Precise Placement (precise + placement)

Distribution by Scientific Domains


Selected Abstracts


A Late Carboniferous fossil scorpion from the Piesberg, near Osnabrück, Germany

FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2008
Jason A. Dunlop
Abstract A new fossil scorpion , only the second from the Late Carboniferous (Pennsylvanian) of western Germany , is described from the Westphalian D of the Piesberg near Osnabrück, Germany. This slender and rather gracile specimen is very closely related to the stratigraphically contemporary Eoscorpius carbonarius Meek & Worthern, 1868 from Mazon Creek, Illinois, USA and is here assigned to E. cf. carbonarius. A precise placement is hindered by the need for revision of the late Carboniferous scorpion fauna. (İ 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


A New Stent Design for the Treatment of True Bifurcation Lesions: H-Side Branch Stents

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2010
MYEONG-KI HONG M.D.
Background:There has been much debate for the adequate treatment strategies for true bifurcation lesions. The purpose of this study is to introduce and test a novel stent design for the treatment of true bifurcation lesions. Methods:This side branch stent is composed of three parts: proximal, connecting, and distal parts. The distal part for the side branch vessel has a slope-side stent margin for circumferential coverage of the ostium and one radio-opaque marker for targeting the carina. The proximal part with two radio-opaque markers operates for safe stent delivery and useful guidance for a more precise placement of the distal part on the side branch ostium. Results of the in vitro test in the acrylic resin-made bifurcation phantom model were evaluated with microcomputer tomography. Animal experiments with this new stent platform were also performed in five pigs. Results:In vitro test and microcomputer tomography showed complete coverage of the side branch ostium circumferentially with stent struts, and the absence of stent struts in the main vessel above the side branch ostium level. This side branch stents were successfully deployed in all 5 pigs. The results of animal experiments were also similar to those of in vitro tests. Conclusions:In vivo and vitro tests demonstrated the effective modality of this side branch stent for the treatment of true bifurcation lesions. (J Interven Cardiol 2010;23:54,59) [source]


A robotic assistant for stereotactic neurosurgery on small animals

THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 4 2008
L. Ramrath
Abstract Background This work presents the development and performance analysis of a robotic system for stereotactic neurosurgery on small animals. The system is dedicated to the precise placement of probes in the small animal brain, thus providing an improved framework for brain research. Methods Based on an analysis of small animal stereotaxy, the mechanical design of the robotic system is presented. Details of the structure and mechanical components and a kinematic description are outlined. The calibration process of the system for arbitrary probes is described. To analyse the mechanical positioning accuracy of the system, a testbed is presented. Results Positioning performance results show that the system features a mean mechanical positioning accuracy of 32 µm and a mean positioning repeatability of 11 µm. Conclusion The system meets the requirements of targeting small functional areas within the brain of small animals and thus offers a new tool for small animal brain research. Copyright İ 2008 John Wiley & Sons, Ltd. [source]


Suspension Laryngoscopy for Endotracheal Stenting,

THE LARYNGOSCOPE, Issue 1 2003
Hans Edmund Eckel MD
Abstract Objectives/Hypothesis Airway stents have recently been used to establish and maintain patent airways in patients with malignant central airway obstruction, but insertion modalities remain controversial to date. The study seeks to determine the role of suspension laryngoscopy in interdisciplinary airway stenting. Study Design Retrospective, single-institution analysis of a case series treated by a multidisciplinary airway team. Methods Ninety-three consecutive patients with malignant obstruction of the trachea and/or tracheobronchial bifurcation underwent endotracheal stenting through a suspension laryngoscopy approach for the relief of impending respiratory distress. Feasibility, mortality, survival, and complications were analyzed as main outcome measures. Results Stenting through a suspension laryngoscopy approach was feasible 91 of 93 patients (97.8%). Fifteen patients needed repeated stenting, and in all, 121 stents were implanted during the observation period. This approach allowed for the repeated insertion of rigid bronchoscopes of graded sizes to establish an airway and for precise stent positioning. Optical instruments and stent introducer systems could easily be used while adequate ventilation was continuously maintained. Silicone stents of maximal size were inserted without injury of the vocal cords during intubation. Median survival for all patients was 8 months. No intraoperative airway complications were observed, and no patient died secondary to stenting. Conclusions Suspension laryngoscopy and jet ventilation provide an ideal setting for the precise placement of tracheal and bifurcation airway stents. Laryngologists should actively participate in interdisciplinary airway stenting programs. [source]