bluuebunny/crossref_metadata_2025_split huggingface dataset:
Derivation of the respiratory rate from directly and indirectly measured respiratory signals using autocorrelation
Authors: Schrumpf Fabian , Sturm Matthias , Bausch Gerold , Fuchs Mirco 
Published: December 2016

Abstract
The estimation of respiratory rates from contineous respiratory signals is commonly done using either fourier transformation or the zero-crossing method. This paper introduces another method which is based on the autocorrelation function of the respiratory signal. The respiratory signals can be measured either directly using a flow sensor or chest strap or indirectly on the basis of the electrocardiogram (ECG). We compare our method against other established methods on the basis of real-world ECG signals and use a respiration-based breathing frequency as a reference. Our method achieved the best agreement between respiration rates derived from directly and indirectly measured respiratory signals.
Real-time QRS detection using integrated variance for ECG gated cardiac MRI
Authors: Schmidt Marcus , Krug Johannes W. , Rose Georg 
Published: December 2016

Abstract
During magnetic resonance imaging (MRI), a patient’s vital signs are required for different purposes. In cardiac MRI (CMR), an electrocardiogram (ECG) of the patient is required for triggering the image acquisition process. However, a reliable QRS detection of an ECG signal acquired inside an MRI scanner is a challenging task due to the magnetohydrodynamic (MHD) effect which interferes with the ECG. The aim of this work was to develop a reliable QRS detector usable inside the MRI which also fulfills the standards for medical devices (IEC 60601-2-27). Therefore, a novel real-time QRS detector based on integrated variance measurements is presented. The algorithm was trained on ANSI/AAMI EC13 test waveforms and was then applied to two databases with 12-lead ECG signals recorded inside and outside an MRI scanner. Reliable results for both databases were achieved for the ECG signals recorded inside (DBMRI: sensitivity Se = 99.94%, positive predictive value +P = 99.84%) and outside (DBInCarT: Se = 99.29%, +P = 99.72%) the MRI. Due to the accurate R-peak detection in real-time this can be used for monitoring and triggering in MRI exams.
Preprocessing of unipolar signals acquired by a novel intracardiac mapping system
Authors: Huck Salina , Oesterlein Tobias , Luik Armin , Schmitt Claus , Wakili Reza , Dössel Olaf 
Published: December 2016

Abstract
The novel high-density mapping system Rhythmia
TM
Medical (Boston Scientific, Marlborough, USA) allows a fast and automatic acquisition of intracardiac electrograms (EGMs). For recording the ORION mini-basket catheter is used. Due to the small electrode surface, the spatial averaging is smaller than with other commonly used mapping catheters. This results in a higher quality of unipolar signals. However, these are still corrupted by noise such as high frequency interference. Within this project, methods were developed and benchmarked that can be applied to detect and remove these undesired components. An algorithm was implemented to detect and eliminate artificial peaks in the spectrum of the EGM. The filtered signals showed improved quality in time domain. The performance of the spectral peak detection resulted in a median sensitivity of 92.1% and in a median positive predictive value of 91.9%.
Continuous non-invasive monitoring of blood pressure in the operating room: a cuffless optical technology at the fingertip
Authors: Solà Josep , Proença Martin , Braun Fabian , Pierrel Nicolas , Degiorgis Yan , Verjus Christophe , Lemay Mathieu , Bertschi Mattia , Schoettker Patrick 
Published: December 2016

Abstract
Routine monitoring of blood pressure during general anaesthesia relies on intermittent measurements with a non-invasive brachial cuff every five minutes. This manuscript provides first experimental evidence that a physiology-based pulse wave analysis algorithm applied to optical data (as provided by a standard fingertip pulse oximeter) is capable of accurately estimating blood pressure changes in-between cuff readings. Combined with the routine use of oscillometric cuffs, the presented novel approach is a candidate technology to increase patient safety by providing beat-to-beat hemodynamic measurements without the need of invasive monitoring procedures.
Application of microwave sensor technology in cardiovascular disease for plaque detection
Authors: Wagner David , Vogt Sebastian , Jamal Farabi Ibne , Guha Subhajit , Wenger Christian , Wessel Jan , Kissinger Dietmar , Pitschmann Kai , Schumann Ulrich , Schmidt Bertram , Detert Markus 
Published: December 2016

Abstract
Arteriosclerosis and associated cardiovascular disease remains the leading cause of mortality. Improved methods for vascular plaque detection allow early diagnose and better therapeutic options. Present diagnostic tools require intense technical expenditure and diminish value of modern screening methods. Our group developed an microwave sensor for on-site detection of plaque formation in arterial vessels. The sensor is an oscillator working around 27 GHz which is coupled to a microstrip stub line. The final flexible polyimid interposer has a length of 38 cm, a width of 1.2 mm and a thickness of 200 μm. Because of its minimal size the interposer completed a catheter with a diameter of 8F ready for further clinical use in cardiology and heart surgery.
Artificial blood circulatory and special Ultrasound Doppler probes for detecting and sizing gaseous embolism
Authors: Stark Philipp , Kalkbrenner Christoph , Braß Patrick , Brucher Rainer 
Published: December 2016

Abstract
This paper presents a special designed artificial blood circulatory (ABC) for studying gaseous embolism based on detection of gaseous emboli and their sizing using ultrasound (US) spectral Doppler. Blood mimicking fluid (BMF) was used in the circulatory to get valid results without using human blood. The additional necessary degassing circulatory shows a promising effect of decontaminating the BMF from air bubbles. This offers the base for detecting and sizing microemboli using special algorithms and finally leads to reliable calculations of dangerous embolism and its air volume. Standard US probes at an integrated tissue model and a new 8-MHz central catheter ultrasound (CCUS) probe inside a superior vena cava model (SVCM) are used and deliver the Doppler spectrogram as input for automatic emboli detection and further signal analysis. First results using the newly developed 8-MHz CCUS probe inside the SVCM and its Doppler spectrogram characteristics show promising results but need more detailed studies.
A method to determine the kink resistance of stents and stent delivery systems according to international standards
Authors: Brandt-Wunderlich Christoph , Schwerdt Christopher , Behrens Peter , Grabow Niels , Schmitz Klaus-Peter , Schmidt Wolfram 
Published: December 2016

Abstract
The kink behavior of vascular stents is of particular interest for clinicians, stent manufacturers and regulatory as a kinked stent generates a lumen loss in the stented vessel and can lead to in-stent restenosis. In this study methods to determine the kink resistance of stents and stent delivery systems according to the ISO 25539-2 and FDA guidance no. 1545 were presented. The methods are applicable for balloon expandable stents as well as for self-expanding stents and determine the lumen loss and residual diameter change dependent on the specific bending radius.
Comparison of stented bifurcation and straight vessel 3D-simulation with a prior simulated velocity profile inlet
Authors: Wüstenhagen Carolin , Borowski Finja , Grabow Niels , Schmitz Klaus-Peter , Stiehm Michael 
Published: December 2016

Abstract
Coronary diseases are the main reason for death in the western world. Bio-fluid mechanical correlations with arterial diseases are in the focus of our research. To treat occluded vessels, stents are implanted. Stent implantations can be associated with blood flow disruptions leading to restenosis or thrombosis formation. Numerical flow simulation is a promising tool to evaluate the hemodynamic performance of cardiovascular implants, but is resource-intensive in time and computational power. Therefore, a reduction in grid size would be beneficial due to economic exploitation of computational cost. The purpose of this numerical investigation is to substitute the computational domain of a distal stented bifurcation with a stented straight vessel by using the right inlet condition. The deviation of the results of the two different methods to simulate the blood flow situation in a bifurcation is marginal. This inlet can be used for standardised simulations of bifurcations were lesions commonly occur.
Transient Euler-Lagrange/DEM simulation of stent thrombosis
Authors: Stiehm Michael , Wüstenhagen Carolin , Grabow Niels , Schmitz Klaus-Peter 
Published: December 2016

Abstract
Stent implantation is the treatment of choice for cardiovascular diseases. By introduction of biodegradable thick strut stents investigations of thrombosis formation is one focus of research. This study deals with a transient Euler-Lagrange/DEM approach to simulate the flow field, platelet movement and clotting. The recirculation zones prolong particle residence time. As a result, the vicinity of stent struts shown a particularly higher risk for stent thrombosis.
Automated control of the laser welding process of heart valve scaffolds
Authors: Weber Moritz , Hoheisel Anna L. , Glasmacher Birgit 
Published: December 2016

Abstract
Using the electrospinning process the geometry of a heart valve is not replicable by just one manufacturing process. To produce heart valve scaffolds the heart valve leaflets and the vessel have to be produced in separated spinning processes. For the final product of a heart valve they have to be mated afterwards. In this work an already existing three-axes laser was enhanced to laser weld those scaffolds. The automation control software is based on the robot operating system (ROS). The mechatronically control is done by an Arduino Mega. A graphical user interface (GUI) is written with Python and Kivy.
Determination of the membrane hydraulic permeability of MSCs
Authors: Lopez Jennifer Contreras , Lauterböck Lothar , Glasmacher Birgit 
Published: December 2016

Abstract
A successful cryopreservation is based on knowledge of the optimal cooling rate. So far, this is often determined by way of complex parameter studies. Alternatively, the identification of cell specific characteristics, such as osmotic behaviour, membrane hydraulic permeability and activation energy could be used to calculate the optimal cooling rate. These parameters should be determined for supra-zero and sub-zero temperatures. In this study cryomicroscopy was used. Mesenchymal stromal cells (MSCs) from bone marrow were analysed. The determined membrane hydraulic permeability for sub-zero temperatures is significantly lower than that for supra-zero temperatures. On the contrary the activation energy is significantly higher in the presence of ice. The addition of a cryoprotective agent (CPA) such as dimethyl sulfoxid (DMSO) shows an additional influence on the characteristics of the membrane of the cell. The optimal cooling rate was determined with these parameters. For cryopreservation without DMSO the optimal cooling rate was found to be 12.82 K/min. If the MSCs were frozen with 5% (v/v) DMSO the optimal cooling rate is 16.25 K/min.
Medication process in Styrian hospitals
Authors: Hahnkamper Patrick , Baumgartner Christian , Schröttner Jörg 
Published: December 2016

Abstract
The aim of this work was to analyse the medication process and the potential for errors during the process steps. For this purpose, a literature review was conducted and a questionnaire was developed to compare the results from the literature with the current medication process in Styrian hospitals. The questionnaire was divided into four different parts with a total of 29 questions. For the survey all 37 Styrian hospitals were contacted whereas 11 filled out the questionnaire. The survey showed that there is no standardized medication process defined and that the rate of medication errors is generally underestimated. In addition, technical solutions may help to reduce errors but are expected to be hardly used in clinical practice.
Control tower to surgical theater
Authors: Buccioli Matteo , Traldi Leo 
Published: December 2016

Abstract
The main social priority is to reduce public debt and to streamline national health service (NHS) costs. Consequently, health managers need to acquire operating methods within their managerial structures so that all available resources are better planned in terms of effectiveness and efficiency, without compromising patient safety. In order to identify the information categories needed to know the whole surgical process is necessary to divide these in two main categories, supply and demand. Demand Information Group (DIG) contains the information that identify patients and its needs in terms of care. Instead Supply Information Group (SIG) contains information about hospital resources in order to cover the supply. The surgical process analyzed in terms such as industrial production process has the goal of produce the “health product for the patient” and its central part is performed in the operating room by a surgical team. This does not mean that the precedent and subsequent phases of the operating room have minor importance, in fact to obtain a high quality “health product” and reduce to a minimum the clinical risks related to the patient it is necessary that each phase of the process is carried out in the right way. The implementation of a Control Tower Approach allows for the management of productive process, able to guide hospital managers to identify the best strategies and to improve the risk management of patient safety in response to the guidelines of the World Health Organization.
Development of a skull phantom for the assessment of implant X-ray visibility
Authors: Hoffmann Thomas , Klink Fabian , Boese Axel , Fischer Karin , Beuing Oliver , Rose Georg 
Published: December 2016

Abstract
The paper presents the development and test of a skull phantom, which can be used for the assessment of the radiographic visibility of neurovascular implants. State of the art methods are based on specimens of the human skull. These are highly individual and not suitable for comparison of different radiographic data sets. The development process of the skull phantom is described from data generation to image processing, design and manufacturing using 3D printing. An experimental setup is recommended to generate reproducible data sets for implant visibility assessment with bone mimicking structures of the phantom. The model is evaluated by qualitative comparison with equivalent data sets of the original human skull model. The results show, that contrast characteristics of the phantom and the human skull model are similar. X-ray attenuation of the human bone is higher than the polymeric phantom material. The introduced phantom allows the determination of X-ray attenuation characteristics of different neurovascular implants for medical approval and testing processes.
Improvement of a subviral particle tracker by the use of a LAP-Kalman-algorithm
Authors: Rausch Andreas , Müller Dennis , Schanze Thomas 
Published: December 2016

AbstractAutomated detection and tracking of subviral particles is a promising method to obtain insights in complicated virus-cell interactions. This paper describes the implementation of a linear assignment problem solver and a Kalman-filter in an existing particle tracking algorithm. Two different simulated image sequences are used for the evaluation of the algorithms. Tracking and detection results of the new implemented solver are compared to the results of the original algorithm. The improved algorithm is able to improve the results by closing gaps in the particle tracks.
EyeGuidance – a computer controlled system to guide eye movements
Authors: Köhler Bernd , Bretthauer Georg , Guthoff Rudolf F. , Reichert Klaus-Martin , Sieber Ingo , Stachs Oliver , Toso Lorenzo , Allgeier Stephan 
Published: December 2016

Abstract
The densely innervated human cornea is the only superficial tissue of the human body in which nerve fibres are accessible in vivo by corneal confocal microscopy (CCM). Morphological parameters of the corneal sub-basal nerve plexus (SNP) derived from CCM images can potentially serve as a sensitive biomarker for early diagnosis of various neurodegenerative diseases. The evaluation of a single image with a typical field of view of 0.16 mm2 is insufficient for robust morphometric assessment. Mosaicking approaches have therefore been proposed to examine the SNP on a larger scale. Here we present a highly automated technique that significantly facilitates the generation of mosaic images of the SNP and is suitable for clinical tests.
US/MRI fusion with new optical tracking and marker approach for interventional procedures inside the MRI suite
Authors: Nagaraj Yeshaswini , Menze Bjoern , Friebe Michael 
Published: December 2016

Abstract
Interventional MRI in closed bore high-field systems is a challenge due to limited space and the need of dedicated MRI compatible equipment and tools. A possible solution could be to perform an ultrasound procedure for guidance of the therapy tools outside the bore, but still on the MRI patient bed. That could track and subsequently combine the superior images of MRI with the real-time features of ultrasound. Conventional optical tracking systems suffer from line of sight issues and electromagnetic tracking does not perform well in the presence of magnetic fields. Hence, to overcome these issues a new optical tracking system called inside-out tracking is used. In this approach, the camera is directly attached to the US probe and the markers are placed onto the patient to achieve the location information of the US slice. The evaluation of our novel system of framed fusion markers can easily be adapted to various imaging modalities without losing image registration. To confirm this evaluation, phantom studies with MRI and US imaging were carried out using a point-registration algorithm along with a similarity measure for fusion. In the inside-out system approach, image registration was found to yield an accuracy of upto 4 mm, depending on the imaging modality and the employed marker arrangement and with that provides an accuracy that cannot be easily achieved by combining pre-operative MRI with live ultrasound.
3D segmentation of thyroid ultrasound images using active contours
Authors: Poudel Prabal , Hansen Christian , Sprung Julian , Friebe Michael 
Published: December 2016

Abstract
In this paper, we propose a method to segment the thyroid from a set of 2D ultrasound images. We extended an active contour model in 2D to generate a 3D segmented thyroid volume. First, a preprocessing step is carried out to suppress the noise present in US data. Second, an active contour is used to segment the thyroid in each of the 2D images. Finally, all the segmented thyroid images are passed to a 3D reconstruction algorithm to obtain a 3D model of the thyroid. We obtained an average segmentation accuracy of 86.7% in six datasets with a total of 703 images.
Classification of indirect immunofluorescence images using thresholded local binary count features
Authors: Singh Susaiyah Allmin Pradhap , Pathan Suhail Parvaze , Swaminathan Ramakrishnan 
Published: December 2016

Abstract
Computer aided classification of HEp-2 cell based indirect immunofluorescence (IIF) images is a recommended procedure for standardising autoimmune disease diagnostics. In this work a novel feature, the thresholded local binary count (TLBC) has been proposed to classify IIF images into one among six classes. The TLBC is rotational invariant and is insensitive to pixel quantization noise. It characterizes the local binary gray scale pixel information in an image. The proposed feature along with global features such as area, entropy, illumination level and mean intensity, when classified using a support vector machine gave an accuracy of 86%. This feature could help in improving the diagnostics of autoimmune diseases which is highly clinically significant.
Fabrication of a compliant phantom of the human aortic arch for use in Particle Image Velocimetry (PIV) experimentation
Authors: Hütter Larissa , Geoghegan Patrick H. , Docherty Paul D. , Lazarjan Milad S. , Clucas Donald , Jermy Mark 
Published: December 2016

Abstract
Compliant phantoms of the human aortic arch can mimic patient specific cardiovascular dysfunctions in vitro. Hence, phantoms may enable elucidation of haemodynamic disturbances caused by aortic dysfunction. This paper describes the fabrication of a thin-walled silicone phantom of the human ascending aorta and brachiocephalic artery. The model geometry was determined via a meta-analysis and modelled in SolidWorks before 3D printing. The solid model surface was smoothed and scanned with a 3D scanner. An offset outer mould was milled from Ebalta S-Model board. The final phantom indicated that ABS was a suitable material for the internal model, the Ebalta S-Model board yielded a rough external surface. Co-location of the moulds during silicone pour was insufficient to enable consistent wall thickness. The resulting phantom was free of air bubbles but did not have the desired wall thickness consistency.
Effect of the number of electrodes on the reconstructed lung shape in electrical impedance tomography
Authors: Schullcke Benjamin , Krueger-Ziolek Sabine , Gong Bo , Moeller Knut 
Published: December 2016

Abstract
Electrical impedance tomography (EIT) is used to monitor the regional distribution of ventilation in a transversal plane of the thorax. In this manuscript we evaluate the impact of different quantities of electrodes used for current injection and voltage measurement on the reconstructed shape of the lungs. Results indicate that the shape of reconstructed impedance changes in the body depends on the number of electrodes. In this manuscript, we demonstrate that a higher number of electrodes do not necessarily increase the image quality. For the used stimulation pattern, utilizing neighboring electrodes for current injection and voltage measurement, we conclude that the shape of the lungs is best reconstructed if 16 electrodes are used.
Computer assisted assessment of progressing osteoradionecrosis of the jaw for clinical diagnosis and treatment
Authors: Kober Cornelia , Kjeller Göran , Sader Robert , Zeilhofer Hans-Florian , Berg Britt-Isabelle 
Published: December 2016

Abstract
Osteoradionecrosis (ORN) is a serious side effect of oncologic radiation therapy. Often, surgical removal of the affected skeletal tissue is indicated. In cranio-maxillofacial surgery, partial or total resection of the upper or lower jaw implies a severe impairment of the patient‘s quality of life. Up to now, clear display of ORN is still a challenge. This part of the project is dedicated to medical visualization of progressing ORN for clinical diagnosis. Currently, clinical diagnosis of ORN is mostly based on computer tomography (CT). With regard to its high advantages as e.g. reduced radiation dose, we additionally evaluate cone beam computer tomography (CBCT). After registration on a suitable reference and refined image processing and segmentation, all patient’s CT-/CBCT-data are subjected to various rendering techniques configured for the respective purpose, namely visualization of destructive and/or sclerotic skeletal alterations, consideration of cortical or trabecular bone, and analysis based on CT or CBCT. Recent achievements within the project were demonstrated with special focus on evaluation of both, CT and CBCT as well as on close cooperation with the clinical setting.