Paul F. Schouwenburg
University of Amsterdam
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Featured researches published by Paul F. Schouwenburg.
Laryngoscope | 1998
Conrad F. Smit; Joep Tan; Pieter P. Devriese; Lisbeth M. H. Mathus-Vliegen; Marc Brandsen; Paul F. Schouwenburg
INTRODUCTION Gastroesophageal reflux may he relevant in the explanation of various otolaryngological symptoms.l-4 As yet, it is unclear whether gastric fluids need to reach the hypopharynx and travers, the upper esophageal sphincter (UES) in order to initiate symptoms. Nowadays, the best way to demonstrate gastroesophageal reflux is with ambulatory 24-hour dual-probe pH monitoring.526 Normal pH values for the distal esophagus have been extensively studied and are well established, in contrast to the pH values of the hypopharynx or proximal esophagus. Furthermore, there is no general agreement about the positioning and subsequent location of the proximal probe during monitoring. In this article we describe a new, easy, and reliable technique for the placement of the proximal probe without the use of manometry and the establishment of normal ranges for pH values a t the level of the UES.
Laryngoscope | 2000
Marcel P. Copper; Conrad F. Smit; Laki D. Stanojcic; Pieter P. Devriese; Paul F. Schouwenburg; Lisbeth M. H. Mathus-Vliegen
Objectives Laryngopharyngeal reflux may play a role in the etiology of squamous cell cancer of the head and neck and contribute to complications in head and neck cancer patients after surgery or during radiotherapy.
European Journal of Cancer | 2003
Joeri Buwalda; Paul F. Schouwenburg; Leo E. C. M. Blank; Johannes H. M. Merks; Marcel P. Copper; Simon D. Strackee; P.A. Voûte; H.N. Caron
The AMORE protocol is a local treatment regimen for head and neck rhabdomyosarcomas (HNRMS), consisting of Ablative surgery, Moulage technique brachytherapy and surgical Reconstruction. The aim of AMORE is to intensify local treatment for children with HNRMS and to avoid external beam radiation therapy (EBRT) and its long-term sequelae. All children with primary irresectable, non-orbital HNRMS in whom EBRT was indicated, were evaluated for the feasibility of AMORE. In 20 children, AMORE was performed (15 with parameningeal disease and five with non-parameningeal disease). Complete remission was achieved in all 20 patients. Local complications were limited. 5 patients experienced a local relapse and 1 patient developed distant metastases. Estimated 5-year OS and EFS were 67.5 and 64.1% for the entire group, and 64.2 and 60.0% for the parameningeal subgroup. We conclude that the AMORE protocol is a feasible strategy, with a good local control rate. Long-term sequelae of EBRT might be avoided although, to date, the follow-up is too short for definitive conclusions regarding these sequelae.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1998
Conrad F. Smit; Joep Tan; Lisbeth M. H. Mathus-Vliegen; Pieter P. Devriese; Marc Brandsen; Wilko Grolman; Paul F. Schouwenburg
Gastroesophageal reflux (GER) appears to be related to laryngeal carcinoma. Little is known about GER and gastropharyngeal reflux (GPR) in the laryngectomized patient. Therefore, GER and GPR were studied in laryngectomized patients.
Laryngoscope | 1999
Heidy A. J. Brok; Marcel P. Copper; Rutger J. Stroeve; Bram W. Ongerboer de Visser; Anjob J. Venker‐van Haagen; Paul F. Schouwenburg
Objective: To study the functional motor nerve supply of the upper esophageal sphincter in humans. Study Design: Intraoperative electromyographic study. Methods: The contribution of the recurrent laryngeal nerve and the pharyngeal plexus in the motor nerve innervation of the cricopharyngeal muscle and the inferior pharyngeal constrictor muscle was examined intraoperatively. Results: Electromyography showed that there is a considerable overlap in the innervation of the cricopharyngeal muscle and the inferior pharyngeal constrictor muscle. The recurrent laryngeal nerve functionally contributes to the motor innervation of the cricopharyngeal muscle in all patients and contributes to the motor innervation of the inferior pharyngeal constrictor muscle in most patients. The pharyngeal plexus functionally contributes to the motor innervation of the inferior pharyngeal constrictor muscle but does not always contribute to the motor innervation of the cricopharyngeal muscle. Conclusions: This is the first report which provides evidence that the recurrent laryngeal nerve functionally contributes to the motor innervation of the cricopharyngeal and inferior pharyngeal constrictor muscle. Furthermore, this study shows that intraoperative electromyography in humans is a feasible method to analyze the physiology of the motor innervation of the upper esophageal sphincter.
European Journal of Radiology | 1997
Charles B. L. M. Majoie; Frans-Jan H. Hulsmans; Bernard Verbeeten; Jonas A. Castelyns; Foppe Oldenburger; Paul F. Schouwenburg; D. Andries Bosch
OBJECTIVE To evaluate the magnetic resonance imaging (MRI) findings of 15 patients with perineural tumor extension along the trigeminal nerve in correlation with clinical data. METHODS The clinical records and MRI studies of 15 patients with perineural tumor extension along the trigeminal nerve were retrospectively reviewed. Imaging studies included plain and contrast-enhanced thin section T1-weighted spin echo (T1-WSE) MRI with and without fat-suppression. The studies were compared to determine which sequence provided greatest tumor conspicuity and best depiction of tumor extent. The conspicuity of these tumors was assessed on the available sequences by two observers by consensus. RESULTS The contrast-enhanced T1-weighted spin echo fat-suppressed images (T1-WSECEFS) demonstrated greatest tumor conspicuity and best depiction of tumor extent in the extracranial head and neck and skull base region. The conventional T1-weighted spin echo pre- and postcontrast images were, however, diagnostic of perineural tumor extension in 11 patients due to the presence of considerable tumor bulk and extension well above the skull base. In the other four patients the perineural tumor was poorly visualized on the conventional T1-WSE images and well visualized on the fat-suppressed images. The mandibular division of the trigeminal nerve (V3) was most commonly involved (n = 10), followed by the maxillary (V2; n = 5) and ophthalmic (V1; n = 2) division. Two patients had both mandibular as well as maxillary nerve involvement. The finding of perineural tumor extension had significant impact on patient management: based on the MR imaging study, the primary tumor was considered inoperable (n = 13), the extent of surgery was expanded (n = 2) and radiation therapy (RT) ports were extended (n = 12). CONCLUSION Complete trigeminal nerve imaging is recommended when evaluating (suspected) head and neck malignancies with a high risk for perineural extension. In these cases thin section axial and coronal precontrast T1-WSE MR images and postcontrast T1-WSE MR images with fat-suppression should be obtained. In the rare event that artifacts degrade the quality of the fat-suppressed images, contrast-enhanced T1-WSE sequences without fat-suppression can additionally be used.
Operations Research Letters | 1995
Wilko Grolman; Paul F. Schouwenburg; M.F. de Boer; Paul Knegt; H. A. A. Spoelstra; C.A. Meeuwis
The Blom-Singer adjustable tracheostoma valve (ATV) is a new tracheostoma valve, introduced in 1992 to improve voice rehabilitation after total laryngectomy. Little research has been done to evaluate the benefits of this valve. Our study evaluates the advantages and disadvantages of using this device. Eighteen laryngectomized patients with a low-resistance Provox voice prosthesis received an ATV, using minimal selection criteria. The patients are evaluated according to a specific protocol. The effectiveness of the humidifilter, valve and fixation method and the benefits are evaluated. Approximately 66% of the 18 patients are still using the ATV. We report the differences between the current users and the dropout group. Patient factors are discussed that seem to have an impact on the effective use of the valve, such as age and mucus production. We consider the ATV to be a valuable device for fingerless speech in the laryngectomized patient.
Laryngoscope | 1997
Wilko Grolman; Eric D. Blom; Richard D. Branson; Paul F. Schouwenburg; Ronald C. Hamaker
Bypassing the upper airway places the burden of humidification on the lower airway. For this reason passive heat and moisture exchangers (HMEs) are used in the laryngectomized patient in an attempt to minimize the effect of lost upper airway function. We measured efficiency and airflow resistance and calculated the costs of four HMEs used in the laryngectomized patient. The HMEs were measured according a modified International Standards Organization (ISO) 9360 standard. The airflow resistance was measured at flow rates of 15, 30, and 60 L/min. The measurements were repeated three times. Costs were calculated with two realistic scenarios. The study found that there are significant differences in moisture output and airflow resistance between the HMEs tested. There are major daily cost differences between these devices. This study shows that filter material and size influence the HMEs moisture output efficiency and airflow resistance considerably. The construction differences and filter and housing type have great influence on the HMEs daily costs. We believe that knowledge of the efficiency in combination with the average daily costs of the HMEs allows the clinician to make a balanced choice of which filter to use.
Operations Research Letters | 2007
Wilko Grolman; Simone E. J. Eerenstein; Frédérique M.L. Tan; Rinze A. Tange; Paul F. Schouwenburg
Background: In laryngectomized patients, tracheoesophageal voice generally provides a better voice quality than esophageal voice. Understanding the aerodynamics of voice production in patients with a voice prosthesis is important for optimizing prosthetic designs and successful voice rehabilitation. Objectives: To measure the aerodynamics and sound intensity in tracheoesophageal voice production. Study Design and Methods: We built a special setup, which consisted of a Pentium 200 MHz computer with an AD-DA interface card and Labview 4.01 software. In an oral/nasal mask we constructed several mass flow sensors and a microphone. This measured both the oral airflow and the level of sound. For the measurement of endotracheal pressure, which is the driving force behind the airflow, we used a transducer which was connected to the tracheostoma. The endoesophageal pressure was measured at the level of the prosthesis in the esophagus by a Mikrotip transducer. Using this we could determine how much the voice prosthesis contributes to the overall pressure drop of the phonatory tract. Furthermore, the average airflow rate as a function of the sound pressure levels could be determined. Results: In our population, 6 out of 7 patients showed a positive relationship between trans-source airflow and generated sound intensity. We compared our prosthesis pressure drop values with in vitro data and found that there are some differences, possibly due to difference in age of the prosthesis and physiological circumstances in vivo. The overall contribution of the voice prosthesis to the airway resistance depends on the level of phonation and the type of device. In our patient group it is apparent that the pharyngoesophageal (PE) segment has the greatest share of the total pressure drop, especially at higher airflow rates. We measured a 27% pressure drop in airflow over the voice prosthesis. Different tracheostoma occlusion methods did not have any effect on the aerodynamics and sound intensity. One patient that had had a jejunal graft for reconstruction showed, not unexpectedly, extremely different aerodynamic values. We were unable to define optimal airflow rates or optimal resistance values for sound production in the PE segment. Conclusion: The aerodynamic characteristics of voice production in laryngectomized patients with voice prostheses are determined by both prosthetic factors and PE segment tissue factors. In our patient group the PE segment is responsible for the greatest pressure drop. We found no significant difference in pressure drop and sound intensity for different tracheostoma occlusion methods.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2005
Joeri Buwalda; Nicole J. Freling; Leo E. C. M. Blank; Alfons J. M. Balm; Johannes Bras; Paul A. Voute; Huib N. Caron; Paul F. Schouwenburg; Johannes H. M. Merks
The AMORE protocol is a local treatment for patients with nonorbital pediatric head and neck rhabdomyosarcoma (HNRMS). The objectives of this study were: (1) to assess the adequacy of the concept, and (2) to identify factors associated with relapse.