Sepsis (blodförgiftning) är ett allvarligt tillstånd och behöver en snabb diagnos som fastställs genom blodprov. Blodprov från hela Stockholms Län skickas till Karolinska Universitetslaboratoriet (KUL) för analys, där biomedicinska analytiker och läkare fastställer arten på infektionen och beslutar vilken antibiotikabehandling är optimal. Målet med arbetet var att identifiera eventuella problem som skapar flaskhalsar hos Klinisk Mikrobiologi i Solna som är en del av KUL. Därefter skulle lösningsförslag framföras och möjligheten att införa blodprover i ett nytt automatiskt system, BD Kiestra Total Lab Automation undersökas. Verksamhetskedjan för laboratoriet analyserades genom observationer och läsning av metodbeskrivningar. Utifrån verksamhetsanalysen identifierades sedan problem. En utbildning med BD Kiestra TLA gav en översikt av hur systemet fungerar samt fördelarna med att använda det. Genom litteraturstudier samt öppna intervjuer kunde förslag på lösningar och förbättringar framföras. Resultaten behandlar de lösningsförslagen för de identifierade problemen, och sammanfattas i en tabell. BD Kiestra TLA behandlades separat med en systembeskrivning, följt av de problem som finns för införandet av blodprov och hur dessa problem kan lösas. / Sepsis (blood poisoning) is a serious affliction that requires a fast diagnosis that can be confirmed through blood samples. Blood samples from all of Stockholm County are sent to Karolinska University Laboratory (KUL) for analysis, where biomedical scientists and medical doctors identify the species of the infection, and decide on the optimum antibiotic treatment. The goal of this assignment was to identify possible problems resulting in bottlenecks at the department of Clinical Microbiology in Solna, which is a part of KUL. Afterwards possible solutions were presented and possibilities of introducing blood samples into a new automated system, BD Kiestra Total Lab Automation, were investigated. The activity line for the blood sample and the laboratory’s operations were analysed by observation and reading of work instructions. The problems were identified through the operational analysis. A course for the BD Kiestra TLA was attended to give an overview of the system and what benefits it gives. The proposed solutions and improvements were formed through literary studies and open interviews. The results present the proposed solutions to the problems, and are summarized in a table. The BD Kiestra TLA was discussed separately with a description of the system, followed by the problems preventing the introduction of blood samples and how these problems can be solved.

Computer Aided Detection (CAD) systems are expecting to gain significant importance in terms of reducing the work load of radiologists and enabling the large screening programs. A large share of CAD systems are based on learning from examples, to enables the decision making between the images with or without disease. Images are simplified to numerical descriptors (features vectors) and the system is trained with these features. The common practical problem with CAD systems is training the system with a data from a specific source and testing it on a data from a different source; the variations between sources usually affect the CAD system function. The possible solutions for this problem are (1) normalizing images to make them look more equal, (2) choosing less variation sensitive features and (3) modifying the classifier so that it classifies the data from different sources more accurately. In this project the effect of image variations on the developed CAD system on chest radio graphs for Tuberculosis is studied at Diagnostic Image Analysis Group. Tuberculosis is one of the major healthcare problems in some parts of the world (1.3 million deaths in 2007) [1]. Although the system has a great performance on the train and test data from the same source, using different sub dataset for training and testing the system does not lead to the same result. To limit the effect of image variation of the CAD systems three different approaches are applied for normalizing the images: (1) Simple normalization, (2) local normalization and (3) multi band local normalization. All three approaches enhance the performance of the system in case of various sub datasets for training and testing purposes. According to the improvement achieved by applying normalization it is suggested as a solution for the stated problem above. Although the outcome of this study has satisfactory result, there is always room for further investigations and studies; in specific testing different approaches for finding less variation sensitive features and modifying the classification procedure to a more variation tolerant process.

Shear wave elastography is a medical imaging modality in which tissue elasticity is estimated by measuring the speed of ultrasound-induced shear waves. This study aimed to implement four shear wave generating pushes and compare their performance according to chosen metrics. The focused push, unfocused push, unfocused comb push and line push were implemented on a Verasonics ultrasound system and tested on a polyvinyl alcohol phantom. Shear wave propagation was imaged using angle-compounded ultrafast imaging. Axial particle velocities were estimated using a 2D autocorrelator and then cross-correlated to obtain local shear wave speed estimates. The focused push and line push were found to generate shear waves with 1--3 times higher peak axial particle velocity, implying better signal-to-noise ratios. The focused push, unfocused push and line push were found to exhibit areas 7 mm wide around the pushing beams in which shear wave speed cannot be estimated, whereas the unfocused comb push has no such blind area.

Quartz Crystal Microbalance (QCM) is a sensitive and effective technique to analyze mass changes at the interface between a solid material and a liquid environment. In this Master thesis, QCM was employed for evaluating the interactions between selected degradable polymers and nanodiamond particles (nDP), fibronectin and the growth factor BMP-2.   Many parameters must be adapted to allow QCM measurements involving degradable polymers. These parameters were then tailored to allow QCM measurements with PLA, poly(LLA-co-CL), poly(TMC-D-LA) and PS.   Moreover, QCM provides quantitative measurements of protein adsorption on degradable polymers. The behavior of PLA and poly(LLA-co-CL) was further evaluated and compared with respect to protein adsorption. This behavior was demonstrated to be different for the two polymers considered and to be dependent on protein concentration in solution.   Eventually, exploiting QCM it was also possible to assess the relationship between nDP and the adsorption of fibronectin and BMP-2 onto PLA and poly(LLA-co-CL).

Accidents related to medical devices are a worldwide problem and result in many deaths each year. It affects patients, relatives, health care workers and society. Due to the complexity of intensive care units (ICUs), such accidents lead to particularly serious consequences. The aim of this thesis was to identify patient safety aspects at ICUs in public and private hospitals in Bangladesh, in order to provide a basis for improving the quality of performance of devices as well as personnel, care and cost effectiveness. The objectives were to a)      compare the conditions of medical devices at ICUs in private and public hospitals, b)      increase understanding of errors, risks and accidents related to medical devices, c)      study reporting systems and communication between staff at ICUs and d)      find ways to minimize hazards related to medical equipment to ensure effective and safe use of devices. Data was collected through interviews during field visits to six hospitals in Dhaka, Bangladesh. Interviews were held with the chiefs of the ICUs, physicians, nurses and technicians. It was noticed that the admission fees to the public hospitals were lower and had more limited resources. Differences between public and private hospitals could be seen in the aspects of finance, the existence of a Biomedical Engineering Department, maintenance and calibration of medical equipment, further education of staff, working environment and infection control. The reporting systems for adverse events and communication about patients’ conditions between coworkers were weak at all hospitals. The procurement process was lengthy at all hospitals. Access to disposable items was limited at several hospitals. The lower admission fee at the government hospitals results in the patients of these hospitals often having a lower income and status, thus less inclined to be critical of the received care. A number of suggestions have been proposed in order to improve the work in the ICU. These include a)      following up rules made by the authorities to ensure they are implemented at each hospital, b)      increasing documentation of malfunctioning devices and adverse events, c)      nurses and physicians taking part in the procurement process, d)      establishing a Biomedical Engineering Department at all hospitals, e)      organizing workshops for health care workers, f)       developing biomedical products adapted for multiple time use and with less need for calibration, g)      providing more education for health care workers in infection control, management of specific devices, solutions to common technical problems, patient safety and user safety, for example using Information and Communication Technology tools (audio and audiovisual material) and discussion platforms as well as h)      constructing an internet forum for consultation on the abovementioned subjects for technicians. / Olyckor relaterade till medicinteknisk utrustning är ett globalt problem som leder till många dödsfall varje år. Det påverkar patienter, anhöriga, sjukvårdspersonal och samhället. Den komplexa miljön på intensivvårdsavdelningar gör att olyckorna leder till allvarliga konsekvenser. Uppsatsen syftade till att identifiera patientsäkerhetsaspekter på intensivvårdsavdelningar i Bangladesh för att skapa en grund för prestandaförbättring, både gällande utrustning och gällande personal. Det ska också öka vård- och konstandseffektiviteten. Målet uppnåddes genom att a)      jämföra användandemiljön för medicinteknisk utrustning på intensivvårdsavdelningar på statliga och privata sjukhus, b)      öka förståelsen för fel, risker och olyckor relaterade till medicinteknisk utrustning, c)      studera rapporteringssystem samt kommunikation mellan personal på intensivvårdsavdelningar och d)      hitta sätt att minimera faror relaterade till medicinteknisk utrustning för att försäkra en effektiv och säker användning av utrustningen. Data samlades in genom intervjuer under en fältstudie på sex sjukhus i Dhaka, Bangladesh. Intervjuer hölls med cheferna på intensivvårdsavdelningarna, läkare, sjuksköterskor och tekniker. Det upptäcktes att patientavgiften på de statliga sjukhusen var lägre och resurserna var mer begränsade. Skillnader mellan statliga och privata sjukhus kunde ses inom ekonomiska resurser, förekomsten av medicintekniskavdelning, underhåll och kalibrering av medicinteknisk utrustning, vidareutbildning av personal, arbetsmiljö och infektionskontroll. Rapporteringssystemen för olyckor samt kommunikationen om patienters tillstånd mellan medarbetare var bristfällig på alla sjukhus. Upphandlingsprocesserna av ny medicintekniskutrustning var lång på alla sjukhus. Tillgången på engångsartiklar var begränsad på flera utav sjukhusen. Den lägre avgiften på de statliga sjukhusen resulterar i att patienterna på dessa sjukhus ofta har lägre inkomst samt status i samhället och är därför mindre benägna att vara kritiska till den mottagna vården. Ett antal ändringar föreslogs för att förbättra arbetet på intensivvårdsavdelningarna. Dessa inkluderar att a)      följa upp de av myndigheterna satta reglerna för att försäkra att de är implementerade på varje sjukhus, b)      öka dokumentationen av icke fungerande utrustning tillika olyckor, c)      sjuksköterskor och läkare skall delta i upphandlingsprocesserna, d)      starta medicintekniska avdelningar på alla sjukhus, e)      organisera workshops för vårdpersonal, f)       utveckla medicintekniska produkter som är anpassade för att användas flera gånger och som behöver kalibreras mer sällan, g)      ge mer utbildning till sjukvårdspersonal om infektionskontroll, hantering av specifika maskiner, lösningar till vanligt förekommande tekniska problem, patientsäkerhet och användarsäkerhet till exempel genom att använda information- och kommunikationsteknik-verktyg (audio och audiovisuellt material) och diskussionsplattformar samt h)      konstruera ett internetforum där tekniker kan få konsultation angående ovannämnda ämnen. / To develop patient safety system to improve the safety and quality of patient care at the Intensive Care Units

This thesis aims to implement a system called SafeWalk to help visually impaired people to sense obstacles in their path and provide them with more independence and more effortless life routines without any external help. SafeWalk is a low power consuming system designed to replace the daily used white cane. It consists of sensors, a buzzer, a vibrating motor, and a software application. The system will be installed on the user's shoe. It detects the objects in front of the user using an Ultrasonic sensor that measures the distance to the targeted object by transmitting sound waves. This will produce vibration in the shoe and causes the buzzer to start playing when the object gets closer. Similarly, using the provided application, signals will be received in the user's smartphone, which will begin to vibrate when the object is detected. The system works just as planned. The final prototype senses objects in the walking path very well. The connection to the app was strong and never disconnected while in use. The phone vibrates stronger if an object on the ground gets closer; if there is an object in the air, the buzzer and vibrator signal the user.

Continuous improvement of image quality is one of the priorities in medical imaging. Therefore, development of a simulation tool allowing to generate realistic images would be of great value to understand better the impact of the components on the image quality metrics and to choose imaging set-ups or new design features to optimize output of existing systems and to prototype new ones and to formalize the link between objective and subjective image quality metrics. Therefore, the purpose of this project, was to contribute to adaptation and validation of an existing simulator for simulation of C-arm X-ray imaging. Firstly, the study of the existing simulation tool was performed to choose further development axes. Afterwards, preliminary estimations of simulation complexity by evaluating the number of photons for a given imaging examination were performed. Previous studies[1] showed the determining impact of focal spot on imaging performance (reducing the limiting spatial frequency in common examination conditions) of X-ray interventional imaging systems.  Therefore, the work focused on the improvements of source model, in particular realistic focal spot was defined and simulations of images with close-to-real sharpness were performed and compared to experimentally acquired images. Finally, a part of this project was dedicated to scatter study. An experimental set-up and "scatter map" analysis were designed to determine the scatter evolution as function of imaging field-of-view.  First simulations were also performed. [1] Samei, E., Ranger, N., MacKenzie, A., Honey, I., Dobbins, J. and Ravin, C. (2008). Detector or System? Extending the Concept of Detective Quantum Efficiency to Characterize the Performance of Digital Radiographic Imaging Systems 1. Radiology, 249(3), pp.926-937.

Diabetes has gained growing attendance as one of the key non communicable diseases (NCD) with the World Health Organization identifying it as the focus of the World Health Day 2016. It is reported that more than 420 million people suffer from diabetes, a number predicted to rise in the coming years. This report forms part of a broader, long term focus project that aims to establish a systems approach to type 2 diabetes (T2D), the variant that accounts for more than 90% of reported diabetes cases. The broader project objectives are to identify possible biomarkers for the onset and the progression of T2D as a precursor to enable potential future approaches to delay onset, or even reverse disease states, via active bio-compounds and/or establishment of beneficial nutritional patterns. The 6-month master’s work reported here is sub-project that focused specifically on cell level vesicle trafficking processes. These processes are believed to be crucial in understanding the formation amyloid plaques, which compromise or kill the insulin secreting beta cells. Up until now, there has been a lack of appropriate experimental techniques to directly observe this process in live cells.  Hence we have developed 2 new techniques: (i)               a method of imaging the actin and tubulin network reorganization during exocytosis of the insulin containing granules while exploring novel ways of characterizing the network. (ii)             a method of imaging the granules themselves and using particle tracking microrheology to analyze their movement patterns during stimulation with glucose. These new techniques open the door to follow up experiments which would allow development of a cell scale mathematical model or simulation correlating short term glucose dynamics to risk of amyloid plaque formation and T2D.

The purpose of the thesis was to analyze and evaluate the head injuries due to a striking in a boxing match by LS-DYNA. A simplified arm model was built up and was equipped with three segments which were linked with two spherical joints. The strain-stress curves of the boxing glove foam and glove leather were measured in the Neuronic Lab in School of Technology and Health, KTH. The dimension and weight of the model was also set as adjustable to fulfill various requirements in different cases. Then a method was developed to facilitate the simulation. Finally, 39 video clips from the database were processed and the 13 cases were chosen to test the method and to perform the simulations. Additionally, the reliability of the model was assessed by comparing the outcome of the simulations with the results of the visual analysis from a previous study. The outcome showed that the model was able to restore the scenario from the videos both quantitatively and qualitatively, but it also suggest a high sensitivity of the model to the data artifacts from the video analysis. Interpretations and suggestions for the future work were also discussed.

Personalen på akutmottagningen vid Karolinska Universitetssjukhuset Solna har under de senaste åren känt av en högre arbetsbelastning trots att antalet patienter under senare år inte ökat. Karolinska Universitetssjukhuset har inte någon metod för att analysera resursbehovet hos olika patientgrupper och skillnaden mellan dessa. Projektet handlade därmed om att ge Karolinska Universitetssjukhuset en bättre förståelse för olika patienters resursbehov i form av en resursåtgångsmodell. Denna modell skapades genom diskussioner med personal och analys av data från Karolinskas interna datalager, Karda. Från detta skapades en patientgruppsuppdelning med syfte att gruppera patienter med likartade resursbehov. Tidsstudier samt enkäter genomfördes och sammanställdes på akutmottagningen för att framta viktig information. Analys av resultaten som erhölls tyder på att patienter under de senare åren har blivit mer sjuka och därmed mer resurskrävande för sjukhuset. En resursåtgångsmodell skapades vilken kan analysera och jämföra patienters vårdtyngd med varandra via tre parametrar; prioritet och övervakning, vistelsetid och jourtillägg. Dock kan inte denna modell i nuläget analysera alla parametrar samtidigt, utan endast var för sig. För att kunna analysera parametrarna samtidigt behöver modellen och beräkningarna revideras. Detta skulle kunna vara ett fortsatt arbete inom området. / The staff of the emergency department at Karolinska Universitetssjukhuset Solna has in recent years experienced a higher workload, although the number of patients has not increased. Karolinska Universitetssjukhuset do not possess a set method to analyze the resource needs of different patient groups, and the difference between them. The project would thus give Karolinska Universitetssjukhuset a better understanding of different patients' resource needs in the form of a resource consumption model. This model was created through discussions with staff and analysis of data from Karolinska's internal data warehouse, Karda. From this a patient group distribution was created with the aim of grouping patients with similar resource needs. Time studies and surveys were conducted and compiled at the emergency department to generate important information. Analysis of the results obtained suggests that patients have, in recent years, become more ill and therefore more costly for the hospital. A resource consumption model has been created which can analyze and compare the patients' burden of care with one another by three parameters. These are priority and monitoring, period of residence and on-call salary increment. However, this model is not currently able to analyze all parameters simultaneously, only individually. In order to analyze parameters simultaneously the model and calculations would need to be revised. This could be a continuous study for further work in this specific area.