PubMed Health⌕ Search

Biomedical subjects

M Westhofen

Publications and source records attributed to M Westhofen.

At least 19 recordsLinked to original sources
PubMed2007

Relationship between matrix metalloproteinases MMP-2, MMP-9, tissue inhibitor of matrix metalloproteinases-1 and IL-5, IL-8 in nasal polyps.

BACKGROUND: Nasal polyps (NP), a subgroup of chronic rhinosinusitis, are characterized by interleukin 5 (IL-5) mediated infiltration of eosinophils in sinus mucosa, leading to pseudostratified ciliated columnar epithelium, thickening of the epithelial basement membrane and tissue edema. Matrix metalloproteinases (MMP) constitute a large group of Zn2+ dependent endopeptidases with the ability to degrade extracellular matrix and are possibly responsible for the development of tissue edema in chronic sinusitis. OBJECTIVE: The aim of this study was to determine the expression of MMP-2, MMP-9 and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) mRNA and to locate the distribution of MMP-2, MMP-9 and TIMP-1 by immunohistochemistry in ethmoid sinus mucosa in NP. Furthermore the correlation between IL-5 or IL-8 and MMP-2, MMP-9 or TIMP-1 is examined. METHODS: Nasal polyps of 33 patients and 18 specimens of inferior turbinate mucosa were examined by real time RT-PCR for MMP-2, MMP-9, TIMP-1, IL-5 and IL-8 mRNA expression. Immunohistochemical labeling for MMP-2, MMP-9 and TIMP-1 was performed. RESULTS: Differences between both locations were detectable for MMP-9 (P < 0.001) and IL-5 (P=0.003) but not for MMP-2 (P=0.278), TIMP-1 (P=0.515) and IL-8 (P=0.386). Correlation was detected only between TIMP-1 and IL-5 (r=0.422, P =0.014). Cytoplasmic staining of MMP-2 was present in the apical part of the ciliated cells, submucosal glands and in smooth muscle cells. Matrix metalloproteinase-9 was expressed in surface epithelium, in seromucous glands and in polymorphonuclear cells. CONCLUSIONS: Expression of MMP-9 and IL-5 mRNA are associated with NP. The correlation between IL-5 and TIMP-1 indicates the role of TIMP-1 in maintaining the homeostasis in NP.

Adult↗
PubMed2006

[Bilateral tumor of the nasal vestibule--a case report].

The authors report a case of a bilateral tumor of the nasal vestibule with a six-year history of progressive impairment of nasal breathing. After microsurgical transnasal excision, the finding was diagnosed as bilateral nasolabial cyst.

Aged↗
PubMed2006

[Endoscopic examinations of the eustachian tube].

BACKGROUND AND OBJECTIVE: Endoscopy of the eustachian tube allows direct examination of endoluminal alterations in the course of the organ. The aim of this study was to describe anatomic and functional findings in healthy awake subjects. PATIENTS/METHODS: Ten eustachian tubes in six healthy individuals with no history of tube dysfunction were examined under local anesthesia using different types of rigid and flexible endoscopes. RESULTS: Nine of ten tubes presented with no pathologic finding. The motility of the tube cartilage could be visualized in all cases and showed a wide variety. Prior anesthesia of the mucosa with the subject in the supine position, if necessary supplemented by a tube catheter, rendered the procedure more comfortable. CONCLUSION: The eustachian tube shows a wide spectrum of anatomic and functional varieties in normal subjects. The method allows comprehensive evaluation of anatomic and functional stenoses of the eustachian tube. The transnasal-transpharyngeal approach allows only limited evaluation of the middle ear structures.

Endoscopes↗
PubMed2005

[Main symptom otorrhea: diagnosis and therapy].

Otorrhea is an ambiguous symptom that underlies diverse clinical pictures. Fundamentally, the treatment of uncomplicated acute otitis externa and media can be carried out by the family physician. An ENT specialist should be definitely consulted in cases of complications or development of a chronic condition.

Adult↗
PubMed2005

[Infectious mononucleosis].

The primary infection with Epstein-Barr virus in an immunocompetent individual leads to infectious mononucleosis with symptoms of diphtheroid angina, lymph node swelling in the neck and hepatosplenomegaly. The most common age of infection lies between 15 and 25 years. The illness can affect a number of organs simultaneously and thus requires interdisciplinary diagnostics. For differential diagnosis, a differential blood analysis and a EBV quick test are required. The presence of IgM antibodies demonstrates the presence of the infection. Ultrasound of the abdomen can be made to determine the involvement of additional organs. In most cases, recovery occurs without complications. Acute cases can usually be handled successfully with medication. If symptomatic treatment fails, pharyngeal airway obstruction is possible and a tonsillectomy may be necessary. Otherwise, surgical treatment is obsolete. Generally, the prognosis is good. Severe courses and complications are rare.

Humans↗
PubMed2005

[Towards a cellular pathophysiology of Meniere's disease].

BACKGROUND: A modest increase in the hydrostatic pressure within the endolymphatic space may induce an endolymphatic hydrops which in turn is typically associated with Meniere's disease. However, there is no convincing pathophysiological model that might explain, on a cellular level, how a pressure increases may cause disturbed functions of vestibular hair cells and vertigo attacks. METHODS: So far, models involve osmotic mechanisms leading to electrolyte imbalances in the endolymphatic space. Alternatively, impaired longitudinal flow in the endolymphatic space is considered important. RESULTS: Recently, a pressure-sensitive potassium current was identified and characterized in vestibular hair cells. CONCLUSIONS: This current may modify the frequency behavior of a cell and may be the "missing link" in a cellular pathophysiology of the hydrops. Ion currents in hair cells offer attractive targets for pharmacological interventions in Meniere's disease.

Calcium↗
PubMed2005

[Time-dependent vestibular function loss of semicircular canals and otolith organs in Menière's disease].

INTRODUCTION: Since Dohlmann's investigations the extremely variable interindividual natural course of Menière's disease has been documented. The description of sub-entities of Menière's disease shows, the localisation of dysfunction within the labyrinth is of considerable importance. The selective investigation of crista and macula sensor organs and its time-dependent progression even provides information for the disease's staging. METHODS: In the retrospective trial presented here, 126 patients suffering from vertigo were tested by the methods described above. 10 of these patients who showed a triad of symptoms including vertigo attacks, unilateral sudden hearing loss and tinnitus were selected for this study. All 10 patients were tested within 48 hours after the last acute vertigo attack by means of caloric irrigation and VEMPs. RESULTS: The function loss verified in saccular testing could be found in Menière's disease progression at an earlier stage than the utricular function loss. Most patients with a long history of vertigo attacks also suffered from a dysfunction of the semicircular canals. DISCUSSION: The differential testing of the otolith function is a valid tool for the recognition of early labyrinth dysfunction in Menière's disease and could lead to an earlier onset of specific therapy. It also provides the base for a differentiated staging prior to therapy planning.

Adolescent↗
PubMed2005

[Otolith function tests--a differentiated, quality-assured screening system].

INTRODUCTION: More than 30% of all otogenic vestibular disorders are related to isolated macular dysfunction. Videooculographic examination techniques for the otolith-ocular reflex, e. g. by means of eccentric rotation tests, are not widely used in clinical routine as these put a considerable strain on technical and staff resources. Thus, there is a considerable risk of "false negative" classification of vertigo disorders being labelled as "non-otogenic". By means of vestibular-evoked myogenic potentials (VEMPs) and caloric irrigation in prone and supine position, several examination techniques for a side-related investigation of macula-induced vestibulo-ocular reflexes are available. The objective of this study is to compare and evaluate these techniques as screening tests. METHODS: In 32 patients with vestibular disorders we performed investigations for VEMPs, eccentric rotation tests, as well as caloric irrigation for macular reaction in prone and supine position. In addition, we performed other audiologic and vestibular function tests which were complemented by the clinical course in order to differentiate each case between otogenic and non-otogenic vertigo with or without macular affection. RESULTS: The technical feasibility as well as patients' acceptance for VEMP testing is better than for eccentric rotation tests. The sensitivity index for VEMPs (89%) as well as for caloric irrigation in prone and supine position for macular examination (71%) is satisfactory. However, the specificity of VEMPs is inferior (53%) to eccentric rotation (100%). DISCUSSION: Both the examination for VEMPs as well as caloric macular testing in prone and supine position carry features which make them feasible for screening, even though these two procedures test for two different parts of the otolith system. However, to confirm a diagnosis and to set up a therapeutic concept for macular function disorders, eccentric rotation should be added.

Caloric Tests↗
PubMed2004

[Function tests for the Eustachian tube. Current knowledge].

The Eustachian tube regulates the homeostasis of the middle ear. Problems with its function are predominantly found in childhood. As a consequence, otitis and hearing impairment occur. The most important muscle is the tensor tympani muscle. The complexity of the functional anatomy and physiology are reasons why no function test alone is capable of fulfilling all diagnostic needs. The predictive value of the various Eustachian tube function tests for the outcome of a tympanoplasty is not yet clear. An overview of clinically and scientifically relevant tests for the Eustachian tube function is provided.

Eustachian Tube↗
PubMed2004

[Cochlear reimplantation - experiences and results].

BACKGROUND: There have been remarkable developments in Cochlear Implants in the past years. Technical improvements lead to more reliable and durable devices. In cases of traumatic and atraumatic device failure a reimplantation of the Cochlear Implant is necessary. METHODS: In a retrospective study we examined 15 patients with 17 Cochlear reimplantation procedures after a traumatic or atraumatic device failure between 1996 and 2002. The reasons leading to the revision, the intraoperative findings, the perioperative complications and the postoperative audiological results as well as the personal evaluation of the revision procedure were analyzed. RESULTS: In our study there were 11 children and 4 adults. In 10 cases a traumatic and in 7 cases an atraumatic device failure lead to the reimplantation. In 13 of the 15 patients the revision surgery took place within 1 month after the date of device failure. The electrode array could be reinserted safely without any perioperative complications. The postoperative results showed a continuous development of speech perception in all patients. The personal evaluation of the reimplantation procedure was positive in all cases. CONCLUSIONS: Cochlear reimplantation in cases of traumatic or atraumatic device failure is a safe procedure without any serious perioperative complications. The timely reimplantation leads to a continuous development of speech perception.

Age Factors↗
PubMed2004

[Conservative treatment in mild obstructive sleep apnea: comparison of theophylline and nasal continous positive airway pressure ventilation].

BACKGROUND: Comparison of theophylline and nasal continous positive airway pressure-ventilation (nCPAP) in patients non eligible for surgical treatment with obstructive sleep apnea. PATIENTS AND MATERIALS: In a prospective non-randomized study 60 patients with mild obstructive sleep apnea were investigated. All individuals were not eligible for surgery under general anaesthesia or refused surgical treatment. The efficacy of a daily single dose oral theophylline (5 - 7 mg/kg body weight, n = 30) and nCPAP ventilation (n = 30) was evaluated by apnea-hypopnea index (AHI) and Epworth Sleepiness Scale (ESS). Statistical data analysis was performed using the Wilcoxon-Test. RESULTS: In the theophylline group 4/26 patients (15 %) showed a mean AHI reduction of 42 %. The ESS-Score improved from 10.0 to 8.0. Therapy compliance was 86 %. The non-responder (22/26 patients, 85 %) group showed a mean AHI increase of 11 % (from 24.6 to 27.3). This difference was not of statistical significance (p < or = 0.878). In the CPAP group the AHI decreased from 23.3 to 2.9 (p < or = 0,0001). Mean ventilation pressure was 6.4 mbar. The ESS-Score improved from 10 to 8. Compliance was 50 %. Six of thirty patients (20 %) did not use the CPAP device regularly. During the first four weeks another nine of thirty (30.7 %) patients turned back the device. Main reasons were discomfort (61 %), noise (38 %), rhinitis, conjunctivitis and discomfort of the partner (10 %). CONCLUSIONS: None of the treatments investigated can be considered as a substantial alternative for the majority of patients non eligible for surgery. Theophylline has a high compliance but little therapeutic effect. CPAP-ventilation is more effective but has a compliance problem in the patients investigated. Both modalities may have benefit but have to be individually indicated. A multimodal approach may ease the problem.

Administration, Oral↗
PubMed2003

Potassium currents in vestibular type II hair cells activated by hydrostatic pressure.

An elevated hydrostatic pressure in the endolymphatic space of the inner ear is discussed as pathophysiological factor in hydrops-related diseases of the inner ear. An increase in pressure by fractions of 1 cm H(2)O is sufficient to induce vertigo-like symptoms in animal models. To establish a link between hydrostatic pressure and the function of vestibular hair cells, we studied potassium currents in isolated vestibular type II hair cells from guinea-pig utricles when the hydrostatic pressure was increased by raising the height of the bath from 0.2-0.5, 0.7 or 1.0 cm. Elevated pressure enhanced K(+) currents significantly; a rise in pressure from 0.2-0.5 cm H(2)O increased the total K(+) current at +40 mV by 22+/-14% (+/-S.D.). The pressure-sensitive current I(K,p) was non-inactivating during depolarizing pulses. It was maintained when the pressure was kept elevated for several minutes and receded promptly after return to a pressure of 0.2 cm H(2)O. Voltage-gated Ca(2+) currents, in contrast, were not altered by hydrostatic pressure. A pharmacological characterization of I(K,p) revealed that tetraetylammonium (100 mM) abolished all outward currents including I(K,p). I(K,p) was partly and reversibly inhibited by 4-aminopyridine. Dihydrostreptomycin, a blocker of the transduction channel, left I(K,p) unaffected. Charybdotoxin (100 nM), a blocker of Ca(2+)-dependent K(+) channels, completely yet reversibly abolished I(K,p). We conclude that small elevations in hydrostatic pressure evoke a charybdotoxin-sensitive, probably Ca(2+)-dependent K(+) current in vestibular hair cells. This is likely to alter their frequency response and may be a relevant mechanism how hydrostatic pressure disturbs transduction.

Animals↗
PubMed2003

[Testing of the macula induced vestibuloocular reflex--possibilities and problems in the clinical routine].

INTRODUCTION: During the last years, an increasing number of papers is presented dealing with diseases and diagnostic procedures of the macula function. On the other hand, there are just a few distinct test setups for this purpose. In clinical routine, this kind of test system has to be efficient and effective to diagnostic and therapeutic findings. METHODS: The presented test setup includes examination of the semicircular canals by means of harmonic acceleration pendular rotation test and the bilateral, bithermal test as well as otolith function tests i. e. off vertical axis rotation (OVAR) and eccentric rotation. From March 1999 to May 2000 522 patients with dizziness were examined. RESULTS: Otolith tests results could be assessed in a range between 87 % to 95 % of the cases. The quality failure rate was significantly higher than in findings of semicircular canals examination procedures. The major caused technical problem were artifacts. Looking for the diagnostic relevance of the method, 37 % of the patients. Suffering from dizziness and who have normal findings in cupula VOR testing procedures revealed isolated macular dysfunctions. DISCUSSION: The relevance for diagnostic is demonstrated. Otolith function tests can be applied in clinical routine and give relevant information for diagnosis and treatment. Macula test procedures are still sophisticated. Technical development of VOG-recording is necessary for their general application in otology.

Acoustic Maculae↗
PubMed2003

[Electro-mechanic steering device for head-lamp mounted miniature video cameras].

BACKGROUND: Endoscopic or microscopic video recordings set a widely established standard for medico-legal documentation of operative procedures. In addition, they are an essential part of undergraduate as well as postgraduate medical education. Macroscopic operations in the head and neck can be recorded by miniaturised video cameras attached to the surgeon's head lamp. METHODS: The authors present an electro-mechanic steering device which has been designed to overcome the parallax error created with a head-mounted video camera, especially as the distance of the camera to the operative field varies. RESULTS: The device can be operated by the theatre staff, while the sterility of the operative field is maintained and the surgeon's physical working range remains unrestricted. As the video image is reliably centred to the operative field throughout the procedure, a better orientation and understanding for spectators who are unfamiliar with the surgical steps is obtained. CONCLUSIONS: While other adverse factors to macroscopic head-mounted video recordings, such as involuntary head movements of the surgeon, remain unchanged, the device adds to a higher quality of video documentation as it relieves the surgeon from adjusting the image field to the regions of interest. Additional benefit could be derived from an auto-focus feature or from image stabilising devices.

Endoscopy↗
PubMed2003

[Sonografic evaluation of oxygenation in head and neck cancer].

BACKGROUND: Tumor oxygenation is an important aspect of radiosensitivity. The authors describe a new method for a non-invasive assessment of tumor oxygenation in head and neck cancer. PATIENTS AND METHODS: A group of 20 patients with neck metastases of squamous cell cancer of the head and neck region was surveyed. At first a pO (2)-polarography was performed in the metastatic cervical nodes to investigate the tissue oxygenation. In a second step, the vascularisation of these nodes was visualised by color duplex sonography. In order to evaluate the extent of vascularisation in these nodes, the density of color pixels was quantified by a custom-made software program. The color pixel density and the pO (2) values were correlated and the statistic significance was calculated by Pearson's test. RESULTS: The mean vascularisation as evaluated by the means of color duplex sonography was 7.78 % [95 % CI 6.04 - 9.51]. The interindividual pO (2) values in the stroma of metastatic lymph nodes ranged between 9.0 and 27.4 mmHg (16.6 [95 % CI 14.06 - 19.13]). The mean values of pO (2)-fractions < 2.5/< 5.0/10 mm Hg were 32.25 %, 44.25 % and 53.29 % respectively. The median value of the pO (2)-fraction was 10.49 % [95 % CI 7.13 - 13.85]. The vascularisation as evaluated by color pixel density showed a statistically significant correlation with the pO (2)-fractions < 5.0 and < 10 mmHg (p < 0.045 and < 0.0001) and with the mean (p < 0.002) and median values of tissue pO (2) values (p < 0.0001) in polarography. CONCLUSION: The results in a limited number of patients suggest, that the proposed sonographic method allows a reliable non-invasive evaluation of tissue oxygenation in cervical metastases of squamous cell head and neck cancers.

Adult↗
PubMed2002

[Vestibular diagnostics in childhood - methods and assessment].

BACKGROUND: Children with vertigo are thought to be difficult to examine. Vestibular test batteries are used less frequently for children than in adult patients. METHODS: Within the context of a retrospective study 136 patients in age between 0 and 15 years, who were examined by Frenzel's glasses, ENG and VOG between 1996 and 1999 were evaluated. Caloric test and frequency selective rotation chair tests were performed. RESULTS: Workability of VOG examination (91 %) was higher than Frenzel glasses (86 %) and ENG (78 %). Videooculography is the method of choice in childhood. Comparing diagnosis after vestibular testing and discharge diagnosis a sensitivity of 68 %, a specificity of 88 %, an accuracy of aim of 79 % and a positive predictive value of 92,9 % was calculated. CONCLUSION: Thus restriction of vestibular functional diagnostics in childhood is not justified.

Adolescent↗