Background and study aims: Endoscopic Vacuum Therapy (EVT) has been reported as a novel treatment option for esophageal leakage. We present our results in the treatment of iatrogenic perforation with EVT in a case series of 10 patients. Patients and methods: An open pore polyurethane drainage was placed either intracavitary through the perforation defect or intraluminal covering the defect zone. Application of vacuum suction with an electronic device (continuous negative pressure, –125 mmHg) resulted in defect closure and internal drainage. Results: Esophageal perforations were located from the cricopharyngeus (4/10) to the esophagogastric junction (2/10). EVT was feasible in all patients. Eight patients were treated with intraluminal EVT, one with intracavitary EVT, and one with both types of treatments. All perforations (100 %) were healed in within a median of (3 – 7) days. No stenosis occurred, no complications were observed, and no additional operative treatment was necessary. Conclusions: Our study suggests that intraluminal EVT will play an important role in endoscopic management of esophageal perforation.

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Closed circuit steam cooling of blades and vanes in modern gas turbines is an promising alternative instead of film-cooling using compressor air. The temperature drop across the first-stage nozzle, which is convectively steam-cooled, is reduced significantly in comparison to an intensive film-cooled vane using compressor air. Thus, the firing temperature (temperature in front of the first-stage blade row) can be increased while the combustion temperature can remain as low as necessary for low-Nox purpose. In this paper, a steam-cooled test configuration consisting of a 3-vane cascade is numerically analysed. A computer code using a Conjugate Calculation Technique is applied. The CHTflow code has been developed at the Institute of Steam and Gas Turbines in Aachen. Due to the direct coupling of fluid flow and solid body, heat transfer boundary conditions at the external and internal surfaces become unnecessary. Validation of the code for a similar convection-cooled configuration is also given here. The presented investigations focus on the thermal load analysis and the cooling efficiency analysis of the test configuration. It consists of a planar cascade with a convection-cooled central vane where cooling fluid can be supplied to 22 radial passages. One main aspect of the paper is to show the influence of cooling steam conditions (low-, medium & high-pressure steam supply) on the local and global cooling efficiencies. The results show that, for reaching a defined cooling efficiency level, medium steam pressure supply might be advantageous in comparison to a high-pressure level in supply. Although a lower pressure level demands an increase in steam mass flow, the overall effect on the thermal efficiency of the whole process is acceptable if one keeps in mind the advantages of handling steam at lower pressure levels. For further comparison, convective air-cooling with reasonable cooling conditions and comparable flow and heat transfer characteristics is analysed. For the given geometry of the configuration, sufficient cooling of the trailing edge becomes problematic for steam- and air-cooling application.

BackgroundIn recent years, intra arterial chemotherapy has become an important component in head and neck cancer treatment. However, therapy success can vary significantly and consistent treatment guidelines are missing. The purpose of this study was to create a computer simulation of the chemical agent injection in the head and neck arteries to investigate the distribution and concentration of the chemical.MethodsRealistic three dimensional patient specific geometry was created from image scan data. Pulsatile blood flow, turbulence, the chemical agent injection via a catheter, and the mixture between blood and the chemical were then simulated through the arterial network by computational fluid dynamics software.ResultsThe results show a consistent chemical distribution throughout all the arteries and this is ineffective. In addition, due to high wall shear stress and turbulence at the inner bifurcation wall, serious complications during the treatment could occur, for instance haemolysis or thrombosis.ConclusionsThe modelled catheter position is insufficient to provide a high chemical agent concentration in the desired tumour feeding artery, which is vital for therapy success.

focused on patients with RSA in view of range of motion, strength, Constant score and a standardized questionnaire. Methods PatientsTwenty three patients at the age of 52-90 years who were operated due to proximal humerus fractures from September 2011 to February 2017 were included in this retrospective study. All patients were provided with a DELTA XTEND prosthesis (DePuy Synthes). Indications for RSA were an extended rotator cuff defect and fracture displacement. An extended rotator cuff defect was defined as tears ≥5 cm or defects with two or more tendons involved. 5 Rotator cuff defects were diagnosed by magnetic resonance imaging (MRI).Patients with severe neurologic, cardiac or pulmonal comorbidities were excluded. All patients gave written informed consent to participate in the study. Ethics approval was obtained from the local ethics committee (No. D463/16). DELTA XTEND prosthesis (DePuy Synthes)The DELTA XTEND prosthesis is a total semi-constrained shoulder arthroplasty. The scapula-humeral joint center of rotation is moved medially and inferiorly, which increases the deltoid lever arm and deltoid tension.Therefore the deltoid muscle can compensate for impaired rotator