About
38
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Introduction
Steffen Kaufmann currently works as Global Technical Innovation Manager at BSN medical an Essity company. Steffen does research in Biomedical engineering, Electrical Engineering and Electronic Engineering.
Additional affiliations
November 2014 - present
June 2014 - December 2014
March 2010 - June 2014
Publications
Publications (38)
Electrical impedance tomography (EIT) is an imaging method that is able to estimate the electrical conductivity distribution of living tissue. This work presents a field programmable gate array (FPGA)-based multi-frequency EIT system for complex, time-resolved bioimpedance measurements. The system has the capability to work with measurement setups...
Bioimpedance measurements are a non-invasive method to determine the composition of organic tissue. For measuring the complex bioimpedance between two electrodes, an alternating current with a constant amplitude is injected into the tissue. The developed voltage drop is used to calculate the real and imaginary part of the impedance under test. Meas...
The measurement of the pulse wave has proven to be a vital tool in medical diagnosis. Whereby most pulse wave measurements are carried out at extremities, this work proposes a system for measuring the pulse wave and the Pulse Arrival Time (PAT) in the interior of the ear. The developed measurement device is based on a battery powered microcontrolle...
Pulse wave measurements provide vital information in medical diagnosis. For this reason, a measurement system is developed for determining the transient time of the pulse wave between the heart and the ear. To detect pressure variations in the sealed ear canal, caused by the arriving pulse wave, an in-ear sensor is developed which uses heart sounds...
The measurement of the pulse wave has proven to be a vital tool in medical diagnosis. Whereby most pulse wave measurements are carried out at extremities, this work proposes a system for measuring the pulse wave and the Pulse Arrival Time (PAT) in the interior of the ear. The developed measurement device is based on a battery powered microcontrolle...
Objective: Bioimpedance measurements are mostly performed utilizing gel electrodes to decrease the occurring electrode-skin impedance. Since in many measurement environments this kind of electrode is not appropriate, the usability of dry electrodes is analysed. Approach: The development of five different kinds of dry electrodes, including gold, sta...
Objective: Bioimpedance measurements are mostly performed utilizing gel electrodes to decrease the occurring electrode-skin impedance. Since in many measurement environments this kind of electrode is not appropriate, the usability of dry electrodes is analysed. Approach: The development of five different kinds of dry electrodes, including gold, sta...
The Potential for Improved Patient Recovery Through Reduced Noise – A Sound Level Comparison of Different Negative Pressure Wound Therapy (NPWT) devices
Pulse wave measurements provide vital information in medical diagnosis. For this reason, a measurement system is developed for determining the transient time of the pulse wave between the heart and the ear. To detect pressure variations in the sealed ear canal, caused by the arriving pulse wave, an in-ear sensor is developed which uses heart sounds...
Electrical impedance tomography (EIT) is an imaging method that is able to estimate the electrical conductivity distribution of living tissue. This work presents a field programmable gate array (FPGA)-based multi-frequency EIT system for complex, time-resolved bioimpedance measurements. The system has the capability to work with
measurement setups...
In diesem Kapitel werden die notwendigen Theorien und Verfahren beschrieben, die für die Messung von Bioimpedanzen notwendig sind. So wird beginnend mit der Definition der elektrischen Impedanz der physikalische bzw. physiologische Zusammenhang zur Bioimpedanz hergestellt. Anschließend wird der Stand der Technik möglicher Messprinzipien vorgestellt...
Auf Basis des entwickelten EIT-Systems werden in diesem Kapitel Verbesserungsmöglichkeiten abgeleitet und für die nachfolgende Konzeption eines Aktivelektroden-Systems verwendet. So wurde im Verlauf dieser Arbeit dargestellt, dass die kapazitiven Eigenschaften der Zuleitungen zu den Elektroden einen entscheidenden Einfluss auf das Messergebnis habe...
Nach der Beschreibung des Entwicklungszyklus des BMS erfolgt nun, wie in Kapitel 1.3 dargelegt, die Beschreibung von Entwicklung, Verifikation und Test des realisierten Mehrfrequenz-EIT-Systems, welches im Wesentlichen als Erweiterung des BMS aufgefasst werden kann. Die Verifikation des EIT-Systems erfolgt sowohl an Widerstands- als auch an Tankpha...
Wie in Kapitel 1.3 dargelegt, erfolgt nach der Beschreibung der Grundlagen der Bioimpedanzmessung und der EIT nun in diesem Kapitel die Beschreibung von Entwicklung, Aufbau, Test und Verifikation des Bioimpedanzmesssystems (BMS). Dabei wird ausgehend von der Anforderungsanalyse die grundlegende Systemarchitektur erarbeitet, welche anschließend mit...
Dieses Kapitel beschreibt die Funktionalität der EIT vom physikalischen Modell über die Aufnahme, Auswertung und Bewertung des Messwerts hin bis zur Rekonstruktion der eigentlichen Leitwertverteilung. Dabei wird das physikalische Modell der EIT als Erweiterung des eindimensionalen Impedanz- bzw. Leitwertsbegriffs auf eine zweibzw. dreidimensionale...
In the past years, different Magnetic Particle Imaging (MPI) scanners for small animals using a field free line (FFL) have been presented [1-3]. In this work, a novel concept of a pre-clinical FFL MPI scanner which can accommodate rabbits is presented.
Conventional methods to evaluate the size of superparamagnetic iron oxide nanoparticles (SPIONs) and their coatings used in magnetic particle imaging (MPI) include photon cross-correlation spectroscopy (PCCS) [1], atomic force microscopy (AFM) [1] and transmission electron microscopy (TEM) [2]. There is however still a potential for improvement as...
Steffen Kaufmann entwickelt ein Verfahren zur verbesserten Instrumentierung der Transferimpedanzmessung mit Fokus auf die Anwendung in der Elektroimpedanztomographie (EIT). Die Optimierung wird durch eine Erhöhung des Signal-Rauschabstandes erreicht, gleichzeitig ermöglicht das Verfahren spektroskopische Mehrfrequenz-Messungen, mit einer Auflösung...
The measurement of the pulse wave has proven to be a vital tool in medical diagnosis. Whereby most pulse wave measurements are carried out at extremities, this work proposes a system for measuring the pulse wave and the Pulse Arrival Time (PAT) in the interior of the ear. The developed measurement device is based on a battery powered microcontrolle...
Bioimpedance measurements are useful tools in biomedical engineering and life science. Bioimpedance is the electrical impedance of living tissue and can be used in the analysis of various physiological parameters. Bioimpedance is commonly measured by injecting a small well known alternating current via surface electrodes into an object under test a...
This research introduces a novel multi-modal vital parameter measurement system and with some measurements taken. The system is able to accurately and simultaneously measure a single channel Electrocardiogram (ECG), four Photoplethysmograms (PPG), the pressure in both ears, as well as the broadband, time resolved thorax bioimpedance (ICG). The desi...
The measurement of the pulse wave has proven to be a vital tool in medical diagnosis. Whereby most pulse wave measurements are carried out at extremities, this work proposes a system for measuring the pulse wave and the Pulse Arrival Time (PAT) in the interior of the ear. The developed measurement device is based on a battery powered microcontrolle...
The measurement of the Pulse wave Arrival Time
(PAT) has proven to be a vital tool in medical diagnosis.
Whereby most PAT measurements are carried out at extremities,
this work proposes the interior of the ear as a
new site. Due to pressure variations inside the auditory
canal a pulse wave can be measured by using a pressure
sensor or by simple in-...
Non-invasive bioimpedance measurement as a tool in biomedical
engineering and life sciences allows conclusions about condition and
composition of living tissue. For interfacing the electronic conduction
of the instrumentation and the ionic conduction of the tissue,
electrodes are needed. A crucial point is the uncertainty arising from
the unknown,...
Bioimpedance is proving to be a very vital tool in analysis of various physiological parameters in the human body such as cardiac output and stroke volume of the heart, because of its non-invasiveness and real-time continuous monitoring. The conductivity curve can be obtained by introducing a small known alternating current via surface electrodes i...
Electrical Impedance Tomography (EIT) is a functional real-time imaging technique, used mainly in medical applications. EIT is based on impedance measurements and its spatial reconstruction within an object under test. For the measurements small well known alternating currents (AC) are injected via electrodes into the object under test. The resulti...
Electrical Impedance Tomography (EIT) is a real-time imaging modality that measures and reconstructs the spatial impedance distributions inside an object under test. Based on the injection of small well know alternating currents (AC) and the measurement of resulting voltages, EIT has no known hazards and is even painless for human beings. Advantage...
Electrical impedance tomography (EIT) is a functional real-time imaging technique based on measurement and reconstruction of electrical impedance distributions.
Until now EIT is mainly known for the visualization of breathing and the lungs, this paper presents a new EIT system, designed for intracranial applications. In intracranial EIT, electrodes...
Magnetic Particle Imaging (MPI) is a quite new imaging technique, based on the non-linear magnetization behavior of superparamagnetic iron oxide nanoparticles (SPIOs). These SPIOs are applied to a patient as tracer material. An important key aspect for successful and reliable imaging is tracer development and characterization. Hence, a Magnetic Par...
