Current Directions in Biomedical Engineering

Open Access Published by De Gruyter

Volume 4 Issue 1

Issue of Current Directions in Biomedical Engineering

Contents
Journal Overview

Open Access September 22, 2018

Interactive implants: vision and challenges

Hoffmann Klaus-Peter, Olze Heidi, Kneist Werner, Krüger Thilo, Droste Wiebke, Ruta Marc, Rupp Rüdiger

Page range: 1-4

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Abstract

Different complex physiological functions might be restored by means of distributed active implants. Wireless communication between the implants, on the one hand, and an external control unit, on the other hand, is necessary to synchronize electrical stimulation of neural and muscular tissue. Seventeen project partners from industries, universities, healthcare providers and research organizations closely cooperate in the framework of the BMBF Innovation Cluster “Interactive Implants (INTAKT)”. The goal of this cluster is to develop and evaluate networks of distributed implants. Challenges of the project include complex interaction between humans and technology, wireless power supply, long-term stability of implants as well as secure and safe signal transmission [1].

Open Access September 22, 2018

Tinnitus suppression using electrical stimulation

Heidi Olze, Agnieszka J. Szczepek, Uta Reich, Stefan Gräbel, Florian Uecker

Page range: 5-8

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Abstract

Tinnitus is a phantom sound perceived only by the affected person. Although the causes for tinnitus may be very diverse (e.g. hearing loss, cardiovascular diseases, diabetes, Meniere’s disease, otosclerosis), they all lead to pathological activation of the auditory pathway. Cochlear implants are electronic inner ear prostheses used to restore the hearing abilities of hard of hearing people. It has been noticed that the cochlear implants not only enable hearing but also reduce tinnitus that usually accompanies deafness and hearing loss. One of the likely mechanisms behind the latter phenomena is thought to be the unknown properties of electrical stimulus. This project was designed as a proof of concept for a device, which would be sending the tinnitus-suppressing electrical signal. To achieve this, the project was split into a preclinical part using experimental animals (guinea pigs) and a clinical trial part with tinnitus patients. In the preclinical part, together with Inomed Medizintechnik GmbH, we are testing the physical design and biocompatibility of anti-tinnitus implant. In the clinical part of the project, we use an electrical stimulation in the ear canal, through the eardrum (tinnitus patients), or via cochlear implant in a sample of cochlear implant patients (pre- and post-implantation). We ask the patients to mark the loudness of their tinnitus on a visual scale from 1 to 10 before, during and after routine electrical stimulation and quality of the tinnitus The results obtained during our preclinical and clinical testing as well as future plans will be presented and discussed.

Magnetic particle imaging (MPI) is a novel tomographic imaging modality which uses static and dynamic magnetic fields to measure the magnetic response generated by superparamagnetic iron oxide nanoparticles (SPIONs). For the characterization of the SPIONs magnetic particle spectroscopy (MPS) is used. In the current research, a low noise amplifier (LNA) suitable for MPI and MPS is presented. LNA plays a significant role in the receive chain of MPI and MPS by amplifying the signals from the nanoparticles while keeping the noise induced through its own circuitry minimal. The LNA is based on the summing configuration and fabricated on a printed circuit board (PCB). Moreover, the prototyped LNA is compared with a commercially available pre-amplifier. The input voltage noise of the prototyped LNA with a receiving coil of series resistance of 0.551 mΩ and an inductance of 130 μH is 561 pV/ √ Hz with a noise figure (NF) of 11.57 dB.

Open Access September 22, 2018

Progress and challenges in the development of novel implant concepts for cardiovascular, ophthalmologic and otolaryngologic applications

Current research and development activities of the Twenty20 consortium

Niels Grabow, Klaus-Peter Schmitz

Page range: 87-88

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Abstract

Medical device innovations may contribute to the reconstruction of biological functions, and thereby improve the quality of patients’ lives, as well as extend their life expectancy. The coordinated research project “RESPONSE - Partnership for Innovation in Implant Technology” (BMBF program Twenty20 - Partnership for Innovation, 2014 - 2021) is focusing on the development of novel concepts for implantable medical devices for cardiovascular, ophthalmologic and otorhinolaryngologic applications. The joint research efforts of academia and industry in the RESPONSE consortium address the challenges in implant design, biofunctionalization, process development and production. Particular attention is paid to the process of translation of medical device innovations, cost analysis, as well as health technology assessment.

The open, cross-vendor interoperability of medical devices is an enabling technology for the implementation of context-aware biomedical systems in daily clinical routine. The surgical working environment is both a valuable field of application and a particular challenge. A design of context-aware medical technologies that shows intelligent behaviour and ensures safe operation is demanding; thus implementations are yet limited to prototypes and specific surgical use cases. Many open research questions need to be addressed to empower context-aware medical systems to be a relief and not a burden for the clinical user.

Open Access September 22, 2018

The opportunities of biodynamic lighting in homes for the elderly

Melanopic measurements and experiences from three senior citizen facilities

Herbert Plischke, Matthäus Linek, Johannes Zauner

Page range: 123-126

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Abstract

Light is an important factor for regulation of circadian, endocrine and metabolic processes in the human body. Through this light has a positive effect on cognition, on the stabilization of circadian rhythms and for general wellbeing. These effects are described as non-visual effects of light. Many dynamic lighting systems are already in use in workplaces and living spaces, aiming to address visual and also non-visual effects. In Europe and US the term “Human Centric Lighting” or abbreviated "HCL” was introduced, as a scientifically agreed concept on how to plan non-visual effects of artificial light in synergy with natural light. Older people, especially with neurological and psychological diseases can especially benefit from this lighting concept. However, in order to achieve the desired non-visual effects, certain conditions should be fulfilled. In Germany the DIN SPEC 67600 is a guideline for the design of biologically effective illumination, with examples for senior- and nursing homes. A goal of this evaluation was to check whether the recommendations of the specification DIN SPEC 67600 in three nursing homes were met and another goal was if effectiveness of the lighting on residents and nursing staff can be determined. Photometric measurements were taken and subjective perceived non-visual effects of light were surveyed using a questionnaire. Results: Although none of the three facilities met all the criteria of the DIN SPEC 67600 guidelines, non-visual lighting effects on residents and nursing staff could be detected. The results also indicate that careful attention should be paid on maintenance of HCL systems. The correct use of HCL solutions in homes for the elderly has opportunities to improve health status if the system is properly designed and maintained. Therefore next to the existing (non-visual) metrics and HCL design guidelines, guidelines for maintaining and regular inspections should be established.

Our work focuses on enhancing the illumination optics of a rigid medical endoscope using optomechanical simulation. We aim on improving the efficiency of the illumination optics to provide more light in the surgeon’s field of view (FOV) and therefore better image quality. We conducted an extensive market analysis and measured several rigid endoscopes and their external light sources in the lighting technology laboratory. Surprisingly, all endoscopes showed a degree of efficiency below 20 %. Our optimization approach is based first on a photometric and colorimetric analysis carried out with an integrating sphere and a goniophotometer. Secondly, the results obtained are implemented in a 3Doptomechanical simulation model developed with the raytracing software LightTools (Synopsis©). In the simulation model both the geometrical components as well as the critical interfaces are examined considering light coupling at boundary surfaces and light transfer within the illumination optics. Moreover, the optimization takes into account spectral power distribution (SPD) and angular light distribution (ALD) of the light provided from the fiberoptic cable connected to an external light source as well as additional interfering factors like gluing, dispersive absorption and total reflection at critical angles.

Open Access September 22, 2018

Effects of local activation times on the tension development of human cardiomyocytes in a computational model

Armin Müller, Ekaterina Kovacheva, Steffen Schuler, Olaf Dössel, Lukas Baron

Page range: 247-250

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The development of a drug against pathogens of hemorrhagic fever, like the Marburg virus, is a great challenge. Therefore, accurate knowledge of the properties of subviral particles in the host cell must be obtained. The base for subviral particle analysis is a special fluorescence microscopy technique. In order to automate and visualize the subviral particles’ motion patterns, previously a tracking algorithm was developed. In this article a new algorithm to parameterize and visualize the achieved particle tracks is introduced. A good potential for a fast data recognition is shown, with constantly respecting a high usability for pharmaceutical researchers. This algorithm was tested on both simulated and real data and provides reproducible results.

Open Access September 22, 2018

Magnetoneurograhy of an Electrically Stimulated Arm Nerve

Usability of Magnetoelectric (ME) Sensors for Magnetic Measurements of Peripheral Arm Nerves

Eric Elzenheimer, Helmut Laufs, Tilmann Sander-Thömmes, Gerhard Schmidt

Page range: 363-366

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Abstract

For further development and optimization of novel uncooled magnetoelectric (ME) sensors, a better understanding of spectral power distribution and signal strength of nerve signals is of high interest. For obtaining information on these signal properties, Superconducting Quantum Interference Device (SQUID) measurements were performed at the Physikalisch-Technische Bundesanstalt (PTB) in Berlin. Signal amplitudes were subject-dependent and ranged from 17 fT to 60 fT in a frequency range from 100 Hz to 1 kHz. The required SQUID averaging time was in the range of minutes, while for current ME sensors significantly longer averaging times are expected to be necessary.

Open Access September 22, 2018

Measuring of calcification risk with polymer microchips

Julia Bavendiek, Johannes Sackmann, Werner Karl Schomburg, Steffen Gräber, Wilhelm Jahnen-Dechent, Andreas Pasch

Page range: 367-370

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Abstract

It has been shown that the formation of calcium phosphate crystals can be detected in patient blood using a polymer microchip manufactured by ultrasonic processing. Ultrasonic processing is recently evolving for the fabrication of low-cost microfluidic devices from thermoplastic polymers. The formation of calcium phosphate crystals can be measured in the blood serum of a patient both optically from a change in turbidity or in electrical resistance.

Within this work we demonstrate a UV-Lithography based method for the fabrication of microgrooves on titanium surfaces. The microgroove period, depth and profile form are easily controllable by process parameters. By controlled under-etching of a lithographically structured photo resist, different profile forms from nearly rectangular, over curvy/spiked to sinus-shaped forms with different amplitudes and sizes can be realized. The resulting microgrooves can be directly used as implant or implant abutment surfaces to enhance soft tissue integration or to create molds for cell/substrate interaction studies. Due to the lithographic process the whole method is highly controllable and reproducible.

About this journal

Objective
Current Directions in Biomedical Engineering (CDBME) is an open access journal publishing proceeding papers, often from the annual BMTE, CURAC, and TAR conferences, but also others. It is closely related to the journal Biomedical Engineering - Biomedizinische Technik (BME-BMT) that is well established and has published articles of high quality for more than 50 years. CDBME is as BME-BMT a forum for the exchange of knowledge in the fields of biomedical engineering, medical information technology and biotechnology/bioengineering for medicine and addresses engineers, natural scientists, and clinicians working in research, industry, or clinical practice.

Topics

Diagnostic Imaging
Biosignal Processing, Biomechanics, Image Processing, Modelling and Simulation
Information and Communication in Medicine, Telemedicine and e-Health
Surgery, Minimum Invasive Interventions, Endoscopy and Image Guided Therapy
Diagnostic and Therapeutic Instrumentation, Clinical Engineering
Micro- and Nanosystems in Medicine, Active Implants, Biosensors
Neuroengineering, Neural Systems, Rehabilitation and Prosthetics
Biomaterials, Cellular and Tissue Engineering, Artificial Organs
Biomedical Engineering for Audiology, Ophthalmology, Emergency and Dental Medicine

Article formats
Conference Proceedings Papers