BIODEVICES 2013 Abstracts


Full Papers
Paper Nr: 7
Title:

A 0.18µm CMOS 2nd Order Sigma-Delta Modulator for Low-power Biosensor Applications

Authors:

Ryan Selby and Tom Chen

Abstract: Silicon biosensors are becoming increasingly popular for the study of cell growth and movement in biological systems. These biosensors need small, low power, highly accurate sensors and analog to digital converters (ADCs) in order to generate chemical images of small tissue samples. Low-power and low-voltage design is key in battery operated systems, and the size of the circuits need to be kept small such that arrays of sensors can be placed on each chip. This paper presents a low-voltage, low-power, 2nd order Sigma-Delta modulator for use in an electrochemical biosensor system. The modulator was designed using a commercial 0.18μm CMOS process with a supply voltage of 0.9V. With an input signal bandwidth of 1kHz it achieves a SNDR of 61.2dB using an over-sampling ratio of 500. Power dissipation is 165μW and it occupies 0.0225mm2 of silicon area.

Paper Nr: 12
Title:

Beat-by-Beat Monitoring of Systolic Blood Pressure based on an ASIC and a Mobile Phone for Ambulatory Application

Authors:

Wenxi Chen, Ming Huang, Xin Zhu, Kei-ichiro Kitamura and Tetsu Nemoto

Abstract: This paper describes an ambulatory monitor for beat-by-beat monitoring of systolic blood pressure (SBP) based on an ASIC chip and a mobile phone. The ASIC is able to measure electrocardiogram (ECG), photoelectric plethysmogram (PPG), and has a peripheral interface to control an air pump and valve for inflating and deflating a sphygmomanometer cuff in conventional blood pressure measurement. Algorithms for signal processing, characteristic point detection and SBP estimation are implemented on a mobile phone. Pulse arrival time (PAT) is derived from the apex of QRS complex to the maximum slope of PPG, and is used to estimate a rapid change component in SBP beat-by-beat. An oscillometric sphygmomanometer with a cuff is used to determine SBP intermittently for calibration purpose. Data communication between a mobile phone and the ambulatory monitor is conducted via a Bluetooth wireless connection. Performance of the prototype is examined by data from five healthy college students. The results show that 65.9% of estimated SBP fall into ±5% relative error, 96.6% in ±10% and 99.7% in ±15%. This prototype is a pilot study aiming at integrating an innovative sphygmomanometry into a mobile phone for continuous blood pressure monitoring. We expect to find potential applications in ambulatory monitoring and daily healthcare.

Paper Nr: 13
Title:

Contactless Electrical Bioimpedance System for Monitoring Ventilation - A Biodevice for Vehicle Environment

Authors:

Raúl Macías Macías, Miguel Ángel García González, Juan Ramos Castro, Ramon Bragós Bardia and Mireya Fernández Chimeno

Abstract: Nowadays, automotive companies are focused in improving road traffic safety. For that, not only the vehicle performance is improved but also the driver behavior is monitored. This could be done in many ways. One of them is to monitor a specific physiological parameter using a biodevice. That device should be reliable enough to use in a very noisy environment like a vehicle is. Furthermore, because long-term monitoring is required, any invasive and annoying method should be avoided. Therefore, an electrical bioimpedance device capable of monitoring driver ventilation using several textiles electrodes has been designed and implemented.

Paper Nr: 14
Title:

Flexible Array of Active Concentric Ring Electrodes for Surface Bioelectrical Recordings - Application to Non-invasive Recordings of EEnG

Authors:

J. Garcia-Casado, V. Zena, G. Prats-Boluda, Y. Ye-Lin and E. Garcia-Breijo

Abstract: The estimation of laplacian potential on the body surface obtained by means of concentric ring electrodes can provide bioelectrical signals with better spatial resolution and less affected by bioelectrical interferences than monopolar and bipolar recordings with conventional disc electrodes. These ringed electrodes are usually implemented on rigid substrates which cannot adapt to body surface curvature. In this paper an array of flexible concentric ring electrodes for non-invasive bioelectrical activity recordings is presented. The array contains three tripolar electrodes in bipolar configuration (TCB, inner disc and external ring are shorted) which is suitable for body surface mapping. A preconditioning circuit module is directly connected to the electrode array to perform a first stage of filtering and amplification as close as possible to the recording area. Simultaneous recordings of intestinal myoelectrical activity (electroenterogram, EEnG) by means of the flexible array of ringed-electrodes and by disc electrodes with gel were carried out in healthy volunteers in fast state. Signals from the developed array of electrodes presented lower electrocardiographic and respiratory interference than conventional bipolar recordings with disc electrodes. The small bowel’s slow wave myoelectrical activity can be identified more easily in the ringed-electrodes recordings.

Paper Nr: 23
Title:

Portable Custom Built Device for Thermal Sensitivity Assessment - An Auxiliary Tool to Characterize the Neuropathic Pain following Spinal Cord Injury

Authors:

Renato Varoto, Fábio Casagrande Hirono, Fernando Ometto Zorzenoni, Ricardo Yoshio Zanetti Kido, William Barcellos and Alberto Cliquet Jr.

Abstract: Neuropathic pain is characterized to arise without stimulation of nociceptors, but due to injury or dysfunction of Peripheral and Central Nervous Systems. It involves altered mechanisms of impulse transmission in somatosensory pathways, causing abnormal sensations. Quantitative sensory testing, by the detection of thermal stimuli, is a method used to characterize and study the neuropathic pain. Therefore, this work describes the development and application of portable custom built device for cutaneous thermal sensitivity assessment in spinal cord injured subjects (SCIS). Using method of levels, the assessment was applied in healthy subjects and SCIS with and without neuropathic pain. The thresholds determined for healthy subjects during thermal sensitivity assessment are consistent and other results provided by clinical trials are according to previous works, demonstrating the device feasibility as an auxiliary tool for neuropathic pain study.

Paper Nr: 29
Title:

Bioimpedance Parameter as a Risk Factor to Assess Pine Decay - An Innovative Approach to the Diagnosis of Plant Diseases

Authors:

E. Borges, M. Sequeira, André F. V. Cortez, H. Catarina Pereira, T. Pereira, V. Almeida, T. M. Vasconcelos, I. M. Duarte, N. Nazaré, J. Cardoso and C. Correia

Abstract: Electrical impedance spectroscopy, EIS, has been proving efficacy and utility in a wide range of areas, from the characterization of biological tissues to living organisms. Several commercial solutions, with high precision and resolution, are available. Nonetheless, the typical equipments are expensive, unfeasible for in vivo and in field applications and unspecific for concrete applications. These features, together with the lately demands in the vegetal field, fundament this work. Actually, the fast spread of asymptomatic forest diseases, with no cure available to date, such as the pinewood disease, PWD, constitute a problem of economical and forestall huge proportions. Herein is proposed a portable EIS system, for biological applications, able to perform AC current or voltage scans within a selectable frequency range. The procedure and the results obtained for a population of 24 young pine trees (Pinus pinaster Aiton) are also presented. Pine trees were kept in a controlled environment and were inoculated with the nematode (Bursaphelenchus xylophilus Nickle), that causes the PWD, and also with bark beetles (Tomiscus destruens Wollaston). Some degree of discrimination between different physiological states was achieved. These results may constitute a first innovative approach to the diagnosis of such types of diseases.

Paper Nr: 37
Title:

A Single Electrical Acupuncture Needle with Bipolar Electrodes for Biotissue Discrimination

Authors:

Giseok Kang, Jae-Cheon Kim, Sohee Kim and Jong-Hyun Lee

Abstract: In oriental medicine, acupuncture is an essential treatment for the muscle tissue relaxation. For treatment, electrical stimulations to the tissue conducted with multiple electrical acupuncture needles have generally been used. However, the sting depth of a needle can be handled only by the sense of the oriental medicine doctor. Moreover, it is difficult to use multiple needles to focus the electrical stimulation on a tissue of small volume, and, likewise difficult to distinguish various tissues. In order to overcome the aforementioned shortcomings, we developed a single acupuncture needle that has bipolar electrodes on the surface of the needle tip by using a novel flexible parylene C film photomask. The interdigitated electrodes, 31.25 μm in width and 32.00 μm in gap, were passivated by parylene C film to prevent metal debris from spreading into the tissue. The electrical acupuncture needle was developed based on the conventional acupuncture needle (400 μm in diameter), so that the needle will give a familiar sensation to patients. We demonstrate the metal patterning technique with a high resolution that has less than 2.95 % dimensional error compared to the designed metal pattern dimensions. The biotissues were well distinguished by phase angle at 1 MHz of 14.6°, -32.7°, and 43.6° for skin, muscle, and ligament of a chicken, respectively.

Paper Nr: 40
Title:

Improving Neuron Stimulation Efficency by Altering Electrode Geometry

Authors:

A. Ghazavi, D. Westwick, C. Luk, N. I. Syed and C. Dalton

Abstract: Microelectrode arrays (MEA) are non-invasive tools for recording brain cell activity and have been successfully applied to a variety of neurons. However, MEAs fail where consistent stimulation of neurons is desired over an extended period of time. Here, a model is presented to study features that provide optimum stimulation threshold from different sizes and shapes of electrodes. Both simulation and in vitro experimental results suggest that star-shaped electrodes enable a threshold voltage that is 25% lower than that of an electrode with a circular shape, and are thus considered more efficient for neuronal stimulation. These findings are important as they will help produce more efficient microelectrode arrays for in vivo applications such as prosthetic devices, as well as for long-term in vitro neuron stimulation for studying neuronal networks and function.

Paper Nr: 42
Title:

Drowsiness Detection by Electrooculogram Signal Analysis in Driving Simulator Conditions for Gold Standard Signal Generation

Authors:

N. Rodríguez-Ibáñez, P. Meca-Calderón, M. A. García-González, J. Ramos-Castro and M. Fernández-Chimeno

Abstract: Detection of drowsiness while driving is a leading objective in advanced driver assistance systems. This work presents a new index to assess the alertness state of drivers based on the EOG dynamics derived from a polysomnography device. More than 15 hours of laboratory tests were analyzed in order to detect drowsiness while doing cognitive activities. The proposed method has a sensitivity of 92, 41% and a VPP of 93,41% in detecting drowsiness. The results show that the proposed index may be promising to assess the alertness state of real drivers.

Paper Nr: 51
Title:

Polymeric Micro Check Valve for Glaucoma Treatment - Considering Rate of Aqueous Humor Formation

Authors:

Chang-Ju Park, Jaekwon Lee, Byungphil Mun, Jae-Yong An, Seunghwan Moon and Jong-Hyun Lee

Abstract: This paper describes a novel glaucoma drainage device (GDD) to regulate intraocular pressure (IOP) considering the rate of aqueous humor formation. The device functionally consists of a polymeric cannula (silicone tube) and a micro check valve (PDMS: polydimethylsiloxane). The check valve has three layers: a top layer (cover), which has rounded edges to reduce fibrosis, an intermediate layer (thin movable valve membrane), and a bottom layer (base plate). A feedforward channel is employed in the top layer to prevent reverse flow by compensating the pressure of the outlet channel. The thickness of thin the PDMS membrane was determined considering the cracking pressure and the rate of aqueous humor formation. The cracking pressure in-vitro test was conducted at 15 mmHg, which lies within the normal intraocular pressure range (10 ~ 20 mmHg). The experimental mean value and standard deviation of the flow rate at the cracking pressure was 2.18 ± 0.69 µL/min, which is confirmed to cover the rate of aqueous humor formation in the normal human eye (1.5 ~ 3.4 µL/min). Flow in a reverse direction was not observed.

Paper Nr: 52
Title:

High Density Cell Electrofusion on Chip using an Array of Non-connected Metallic Pads

Authors:

Feriel Hamdi, Wei Wang, Frederic Subra, Elisabeth Dufour-Gergam, Olivier Français and Bruno Le Pioufle

Abstract: Cell fusion consists on creating a hybridoma cell containing the genetic properties of the progenitor cells. It can be performed chemically or electrically. The latter method, called Electrofusion, is a more efficient way to create hybrid cells investigated for antibody production or cancer immunotherapy. To envision this application, a high amount of hybrid cells is needed. This work presents an original design for high density electrofusion on chip. The structure consists of an array of non-connected electroplated gold pads patterned between two connected electrodes. While applying a Voltage on the connected electrodes, the Electric field is disturbed around the gold pads inducing a Dielectrophoretic Force on cells used to trap and pair them. When cells are paired, Electric pulses are applied to induce electrofusion. The absence of wire connections on the pads permits the high density trapping and electrofusion. Successful alignment and electrofusion of murine melanoma cells with this structure are demonstrated.

Paper Nr: 53
Title:

Non-Thermal Atmospheric Plasma for Endodontic Treatment

Authors:

Avinash S. Bansode, Aumir Beg, Swanandi Pote, Bushra Khan, Rama Bhadekar, Alok Patel, S. V. Bhoraskar and V. L. Mathe

Abstract: Gas discharge plasma is being explored nowadays for its application as an alternative to the conventional sterilization and disinfection techniques in medical sciences. We have developed the non-thermal atmospheric plasma torch to study the effect of plasma treatment on the growth rate of E. faecalis culture and biofilms. E. faecalis treated with plasma was then compared with helium gas exposed and chlorohexidine treated cultures and biofilms. All the results are analysed for significance (P < 0.001) using ANOVA and TUCKEY’S test. Optical emission spectroscopy technique has been employed in. situ to identify the species interacting with the samples. It is found that atmospheric non-thermal plasma proves to be a promising alternative to traditional disinfectants for disinfection during endodontic treatment.

Paper Nr: 61
Title:

A Novel and Low Cost Acoustic based Probe for Local Pulse Wave Velocity Estimation - Experimental Characterization and in-Vivo Feasibility

Authors:

H. C. Pereira, J. Maldonado, T. Pereira, M. Contente, V. Almeida, T. Pereira, J. B. Simões, J. Cardoso and C. Correia

Abstract: The use of local pulse wave velocity (PWV) as an independent risk factor for cardiovascular events and as a marker of atherosclerosis has been gained clinical relevance over the years. A novel acoustic double headed probe for non-invasive measurement of the local PWV is presented in this paper. The PWV is assessed in one single location and involves the determination of time delay between the signals acquired simultaneously by two acoustic sensors, placed ≈11 mm apart. Several tests were performed in special purposes test bench systems in order to characterize the acoustic probe (AP) regarding the existence of crosstalk between the transducers, repeatability, waveform analysis and also its time resolution. Results demonstrate the effectiveness of the AP in acquiring repeatedly the same waveform, with the possibility to measure higher PWV (14 m/s), with a relative error less than 5%, when using two uncoupled APs. In-vivo acquisitions were also carried out with the AP in the carotid artery of 17 healthy volunteers with the intention of local PWV and other hemodynamic parameters estimation, such as left ventricular ejection time (LVET). For the total of subjects’ sample, the obtained mean carotid PWV was 2.96±1.08 m/s and the LVET mean value was 288.59±21.42 ms.

Short Papers
Paper Nr: 6
Title:

Method of Multislice CT Effective Doses Estimation on the Basis of Dose Distribution Curves

Authors:

Sergey Kruchinin and Mikhail Zelikman

Abstract: Conventional dose-length product method for CT effective dose evaluation in case of multislice scanners with comparatively large X-ray beam collimation leads to underestimation of effective doses due to partly neglecting of scattered in patient body radiation. It is possible to avoid this problem taking into account “tails” of dose distribution on the length exceeds zone ±50 mm relative to the beam centre. Method of DLP evaluation on the basis of dose distribution curves with “tails” estimated on full length (±200 mm or more) is presented.

Paper Nr: 9
Title:

Towards a Dynamic Tibial Component for Postoperative Fine-tuning Adjustment of Knee Ligament Imbalance

Authors:

Andrea Collo, Shaban Almouahed, Philippe Poignet, Chafiaa Hamitouche and Eric Stindel

Abstract: During TKA surgery, a correct tibiofemoral alignment of the installed prosthesis can be effectively achieved by means of Computer-Assisted techniques. Unfortunately, the achievement of perfect ligament balance conditions still remains as unsolved problem. Any inaccuracy during the operation may degenerate and lead to prosthesis failure. Our aim is to develop an adaptive knee prosthesis, able to follow the physiological evolution of the body and, potentially, to modify its shape to fit the patient's morphological changes. In this paper, we focus on the actuation of the tibial component in order to compensate for collateral ligament imbalances. We face with severe constraints concerning the available volume, the high-accuracy level and system's solidity and biocompatibility. We discuss a model that we proposed in a previous work and we highlight its drawbacks. We consider then three possible approaches to realise the actuation: the use of a micromotor, the action of a magnetic field and the use of an external tool. After evaluating the pros and cons of each case, the micromotor approach is selected. We conclude by introducing an original design of adaptive tibial implant that we are currently developing.

Paper Nr: 10
Title:

Hemorrhage Control by Short Electrical Pulses - In Vivo Experiments

Authors:

Guy Malki, Ofer Barnea and Yossi Mandel

Abstract: An internal hemorrhagic shock is one of the leading causes of death in the battlefield and other trauma events. However the application of direct pressure, as in the treatment of an external hemorrhage, is not possible. Most common techniques to achieve vasoconstriction are through heat; yet heating causes irreversible destruction of organ tissues. Therefore, there is a need for a non-thermal based technology for hemorrhage control. The current research describes, for the first, an attempt to reduce the amount of bleeding in animal model liver injuries by using electrical pulses treatment (EPT). In the experiments, which were performed on 28 rats and 14 rabbits, a short (25µs and 50µs) EPT was applied to the treatment groups and the amount of bleeding was compared to the non-treatment (NT) groups. A reduction of 60%, 36% and 44% in blood volume, was found in the 25µs-rats, 50µs-rats and 25µs-rabbits EPT groups, respectively (P<0.001). Also, it was found that the hemorrhage control was not caused by the mechanical pressure applied by the electrodes, and there was no evidence for thermal coagulation. Further research is needed to fully expose the potential of this treatment and the modality for hemorrhage control in civilian and military settings.

Paper Nr: 11
Title:

Influence of Pipette Geometry on the Displacement Profile of Isotropic Materials used for Vocal Fold Modeling

Authors:

Sandra Weiß, Scott L. Thomson, Alexander Sutor, Stefan J. Rupitsch and Reinhard Lerch

Abstract: Due to limited access to human vocal folds, synthetic vocal folds are used to study periodic phonation. With respect to a realistic replica, the properties of the synthetic material should be to those of as real tissue. Silicone rubber is a commonly used material for vocal fold models. A suitable method to analyze the material parameters of both artificial and real vocal folds is the pipette aspiration technique. In the present study, the displacement profiles of an isotropic silicone specimen were measured with three different pipette geometries. The experimental results were compared to finite element simulations of the setup based on frequency dependent material parameters extracted from a previous study. The results demonstrate the potential of the pipette aspiration technique for material characterization and validate the determination of material parameters by means of an Inverse Method. Furthermore, a possible parameter for the classification of anisotropic materials is proposed and the suitability of the different pipette geometries for material characterization is discussed.

Paper Nr: 19
Title:

Fabrication of Straight Stainless-Steel Micro-Coils for the Use of Biodevice Components

Authors:

Toshiyuki Horiuchi, Hiroshi Sakabe, Takao Yuzawa and Daichi Yamamoto

Abstract: Fabrication method of straight micro-coils of stainless steel was investigated for applying the coils to bio-measurements. As a non-magnetizable material, SUS304 stainless steel pipes with outer and inner diameters of 100 and 60 μm were used. Specimen pipes coated with positive resist films were exposed to a violet laser beam, and helical resist patterns were delineated. The pipes masked by the helical patterns were wetly etched in electrolytic etchant composed of sodium chloride, ammonium chloride, and boric acid. As a result, micro-coils with almost homogeneous widths were successfully fabricated. The calculated spring constant was in a favourable range of 0.7-2.4 N/mm. The new micro-coil fabrication method is feasible for the use of bio-device components.

Paper Nr: 32
Title:

Custom Built Device for Spasticity Evaluation Associated to Spinal Cord Injury - A Redundant Signal to Electrogoniometer in Pendulum Test

Authors:

Renata Manzano Maria, Karina Cristina Alonso, Eliza Regina Ferreira Braga Machado de Azevedo, Renato Varoto and Alberto Cliquet Jr.

Abstract: The proposal of this project was the development of a more objective system to evaluate spasticity, dysfunction often presented by spinal cord injured people. As result, it will be possible to follow patient’s progress in moments before and after any treatment, drawing comparisons through the acquired data. One accelerometer was added to the original pendulum test, providing redundant and alternative signal to the electrogoniometer, even in critical situations. Also, tests were performed in patients during treatments, what confirmed the feasibility of the present system in this method of evaluation.

Paper Nr: 33
Title:

Development of Techniques for the Fabrication of Micro- and Nano-batteries for Biomedical Applications

Authors:

V. S. Sandeep Akkanapragada, Jacob Conner, Hayley Osman and Saibal Mitra

Abstract: Future bio-medical devices with dimensions in the nanoscale region will need independent energy sources to power them. Lithium-ion micro- and nano-batteries are excellent candidates for these power sources. Our proposed nanobattery design ensures that these batteries remain lightweight and safe with fast rechargeable times. We have used femtosecond laser for precision machining. Intense electric fields produced by the laser beam induces electrical breakdown due to avalanche ionization. For femtosecond pulses, this breakdown threshold remains fairly deterministic thereby allowing the use of femtosecond lasers for micro- and nano-machining. The nanobattery consisted of an anode, cathode and separator. The anode was made of graphite or molybdenum oxide while the cathode was made of LiCoO2. The separator was a Kapton membrane with an array of n x n holes micro- or nano-scale holes machined into it which were then filled with Li-based electrolyte. For biomedical applications these batteries must be packaged with bio compatible polymers. Initiated chemical vapor deposition is an attractive technique where polymeric films are deposited by activating a mixture of gas of monomers and initiators. This solventless technique is substrate independent and should lead to the deposition of biocompatible films that can be used to coat and package electronic devices.

Paper Nr: 35
Title:

Dynamic Calibration of Force Platforms by Means of a Parallel Robot

Authors:

E. Brau, J. Cazalilla, M. Vallés, A. Besa, A. Valera, V. Mata and A. Page

Abstract: Force platforms are the basic equipment to measure ground reaction forces and moments in biomechanical studies. So, accurate in situ calibration of force platforms is critical for ensuring the accuracy and precision of the results of experimental studies. Although there are different avaliable approaches for in situ calibration, most of the existing methods do not use realistic and repeteable force patterns to calibrate platforms. In this paper is proposed a new technique based on the use of a 3PRS parallel robot for applying a predefined dynamical load, where force patterns can be reproduced in a similar way as the used during actual experimental measures. This robot can be programmed to apply force patterns simulating the conditions of human gait, running or jumping. Calibration is performed by comparing the forces measured by the platform and the ones measured by a calibrated load cell. A new algorithm was used for correcting the sensitivity coefficients, including an estimation of errors in the orientation of the load cell. This method has been validated by means of an experiment

Paper Nr: 38
Title:

The Design of a Fully Differential Capacitive Pressure Sensor with Unbalanced Parasitic Input Capacitances in 130nm CMOS Technology

Authors:

B. T. Bradford, W. Krautschneider and D. Schroeder

Abstract: A switched capacitor amplifier for measuring absolute pressure with a micro-machined capacitive pressure sensor using correlated double sampling has been designed in 130nm CMOS technology. The switched capacitor amplifier design uses a combination of correlated double sampling, input offset cancellation, and output offset cancellation to help reject 1f noise and DC offset mismatch. A method for sizing the operational transconductance amplifier (OTA) components according to the system noise, accuracy, and bandwidth requirements is presented.

Paper Nr: 41
Title:

Investigation of the Effect of Extremely Low Frequency (ELF) Pulsed Electromagnetic Field (PEMF) on Collagenase Enzyme Kinetics

Authors:

Istiaque Ahmed, Vuk Vojisavljevic and Elena Pirogova

Abstract: In our earlier work we have discussed the design and development of an extremely low frequency (ELF) pulsed electromagnetic field (PEMF) system that produces time varying magnetic field in the range of 0.5mt to 2.5mT. 2D and 3D simulation results of the induced magnetic field produced by the system of two pairs of air core Helmholtz coils were also presented. In this study we present the modified version of the ELF PEMF system and discuss its application to study the effect of varying parametric changes of ELF PEMF radiation on Collagenase enzymes that plays a key role in the process of wound healing. The findings from this study can be used to determine the optimal characteristics of the applied ELF PEMF for wound treatment.

Paper Nr: 43
Title:

Inspired Sinewave Technique to Non-invasive Lung Function Testing - An Introduction and Update of Recent Developments

Authors:

Phi Anh Phan, Sara Ffrench-constant, Andrew Farmery and Clive E. W. Hahn

Abstract: Inspired Sinewave is a novel technique to measure dead space, alveolar volume, and pulmonary blood flow noninvasively. In this paper, we describe a brief introduction to the principle of the technique, which involves forcing inspired concentrations to oscillate sinusoidally and measuring responding expired concentrations. Then, we give some updates to the recent developments of the device. These include accuracy and robustness studies of the device on bench lungs and volunteers, and study of lung volume change from sitting to supine. The success of these studies is a big step forward to make this novel device a useful clinical tool. The paper concludes with a description of future work.

Paper Nr: 44
Title:

Analysis of Fault Injection in Implantable Capacitive Blood-pressure Sensors

Authors:

J. A. Miguel, Y. Lechuga and M. Martinez

Abstract: This work explores the fault injection problem in the particular case of an implantable capacitive micro-electromechanical pressure sensor for blood-flow measurement applied to the detection of in-stent restenosis. In order to develop a MEMS testing method for this sensor and its related electronic circuitry, an accurate and realistic fault model is essential. A behavioural description of the equivalent capacitance in the fault-free case can be obtained from the analytical and numerical solutions of the deflection of a circular diaphragm under a uniformly distributed pressure. However, the deflection problem for faulty conditions due to, for example, contamination-based defects or partially released structures must be solved and modelled using finite-element analysis.

Paper Nr: 45
Title:

Vibration Diagnostic Probe for Discogenic Pain Due to a Fissure in an Annulus Fibrosus

Authors:

Jae-Cheon Kim, Giseok Kang, Hyoung-Ihl Kim and Jong-Hyun Lee

Abstract: Discogenic pain is the most common cause of chronic low back pain, accounting for 39% of causes. One possible diagnostic method to determine the cause of discogenic pain is provocative discography. However, this method is not available to patients with severe fissures due to degenerative disc disease. In this paper, we present a diagnostic probe in which plastic optical fiber (POF), which is located in a hole in the flexible tube of the probe, can be steered to the vicinity of fissures in the annulus fibrosus. Then, a linear motor placed inside the grip generates a minute axial vibration of the POF tip, which irritates the tiny pain nerves located near fissures. The intensity of the pain thus generated is used as a guideline to determine the level of discogenic disease. The frequency and amplitude of the vibration discography ranged from 2.5 Hz to 5.7 Hz and 1.5 mm to 3.4 mm, respectively. The applicability of the designed probe was successfully confirmed by testing the modified intradiscal microprobe in an ex vivo animal experiment.

Paper Nr: 56
Title:

A Preliminary Study of Non-intrusive Blood Pressure Monitoring using Portable Device

Authors:

Hanbyul Kim, Hongji Lee, Hyunjae Baek, Wonkyu Lee, Jungsu Lee and Kwangsuk Park

Abstract: Novel blood pressure (BP) monitoring device focused on portability was studied preliminarily. Electrocardiogram (ECG) and photoplethysmogram (PPG) was measured and pulse arrival time (PAT) was computed from these signals. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) showed a clear correlation with PAT. BP estimation model was constructed based on this result and verified by means of leave-one-out cross-validation (LOOCV). Estimated SBP, DBP were involved in two standards of means of original data. This device is expected to be useful to the people who want to monitor BP at any time and space.

Paper Nr: 57
Title:

Towards Assistive Robotics for Home Rehabilitation

Authors:

Elsa Andrea Kirchner, Jan Christian Albiez, Anett Seeland, Mathias Jordan and Frank Kirchner

Abstract: In this paper, we want to point out the possibilities that arise from the latest advances in robotic exoskeleton design and control. We show that approaches of artificial intelligence research and robotics that integrate psychophysiological data analysis offer the possibility to assist disabled people in their everyday lives. Thus, continuous long term rehabilitation training and daily support can be provided in the future to help them to regain motor functions. We outline a possible scenario for fully embedded home rehabilitation and its components. The presented work further investigates two challenges of the application of such a system in more detail: (i) improvement of the interaction between the patient and the supporting interface and (ii) enhancement of reliability of predictions made about the patients intention. In the experimental part we demonstrate that the exoskeleton control can compensate for gravitational loads, imposed by the device itself. Further, we present results that show that movement onset prediction can be made based on different psychophysiological measures, and can be improved with respect to their reliability.

Paper Nr: 60
Title:

Modeling Workflow for Study of Functional Electrical Stimulation in Peripheral Nerves

Authors:

Fábio Rodrigues, Marian Bartek and Paulo Mendes

Abstract: Urinary dysfunctions are among the most devastating consequences of spinal cord injuries (SCI). Neurostimulation of intact sacral nerve roots innervating bladder is potentially a good alternative to the treatments using drugs and catheterization. A finer control over the electrical stimulation of sacral roots can be an enabling technology for developing advanced neurostimulation matching the patient needs. In this paper a modeling workflow to study axon behaviour in sacral nerve roots is presented. Simulation results show that the width and the amplitude of the stimulation electric pulses can be tuned to selectively recruit axons in sacral roots. A selective recruitment of axons innervating bladder is shown to be possible for pulse widths above 9 ms.

Paper Nr: 66
Title:

Improved ROI Algorithm for Compressing Medical Images

Authors:

Mohamed Nagy Saad and Ahmed Hisham Kandil

Abstract: The digital medical images have become an essential part of the electronic patient record. These images may be used for screening, diagnosis, treatment and educational purposes. These images have to be stored, archived, retrieved, and transmitted. Compression techniques are extremely useful when considering large quantities of these images. In this paper, four compression techniques are applied on three medical image modalities. The compression techniques are either lossless or lossy techniques. The applied lossless techniques are Huffman and Arithmetic. The applied lossy techniques are Discrete Cosine Transform (DCT) and Wavelet. The modalities are Ultrasound (US), Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). The observed parameters are both the compression ratio (CR) and total compression time (TCT) (compression time + decompression time). The target is to maximize the CR while preserving images’ information using the best compression technique. The maximum accepted CR for each image is chosen by three experts. The last enhancement is done by isolating the region of interest (ROI) in the image then applying the compression procedure. Applying the ROI technique on the studied cases by the experts gave promising results.

Paper Nr: 67
Title:

A Wireless EEG Acquisition Platform based on Embedded Systems

Authors:

F. Pinho, J. H. Correia and N. S. Dias

Abstract: This paper proposes a wireless EEG acquisition platform based on Open Multimedia Architecture Platform (OMAP) embedded system. A high-impedance active dry electrode was tested for improving the scalp-electrode interface. It was used the sigma-delta ADS1298 analog-to-digital converter, and developed a “kernelspace” character driver to manage the communications between the converter unit and the OMAP’s ARM core. The acquired EEG signal data is processed by a “userspace” application, which accesses the driver’s memory, saves the data to a SD-card and transmits them through a wireless TCP/IP-socket to a PC. The electrodes were tested through the alpha wave replacement phenomenon. The experimental results presented the expected alpha rhythm (8-13 Hz) reactiveness to the eyes opening task. The driver spends about 725 μs to acquire and store the data samples. The application takes about 244 μs to get the data from the driver and 1.4 ms to save it in the SD-card. A WiFi throughput of 12.8Mbps was measured which results in a transmission time of 5 ms for 512 kb of data. The embedded system consumes about 200 mAh when wireless off and 400 mAh when it is on. The system exhibits a reliable performance to record EEG signals and transmit them wirelessly. Besides the microcontroller-based architectures, the proposed platform demonstrates that powerful ARM processors running embedded operating systems can be programmed with real-time constrains at the kernel level in order to control hardware, while maintaining their parallel processing abilities in high level software applications.

Paper Nr: 69
Title:

Carbon Electrode based Urea Sensor - Modification of Graphite and New Polymeric Carriers for Enzyme Immobilization

Authors:

Julija Razumiene, Ieva Sakinyte, Tatjana Kochane, Sandra Maciulyte, Antanas Straksys, Saulute Budriene and Jurgis Barkauskas

Abstract: The amperometric biosensor for urea determination was designed based on the electrochemical oxidation of urea decomposition products produced by urease. The enzyme electrode, made of a specially developed modified graphite (MG) paste, was produced by covering the electrode surface with new polymeric carriers poly(urethane-urea) (PUU) microparticles containing immobilized urease from Canavalia ensiformis (E.C. 3.5.1.5.).

Paper Nr: 72
Title:

Ex-vivo Platelet Activation using Electric Pulse Stimulation

Authors:

Nicole LaPlante, V. Bogdan Neculaes, Brian D. Lee, Andrew S. Torres, Kenneth Conway, Steve Klopman and Antonio Caiafa

Abstract: Activated platelet rich plasma (PRP), also known as platelet gel, is an encouraging autologous cell therapy with numerous applications in areas including: wound healing, haemostasis and wound infection control. Activation of PRP using electric pulse stimulation is a promising alternative to activation via biologics such as bovine thrombin. By removing the need for biologics, it is possible to deliver a cost-effective, fast, truly autologous platelet gel option. In this position paper, we describe parameters for effective ex-vivo release of several growth factors from human platelets in PRP using electric field pulses with the duration of hundreds of nanoseconds. Growth factor release levels with nanosecond pulse electric fields seem at the same level or higher compared to bovine thrombin, the standard platelet activator used in clinical practice. These findings suggest that electric pulse stimulation has the potential to become not only a viable alternative to biochemical platelet activators, but to actually enhance the desired in vivo biological effects, such as wound healing.

Paper Nr: 74
Title:

Cellular Factories - Emerging Technologies for Fabrication of Nanomedicines?

Authors:

V. Ramos, X. Turon and S. Borros

Abstract: The development of innovative nanomedicines requires the implementation of new biocompatible materials and their efficient assembly into defined nanostructures. Complex and costly synthesis of these materials can be coped with biological fabrication using microorganism factories, recombinant DNA and metabolic engineering. Modern bioprocess technologies may have the key for the implementation of tomorrow’s nanomedicines. This paper specifically focuses on the current state of the art of nanopharmaceuticals and their future perspectives.

Paper Nr: 75
Title:

Prototype and Graphical Interface for Selective Exhaled Air Acquisition

Authors:

Fábio Dias, José Alves, Fábio Januário, José Luís Ferreira and Valentina Vassilenko

Abstract: The recent advances in technology and detection methods, as well as its economic viability have pointed the analysis of exhaled breath as a promising tool for medical diagnosis or therapy monitoring. Since the concentration of the most Volatile Organic Compounds (VOCs) present in the exhaled breath is very low (ppbv – pptv range) it is important to have a selective sampling system for alveolar air. In this work we present the design and instrumentation of a prototype that allows real time monitoring of the breathing cycle and automatically decide the correct moment for acquisition and channel the acquired sample to the Ion Mobility Spectrometer with Multi-Capillary Column pre-separation (MCC-IMS). The prototype is composed by a flow meter, signal packaging circuits and a flow commuting circuit (three-way valve). Two graphical interfaces were also developed to help controlling the whole process of acquisition making it easy, quick and reliable.

Paper Nr: 76
Title:

Instrumental Tools for Express Analysis of Lacrimal Fluids

Authors:

Valentina Vassilenko, Mónica Silva, Ricardo Alves and João O’Neill

Abstract: Analysis of lacrimal fluid is under attention of scientists and physicians as an open “window” for non-invasive assessment to relevant information about the health status. In the present work we propose an innovative method for the analysis of volatile metabolites present in the lacrimal fluid by non-invasive, fast and inexpensive technique: Ion Mobility Spectrometry coupled to a Multi-Capillary Column (MCC-IMS). Experimental protocol for lacrimal fluid collection and its further analysis by MCC-IMS was developed. For the first time this technology was used for the analysis of tears from healthy and diabetic person for a “proof of concept” purpose. Obtained experimental result showed that proposed method is suitable for the sensitive in-situ express analysis of Volatile Organic Compounds (VOCs) from lacrimal fluid and have a promising diagnostic potential.

Paper Nr: 79
Title:

Multi-purpose Electrostimulator Software

Authors:

Nuno Costa, Tiago Araujo, Neuza Nunes and Hugo Gamboa

Abstract: Nowadays, most of the software for electrostimulation is made with specific purposes, and in some cases they have complicated user interfaces and large, bulky designs that deter usability and acceptability. A novel Human Computer Interaction framework was developed enabling the end user to configure and control an electrostimulator, surpassing the specific use of several electrostimulator software. In the configuration the user is able to compile different types of electrical impulses (modes) in a temporal session, and this session can be actuated in the control. To help the user in creating any type of protocol (session) we devised three standard impulse generator (rectangular, sin and triangular) and a new way of creating electrical impulses by drawing, then fitting this data and process it with a mathematical algorithm for finding simple equations to describe the data. With it, the user has the possibility to choose the best equation that fits the draw and store it mathematically structured, thus adding not only a draw editor, but also an equation editor. Therefore, we provide a tool for clinical, sports and investigation where the user is free to produce their own protocols by sequentially compile electrical impulses.

Posters
Paper Nr: 15
Title:

Optical Fiber Probe as a Source of Errors and Uncertainty in Measurements for Optical Noninvasive Diagnostic Devices and Techniques

Authors:

Dmitry Rogatkin and Oxana Smirnova

Abstract: Over the last 10-15 years a large amount of methods and devices of noninvasive medical spectrophotometry including such techniques as in vivo Laser Fluorescent Diagnostics, Tissues Reflectance Oximetry, Laser Doppler Flowmetry, etc. has been developed and involved in a real clinical practice. In that number several problems of accuracy and reproducibility of clinical diagnostic results have been under discussion as well. But systematic metrological research in this field is still unknown. What dispersions and errors in diagnostic data can be estimated if measurements will be executed on the same object several times, by several doctors with different qualifications or using several devices from both the same and a different manufacturer? In this paper some results of the complex study of errors and uncertainties in diagnostic data caused by using an optical multi-fibers probe are presented. Dispersion and errors up to a level of +/-36,3% for the average registered values were discovered. It is shown that the interactive component of errors caused by interaction of the probe and a surveyed object gives the main contribution to the total uncertainty in diagnostic data.

Paper Nr: 16
Title:

Preparation of a PLGA/Calcium Silicate Composite with Gradient Pore Structure

Authors:

Bong-Kyu Choi, Suk Young Kim and Sang-Hoon Rhee

Abstract: The PLGA/SiO2-CaO composite, which have a gradient pore structure, was newly prepared by the expansion of carbon dioxide gas in the PLGA matrix. The bioactive SiO2-CaO particles were made by a sol-gel method from tetraethyl orthosilicate and calcium nitrate tetrahydrate under acidic condition followed by the heat treatment at 600oC for 2 h. The PLGA/SiO2-CaO composite was then prepared by a solvent casting using chloroform as solvent. The composite was loaded into the high pressure chamber and then carbon dioxide gas was introduced achieving a final pressure of 10 MPa. After 3 days, the gas was released quickly and the gradient pore structure was developed. The samples were observed by FE-SEM and its bioactivity was tested in simulated body fluid.

Paper Nr: 17
Title:

Using Smartphone Bases Biodevices for Analyzing Physiological, Psychological and Behavioral User’s Habits

Authors:

Federico Guede Fernández, Marc Pous Solà, Miguel Ángel García González, Lluís Capdevila Ortís, Juan Ramos Castro and Mireya Fernández Chimeno

Abstract: As a consequence of increasing life expectancy, the promotion of lifestyles that allow aging wellbeing guarantees has acquired great importance in the developed countries. However, the adherence to healthy behaviors in young and adult people remains as a big problem in the community health field. The development of markers of adherence to healthy lifestyles and the evaluation its effectiveness is a goal of many research groups. This paper presents a system for analyzing physiological, psychological and behavioural user’s habits using a smartphone and externals biodevices. We use an Android smartphone with an internal tri-axial accelerometer and GPS to monitor physical activity. The smartphone is connected via Bluetooth to a respiratory sensor for breath monitoring. In addition, Android application contains psychological questionnaires to analyze user’s mood state and at the same, social interaction is analyzed tracking phone usage and user’s social network. Finally, the collected information is sent to a remote server for a long-term processing.

Paper Nr: 18
Title:

An Electrocardiogram (ECG) Signal Processing Algorithm for Heart Parameters Estimation based on QRS Complex Detection

Authors:

Lorenzo Piazzo, Francesco Delli Priscoli, Guido Oddi, Donato Macone and Silvano Mignanti

Abstract: This paper presents an algorithm able to estimate heartbeat parameters, based on a QRS complex detection. The proposed algorithm demonstrates to be able to recognize heartbeat parameters even in highly noisy situations, i.e. where the ECG signal is extremely disturbed. Furthermore the algorithm was tested on real ECG signals generated by a so called Wearable Unit, a complex bio-signals sensor being developed by STMicroelectronics within the Bravehealth ICT FP7 EU funded project.

Paper Nr: 25
Title:

Quantitative Analysis of the Effect of Prolonged Mechanical Ventilation on Capnographic Indices

Authors:

Carmen Caroline Rasera, Pedro Miguel Gewehr and Adriana Maria T. Domingues

Abstract: The monitoring of carbon dioxide pressure through Capnography has been clinically used as a continuous and non-invasive measurement of alveolar ventilation. The patients with lung disease, respiratory and hemodynamic instability and when in mechanical ventilation have a significant alteration in the waveform of the capnogram. In this study, quantitative analysis between capnographic indices of the patients under prolonged mechanical ventilation were obtained and compared to waveforms of spontaneously breathing patients. The measurements were performed at the 10th day of invasive mechanical ventilation and 48 hours after tracheal extubation, totalling 52 capnographic curves. PaCO2 and PetCO2 measurements maintained a significant correlation in spontaneously breathing patients (r2 = 0.97, p<0.001) and a weak correlation in patients during prolonged mechanical ventilation (r2 = 0.86). Four waveform parameters (intermediate slope, alpha angle, beta angle and area ratio) were identified as altered. These altered parameters can provide guidance to physicians about the physiological interpretation of capnograms and clinical decision. Proper interpretation of the capnogram can alert a clinician to important changes in mechanical ventilatory parameters in order to obtain a capnographic wave closest to normal thereby improving the lung function of patients.

Paper Nr: 31
Title:

Algorithmic Surface Extraction from MRI Data - Modelling the Human Vocal Tract

Authors:

D. Aalto, J. Helle, A. Huhtala, A. Kivelä, J. Malinen, J. Saunavaara and T. Ronkka

Abstract: A procedure for the vectorisation and feature extraction of the human vocal tract is proposed. The raw data is obtained by high resolution 3D MRI. Because the amount of manual work in the data processing has been minimised, large datasets can be treated. The vectorised data can be used for both numerical as well as physical modelling of the vocal tract biophysics, including speech and applications in medicine.

Paper Nr: 50
Title:

BITtalino: A Biosignal Acquisition System based on the Arduino

Authors:

Ana Priscila Alves, Hugo Silva, André Lourenço and Ana Fred

Abstract: Our work presents a low-cost biosignal acquisition system, BITalino, based on the Arduino hardware platform; both the hardware and software components are detailed, together with experimental evaluation. This system was designed to be integrated in a biometric platform based on Electrocardiographic (ECG) signals, that will be used for identity recognition. The experimental evaluation revealed that this system is not only capable of ECG signal acquisition, for biometric purposes, but it can also be used as a generic platform for other biomedical applications, greatly extending its applicability. In this paper we describe the proposed platform, with special emphasis on the design principles and functionality. Future work will focus on further developing our hardware, targeting its integration in a prototype system for ECG-based biometric recognition.

Paper Nr: 59
Title:

Modeling H2 Adsorption Processes at SnO2 Nanowire Surfaces - Parameter Estimation and Simulation

Authors:

G. Tulzer, S. Baumgartner, E. Brunet, G. C. Mutinati, S. Steinhauer, A. Köck and C. Heitzinger

Abstract: Metal-oxide gas sensors are advantageous for various purposes due to their physical and chemical as well as electrical properties. However, a lack of selectivity remains the central issue in this field. A quantitative understanding of the processes at the semiconductor surface is crucial to overcome these difficulties. In this work, we determine numerical values for the parameters governing the interaction of H2 with the device to obtain quantitative information regarding the influence of the atmosphere on the sensor. With the computed values, simulations regarding the surface charge can be performed to understand the sensor behavior under different ambient conditions.

Paper Nr: 62
Title:

Utilizing a Mobile Electrode (PEN) for Functional Electrical Stimulation (FES) to Treat Facial Paralysis Caused by a Brain Injury - A Case Study

Authors:

Fabiana S. B. Perez, Adson Ferreira da Rocha, Karla de Castro Cardoso, Hellen Orlando Veloso and Inez Janaina de Lima Amaral

Abstract: This research is a case study that evaluated the therapeutic efficacy of Functional Electrical Stimulation (FES) associated with the method of Proprioceptive Neuromuscular Facilitation (PNF) in a patient with central facial paralysis caused by brain damage resulting from brain anoxia. The treatment involved the application of Orofacial Regulation Therapy, associated with physical therapy using a pen-shaped electrode whith an FES current. The treatment was administered for a period of one year and involved two weekly 15 minute sessions. The stimuli were performed with modulated current at a frequency of 60 hertz, pulse width of 300 miliseconds, rise of four (4) seconds, decay of four (4) seconds, time ON of one (1) second, time OFF of five (5) seconds, in trapezoidal pulses (forming a mini cycle of 14 seconds with 30 pulses) at an intensity level measured according to the patient’s sensitivity, associated with the PNF method. The mobile pen-shaped electrode was positioned at precise points on the paralyzed muscles of the face, and the fixed-electrode was positioned on the Deltoid muscle. There was satisfactory rehabilitation of muscles in the left hemiface and acquired improvement in the oral consumption of the bolus. The symmetry of the face was also enhanced, along with facial expressions and connotation measuring four (4) on the Chevalier scale.

Paper Nr: 63
Title:

Comparison of Energy Harvesting Techniques for Wearable Activity Monitoring Devices

Authors:

Ana Cimpian, Bastien Granier, Gearóid Ó Laighin and Maeve Duffy

Abstract: Piezoelectric and electromagnetic generation are the two most common energy harvesting techniques. The aim of this paper is to present a comparison of the two techniques in terms of powering a wearable monitoring device. An electromagnetic generator and a piezoelectric system are proposed to power an activity monitoring device located in the shoe.

Paper Nr: 64
Title:

BioSigMA - Bio Signal Monitoring Application

Authors:

Daniel Ferreira and Gil Gonçalves

Abstract: The aging of the population causes an increased prevalence of chronic diseases, such as cardiovascular disease (which is the leading cause of death in developed countries) and dementia. Because of the high morbidity and mortality rates associated with this group of diseases, it is necessary to continuously monitor the vital signs of people at risk. Nowadays this monitoring is carried out by a Holter monitor, which acquires electrocardiogram data for a long period of time, so that it can be analyzed later. However, this is not a real-time monitoring. There is another type of monitor, which stores the data and communicates with a remote server, allowing realtime continuous monitoring. The latter system requires a specific platform and, as result, the patients have to adapt to yet another device in their daily activities. Information and communication technologies (ICT) have had a remarkable role in the management of health care distribution and social work, and can be applied on daily monitoring of patients, providing a timely opportunity for medical staff to intervene. In the ICT field we have witnessed the rise of smartphones as a gadget with great mobility, connectivity and processing capacities. They are the ideal device to take patient monitoring to the next level, replacing the need for specific platforms for each type of monitoring, and facilitating the daily lives of patients. This ability of smartphones becomes more and more apparent with the increasing number in new medical applications that profit from its characteristics. Therefore, our goal is to create an application for smartphones which takes advantage of the portability and processing capacities of smartphones to assess cardiac function, using bio signals captured by a device with bluetooth interface and the sensors on the smartphone, and subsequent processing with a medical telemetry system.

Paper Nr: 65
Title:

Reverse Translational Research - How Clinical Trials on Fluorescence Imaging for Vocal Cord Cancer Fuels Fundamental Research

Authors:

Olivier Gaiffe, Christian Pieralli, Laurent Tavernier, Lionel Pazart and Bruno Wacogne

Abstract: Translational research consists in translating fundamental research results as closely as possible to patients. Researchers sometimes underestimate these studies because it is thought that, although essential for setting up new investigation tools, they do not deepen fundamental knowledge. However, users face specific difficulties due to the variability of the biological systems under study. Variability is easily understood from one patient to another, but there is also variability in a single patient whose metabolism evolves together with therapeutic actions. Results obtained in translational research often depend on this variability, and new questions and scientific obstacles arise when research is applied to the real world. In order to address these new challenges, reverse translational research is required. Fundamental research is fuelled by the results of translational research. In this position paper, we consider vocal cord fluorescence imaging as an example of bi-directional translational research. First, we briefly recall the basics of fluorescence imaging, and we explain why commercial fluorescence systems lead to variable estimations of their efficiency by end-users. Second, we describe solutions intended to improve fluorescence techniques. This position paper will then make conclusions.

Paper Nr: 71
Title:

Finger Joint Characterization from X-Ray Images for Rheumatoid Arthritis Assessment

Authors:

Joan M. Núñez, Débora Gil and Fernando Vilariño

Abstract: In this study we propose amodular systemfor automatic rheumatoid arthritis assessment which provides a joint space width measure. A hand joint model is proposed based on the accurate analysis of a X-ray finger joint image sample set. This model shows that the sclerosis and the lower bone are the main necessary features in order to perform a proper finger joint characterization. We propose sclerosis and lower bone detection methods as well as the experimental setup necessary for its performance assessment. Our characterization is used to propose and compute a joint space width score which is shown to be related to the different degrees of arthritis. This assertion is verified by comparing our proposed score with Sharp Van der Heijde score, confirming that the lower our score is the more advanced is the patient affection.

Paper Nr: 73
Title:

Pure-tone Audiogram - Measuring Auditory Sensitivity over the Age

Authors:

João Paulo Teixeira and Paula Odete Fernandes

Abstract: In this study a pure tone audiogram was developed under the Matlab® mathematical software. Audiogram measurements were performed to 35 subjects belonging to the female and male and aged between 10 and 88 years old. Some of the subjects with more advanced age had hearing problems over the course of age, however, none of them was carrying any type of hearing aid. The threshold of the Sound Pressure Level (SPL) was recorded under 12 pure tones between 125 Hz and 15 kHz. The developed pure-tone audiogram confirmed its ability to produce auditory brainstem responses (ABRs). Statistical analysis of the SPL threshold shows no differences between genders and confirms the correlation between age and loss of sensitivity, more accentuated for higher frequency tones. A strong loss of sensitivity was observed after the decade of 60 years old.