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  • 1.
    Aare, Magnus
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Evaluation of head response to ballistic helmet impacts, using FEM2003Konferensbidrag (Refereegranskat)
  • 2.
    Aare, Magnus
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Halldin, Peter
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Proposed global injury thresholds for oblique helmet impacts2003Konferensbidrag (Refereegranskat)
  • 3.
    Abtahi, Farhad
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Towards Heart Rate Variability Tools in P-Health: Pervasive, Preventive, Predictive and Personalized2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Hjärtfrekvensvariabilitet (HRV) har senaste tiden rönt en hel del uppmärksamhet och flera teknikerför analys av HRV i tids- resp. frekvensområdet samt medels icke-linjära metoder har utvecklats.Det har visats att HRV kan användas för att övervaka det autonoma nervsystemet (ANS) blandannat för att upptäcka särskilt vagala störningar inom ANS. Minskad HRV förknippas med flerasjukdomar såsom diabetes, reumatoid artrit, depression, kronisk hjärtsjukdom och har ävenföreslagits som prediktor för dålig prognos och plötslig hjärtdöd. HRV är dock ännu inte allmäntaccepterat som ett kliniskt verktyg utan används främst inom forskning. Framsteg inomneuroimmunitetsområdet med ökad förståelse för sambandet mellan nerv- och immunsystem, haröppnat en nytt potentiell område för HRV-applikationer. Ett exempel är när systemiskinflammationoch autoimmun sjukdom primärt orsakas av låg vagal aktivitet, vilket kan upptäckas ochprognostiseras via minskad HRV. Denna avhandling är resultatet av flera tekniska utvecklingsstegoch explorativ forskning där HRV tillämpas i syfte att utveckla ett prognostiskt diagnostiskt verktygmed förebyggande potential. Huvudsyften har varit: 1) att utveckla ett prisvärt verktyg för eneffektiv och enkel analys av HRV 2) att studera sambandet mellan HRV och pro-inflammatoriskamarkörer och därigenom potentiellt återspegla graden av aktivitet i den kolinergaantiinflammatoriska effektorvägen 3) att utveckla datorprogramvara för ett biologisktåterkopplingssystem där individen med egen träning ökar sin vagala aktivitet vilket sedanåterspeglas i en ökad HRV. I denna sammanläggningsavhandling finns utförlig beskrivning av varjeingående studies metod och resultat artikar I-VI. I ramberättelsen presenteras en kortsammanfattning av metoder och resultat, grupperade efter ämne och sammanhang.Sammanfattningsvis visar resultaten att de utvecklade verktygen adekvat registrerar och analyserarHRV korrekt enkelt , samt att HRV kan påverkas av spel-träning. HRV i framtaget koncept harpotential att användas som ett skarpt prognostiskt verktyg, inte bara för traditionell vård med fokuspå sjukdom, utan också inom friskvård. Framtagna verktyg möjliggör tidig upptäckt av minskadHRV, snabb intervention och prevention. Spelifiering med seriöst spelande utgör en potentiellplattform som motiverar en träningsrutin och som genom återkoppling kan öka HRV och därmedvälmåendet.

  • 4. Abtahi, Farhad
    et al.
    Forsman, Mikael
    Diaz-Olivazrez, Jose A.
    KTH, Skolan för teknik och hälsa (STH).
    Yang, Liyun
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi.
    Lu, Ke
    KTH, Skolan för teknik och hälsa (STH).
    Eklund, Jörgen
    KTH, Skolan för teknik och hälsa (STH).
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH).
    Seoane, Fernando
    Teriö, Heikki
    Mediavilla Martinez, Cesar
    Aso, Santiago
    Tiemann, Christian
    Big Data & Wearable Sensors Ensuring Safety and Health @Work2017Ingår i: GLOBAL HEALTH 2017, The Sixth International Conference on Global Health Challenges, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    —Work-related injuries and disorders constitute a major burden and cost for employers, society in general and workers in particular. We@Work is a project that aims to develop an integrated solution for promoting and supporting a safe and healthy working life by combining wearable technologies, Big Data analytics, ergonomics, and information and communication technologies. The We@Work solution aims to support the worker and employer to ensure a healthy working life through pervasive monitoring for early warnings, prompt detection of capacity-loss and accurate risk assessments at workplace as well as self-management of a healthy working life. A multiservice platform will allow unobtrusive data collection at workplaces. Big Data analytics will provide real-time information useful to prevent work injuries and support healthy working life

  • 5.
    Abtahi, Farhad
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. Karolinska Institutet, Sweden.
    Hilderman, Marie
    Bruchfeld, Annette
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. University of Borås, Sweden.
    Janerot-Sjöberg, Birgitta
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinsk bildteknik. Karolinska Institutet, Sweden.
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. Karolinska Institutet, Sweden.
    Pro-inflammatory Blood Markers and Heart Rate Variability in Apnoea as a Reflection of Basal Vagal ToneManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Pro-inflammatory cytokines play a crucial role in inflammatory response, which istightly regulated by the nervous system to avoid the damage caused by inflammation. There isevidence for a cholinergic anti-inflammatory pathway that includes afferent and efferent vagalnerves that sense the inflammation and stimulate the anti-inflammatory response. Non-functionalanti-inflammatory response might lead to excessive and chronic inflammation e.g., rheumatoidarthritis (RA), inflammatory bowel disease (IBD), and poor outcome. Heart rate variability(HRV) has been proposed as a potential tool to monitor the level of anti-inflammatory activitythrough the monitoring of vagal activity. In this paper, the association of pro-inflammatorymarkers with HRV indices is evaluated. We used a database called “Heart Biomarker Evaluationin Apnea Treatment (HeartBEAT)” that consists of 6±2 hours of Electrocardiogram (ECG)recordings during nocturnal sleep from 318 patients at baseline and 301of them at 3 monthsfollow-up. HRV indices are calculated from ECG recordings of 5-360 minutes. The results showa statistically significant correlation between heart rate (HR) and pro-inflammatory cytokines,independent of duration of ECG analysis. HRV indices e.g., standard deviation of all RRintervals (SDNN) show an inverse relation to the pro-inflammatory cytokines. Longer ECGrecordings show a higher potential to reflect the level of anti-inflammatory response. In light oftheories for the cholinergic anti-inflammatory pathway, a combination of HR and HRV as areflection of basal vagal activity might be a potential prognostic tool for interventional guidance.

  • 6.
    Abtahi, Farhad
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Löfgren, Nils
    Elimination of ECG Artefacts in Foetal EEG Using Ensemble Average Subtraction and Wavelet Denoising Methods: A Simulation2014Ingår i: XIII Mediterranean Conference on Medical and Biological Engineering and Computing 2013, Springer, 2014, s. 551-554Konferensbidrag (Refereegranskat)
    Abstract [en]

    Biological signals recorded from surface electrodes contain interference from other signals which are not desired and should be considered as noise. Heart activity is especially present in EEG and EMG recordings as a noise. In this work, two ECG elimination methods are implemented; ensemble average subtraction (EAS) and wavelet denoising methods. Comparison of these methods has been done by use of simulated signals achieved by adding ECG to neonates EEG. The result shows successful elimination of ECG artifacts by using both methods. In general EAS method which remove estimate of all ECG components from signal is more trustable but it is also harder for implementation due to sensitivity to noise. It is also concluded that EAS behaves like a high-pass filter while wavelet denoising method acts as low-pass filter and hence the choice of one method depends on application.

  • 7.
    Akay, Altug
    KTH, Skolan för teknik och hälsa (STH), Hälso- och systemvetenskap, Systemsäkerhet och organisation.
    A Novel Method to Intelligently Mine Social Media to Assess Consumer Sentiment of Pharmaceutical Drugs2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis focuses on the development of novel data mining techniques that convert user interactions in social media networks into readable data that would benefit users, companies, and governments. The readable data can either warn of dangerous side effects of pharmaceutical drugs or improve intervention strategies. A weighted model enabled us to represent user activity in the network, that allowed us to reflect user sentiment of a pharmaceutical drug and/or service. The result is an accurate representation of user sentiment. This approach, when modified for specific diseases, drugs, and services, can enable rapid user feedback that can be converted into rapid responses from consumers to industry and government to withdraw possibly dangerous drugs and services from the market or improve said drugs and services.

    Our approach monitors social media networks in real-time, enabling government and industry to rapidly respond to consumer sentiment of pharmaceutical drugs and services.

  • 8.
    Alvarez, Victor
    et al.
    KTH.
    Halldin, Peter
    KTH.
    Kleiven, Svein
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Neuronik.
    The Influence of Neck Muscle Tonus and Posture on Brain Tissue Strain in Pedestrian Head Impacts2014Ingår i: 58th SAE Stapp Car Crash Conference, STAPP 2014, Vol. 58Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pedestrians are one of the least protected groups in urban traffic and frequently suffer fatal head injuries. An important boundary condition for the head is the cervical spine, and it has previously been demonstrated that neck muscle activation is important for head kinematics during inertial loading. It has also been shown in a recent numerical study that a tensed neck musculature also has some influence on head kinematics during a pedestrian impact situation. The aim of this study was to analyze the influence on head kinematics and injury metrics during the isolated time of head impact by comparing a pedestrian with relaxed neck and a pedestrian with increased tonus. The human body Finite Element model THUMS Version 1.4 was connected to head and neck models developed at KTH and used in pedestrian-to-vehicle impact simulations with a generalized hood, so that the head would impact a surface with an identical impact response in all simulations. In order to isolate the influence of muscle tonus, the model was activated shortly before head impact so the head would have the same initial position prior to impact among different tonus. A symmetric and asymmetric muscle activation scheme that used high level of activation was used in order to create two extremes to investigate. It was found that for the muscle tones used in this study, the influence on the strain in the brain was very minor, in general about 1-14% change. A relatively large increase was observed in a secondary peak in maximum strains in only one of the simulated cases. 

  • 9.
    Angelopoulos, Angelos
    et al.
    -.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    -.
    Danielsson, Mats
    KTH, Tidigare Institutioner, Fysik.
    K0⇋ K̄0 transitions monitored by strong interactions: a new determination of the K L–K S mass difference2001Ingår i: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 503, nr 1, s. 49-57Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The CPLEAR set-up (modified) has been used to determine the KL–KS mass difference by a method where neutral-kaon strangeness oscillations are monitored through kaon strong interactions, rather than semileptonic decays, thus requiring no assumptions on CPT invariance for the decay amplitudes. The result, Δm=(0.5343±0.0063stat±0.0025syst)×1010ℏ/s, provides a valuable input for CPT tests.

  • 10.
    Arousell, Anna
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Engdahl, Ylva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Can Surface Scanning Improve the Workflow of Elekta Linac Treatments?2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The aim of the project was to compare the workflow for an Elekta Linac with and without the surfacescanning system Catalyst and describe pros and cons with both workflows. The findings in the reportcan be used as decision support in development of Elekta products and workflow improvements.

    The method for the project was to do interviews, observations and time measurements at Södersjukhuset(not using Catalyst) and Sundsvalls sjukhus (using Catalyst). The workflows were graded in an as-sessment protocol covering time efficiency, comfort, noise, resources, reliability, cost, dosage and sideeffects. Different workflow scenarios were simulated in AnyLogic.

    The result of the project was that, according to our protocol, the workflow with Catalyst was ratedhigher than without it. The simulations in Anylogic showed that minimizing gaps in the treatment sched-ule generated the same number of patients treated per day, if the positioning could not be done faster.The simulations also showed that removing position verification with cone beam computer tomography(CBCT), an imaging system which is used in addition to the Catalyst system, would increase the numberof treated patients with approximately 33%.

    The conclusion was that there were no great differences in time efficiency between the workflows. How-ever, considering the higher reliability and comfort for the patient, optical surface scanning can improvethe positioning for Elekta Linac and is therefore worth implementing. Minimizing treatment gaps wouldnot improve the workflow. Removing the use of CBCT would increase the number of treated patientsper day.

  • 11.
    Askfors, Ylva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Hälsoinformatik.
    Samverkan för innovation: En fallstudie av mötet mellan akademi, industri och sjukvård2018Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [sv]

    Samverkan kan leda till innovation, konkurrenskraftiga företag, förstklassig forskning samt välfungerande myndigheter och institutioner. I den politiska debatten idag finns en förväntan att Sverige ska upprätthålla sin konkurrenskraft och bemöta samhällets utmaningar genom innovation och att vägen till innovation går via samverkan. Avhandlingen bygger på en studie av ett samverkansprojekt vars syfte var att skapa innovation för att minska antalet vårdrelaterade infektioner i Sverige. Projektet som studerats ses som en transdisciplinär ansats med aktörer som representerade akademi, industri samt hälso- och sjukvård.

    Syftet med avhandlingen är att vidareutveckla kunskapen om interorganisatorisk samverkan för innovation. Detta görs genom ett tredelat bidrag, till teoribildningen kring samverkan för innovation som börjat växa fram, till den samverkande praktiken inom både privat och offentlig sektor samt till politiker och beslutsfattare som styr fördelning av statliga anslag till forskning och innovation.

    Fallstudien som ligger till grund för avhandlingen är baserad på en etnografiskt inspirerad studie. Empiriskt material samlades in och skapades tillsammans med aktörerna i projektet under drygt två års tid genom intervjuer och deltagande observation.

    Studien visar att interorganisatorisk samverkan består av flera dimensioner och kan förstås på flera nivåer. Interorganisatorisk samverkan innebär inte bara att det är olika organisationer som ska göra en gemensam ansträngning. Organisationerna består av olika människor med olika discipliner och professioner vilka bygger på olika utgångspunkter och sätt att se på världen. Samverkan kan ses som ett sätt att fylla mellanrummen mellan organisationer istället för att bygga broar över gränser. I de organisatoriska mellanrummen kan aktörer från olika organisationer, med olika discipliner och professioner mötas utan institutionaliserade roller, i en receptiv kontext där innovation kan skapas.

  • 12.
    Baban, Hanna
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Grauning, Olivia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Using Fetal Myocardial Velocity Recordings to Evaluate an AI Platform to Predict High-risk Deliveries2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Diagnosing abnormal fetal cardiac function using ultrasound is a complicated procedure which makes it difficult to obtain high quality results from ultrasound examinations that are performed shortly before delivery. Color tissue Doppler imaging (cTDI) is the echocardiographic technique that has been used to obtain the data for this project. Subtle changes in the fetal cardiac function caused by a variety of complications can possibly be detected using cTDI. Fetuses suffering from these complications are often involved in high-risk deliveries. Combining the data obtained from cTDI with Artificial Intelligence (AI) may improve precision and accuracy when it comes to diagnosing pathological conditions involving fetal cardiac function before delivery. AI uses machines to perform and execute tasks that are characteristic of human intelligence. AI can be achieved by using deep learning. Deep learning uses algorithms called artificial neural networks that are inspired by the biological structure and function of the human brain. The neural networks classify information in a similar manner to the human brain. A platform that uses deep learning can make statements or predictions based on the data fed to it. The AI platform Peltarion uses deep learning to perform tasks. The aim of this project was to use Peltarion to evaluate the possibility of predicting high-risk deliveries with abnormal perinatal outcome by using data obtained by cTDI velocity recordings of the fetal heart. The data included myocardial velocity recordings from 107 pregnancies, out of the 107 pregnancies 82 of the babies were born healthy while 25 babies had an adverse perinatal outcome. The data was uploaded in the platform and three models were built and trained in order to evaluate the performance of the platform using the data. The parameters that have been used to determine the results are loss, accuracy and precision. The results showed that the accuracy parameter was measured to be 0.8 in all cases which means that the model correctly predicts if a fetal heart is healthy or likely to have an adverse outcome 80% of the time. The precision parameter was measured to be around 0.4 which means out of all the times the model predicted a fetal heart to have an adverse outcome, only 40% truly had an adverse outcome. It was concluded that a substantially larger amount of evenly distributed data is required to appropriately evaluate the possibility of using fetal myocardial velocity recordings as data for the AI platform Peltarion to predict high-risk deliveries.

  • 13. Belfrage, Sara
    Without informed consent2013Ingår i: Moral, Ethical, and Social Dilemmas in the Age of Technology: Theories and Practice, IGI Global, 2013, s. 291-305Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    The requirement of always obtaining participants' informed consent in research with human subjects cannot always be met, for a variety of reasons. This paper describes and categorises research situations where informed consent is unobtainable. Some of these kinds of situations, common in biomedicine and psychology, have been previously discussed, whereas others, for example, those more prevalent in infrastructure research, introduce new perspectives. The advancement of new technology may lead to an increase in research of these kinds. The paper also provides a review of methods intended to compensate for lack of consent, and their applicability and usefulness for the different categories of situations are discussed. The aim of this is to provide insights into one important aspect of the question of permitting research without informed consent, namely, how well that which informed consent is meant to safeguard can be achieved by other means.

  • 14.
    Blom, Hans
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Cellens fysik. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Brismar, Hjalmar
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Cellens fysik. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    STED microscopy: increased resolution for medical research?2014Ingår i: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 276, nr 6, s. 560-578Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Optical imaging is crucial for addressing fundamental problems in all areas of life science. With the use of confocal and two-photon fluorescence microscopy, complex dynamic structures and functions in a plethora of tissue and cell types have been visualized. However, the resolution of classical' optical imaging methods is poor due to the diffraction limit and does not allow resolution of the cellular microcosmos. On the other hand, the novel stimulated emission depletion (STED) microscopy technique, because of its targeted on/off-switching of fluorescence, is not hampered by a diffraction-limited resolution barrier. STED microscopy can therefore provide much sharper images, permitting nanoscale visualization by sequential imaging of individual-labelled biomolecules, which should allow previous findings to be reinvestigated and provide novel information. The aim of this review is to highlight promising developments in and applications of STED microscopy and their impact on unresolved issues in biomedical science.

  • 15.
    Boström, Caroline
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Messler, Olivia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Design and Evaluation of a 3D Printed Ionization Chamber2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Ionizing radiation is often used within medicine for diagnosis and treatments. Because ionizingradiation can be harmful to the body, it is important to know how it affects the tissue. Dosimetryis the study of how ionizing radiation deposits energy in a material. To measure how much ionizingradiation is deposited in the body, gas-filled detectors are often used. An ionization chamber isa type of gas-filled detector and exists in different shapes and sizes, depending on what kind ofmeasurements it is made for. Because ionization chambers are relatively expensive, it is often notpossible to buy one for each type of measurement that is to be done. This results in ionizationchambers being used for measurements they are not optimized for. This report evaluates thepossibility of 3D printing ionization chambers to make it easier to optimize them for specificmeasurements. The process included creating models of ionization chambers using CAD-software,slicing them and then 3D printing them. The 3D printed models were then brought to the SwedishRadiation Safety Authority for measurements. The ionization chambers were connected to highvoltage, and exposed to ionizing radiation in the form of high-intensity gamma-ray fields. Theoutput current of the ionization chamber was measured, which is proportional to the field intensity.The results were similar to those of a commercial ionization chamber. The conclusion is that it ispossible to 3D print ionization chambers. However, to get more accurate results, the design has tobe further optimized and more measurements need to be done.

  • 16.
    Broomé, Michael
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinsk bildteknik.
    Frenckner, Björn
    Broman, Mikaeö
    Bjällmark, Anna
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinsk bildteknik.
    Recirculation during veno-venous extra-corporeal membrane oxygenation: a simulation study2015Ingår i: International Journal of Artificial Organs, ISSN 0391-3988, E-ISSN 1724-6040, Vol. 38, nr 1, s. 23-30Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE:

    Veno-venous ECMO is indicated in reversible life-threatening respiratory failure without life-threatening circulatory failure. Recirculation of oxygenated blood in the ECMO circuit decreases efficiency of patient oxygen delivery but is difficult to measure. We seek to identify and quantify some of the factors responsible for recirculation in a simulation model and compare with clinical data.

    METHODS:

    A closed-loop real-time simulation model of the cardiovascular system has been developed. ECMO is simulated with a fixed flow pump 0 to 5 l/min with various cannulation sites - 1) right atrium to inferior vena cava, 2) inferior vena cava to right atrium, and 3) superior+inferior vena cava to right atrium. Simulations are compared to data from a retrospective cohort of 11 consecutive adult veno-venous ECMO patients in our department.

    RESULTS:

    Recirculation increases with increasing ECMO-flow, decreases with increasing cardiac output, and is highly dependent on choice of cannulation sites. A more peripheral drainage site decreases recirculation substantially.

    CONCLUSIONS:

    Simulations suggest that recirculation is a significant clinical problem in veno-venous ECMO in agreement with clinical data. Due to the difficulties in measuring recirculation and interpretation of the venous oxygen saturation in the ECMO drainage blood, flow settings and cannula positioning should rather be optimized with help of arterial oxygenation parameters. Simulation may be useful in quantification and understanding of recirculation in VV-ECMO.

  • 17. Brown, Shannon
    et al.
    Ortiz-Catalan, Max
    Petersson, Joel
    Rodby, Kristian
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Data- och elektroteknik. University of Borås, Sweden.
    Intarsia-Sensorized Band and Textrodes for Real-Time Myoelectric Pattern Recognition2016Ingår i: Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS / [ed] Patton, J Barbieri, R Ji, J Jabbari, E Dokos, S Mukkamala, R Guiraud, D Jovanov, E Dhaher, Y Panescu, D Vangils, M Wheeler, B Dhawan, AP, Institute of Electrical and Electronics Engineers (IEEE), 2016, s. 6074-6077, artikel-id 7592114Konferensbidrag (Refereegranskat)
    Abstract [en]

    Surface Electromyography (sEMG) has applications in prosthetics, diagnostics and neuromuscular rehabilitation. Self-adhesive Ag/AgCl are the electrodes preferentially used to capture sEMG in short-term studies, however their long-term application is limited. In this study we designed and evaluated a fully integrated smart textile band with electrical connecting tracks knitted with intarsia techniques and knitted textile electrodes. Real-time myoelectric pattern recognition for motor volition and signal-to-noise ratio (SNR) were used to compare its sensing performance versus the conventional Ag-AgCl electrodes. After a comprehending measurement and performance comparison of the sEMG recordings, no significant differences were found between the textile and the Ag-AgCl electrodes in SNR and prediction accuracy obtained from pattern recognition classifiers.

  • 18.
    Buendia, Ruben
    et al.
    University of Borås, Sweden.
    bogonez-franco, Paco
    Technical University of Catalonia.
    Nescolarde, Lexa
    Technical University of Catalonia.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Influence of electrode mismatch on Cole parameter estimation from Total Right Side Electrical Bioimpedance Spectroscopy measurements2012Ingår i: Medical Engineering and Physics, ISSN 1350-4533, E-ISSN 1873-4030, Vol. 34, nr 7, s. 1024-1028Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Applications based on measurements of Electrical Bioimpedance (EBI) spectroscopy analysis, like assessment of body composition, have proliferated in the past years. Currently Body Composition Assessment (BCA) based in Bioimpedance Spectroscopy (BIS) analysis relays on an accurate estimation of the Cole parameters R-0 and R-infinity. A recent study by Bogonez-Franco et al. has proposed electrode mismatch as source of remarkable artefacts in BIS measurements. Using Total Right Side BIS measurements from the aforementioned study, this work has focused on the influence of electrode mismatch on the estimation of R-0 and R-infinity using the Non-Linear Least Square curve fitting technique on the modulus of the impedance. The results show that electrode mismatch on the voltage sensing electrodes produces an overestimation of the impedance spectrum leading to a wrong estimation of the parameters R-0 and R-infinity, and consequently obtaining values around 4% larger that the values obtained from BIS without electrode mismatch. The specific key factors behind electrode mismatch or its influence on the analysis of single and spectroscopy measurements have not been investigated yet, no compensation or correction technique is available to overcome the deviation produced on the EBI measurement. Since textile-enabled EBI applications using dry textrodes, i.e. textile electrodes with dry skin-electrode interfaces and potentially large values of electrode polarization impedance are more prone to produce electrode mismatch, the lack of a correction or compensation technique might hinder the proliferation of textile-enabled EBI applications for personalized healthcare monitoring.

  • 19.
    Callerström, Emma
    KTH, Skolan för teknik och hälsa (STH).
    Clinicians' demands on monitoring support in an Intensive Care Unit: A pilot study, at Capio S:t Görans Hospital2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Patienter som vårdas på intensivvårdsavdelningar har svikt i ett eller flera organ. Övervakning sker av patienterna för att kunna bidra till den vård som behövs för att upprätthålla ett meningsfullt liv. Idag hanterar sjukvårdpersonal en stor mängd data som genereras från övervakningsutrustning och system förknippade med övervakningsutrustning. Övervakningsparameterar kan antecknas förhand på ett övervakningspapper eller direkt sparas i digitalt format. Parameterarna sparas med syfte att vara ett lättillgängligt underlag under hela intensivvårdsprocessen. Patient data management systems (PDMSs) förenklar hämtning och integrering av data på exempelvis intensivvårdsavdelningar. Innan en ny konfiguration av ett patientdatasystem erhålls, är det eftersträvnadsvärt att intensivvårdsavdelningen analyserar vilken datasom skall hanteras. Detta examensarbete bidrog till kunskap om hur övervakning utförs på en intensivvårdsavdelning, på ett akutsjukhus i Stockholm. Målet med detta examensarbete var att insamla data om vad klinikerna behöver och vilken utrustning och system som de använder idag för att utföra övervakning. Behovsframkallning är en teknik som kan användas för att insamla krav. I detta projekt insamlades data genom aktivaobservationer och kvalitativa intervjuer. Mönster har hittats bland undersköterskornas, sjuksköterskornas och läkarnas behov av teknisksupport från system och utrustning som stödjer sjukvårdspersonalen under övervakningen av en patient. Undersköterskor uttrycker ett behov av att bli avlastade från uppgifter så som att manuellt skrivaner vitala parametervärden. De ifrågasätter behovet av automatiserad datahämtning eftersom de ständigt är närvarande bredvid patienten. Sjuksköterskor beskriver en hög vårdtyngd och önskaratt inte bli tillägnade fler aktiviteter som ökar den vårdtyngden. Läkare beskriver ett behov av ökat stöd för hur en interversion leder till resultat för individuella patienter. Resultaten visar attdet finns information om möjliga kliniska beslutsstöd utan givet sätt att applicera dessa, bättre än de sätt som används idag. Sjukvårdspersonalen hävdar att det det finns ett behov av att utvärdera det kliniska arbetet med hjälp av övervakningsparametrar. Resultaten utgör kunskap om vilka områden som sjukvårdpersonalens behov inte har stöd av nuvarnade verktyg. Resultaten visar att beroende på vilken profession och erfarenhet som sjukvårdspersonalen har, är behoven olika. På intensivvårdsavdelningen sker övervakning då enskilda patienter visuellt observeras såväl som övervakningsparametrar från medicintekniska produkter, resultat från medicinska tester och fysiska examinationer. Det finns behov att integrera och presenterainformation från dessa källor givet kunskap om att sjukvårdpersonalen fattar beslut på dessa som resulterar i behandling, diagnostik och/eller vård.

  • 20. Capece, Sabrina
    et al.
    Chiessi, Ester
    Cavalli, Roberta
    Giustetto, Pierangela
    Grishenkov, Dmitry
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinsk avbildning.
    Paradossi, Gaio
    A general strategy for obtaining biodegradable polymer shelled microbubbles as theranostic devices2013Ingår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 49, nr 51, s. 5763-5765Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fabrication of multifunctional ultrasound contrast agents (UCAs) has been recently addressed by several research groups. A versatile strategy for the synthesis of UCA precursors in the form of biodegradable vesicles with a biocompatible crosslinked polymer shell is described. Upon ultrasound irradiation, acoustic droplet vaporization transforms such particles into microbubbles behaving as UCAs. This proof of concept entails the features of a potential theranostic microdevice.

  • 21.
    Chen, Hongjian
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Larsson, David
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Janerot-Sjöberg, Birgitta
    Colarieti-Tosti, Massimiliano
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Grishenkov, Dmitry
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Polymer Microbubbles as Dual Modal Contrast Agent for Ultrasound and Computed Tomography2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    The hybrid imaging combines the anatomical information with the functional or metabolic information using different conventional single imaging modalities improving the overall diagnosis outcome of the clinical examination. Since the introduction of the first hybrid imaging device PET-CT in 1998 different combinations of hybrid imaging were developed such as PET-MRI, SPECT-CT.

    However, lack of multimodal contrast agent specifically aimed for hybrid imaging limits the diagnostic outcome of these novel techniques. Initial attempts in fabrication of hybrid contrast agents were made by combining previously existing single modal contrast agents into one. In this study, polyvinyl alcohol (PVA) microbubbles (MB) and gold nanoparticles - which by themselves are already established contrast agents used in preclinical studies for ultrasound and CT, respectively - were chosen as parent contrast agents to fabricate the dual modal Contrast Agent for UltraSound and CT (CACTUS).

    Method

    The fabrication of MBs was adapted from Cavalieri et al.[1]. PVA powder (Sigma Aldrich, MO USA) was dissolved in the water at 80°C. The aqueous PVA-chains were cleaved by sodium metaperiodate (NaIO4, purity>99.0%, Sigma Aldrich, MO USA). Vigorous stirring force was applied to the resulting telechelic aldehydic PVA-chains for 2 hours to crosslink the telechelic aldehydic PVA-chains and form the PVA-coated MBs at the water-air interface.

    CACTUS MBs were synthesized in a similar fashion to the above, but adding gold nanoparticles (diameter 1.9nm, Nanoprobes, NY, USA) during formation of the MBs.

    The size distributions of MBs and CACATUS MBs were determined using an optical microscope (ECLIPSE Ci-S, Nikon, Tokyo, Japan) and a Neubauer counting chamber (Brand GmbH, Wertheim, Germany).

    The acoustic attenuation coefficients of the MBs suspension were acquired at peak negative pressure (PNP) from 10 - 300 kPa. Three MBs suspension samples with concentrations of (sample A),  (sample B) and  ml-1 (sample C) were prepared and loaded in a 1 cm thick two-cavity chamber. A flat single crystal ultrasound transducer with central frequency 3.5MHz was used to generate the ultrasound beam. The amplitude of received echoes through samples and water were compared at the fundamental frequency, as well as the 2nd and 3rd harmonic for each value of the concentration used.

    The mass attenuation of water, suspension of gold nanoparticles with concentration 160mg/L, plain MBs, and CACTUS MBs, was measured by quantum FX-CT micro-CT (PerkinElmer Inc, MA, USA). The micro-CT was operated at a current of 200mA with exposure time of 120s and varied voltage 50kV, 70kV and 90kV. Each 3D image has a size of 512*512*512 pixels or 75.8*75.8*75.8 mm. Contrast to noise ratios (CNR) between water and all samples were calculated following Eq. 1.Where S(x,y,z) and W(x,y,z) are the mass attenuation of the sample and water per voxel, respectively. ns(x,y,z) and nw(x,y,z) are the noise function with zero mean of sample and water respectively. Ms and Mw are the mean mass attenuation acquired for the sample and water in the volume of interest. The σs2 and σw2 are the variance of the mass attenuation read out of the sample and water in the volume of interested.

    In addition to the gas-core MBs for the CT tests, liquid-core gold loaded capsules were synthesized in two steps. In the first step, PVA shelled liquid-core capsules were obtained by exposing MBs to 66% v/v ethanol solution. In the second step, the resulting liquid-core capsules were mixed with high concentration gold nanoparticles suspension and homogenized by a shaker (MS 3 basic, IKA, Königswinter Germany) at 500rpm for 1 hour for goal loading. The resulting gold loaded capsules were washed with Milli-Q water using centrifuge (Galaxy 5D digital microcentrifuge, VWR, USA) at a speed of 1000 g for 5 min.

    Results and discussion

    The mean diameter of MBs is 3.6±1.1 μm. The mean diameter of CACTUS MBs is 3.2±0.7 μm. The size distribution of the gold loaded capsules was not investigated separately, but rather assumed identical to the plain MBs. The number and the volume distribution of MBs and CACTUS MBs are shown in figure 1. The results demonstrate that most of the CACTUS MBs and MBs have a diameter from 1 to 6 μm. Therefore, they are able pass through the capillaries and will resonate within typical clinical diagnostic ultrasound frequency below 15 MHz.

    Pressure dependent acoustic attenuation coefficients of the sample A, B, and C are shown in figure 2. The results show that attenuation coefficients of sample A and B at the fundamental frequency stay constant and slightly increase at the second harmonic at the PNP below 100kPa, indicating a linear oscillation of MBs. As the PNP reaches 200kPa, the attenuation coefficient of sample A at fundamental frequency decreases while at 2nd and 3rd harmonics increases, indicating that the energy of the echo shifts from the fundamental frequency to the 2nd and 3rd harmonics. As the PNP goes higher to 300kPa, the attenuation coefficient of sample A at the fundamental frequency, 2nd, and 3rd harmonics decreases, suggesting that the energy shifts to an even higher harmonic. At the same time, the attenuation coefficient of sample B stays constant at fundamental frequency, decreases at 2nd harmonics, and increases at the 3rd harmonic, suggesting the energy starts to shift to the 3rd harmonic. The attenuation coefficient of sample C at fundamental frequency, 2nd and 3rd harmonics keep constant and low due to low sample concentration. The test reveals the energy shifting of the echo to the higher harmonics at PNP higher than 100 kPa, indicating the nonlinear oscillation of MBs at PNP higher than 100 kPa. Moreover, the concentration of the MBs seems to influence the energy shifting: the higher the concentration the earlier the shift to the higher harmonics occurs, in the range of the concentration consider in this study.

    The pilot results of the micro-CT tests are presented in Table 1. The reference, gold nanoparticles solution, has the highest CNR per voxel at all CT operating voltages. The CNR per voxel of CACTUS MBs suspensions is below 0.1, virtually equaling the MBs at all operating voltages, suggesting that no gold or very little gold were loaded into the shell of the CACTUS MBs. The gold loaded capsules suspension has higher CNR per voxel than the capsule supernatant (the surrounding environment of capsules) and the MBs suspension, implying that the gold nanoparticles were loaded into the capsules. However, it is not clear whether the gold nanoparticles were loaded in the core of the MBs or in the MBs shell. The expected sharp increase of CNR per voxel at the k-edge of gold did not appear. We believe that is because even at our highest operating voltage of 90kV, the percentage of the photons with energy higher than 80.7 keV is still low. Introduction of a high-pass metal filter could increase the percentage of high energy photon. On the other hand, the metal filter will reduce the total number of the photons which would increase the noise of the images. Since same current was applied on every CT test, less X-ray photons reached the sensors when the CT was operated at low voltage. Therefore, it might be worth performing additional calibration tests to adjust the operating currents to make sure that the numbers of the photons that reach the sensor at every operating voltage are the same.

    Conclusion

    In this study, the CACTUS MBs and gold loaded capsules were fabricated as potential candidates for dual modal contrast agent. The characterization revealed that gold loaded capsule is a promising initial step. Nevertheless, the method to convert back liquid-core capsules to gas-core MBs needs to be established.

    [1] Cavalieri, F., El Hamassi, A., Chiessi, E., Paradossi, G., Villa, R., & Zaffaroni, N. (2006). Tethering functional ligands onto shell of ultrasound active polymeric microbubbles. Biomacromolecules, 7(2), 604-611.

  • 22.
    Cloots, Rudy J.H.
    et al.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    van Dommelen, J.A.W.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Geers, Marc
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Multi-scale mechanics of traumatic brain injury: predicting axonal strains from head loads2013Ingår i: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 12, nr 1, s. 137-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The length scales involved in the development of diffuse axonal injury typically range from the head level (i.e., mechanical loading) to the cellular level. The parts of the brain that are vulnerable to this type of injury are mainly the brainstem and the corpus callosum, which are regions with highly anisotropically oriented axons. Within these parts, discrete axonal injuries occur mainly where the axons have to deviate from their main course due to the presence of an inclusion. The aim of this study is to predict axonal strains as a result of a mechanical load at the macroscopic head level. For this, a multi-scale finite element approach is adopted, in which a macro-level head model and a micro-level critical volume element are coupled. The results show that the axonal strains cannot be trivially correlated to the tissue strain without taking into account the axonal orientations, which indicates that the heterogeneities at the cellular level play an important role in brain injury and reliable predictions thereof. In addition to the multi-scale approach, it is shown that a novel anisotropic equivalent strain measure can be used to assess these micro-scale effects from head-level simulations only.

  • 23.
    Cloots, Rudy J.H.
    et al.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    van Dommelen, JAW
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Geers, Marc
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Traumatic Brain Injury at Multiple Length Scales: Relating Diffuse Axonal Injury to Discrete Axonal Impairment2010Ingår i: 2010 INTERNATIONAL IRCOBI CONFERENCE ON THE BIOMECHANICS OF INJURY PROCEEDINGS, 2010, s. 119-130Konferensbidrag (Refereegranskat)
  • 24.
    Courteille, Olivier
    et al.
    Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Fahlstedt, Madelen
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Neuronik.
    Ho, Johnson
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Neuronik.
    Hedman, Leif
    Department of Psychology, Umeå University, Umeå, Sweden.
    Fors, Uno
    Department of Computer and Systems Sciences, Stockholm University, Stockholm, Sweden.
    von Holst, Hans
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Neuronik.
    Felländer-Tsai, Li
    Department of Clinical Science, Intervention and Technology, Division of Orthopaedics and Biotechnology, Karolin-ska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Möller, Hans
    Department of Clinical Science, Intervention and Technology, Division of Orthopaedics and Biotechnology, Karolin-ska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Learning through a virtual patient vs. recorded lecture: a comparison of knowledge retention in a trauma case2018Ingår i: International Journal of Medical Education, ISSN 2042-6372, E-ISSN 2042-6372, Vol. 9, s. 86-92Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: To compare medical students' and residents' knowledge retention of assessment, diagnosis and treatment procedures, as well as a learning experience, of patients with spinal trauma after training with either a Virtual Patient case or a video-recorded traditional lecture. Methods: A total of 170 volunteers (85 medical students and 85 residents in orthopedic surgery) were randomly allocated (stratified for student/resident and gender) to either a video-recorded standard lecture or a Virtual Patient-based training session where they interactively assessed a clinical case portraying a motorcycle accident. The knowledge retention was assessed by a test immediately following the educational intervention and repeated after a minimum of 2 months. Participants' learning experiences were evaluated with exit questionnaires. A repeated-measures analysis of variance was applied on knowledge scores. A total of 81% (n = 138) of the participants completed both tests. Results: There was a small but significant decline in first and second test results for both groups (F-(1,F-135) = 18.154, p = 0.00). However, no significant differences in short-term and long-term knowledge retention were observed between the two teaching methods. The Virtual Patient group reported higher learning experience levels in engagement, stimulation, general perception, and expectations. Conclusions: Participants' levels engagement were reported in favor of the VP format. Similar knowledge retention was achieved through either a Virtual Patient or a recorded lecture.

  • 25.
    Cuba-Gyllensten, Illapha
    et al.
    KTH, Skolan för teknik och hälsa (STH). Philips Research Europe, High Tech. Campus 34, 5656AE, Eindhoven, Netherlands; ACTLab., Signal Processing Systems, TU Eindhoven, 5600MB Eindhoven, Netherlands.
    Abtahi, Farhad
    Philips Research Europe, High Tech. Campus 34, 5656AE, Eindhoven, Netherlands.
    Bonomi, Alberto G.
    KTH, Skolan för teknik och hälsa (STH).
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. University of Borås, Sweden.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. Karolinska Institute, Sweden.
    Amft, O.
    ACTLab., Signal Processing Systems, TU Eindhoven, 5600MB Eindhoven, Netherlands.
    Removing respiratory artefacts from transthoracic bioimpedance spectroscopy measurements2013Ingår i: XV International Conference on Electrical Bio-Impedance (ICEBI) & XIV Conference on Electrical Impedance Tomography (EIT), Institute of Physics Publishing (IOPP), 2013, Vol. 434, nr 1Konferensbidrag (Refereegranskat)
    Abstract [en]

    Transthoracic impedance spectroscopy (TIS) measurements from wearable textile electrodes provide a tool to remotely and non-invasively monitor patient health. However, breathing and cardiac processes inevitably affect TIS measurements, since they are sensitive to changes in geometry and air or fluid volumes in the thorax. This study aimed at investigating the effect of respiration on Cole parameters extracted from TIS measurements and developing a method to suppress artifacts. TIS data were collected from 10 participants at 16 frequencies (range: 10 kHz - 1 MHz) using a textile electrode system (Philips Technologie Gmbh). Simultaneously, breathing volumes and frequency were logged using an electronic spirometer augmented with data from a breathing belt. The effect of respiration on TIS measurements was studied at paced (10 and 16 bpm) deep and shallow breathing. These measurements were repeated for each subject in three different postures (lying down, reclining and sitting). Cole parameter estimation was improved by assessing the tidal expiration point thus removing breathing artifacts. This leads to lower intra-subject variability between sessions and a need for less measurements points to accurately assess the spectra. Future work should explore algorithmic artifacts compensation models using breathing and posture or patient contextual information to improve ambulatory transthoracic impedance measurements.

  • 26.
    Danko, Charlott
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Hägglund, Stina
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Utveckling av en applikation för rullstolsflödet på Karolinska Universitetssjukhuset i Solna2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens samhälle har spårbarhet av medicintekniska hjälpmedel fått en allt viktigare innebörd inom sjukvården. En anledning till det är att de flesta hjälpmedel klassas som medicintekniska produkter vilka enligt Socialstyrelsens föreskrifter måste kunna spåras. Därför märks många hjälpmedel med streckkoder eller liknande markörer. På Karolinska Universitetssjukhuset i Solna önskar man förbättra spårbarheten av rullstolar och få en bättre översikt över vilka som är utlånade och förskrivna.

    En metod för att lösa detta problem är genom att digitalisera flödesprocessen för rullstolar. I det här arbetet har ett digitalt program utvecklats för att ersätta ett antal steg i flödesprocessen som i nuläget hanteras manuellt med penna och papper. Genom att digitalisera delar av processen och se över möjligheter att implementera scanners kan informationen kvalitetssäkras och arbetet effektiviseras. Resultatet visar att ett sådant program som det som utvecklades skulle vara gynnsamt för sjukhuset och skulle bidra till en bättre kontroll över rullstolsflödet. I och med arbetet har en god grund lagts för att digitalisera hanteringen av hjälpmedel och utveckla processerna.

  • 27. Deck, C.
    et al.
    Bourdet, N.
    Halldin, Peter
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Neuronik.
    DeBruyne, G.
    Willinger, R.
    Protection capability of bicycle helmets under oblique impact assessed with two separate brain FE models2017Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI, International Research Council on the Biomechanics of Injury , 2017, s. 190-200Konferensbidrag (Refereegranskat)
    Abstract [en]

    The present study proposes a bicycle helmet evaluation under oblique impact based on a coupled experimental versus numerical test method using two separate brain FE models. For each of the 17 helmet types three oblique impacts have been conducted and the 6D headform acceleration curves have been considered as the initial conditions of the brain injury risk assessment based on the FE simulation. The study gives a new insight into helmet protection capability under oblique loading and shows that adequate protection is offered by most of the helmets when impacts leading to rotation around X and Y are concerned. However when impact leads to rotation around Z axis the protection is critical for nearly all helmets. The study considers two separate brain FE models for the assessment of brain injury risk and thus permits a comparative analysis of brain FE modeling. When impact induces rotation around X and Y axis the computed results are comparable. However when rotation around Z axis are concerned significant differences are observed which demonstrate that further efforts are needed in the domain of model based brain injury criteria harmonization. 

  • 28.
    Dizdarevic, Sven
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Hämäläinen, Anton
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Developing a simulation model for decision making in a further digitized Swedish healthcare system2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Tack vare datorsimuleringar kan beslutsfattare inom sjukv˚arden b¨attre ¨an n˚agonsin f¨orst˚a och utv¨ardera konsekvenserna av sina beslut. ˚Ar 2016 publicerade den svenska regeringen ”Vision eH¨alsa 2025”. Dokumentet betonade vikten av digitalisering inom sjukv˚arden. Det h¨ar examensarbetet syftar p˚a att studera de aktuella krav som finns inom eH¨alsa i Sverige, och ¨aven simuleringsarkitekturen n¨odv¨andig f¨or att sanningsenligt simulera ett digitaliserat svenskt sjukv˚ardssystem. En omfattande litteraturstudie genomf¨ordes, f¨oljt av en implementationsfas, och till sist en valideringsprocess. F¨orst drogs slutsatsen att f¨oljande tre omr˚aden av eH¨alsa skulle bidra med stor nytta till svensk sjukv˚ard: ett fullst¨andigt integrerat journalsystem, system f¨or v˚ardkonsultationer ¨over internet, och system f¨or tele¨overvakning av kroniker och ¨aldre patienter. Sedan unders¨oktes trov¨ardigheten av en f¨orsedd f¨orsta version av en simuleringsarkitektur, och dess potentiella omr˚aden f¨or f¨orb¨attringar identifierades. Den p˚af¨oljande implementationsfasen inkluderade modifieringar till f¨oljande aspekter av den f¨orsedda simuleringsplattformen: generalitetsniv˚a, patientagentklassen (pHome), sjukv˚ardsresurser, sjukdomsdynamik & olika niv˚aer av v˚ardleverans, logiken bakom arbetsfl¨odesdiagrammen, optimiseringskriterier, anv¨andargr¨anssnittet, och outputvariabler. Valideringsprocessen bestod av fyra intervjuer med professionela yrkesm¨an kunniga om det svenska sjukv˚ardssystemet. Simuleringsplattformen demonstrerades under alla fyra intervjuer. Slutsatsen drogs att detaljniv˚an hos den utvecklade simuleringsplattformen inte ¨ar tillr¨acklig i nul¨aget f¨or att utf¨ora korrekta simuleringar. Framf¨or allt saknar outputvariablerna specificitet. Det ¨ar fortfarande inte k¨ant vilken detaljniv˚a som skulle vara tillr¨acklig i det h¨ar avseendet.

  • 29.
    Dånmark, Staffan
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Gladnikoff, Micha
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Frisk, Thomas
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Cellens fysik.
    Zelenina, Marina
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Cellens fysik.
    Mustafa, Kamal
    Russom, Aman
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Finne-Wistrand, Anna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Development of a novel microfluidic device for long-term in situ monitoring of live cells in 3-dimensional matrices2012Ingår i: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 14, nr 5, s. 885-893Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using the latest innovations in microfabrication technology, 3-dimensional microfluidic cell culture systems have been developed as an attractive alternative to traditional 2-dimensional culturing systems as a model for long-term microscale cell-based research. Most microfluidic systems are based on the embedding of cells in hydrogels. However, physiologically realistic conditions based on hydrogels are difficult to obtain and the systems are often too complicated. We have developed a microfluidic cell culture device that incorporates a biodegradable rigid 3D polymer scaffold using standard soft lithography methods. The device permits repeated high-resolution fluorescent imaging of live cell populations within the matrix over a 4 week period. It was also possible to track cell development at the same spatial location throughout this time. In addition, human primary periodontal ligament cells were induced to produce quantifiable calcium deposits within the system. This simple and versatile device should be readily applicable for cell-based studies that require long-term culture and high-resolution bioimaging.

  • 30.
    Ekelund, Emil
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Fogelberg Skoglösa, David
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem.
    Geant4 Simulations of Hadron Therapy and Refinement of User Interface2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Radiotherapy is one of the most used methods for treating cancer and the most common way to execute such treatments is to irradiate tumors with high energy photons. This can damage healthy tissue along the irradiation line. By using hadron therapy and instead irradiate the tumor with charged particles (protons or Carbon 12 ions), the energy can be concentrated to a more specific place in the body. However, the method is not well studied and the tools available for simulating hadron therapy can be hard to use.

    When simulating hadron therapy and other nuclear interactions a large amount of calculations need to be executed. Monte Carlo methods is a numerical method to solve equations based on repeated number sampling and is used in the simulation program Geant4. Hadron therapy was simulated with Geant4 and the data was analyzed with the data analysis framework ROOT. New macros and analysis scripts were created with the intention to help new Geant4 users. The aim to make Geant4 easier to use was partially met. The implementation of code for the low energy region of Carbon 12 projectiles was unsuccessful.

  • 31.
    Fahlstedt, Madelen
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Baeck, Katrien
    Mechanical Engineering Department, Biomechanics Section, Katholieke Universiteit Leuven, Belgium.
    Halldin, Peter
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Vander Sloten, Jos
    Mechanical Engineering Department, Biomechanics Section, Katholieke Universiteit Leuven, Belgium.
    Goffin, Jan
    Mechanical Engineering Department, Biomechanics Section, Katholieke Universiteit Leuven, Belgium.
    Depreitere, Bart
    Mechanical Engineering Department, Biomechanics Section, Katholieke Universiteit Leuven, Belgium.
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Influence of impact velocity and angle in a detailed reconstruction of a bicycle accident2012Ingår i: 2012 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury, 2012, s. 787-799Konferensbidrag (Refereegranskat)
    Abstract [en]

    Bicycle accidents have become the most common cause of serious injury in the traffic during the last couple of years in Sweden. The objective of this study was to investigate the effect of the input variables, initial velocity and head orientation, of a bicycle accident reconstruction on the strain levels in the brain using a detailed FE head model. The accident involved a non-helmeted 68 year old male who sustained a linear skull fracture, contusions, acute subdural hematoma, and small bleeding at the swelling (subarachnoid blood). The orientation of the head just before impact was determined from the swelling appearing in the computer tomography (CT) scans. The head model used in this study was developed at the Royal Institute of Technology in Stockholm. The stress in the cranial bone, first principal strain in the brain tissue and acceleration were determined. The model was able to predict a strain pattern that correlated well with the medical images from the victim. The variation study showed that the tangential velocity had a large effect on the strain levels in the studied case. The strain pattern indicated larger areas of high strain with increased tangential velocity especially at the more superior sections.

  • 32.
    Falck, Josefina
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik.
    Effect of side windows, stiffening plate and roof sheet on the stiffness of the bus body2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    As a bus developer, Scania focus to construct a safe vehicle for the passengers, i.e. high strength of the bus structure and good comfort, which is also profitable for the operator, i.e. high passenger capacity and low fuel consumption. The trade-off when developing a bus body structure is to get both high stiffness and low weight. The bus body including exterior panels plays together with the chassis an important role for the stiffness of the bus. By gathering knowledge about how various exterior panels affects the stiffness of the bus body, the design of the panels can be optimized with respect to high stiffness and low weight. Also from a calculation point of view is it of interest to know how important different panels are for the stiffness of the bus body, in order to make conscious simplifications in the calculation model.

    The aim with this master thesis was to investigate how the stiffening plate, side windows and roof sheet influence the strength of the bus body. How the thickness of the side windows affects the stiffness of the bus body is also investigated. The investigations were made as a relative comparison between a complete bus and comparison models.

     

    The results showed that exterior panels participate in distributing load. By distributing the load, the load uptake gets more efficient since a bigger part of the bus structure is used to take up the load. The side windows affect the stiffness for all tested load cases, with increased importance for the load case where a gravity field is applied in the longitudinal direction, for the torsion load case and when a load is applied to the power train in vertical direction. The roof sheet has a high impact on the stiffness in the torsion load case, but has negligible influence on the stiffness of the bus body for the other tested load cases. The stiffening plate has little influence on the stiffness of the bus body in general and is negligible for all tested load cases except for when a lateral load is applied as either a gravity field or locally to the power train.

     

    Thinner side windows are shown to have a positive influence on the stiffness of the bus body.

  • 33.
    Farhan, Amani
    et al.
    KTH, Skolan för teknik och hälsa (STH).
    Kardelind, Jonathan
    KTH, Skolan för teknik och hälsa (STH).
    IT- och informationssäkerhet inom prehospital vård: Kommunikation mellan ambulans och sjukhus inom Stockholms Läns Landsting och Region Kronoberg2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Den prehospitala vården är en viktig del av den svenska sjukvården, vårdprocessen innefattar all vård patient får utanför sjukhus. Den prehospitala vårdens kvalitet varierar hos olika landsting beroende på deras tekniska utrustningar och arbetsmetoder. Detta arbete utreder hur Region Kronoberg (RK) och Stockholms Läns Landsting (SLL) hanterar IT- och informationssäkerhet inom den prehospitala vården, då framförallt inom ambulanssjukvården.

     

    Arbetet har utförts via litteraturstudie kring lagar och riktlinjer som påverkar den prehospitala vården och sedan utfördes intervjuer för att finna hur RK och SLL hanterar patientjournaler.

     

    Arbetet visar att RK och SLL har jobbat olika länge med att digitalisera den prehospitala vårdprocessen, men att de idag använder lika säkra arbetsmetoder. Anledningen till detta är att bådas lösningar grundas i användandet av det säkra nätverket Sjunet. Vidare visade det sig att RK och SLL har olika grundförutsättningar för journalåtkomst. Avslutningsvis finner detta arbete inga säkerhetsrisker i anslutningen till de digitala journalsystemen, men att användandet av mobila enheter som lagrar journal utgör en säkerhetsrisk.

  • 34.
    Ferreira, Javier
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    AD5933-based electrical bioimpedance spectrometer: Towards textile-enabled applications2011Ingår i: Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS, 2011, Vol. 2011, s. 3282-3285Konferensbidrag (Refereegranskat)
    Abstract [en]

    Advances on System-On-Chip and Textile technology allows the development of Textile-enabled measurement instrumentation. Textile Electrodes (Textrodes) have been proven reliable for performing Electrical Bioimpedance Spectroscopy (EBIS) measurements, and the availability of a integrated circuit impedance spectrometer, the AD5933, has allowed the implementation of small size EBIS spectrometers. In this work an AD5933-based spectrometer has been implemented, and its performance on 2R1C circuits and for tetrapolar total right side EBIS measurements has been compared against the commercially available spectrometer SFB7. The study has been focused on the working upper frequency range and the estimation of the Cole parameters required for assessment of body fluid distribution: R(0) and R(∞). The results indicate that AD5933-based spectrometer implemented in this work can perform accurate impedance measurements well above the upper limits recommended in the datasheet. The AD5933-EBIS presents a good performance compared with the SFB7 on the 2R1C circuit and the total right side measurements, showing a smaller error in the resistance spectrum and small deviation error in the reactance when measuring over 270 kHz. The comparison on the Cole parameters estimation obtained with the SFB7 and the AD5933-based spectrometer exhibit a difference below 1% for the estimation of R(0) and R(∞). Consequently the overall measurement performance shown by the implemented AD5933-based spectrometer suggests its feasible use for EBIS measurements using dry Textrodes. This is of special relevance for the proliferation of EBI-based personalized health monitoring systems for patients that require to monitor the distribution of body fluids, like in dialysis.

  • 35.
    Fornstedt, Cecilia
    KTH, Skolan för teknik och hälsa (STH), Hälso- och systemvetenskap, Människa och Kommunikation. Välj.
    Medical Technology and eHealth for Prevention against LifestyleRelated Diseases: A survey of attitudes among health center personnel and patients prescribed with physical activity on prescription (PAP)2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Med en åldrande population som lider av samsjuklighet, står hälso- och sjukvården inför stora utmaningar. För att möta behovet är digitalisering en möjlighet. Digitalisering av åtgärdande vård, så som diagnostik och behandling, har redan påbörjats och är idag uppskattat. Preventiv vård har, å andra sidan, inte varit inkluderad i den digitala utvecklingen och därav saknas det vetenskapliga studier inom området. Dock är en mer proaktiv vård av stort intresse för flera aktörer. Sveriges regering har en vision att Sverige, år 2025, ska vara världsledande inom eHälsa. För att detta ska vara möjligt måste digital preventiv vård möta och komplettera det preventiva arbete som bedrivs idag.

    Denna studie har undersökt attityderna till Uppkopplade Medicinsktekniska Hjälpmedel för Prevention (UMHfP) bland primärvården. Genom en metod som inkluderat enkätundersökningar, inhämtades och analyserades attityden av 24 personer från personalen på vårdcentraler och 17 patienter med Fysisk Aktivitet på Recept (FaR). Resultaten visade att primärvårdspersonal är villiga att förskriva UMHfP och att patienter vill använda de hjälpmedlen som förskrivs. Dessutom har respondenterna tro att UMHfP kan underlätta att förbättra följsamheten till FaR utan att påverka personalens arbetsbörda nämnvärt.

    Genom att digitalisera den preventiva vården är det troligt att befolkningen kommer få ett hälsosammare leverne och därför inte behöva vård i samma utsträckning som idag. En anledning till detta är att digitala hjälpmedel för åtgärdande vård har visat sig vara positivt för kroniskt sjuka patienter som hemsjukvårdas. Dessutom har studier inom preventiv vård indikerat flera positiva konsekvenser för invånares hälsa världen över. Det är därför troligt att digitala hjälpmedel i kombination med preventivt arbete snabbt kommer bli uppskattat. Dessa spekulationer sammanfaller väl med det positiva resultatet från denna studie.

    Innan UMHfP kan förskrivas till patienter måste pilotstudier genomföras och nya arbetssätt inklusive betalningsmodeller måste införas i hälso- och sjukvården. Detta är kommande arbeten inom medicinsk teknik.

  • 36.
    Frykholm, Oscar
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Nilsson, Marcus
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Groth, Kristina
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Yngling, Alexander
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Interaction design in a complex context: medical multi-disciplinary team meetings2012Ingår i: The 7th Nordic Conference on Human-Computer Interaction: Making Sense Through Design, New York, NY, USA, 2012, s. 341-350Konferensbidrag (Refereegranskat)
    Abstract [en]

    In order to improve collaboration on, and visualisation of, patient information in medical multi-disciplinary team meetings, we have developed a system that presents information from different medical systems to be used as a support for the decision process. Based on field studies, we have implemented a high-fidelity prototype on tablet-sized displays, and tested it in a realistic setting. Our evaluation proved that more patient information can efficiently be displayed to all meeting participants, compared to the current situation. Interaction with the information, on the other hand, proved to be a complicated activity that needs careful design considerations; it should ultimately be based on what roles the meeting participants have, and what tasks they should complete. Medical decision-making is a complex area, and conducting interaction design in this area proved complex too. We foresee a great opportunity to improve medical work, by introducing collaborative tools and visualisation of medical data, but it requires that interaction design becomes a natural part of medical work.

  • 37.
    Frånberg, Oskar
    KTH, Skolan för teknik och hälsa (STH), Naturvetenskap och biomedicin, Omgivningsfysiologi.
    Oxygen content in semi-closed rebreathing apparatuses for underwater use: Measurements and modeling2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The present series of unmanned hyperbaric tests were conducted in order to investigate the oxygen fraction variability in semi-closed underwater rebreathing apparatuses. The tested rebreathers were RB80 (Halcyon dive systems, High springs, FL, USA), IS-Mix (Interspiro AB, Stockholm, Sweden), CRABE (Aqua Lung, Carros Cedex, France), and Viper+ (Cobham plc, Davenport, IA, USA). The tests were conducted using a catalytically based propene combusting metabolic simulator. The metabolic simulator connected to a breathing simulator, both placed inside a hyperbaric pressure chamber, was first tested to demonstrate its usefulness to simulate human respiration in a hyperbaric situation. Following this the metabolic simulator was shown to be a useful tool in accident investigations as well as to assess the impact of different engineering designs and physiological variables on the oxygen content in the gas delivered to the diver by the rebreathing apparatuses. A multi-compartment model of the oxygen fractions was developed and compared to the previously published single-compartment models. The root mean squared error (RMSE) of the multi-compartment model was smaller than the RMSE for the single-compartment model, showing its usefulness to estimate the impact of different designs and physiological variables on the inspired oxygen fraction.

  • 38.
    Frånberg, Oskar
    et al.
    KTH, Skolan för teknik och hälsa (STH), Naturvetenskap och biomedicin, Omgivningsfysiologi.
    Gennser, Mikael
    KTH, Skolan för teknik och hälsa (STH), Naturvetenskap och biomedicin, Omgivningsfysiologi.
    Modeling a demand constant volume ratio exhaust and a self-mixing constant oxygen injection semi-closed rebreatherManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Unmanned tests of two types of gas dosage techniques for semi-closed underwater rebreathing apparatuses were carried out with a metabolic simulator in a water filled pressure chamber. Tests were conducted over a wide range of tidal volumes (0.5-3 L), respiratory frequencies (5-25 min-1), and oxygen consumptions (0.5-4 L/min), as well as with changing chamber pressures from 100 kPa to 920 kPa. Two models were set up, one single compartment model and one model assuming multiple serial compartments. Both models seem to have about the same level of accuracy at predicting the inspired oxygen levels at pressure, but the surface tests seem to favor the serial compartments model.

  • 39.
    Gasser, Thomas Christian
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.).
    Aorta2017Ingår i: Biomechanics of Living Organs: Hyperelastic Constitutive Laws for Finite Element Modeling, Elsevier, 2017, s. 169-191Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The aorta is a dynamic structure that is able to maintain conditions for optimal mechanical operation through the continuous turnover of its internal structure. The aorta's properties are critical to the entire cardiovascular system, and the study of its biomechanics may help us to better understand the role of tissue stress and strain in aortic aging and pathology, help to optimize medical devices, and improve therapeutic and diagnostic methods that are currently used in clinics. The present chapter reviews aortic wall histology and morphology in relation to its key mechanical properties. Specifically, the biomechanical role of cells (endothelial cells, smooth muscle cells, fibroblasts, etc.), as well as the extracellular matrix components (elastin, collagen, proteoglycans, water, etc.), will be discussed. Then this information is related to reported constitutive descriptions for aortic tissues. The focus is on histo-mechanical approaches and modeling frames, related to hyperelasticity as well as a superposition of fiber contributions according to a general theory of fibrous connective tissue. Concluding remarks relate to open problems in aorta biomechanics, such as uncertainty and variability of input information. Remarks are also made on the admissible degree of complexity in aortic simulations, in the context of such uncertainties.

  • 40.
    Gavefalk, Sofia
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekonomi och organisation (Inst.), Entreprenörskap och Innovation.
    Widén, Ludwig
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekonomi och organisation (Inst.), Entreprenörskap och Innovation.
    International market selection: Assessing opportunities in the European Union for a mHealth consumer medical device start-up2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    To date, there are no existing models for evaluating foreign markets, adapted to mobile health (mHealth) consumer medical device (CMD) start-ups seeking to launch their products or services in new countries. This calls for the development of a suitable international market selection (IMS) model that captures the complexity of and opportunities for mHealth. mHealth is a sub-segment of electronic health (eHealth), which furthermore is part of the wider phenomenon of digital health. mHealth covers medical and public health practice supported by mobile devices.

    This paper proposes a multidimensional IMS model comprising both macro and micro level factors. Our specialized approach integrates tools and theories by a number of researchers and is showcased in the assessment of the European Union (EU) for the mHealth CMD company AdhereBox. AdhereBox is a Swedish start-up that has developed a CMD consisting of a “smart” pillbox and a complementary mobile software application.

    We propose a number of dimensions that should be evaluated when assessing the potential  of the different EU health care markets in regards to mHealth CMD start-ups. Our suggested approach includes factors which are categorized into two groups of parameters: (i) stakeholders (which comprises consumers, providers, payers, distributors and collaborators) and (ii) barriers & enablers (consisting of incentives, reimbursement models, technological infrastructure, regulations and existing solutions).

    In summary, our study identifies critical factors that mHealth CMD start-ups should consider when evaluating foreign markets in an IMS. By applying our IMS model on AdhereBox, we illustrate how our model can be used, its parameters assessed and the interdependencies between these analyzed in order to arrive at a set of recommendations for further market analysis and conclusions on country attractiveness. As such, we believe that our research could provide valuable insights and guidelines for firms within mHealth seeking to expand their business within the EU, as well as for governmental organizations that want to better leverage and stimulate the potentials of a flourishing domestic mHealth ecosystem. 

  • 41.
    Giordano, Chiara
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Neuronik.
    Kleiven, Svein
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Neuronik.
    Evaluation of Axonal Strain as a Predictor for Mild Traumatic Brain Injuries Using Finite Element Modeling2014Ingår i: 58th SAE Stapp Car Crash Conference, STAPP 2014Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Finite element (FE) models are often used to study the biomechanical effects of traumatic brain injury (TBI). Measures based on mechanical responses, such as principal strain or invariants of the strain tensor, are used as a metric to predict the risk of injury. However, the reliability of inferences drawn from these models depends on the correspondence between the mechanical measures and injury data, as well as the establishment of accurate thresholds of tissue injury. In the current study, a validated anisotropic FE model of the human head is used to evaluate the hypothesis that strain in the direction of fibers (axonal strain) is a better predictor of TBI than maximum principal strain (MPS), anisotropic equivalent strain (AESM) and cumulative strain damage measure (CSDM). An analysis of head kinematics-based metrics, such as head injury criterion (HIC) and brain injury criterion (BrIC), is also provided. Logistic regression analysis is employed to compare binary injury data (concussion/no concussion) with continuous strain/kinematics data. The threshold corresponding to 50% of injury probability is determined for each parameter. The predictive power (area under the ROC curve, AUC) is calculated from receiver operating characteristic (ROC) curve analysis. The measure with the highest AUC is considered to be the best predictor of mTBI.Logistic regression shows a statistical correlation between all the mechanical predictors and injury data for different regions of the brain. Peaks of axonal strain have the highest AUC and determine a strain threshold of 0.07 for corpus callosum and 0.15 for the brainstem, in agreement with previously experimentally derived injury thresholds for reversible axonal injury. For a data set of mild TBI from the national football league, the strain in the axonal direction is found to be a better injury predictor than MPS, AESM, CSDM, BrIC and HIC. 

  • 42. Granåsen, G.
    et al.
    Grönlund, C.
    Öhberg, F.
    Lindberg, Frida
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik.
    Karlsson, J. S.
    Comparison between ultrasonic muscle strain and electromyography during an isometric ramp contraction2010Ingår i: World Congress on Medical Physics and Biomedical Engineering, September 7 - 12, 2009, Munich, Germany, Springer Berlin/Heidelberg, 2010, Vol. 25/4, s. 1565-1567Konferensbidrag (Refereegranskat)
    Abstract [en]

    This study aims to explore multi modal relationships between ultrasonic muscle strain and electromyography (EMG). Canonical Correlation Analysis (CCA) is technique which can be used to explore multivariate associations between sets of variables. Multi-channel EMG and a spatial differentiated Tissue Velocity Imaging (TVI)-strain signal was compared from measurements on biceps brachii on eight subjects. A data analysis using CCA was then applied to obtain useful information of the relationship between signals.

  • 43.
    Gutierrez, Elena M
    KTH, Skolan för teknikvetenskap (SCI), Mekanik, Biomekanik. Chalmers University of Technology.
    A new model for diffuse brain injury by rotational acceleration: I model, gross appearance, and astrocytosis2001Ingår i: Journal of Neurotrauma, ISSN 0897-7151, E-ISSN 1557-9042, Vol. 18, nr 3, s. 247-257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rapid head rotation is a major cause of brain damage in automobile crashes and falls. This report details a new model for rotational acceleration about the center of mass of the rabbit head. This allows the study of brain injury without translational acceleration of the head. Impact from a pneumatic cylinder was transferred to the skull surface to cause a half-sine peak acceleration of 2.1 × 105 rad/s2 and 0.96-ms pulse duration. Extensive subarachnoid hemorrhages and small focal bleedings were observed in the brain tissue. A pronounced reactive astrogliosis was found 8-14 days after trauma, both as networks around the focal hemorrhages and more diffusely in several brain regions. Astrocytosis was prominent in the gray matter of the cerebral cortex, layers II-V, and in the granule cell layer and around the axons of the pyramidal neurons in the hippocampus. The nuclei of cranial nerves, such as the hypoglossal and facial nerves, also showed intense astrocytosis. The new model allows study of brain injuries from head rotation in the absence of translational influences.

  • 44.
    Gutierrez Farewik, Elena M
    Chalmers University of Technology, Crash Safety Division.
    A new model for diffuse brain injury by rotational acceleration: II. Effects on extracellular glutamate, intracranial pressure, and neuronal apoptosis2001Ingår i: Journal of Neurotrauma, ISSN 0897-7151, Vol. 18, nr 3, s. 259-73Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study is to monitor excitatory amino acids (EAAs) in the extracellular fluids of the brain and to characterize regional neuronaldamage in a new experimental model for brain injury, in which rabbits were exposed to 180-260 krad/s2 rotational head acceleration. This loading causes extensive subarachnoid hemorrhage, focal tissue bleeding, reactive astrocytosis, and axonal damage. Animals were monitored for intracranial pressure (ICP) and for amino acids in the extracellular fluids. Immunohistochemistry was used to study expression of the gene c-Jun and apoptosis with the terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) technique. Extracellular glutamate, glycine, and taurine increased significantly in the hippocampus within a few hours and remained high after 24 h. Neuronal nuclei in the granule layers of the hippocampus and cerebellum were positive for c-Jun after 24 h. Little immunoreactivity was detected in the cerebral cortex. c-Jun-positive neuronal perikarya and processes were found in granule and pyramidal CA4 layers of the hippocampus and among the Purkinje cells of the cerebellum. Also some microglial cells stained positively for c-Jun. TUNEL reactivity was most intense at 10 days after trauma and was extensive in neurons of the cerebral cortex, hippocampus, and cerebellum. The initial response of the brain after rotationalhead injury involves brain edema after 24 h and an excitotoxic neuronal microenvironment in the first hour, which leads to extensive delayed neuronal cell death by apoptosis necrosis in the cerebral cortex, hippocampus and cerebellum.

  • 45. Gyarmati, P.
    et al.
    Kjellander, C.
    Aust, C.
    Song, Yajing
    KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Ohrmalm, L.
    Giske, C. G.
    Metagenomic analysis of bloodstream infections in patients with acute leukemia and therapy-induced neutropenia2016Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, artikel-id 23532Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Leukemic patients are often immunocompromised due to underlying conditions, comorbidities and the effects of chemotherapy, and thus at risk for developing systemic infections. Bloodstream infection (BSI) is a severe complication in neutropenic patients, and is associated with increased mortality. BSI is routinely diagnosed with blood culture, which only detects culturable pathogens. We analyzed 27 blood samples from 9 patients with acute leukemia and suspected BSI at different time points of their antimicrobial treatment using shotgun metagenomics sequencing in order to detect unculturable and non-bacterial pathogens. Our findings confirm the presence of bacterial, fungal and viral pathogens alongside antimicrobial resistance genes. Decreased white blood cell (WBC) counts were associated with the presence of microbial DNA, and was inversely proportional to the number of sequencing reads. This study could indicate the use of high-throughput sequencing for personalized antimicrobial treatments in BSIs.

  • 46.
    Hagman, Anna
    KTH, Skolan för teknik och hälsa (STH).
    The Knowledge- and Adoption Level of Standards for Technical Interoperability among Providers of Healthcare Information Systems2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Den här uppsatsen var ett utav delresultaten i StandIN, ett initiativ till att ta fram ett gemensamt ramverk med standarder för teknisk interoperabilitet. Den här uppsatsen syftade till att strukturera och analysera information om kunskaps- och tillämpningsnivån för de tilltänkta standarderna.

    Målgruppen var leverantörer av vårdinformationssystem som används i Sveriges landsting och regioner. Informationen samlades in genom en enkät samt semi-strukturerade intervjuer, och lagrades sedan i en Excel-databas. Pivot-tabeller och -diagram skapades för att visualisera kunskaps- och tillämpningsnivån, och resultaten jämfördes sedan med teori om interoperabilitet och standardtillämpning.

    Det var tydligt att kunskapsnivån skilde sig för de olika standarderna. Tillämpningsnivån var generellt sett väldigt låg, bortsett från CCOW och HL7 v2. Minst tillämpade var domänspecifika standarder. Det var också tydligt att centrala leverantörer inte tillämpade samma standarder, vilket troligtvis påverkar de kompletterande systemen.

    Många leverantörer gjorde snarare specifika integrationer, än följde gemensamma standarder. Anledningen var att valet av standarder var för brett, och att den faktiska tillämpningen av standarder inte var konsekvent mellan olika leverantörer. Enligt leverantörerna skulle ett nationellt ramverk med enhetliga och internationella standarder vara en efterlängtad lösning på problemet.

    En fortsättning på denna uppsats är att använda databasen till att göra klusteranalyser för tillämpningsnivån av standarder hos system i olika landsting och regioner. Databasen skulle också kunna användas till att analysera utvecklingen av kunskap och tillämpning över tid.

  • 47.
    Hagman, Anna
    et al.
    KTH, Skolan för teknik och hälsa (STH).
    Riedberg, Sander
    KTH, Skolan för teknik och hälsa (STH).
    Guidelines for smartphone usage in telemedical photography2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The wide usage of smartphones makes them an interesting and potential medical device. Given that smartphone cameras have a sufficiently high quality - some of the medical photography done at health care facilities could be done telemedically and by non-medically educated per- sons. Therefore a research of the quality of the photos taken with smartphone cameras has been done. This thesis presents guidelines regarding how inexperienced persons could take high qualitative medical photos with a smartphone.

    This thesis includes a review of current guidelines within medical photography. A compari- son between two popular smartphones and a professional medical camera has been done - where possibilities and limitations in smartphone cameras have been identified. In order to evaluate the sharpness and the color temperature representation in the photos taken with smartphones, an experiment with realistic lighting and easy accessible color-calibration cards has been done. The execution and the achieved result have formed the basis of the proposed guidelines.

    The result shows that smartphone cameras are of high quality and thereby could be used as a complement to advanced medical camera equipment. With the help of the proposed guidelines inexperienced persons could acquire sufficiently good medical photos, in order to be used as diagnostic material. This thesis provides a foundation for further research and implementation within the area, with the purpose of becoming an important part of the efficiency improvement within the telemedical health care. 

  • 48.
    Halldin, Peter
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Aare, Magnus
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    von Holst, Hans
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Improved helmet design and test methods to reduce rotational induced brain injuries2003Konferensbidrag (Refereegranskat)
    Abstract [en]

    Accidental impacts to the human head are often a combination of translational and rotational accelerations. The most frequent severe brain injuries from accidents are diffuse axonal injury (DAI) and subdural hematoma that both are reported to arise from rotational violence to the head. Most helmet standards used today do only take the translational accelerations into account. It is therefore suggested that an oblique impact test that measures both translational and rotational accelerations should be a complement to the helmet standards used today. This study investigates the potential to reduce the risk for DAI by improving the helmet design by use of an oblique helmet impact test rig. The method used is a detailed finite element (FE) model of the human head. The FE model is used to measure the maximum principal strain in the brain which is suggested as a measurement for the risk to get DAI. The results clearly show the importance of testing a helmet in oblique impacts. Comparing a pure vertical impact with a 45 degree oblique impact with the same initial impact energy shows that the strain in the central parts of the brain is increased with a factor of 6. It is therefore suggested that a future helmet impact standard should include a rotational component so that the helmet is designed for both radial and tangential forces. Such a test method, an oblique impact test, was used to compare two different helmet designs. One helmet was manufactured with the shell glued to the liner and one helmet was designed with a low friction layer between the shell and the liner (MIPS). It was shown that the strain in the FE model of the human head was reduced be 27% comparing the MIPS helmet to the glued helmet design.

  • 49.
    Halldin, Peter
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Aare, Magnus
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    von Holst, Hans
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Reduced risk for DAI by use of a new safety helmet2003Konferensbidrag (Refereegranskat)
    Abstract [en]

    Accidental impacts to the human head are often a combination of translational and rotational accelerations. The most frequent severe brain injuries from accidents are diffuse axonal injury (DAI) and subdural hematoma that both are reported to arise from rotational violence to the head. Most helmet standards used today do only take the translational accelerations into account. It is therefore suggested that an oblique impact test that measures both translational and rotational accelerations should be a complement to the helmet standards used today. This study investigates the potential to reduce the risk for DAI by improving the helmet design by use of an oblique helmet impact test rig. The method used is a detailed finite element (FE) model of the human head. The FE model is used to measure the maximum principal strain in the brain which is suggested as a measurement for the risk to get DAI. The results clearly show the importance of testing a helmet in oblique impacts. Comparing a pure vertical impact with a 45 degree oblique impact with the same initial impact energy shows that the strain in the central parts of the brain is increased with a factor of 6. It is therefore suggested that a future helmet impact standard should include a rotational component so that the helmet is designed for both radial and tangential forces. Such a test method, an oblique impact test, was used to compare two different helmet designs. One helmet was manufactured with the shell glued to the liner and one helmet was designed with a low friction layer between the shell and the liner (MIPS). It was shown that the strain in the FE model of the human head was reduced be 27% comparing the MIPS helmet to the glued helmet design.

  • 50.
    Halldin, Peter
    et al.
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Jakobsson, Lotta
    Chalmers tekniska högskola School of Mechanical Engineering. Institutionen för tillämpad mekanik. .
    Brolin, Karin
    Chalmers tekniska högskola School of Mechanical Engineering. Institutionen för tillämpad mekanik. .
    Palmertz, Camilla
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    von Holst, Hans
    KTH, Skolan för teknik och hälsa (STH), Neuronik (Stängd 20130701).
    Investigations of Conditions that Affect Neck Compression-Flexion Injuries Using Numerical Techniques2000Ingår i: Stapp Car Crash Journal, ISSN 1532-8546Artikel i tidskrift (Refereegranskat)
1234 1 - 50 av 170
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