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M Walz

Publications and source records attributed to M Walz.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Rupture of the azygos vein by blunt thoracic trauma. A case report and literature review].

Blunt chest trauma is a common injury in traffic accidents. Thoracic vessel trauma frequently affects intercostal arteries, the aorta and less often the subclavian artery. Azygos vein injury is uncommon and has previously been described in only 19 cases. The 20th case of blunt azygos vein injury due to high energy trauma as a consequence of a traffic accident is reported with a review of the literature. Preoperative diagnosis was performed by computed tomography. Azygos vein injury is rare but potentially lethal (8/20, 40.0%). Chest radiograph with right hemothorax is reported consistently except for two cases. Fractures of ribs and/or thoracic spine (T3-5) were found in nine patients, while neither were found in 11/20 cases. Pathognomonic signs have not been described in the literature. Early resuscitation and immediate thoracotomy with recognition and treatment of azygos vein rupture is necessary to avoid a fatal outcome.

Accidents, Traffic↗
PubMed2002

[Quality assurance with teleradiology].

Teleradiology offers many applications for quality assurance in medicine. The spectrum reaches from electronic consultations in emergency or special cases and double reading--along with new models of cooperative work and medical networks--to technical quality assurance and integration into interinstitutional and patient controlled health records. Regional teleradiology networks based on server concepts can fulfill the developing technical and organisational requirements. The increasing mobility arising from smaller radiological equipment and improved accessibility to experts with minimized visualisation and reporting systems will change the radiological world of tomorrow, especially in combination with the usage of knowledge based systems in reference data bases and computer assisted diagnosis (CAD). Teleradiology by itself must be liable to quality assurance measurements to prevent unnecessary radiation exposure or danger to the doctor patient relation.

Computer Communication Networks↗
PubMed2002

[The future of teleradiology: results of Teleradiology Expert Meeting of the Health Network Congress 2001].

Legal prerequisites have substantial influence on the development of teleradiology. At an expert meeting (Mannheim, 8.6.2001) a proposal for a teleradiology article in the new German x-ray ordinance has been set up. An exception of the demand for a doctor trained in radiation protection at the point of examination shall be established for emergency cases. To realize the intended improvement of patient care measurements for quality assurance concerning the medical personnel and processes are necessary. Along with other current developments the basis of secure regional teleradiology networks is now built up.

Forecasting↗
PubMed2002

Maturation of thyroidal dendritic cells in Graves' disease.

Because thyroidal dendritic cells (t-DC) may be implicated in the pathogenesis of Graves' disease (GD), we compared t-DC in thyroid sections of patients with GD (n = 15) and control patients with toxic (TG; n = 12) or non-toxic goitre (NG; n = 12). Goitres in GD, but not TG or NG, were populated with three discernible t-DC phenotypes. (i) Immature t-DC (major histocompatibility complex (MHC) II+/CD40-/CD80-) were located perifollicularly (95% of the patients with GD, but only 55% of TG and 51% of NG patients); numbers of such t-DC were significantly elevated in GD (P < 0.001). (ii) Partially matured CD80+ t-DC were present in connective tissue (73% of the patients) and focal interstitial clusters (40% of the patients). In 53% of the patients with GD, single as well as clustered interstitial t-DC expressed CD40. (iii) However, phenotypically mature t-DC (MHC II+/CD40+/CD80+/RFD1+) were only present in clusters and colocalized with activated CD4+/MHC class II+ T-helper (Th) cells. Expression of CD54 and CD83 did not significantly differ among the groups. The phenotype of intrathyroidal DC in GD thus supports their role as potential (co)stimulators of thyroid autoimmunity.

Adult↗
PubMed2002

A murine interleukin-4-Ig fusion protein regulates the expression of Th1- and Th2-specific cytokines in the pancreas of NOD mice.

Interleukin (IL)-4 is a key cytokine in T-helper type 2 (Th2) immune response. We have constructed a dimeric IL-4 molecule consisting of the murine IL-4 and the murine Fc part of IgG2a. We first tested the biological activity of the chimeric protein by in vitro studies using isolated murine spleen cells. IL-4-Ig was found to downregulate LPS-induced IFN-gamma and TNF-alpha production. The immunomodulatory potential of the fusion protein was also analyzed in non-obese diabetic (NOD) mice, an animal model for human type 1 diabetes. Female NOD mice aged 10 weeks were treated once with cyclophosphamide to accelerate and synchronize the progression of insulitis. Treatment with IL-4-Ig induced strong modulation of the pancreatic cytokine balance. Expression was downregulated for both Th1-specific cytokine IFN-gamma and the Th2-specific cytokine IL-10. IL-12p40 expression was only slightly affected. Interestingly, infiltration increased in the islets of IL-4-Ig-treated animals, and therefore did not correlate with the decreased IFN-gamma expression. Hence, IL-4-Ig did not prevent the progression from peri- to intra-insulitis, but suppressed inflammatory cytokine production. In most experiments, the biological activity of IL-4-Ig and IL-4 was comparable. We conclude that treatment with the chimeric protein IL-4-Ig effectively downregulates Th1 responses but simultaneously augments intra-islet infiltration.

Animals↗
PubMed2002

[New concepts in teleradiology with Dicom e-mail].

UNLABELLED: The recently published Dicom supplement 54 (dicom e-mail) defines a connection between the internet and the medical communication inside hospitals. Up to now vendor specific dicom protocol additions were needed to realize certain teleradiology solutions. The new concept relies on vendor independent standard protocols without specific additions. MAIN FEATURES: client-server solution using the internet designed for emergency medicine integration of various clinical informations approved security concept modularized architecture The concept was realized within the scope of a teleradiology project of the state of Rheinland-Pfalz, Germany. It will be expanded to the state of Baden-Wuerttemberg. Germany in 2002 with over 20 hospitals included.

Computer Systems↗
PubMed2000

3D norm data: the first step towards semiautomatic virtual craniofacial surgery.

When planning craniofacial surgical interventions, the ideal appearance of the patient is very important. The final appearance should be as close as possible to that which the patient would have if he/she were without defects. Our first step towards achieving this is to build a database containing sets of three-dimensional CT images that allows for comparison of the shape of a patient with defects to the typical shape of an age- and sex-matched "average" person without defects. We started to collect CT data from patients without pathologies and, in co-operation with two radiology institutes (in Mannheim and Heidelberg), over 100 CT data sets have now been collected and classified according to age and sex. It is necessary to choose an appropriate statistical method to calculate the norm data from the different data sets. Based on the statistical method, an age- and sex-matched "average" model of the anatomy will be created.

Adolescent↗
PubMed2000

[Does liberation of interleukin-12 correlate with the clinical course of polytraumatized patients?].

INTRODUCTION: Interleukin-12-p70 (IL-12-p70) is a potent immunoregulatory cytokine composed of a heavy chain (p40) and a light chain (p35). Contradicting results have been reported with regard to leukocyte release and systemic concentration of IL-12 after polytrauma. METHODS: We daily analyzed systemic concentrations of IL-12 in polytrauma patients (n = 37, mean ISS 33.9) in comparison to healthy donor values during intensive care course by ELISA. Patients were divided according to their mean IL-12 levels into those with elevated IL-12 (group 1, n = 7), those with decreased IL-12 (group 2, n = 4) and those with IL-12 in the normal range (group 3, n = 26). RESULTS: Patients in group 1 revealed elevated levels of IL-12 up to p70 > 1000 pg/ml and p40 > 2500 pg/ml. The common clinical feature of group 1 was a thorax trauma in combination with pneumonia (85% survivors). Patients with single thorax trauma or pneumonia without thorax trauma (group 3) showed normal IL-12 values. Patients with decreased IL-12 levels revealed also a thorax trauma and pneumonia but all patients succumbed. The groups significantly differ in their stay in the intensive care unit, in TISS, in MODS score and in respiratory ratio, but not in ISS, mean CRP values and leukocyte counts. Correlation analysis revealed no significant relation between systemically altered IL-12 values and clinical parameters, with the exception of a negative correlation of p70 and ISS (r = -0.785) or MODS score (r = -0.314) in group 1. CONCLUSIONS: After major injuries there is no overall suppression of IL-12 formation. Patients with normal or elevated IL-12 levels belong mainly to the survivors, whereas patients with decreased IL-12 levels are at high risk of succumbing to multi-organ failure.

Adolescent↗
PubMed2000

[Femoral neck fracture. Osteosynthesis or which endoprosthesis is indicated?].

Femoral neck fractures are frequent fractures of the elderly. They can be treated by the use of dynamic hip screws, lag screws, bipolar hemi-protheses or total hip replacement. The results are markedly influenced by the timing of the operation and the choice of the implant. Using the Garden classification of femoral neck fracture we demonstrate a different therapeutic approach according to Garden stadium I-IV.

Aged↗
PubMed2000

Teleradiology requirements and aims in Germany and Europe: status at the beginning of 2000.

Specific radiological requirements have to be considered for realization of telemedicine. In this article the goals and requirements for an extensive implementation of teleradiology are defined from the radiological user's point of view. Necessary medical, legal and professional prerequisites for teleradiology are presented. Superior requirements, such as data security and privacy or standardization of communication, must be realized. Application specific requirements, e. g. quality and extent of teleradiological functions as well as technological alternatives, are discussed. Each project must be carefully planned in relation to one's own needs, extent of functions and system selection. Topics like legal acceptance of electronic documentation, reimbursement of teleradiology and liability must be clarified in the future.

Europe↗
PubMed2000

Induction chemotherapy followed by concurrent chemotherapy and high-dose radiotherapy for locally advanced squamous cell carcinoma of the upper-thoracic and midthoracic esophagus.

The purpose of this study was to evaluate the efficacy and toxicity of an induction chemotherapy schedule followed by high-dose radiotherapy and concurrent chemotherapy for locally advanced squamous cell carcinomas of the upper and midthoracic esophagus. Patients were treated with three courses of fluorouracil, leucovorin, etoposide, and cisplatin-containing induction chemotherapy followed by high-dose external beam radiotherapy to 65 Gy in 6 weeks for T4 and obstructing T3 tumors. Transversable T3 tumors received 60 Gy in 6 weeks by external radiotherapy, followed by two high-dose-rate esophageal brachytherapy fractions of 4 Gy in 5-mm tissue depth. Concurrent to radiotherapy, cisplatin and etoposide were given. Long-term survival of 22 patients was 41% and 31% at 2 and 3 years, respectively, with a median follow-up of 39 months. The probability of locoregional tumor recurrence was 60% at 3 years for all patients and 30% for those with a partial or complete response to induction chemotherapy. Acute toxicity of this schedule was moderate. Long-term survivors had a good swallowing function. This schedule offers a considerable chance of long-term survival for patients with locally advanced squamous cell carcinomas of the upper and midthoracic esophagus. Local in-field recurrences are the main risk after definitive radiochemotherapy. Dose escalation of radiotherapy is possible because of the observed low late toxicity.

Adult↗
PubMed1999

[In Process Citation]

Mechanical ventilation is a well-established strategy in intensive care medicine. ICU trauma patients require analgesia, and sedation mostly consists of benzodiazepines and opioids with increasing doses over time. The weaning period is complicated by the withdrawal syndrome, showing tachycardia, hypertonia, tachypnea and restlessness. Although treatment with clonidine can influence these symptoms, tachypnea still remains the main problem in weaning patients from mechanical ventilation. Adding sufentanil, an opioid with greater effects on analgesia than on respiratory depression compared with fentanyl, tachypnea can be reduced to normal frequency. In this way weaning management can be managed more easily for the benefit of both, the patient and physician. In comparison with a group of 50 patients treated with clonidine alone, 72 patients treated with clonidine/sufentanil showed a shorter period from the start of spontaneous ventilation until extubation (4.8 vs 7.6 days) and until discharge from the ICU (7.7 vs 12.4 days). The number of reintubations caused by respiratory exhaustion decreased from 16.0 to 2.8%.

Journal Article↗
PubMed1999

[Transport-fixator for reconstructive surgery of the extensor apparatus of the knee joint].

Operative repair in ruptures of the extensor mechanism of the knee joint mostly requires additional external or internal fixation by plaster, transfer of tendons or encircling wires. Reconstruction of initially undiagnosed ruptures has to solve the problems of fixed proximal or distal migration of the patella and tendenous shortening. This can be performed with a tibiopatellar external fixator which allows gradually reduction of the patella in an anatomical position before operative reconstruction by suturing or reinsertion. During this period as well as a post-operative protection this fixator enables patients to maintain motion of the knee joint and full weightbearing. This technique can avoid poor functional results caused by long periods of immobilisation and is helpful in patients with marked displacement of the patella and inability to manually reduce the patella distally when delayed repair is necessitated.

Adult↗
PubMed1999

Dental print media and their value in forensic odontology.

Teeth are one of the most important factors in the identification of unknown cadavers. One of the most efficient methods the police have of publicizing a case is to publish the victim's dental x-rays of treatment records in the dental print media which dentists will often recognize and thus be able to contribute to the identification. To evaluate the efficiency of this procedure, 177 cases published between 1975 and 1995 were reviewed. The results show that only 3% of the cases were identified from recognition in the dental print media. A survey of 500 dentists was carried out to gauge the efficacy of the presentation of identification cases in their dental print media. According to these results a revised method of presentation needs to be developed to improve the efficiency of this odontoforensic publicity medium. New technologies could also open new avenues for forensic identification such as digital x-raying or online data transfer. The Internet itself could be useful regarding international cooperation of forensic odontologists in the identification of unknown corpses.

Dental Records↗
PubMed1999

Economic analysis of teleradiology applications with KAMEDIN.

The teleradiology system KAMEDIN (German Telekom), installed on HP-Unix- and NT-Workstations, was evaluated in different scenarios and a cost-benefit-analysis was performed. CT examinations were transferred from a PACS workstation (GE) to KAMEDIN using DICOM-3 protocol. Teleconferences were realized with an intensive care unit by LAN, with a radiology department at 5 km. distance by ISDN, and with an on duty radiologist 22 km. away by ISDN. On average, 36 CT slices per patient were transferred. Overall costs (costs for hardware, software, support, ISDN-fees, and staff) were compared to possible cost reduction, mainly concerning transportation and films. These three scenarios could be realized during daily routine work. Differing in their amount of transportation cost reduction, two applications (intensive care unit, radiologist on duty) showed a break-even at 1817, respectively 528 teleconferences/year. Improvement of cost-effectiveness can be obtained on the conditions that existing hardware will be used and that the automatic data transfer will be improved. Combining all optimisation factors, the break-even decreased to a minimum of 167, respectively 77 teleconferences/year. The optimisation of patient management is an additional--but in this study, not yet counted--advantage of teleradiology.

Computer Communication Networks↗