differentiation of neurapraxia and degenerative paralysis. The EMG-analysis computer program modified by Berg et al. was used for the evaluation of average power spectra derived with a Fast Fourier transformation on 37 patients with known neurapraxia and 54 with proven degeneration. In order to work out a characteristic function we calculated average power spectra separately for each type of paralysis (facial or laryngeal muscles). The resulting spectrum configurations and their absolute values (root-mean-square and central frequency) were compared, and their value in automated EMG analysis was analysed. The results provide a basis for the routine use of the computer program in routine clinical diagnosis.

Electromyography↗