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Syfte: Att beskriva den organisationsförändring som fem röntgenkliniker i Sverige genomgick i samband med att radiologin digitaliserades. Frågeställningar: Hur förändrades antalet genomförda radiologiska undersökningar och undersökningstyper från tidpunkten två år före digitaliseringen till två, fyra och sex år efter digitaliseringen? Hur förändrades antalet arbetade timmar och fördelningen av arbetade timmar mellan de olika personalkategorierna från tidpunkten två år före digitaliseringen till två, fyra och sex år efter digitaliseringen? Hur förändrades arbetsuppgifterna inom och mellan de olika personalkategorierna på röntgenklinikerna efter digitaliseringen? Hur beskriver personal med en nyckelfunktion genomförandet av digitaliseringen och eventuell förändring av arbetet efter digitaliseringen? Metod: Kvantitativ och kvalitativ metod har använts och kombinerats för att besvara studiens frågeställningar. Fem svenska röntgenkliniker ingick i studien och material avseende produktionsutfall samlades in från respektive röntgenklinik. Totalt intervjuades 22 personer, med tre till sex intervjuer per röntgenklinik. Teoretiska ramverk: För att försöka förstå de positiva fynden, avseende utökade antalet undersökningar och minskning av arbetade timmar, efter digitaliseringen, genomfördes vid en av röntgenklinikerna en fallstudie med ytterligare två frågeställningar: Hur genomfördes digitaliseringen? Hur har uppföljningen vad avser arbetsflöden, genomförandet och förändringar i detalj genomförts efter digitaliseringen? Delar av Bramson m.fl. (2005) perspektiv och Kotter och Cohens (2002) framgångsfaktorer har applicerats vid analysen av det resultatet. Resultat: Samtliga röntgenkliniker uppvisade en liten ökning av antalet radiologiska undersökningar, medan datortomografi- och magnetkameraundersökningarna ökade markant under den studerade tiden. Efter digitaliseringen genomförs således fler komplicerade undersökningar, vilket anses ha medfört en kvalitativt bättre och säkrare diagnosticering. Övriga undersökningstyper uppvisar varierande resultat. Vid tre av röntgenklinikerna minskade den totala arbetade tiden, och vid två ökade den. Antalet arbetade timmar ökade för röntgenläkare och röntgensjuksköterskor, men minskade för sekreterare och undersköterskor under den studerade tiden. Generellt utför röntgenläkarna och röntgensjuksköterskorna fler arbetsuppgifter efter digitaliseringen, och många av de traditionella arbetsuppgifterna för sekreterare och undersköterskor har försvunnit eller tagits över av datorn. Bättre tillgänglighet, förhöjd kvalitet och utökad diagnostik, tydligare arbetslistor som styr arbetsflödet, förbättrad ergonomi och miljö samt samordning med andra har möjliggjorts efter digitaliseringen. Utifrån intervjuerna i fallstudien framkom teman som beskriver: information, superanvändare, utbildning, tydliga arbetsflöden och rutiner, personalbehov och motivation, liksom ett tydligt ledarskap som genomsyrat förändringsprocessen. Dessa teman är, enligt Bramson och Bramson (2005) och Kotter och Cohen (2002), viktiga att beakta för att lyckas med en förändring. Konklusion: Ingen av de intervjuade vill återgå till ett analogt arbetssätt. Digitaliseringen har inneburit att mycket förändrats för de berörda personalkategorierna, men fördelarna anses uppväga nackdelarna. För att lyckas med en förändring bör Bramsons perspektiv och Kotters framgångsfaktorer tas i beaktande. / Background: Since Wilhelm Conrad Röntgen’s discovery of X-rays in 1896, radiology has undergone great changes. In Sweden, the process of digitalisation radiology was initiated in the mid 1990s. Aim: To describe the organisational changes that took place in five radiol- ogy clinics in Sweden in connection with the digitalisation of radiology. Study questions: How did the number and type of radiological examinations change when comparing two years before with two, four and six years after digitalisation? How did the number and distribution of hours worked change among different staff categories when comparing two years before with two, four and six years after digitalisation? How did the duties change after digitalisation within and between different staff categories at the radiology clinics? How do staff members in key positions describe the implementa- tion of digitalisation and any changes in their professional prac- tice after digitalisation? Method: Quantitative and qualitative methods were combined in order to answer the study questions. Five Swedish radiology clinics took part in the study, and production outcome data were gathered from each clinic. A total of 22 individuals were interviewed, with three to six interviews per radiology clinic. In order to gain an understanding of the positive results at one of the radiology clinics in terms of the increased number of exami- nations and reduction in the number of hours worked after digitalization a case study was conducted at this clinic, in which two questions were posed: How was the digitalisation carried out? How were workflow, im- plementation and changes followed up in detail after digitalisation? Ele- ments of Bramson and Bramson ́s (2005) perspectives and Kotter and Cohen’s (2002) success factors were applied. Findings: All radiology clinics had a small increase in the number of radio- logical examinations, while computed tomography and magnetic reso- nance imaging examinations increased significantly during the period un- der investigation. Thus, more complex examinations were carried out post digitalisation, a fact considered to have led to qualitatively better and safer diagnoses. The total working time was reduced at three clinics, while two exhibited an increase. The total number of hours worked increased for radiologists and radiographers but decreased for secretaries and assistant nurses. In general, radiologists and radiographers performed more tasks post digitalisation, and many of the traditional duties of secretaries and assistant nurses were eliminated or taken over by the computer. Digitalisa- tion enabled greater access to radiological images and patient data in addi- tion to improved quality and diagnostics of the radiological examination. Digitalisation also allowed a better-controlled workflow, as well as im- proving ergonomics, the environment and the coordination with other clinics. The case study interviews revealed themes describing: information, super users, education, clear work flows and routines, staff needs and motiva- tion as well as clear leadership throughout the change process. According to Bramson and Kotter, these themes are important for successful change. Conclusion: None of the individuals interviewed wished to return to the analogue mode of working. The digitalisation led to great changes for the different staff categories, with the advantages outweighing the disad- vantages. To succeed with change, Bramson’s perspectives and Kotter’s success factors should be taken into consideration.

Call number: LD2668 .T4 1964 R47 / Master of Science

Digital Imaging Network-Picture Archiving and Communication System (DIN-PACS) has been the cutting edge technology in telemedicine and teleradiology world. It enables sharing and processing of patient data and images in a networked environment. This sharing implies a distributed environment where doctors and other health practitioners do not need to be physically present in the data sources in order to access them. This advantage in itself is a very economical alternative in time and money. Furthermore, digital processing enables doctors and health practitioners to acquire, examine, and even digitally manipulate data (text, images, sound, and videos). A reduced rate of image loss probability and inexpensive and fast image storage further provide attractions to digital imaging network. Until recent years, however, DIN-PACS technologies are implemented in a localized environment only, e.g., within a single hospital or clinic. The need to share and process these data in a wider area environment (e.g., inter-hospital, city-wide, state-wide, nation-wide, or even world-wide environment), especially in teleradiology discipline, prompted the concept Virtual Radiology Environment (VRE). Virtual Radiology Environment enables the networking of multiple DIN-PACS, which requires an integrated network design configured for both clinicians and radiologist needs. This dissertation presents the design specification and a CORBA-based prototype implementation of such environment.

published_or_final_version / Clinical Oncology / Doctoral / Doctor of Philosophy

This dissertation presents a contrast-enhancement algorithm called Artifact-Suppressed Adaptive Histogram Equalization (ASAHE). This algorithm was developed as part of a larger effort to replace the film radiographs currently used in radiology departments with digital images. Among the expected benefits of digital radiology are improved image management and greater diagnostic accuracy. Film radiographs record X-ray transmission data at high spatial resolution, and a wide dynamic range of signal. Current digital radiography systems record an image at reduced spatial resolution and with coarse sampling of the available dynamic range. These reductions have a negative impact on diagnostic accuracy. The contrast-enhancement algorithm presented in this dissertation is designed to boost diagnostic accuracy of radiologists using digital images. The ASAHE algorithm is an extension of an earlier technique called Adaptive Histogram Equalization (AHE). The AHE algorithm is unsuitable for chest radiographs because it over-enhances noise, and introduces boundary artifacts. The modifications incorporated in ASAHE suppress the artifacts and allow processing of chest radiographs. This dissertation describes the psychophysical methods used to evaluate the effects of processing algorithms on human observer performance. An experiment conducted with anthropomorphic phantoms and simulated nodules showed the ASAHE algorithm to be superior for human detection of nodules when compared to a computed radiography system's algorithm that is in current use. An experiment conducted using clinical images demonstrating pneumothoraces (partial lung collapse) indicated no difference in human observer accuracy when ASAHE images were compared to computed radiography images, but greater ease of diagnosis when ASAHE images were used. These results provide evidence to suggest that Artifact-Suppressed Adaptive Histogram Equalization can be effective in increasing diagnostic accuracy and efficiency.

A method is developed for pre-processing projection images for a SPECT brain imaging system. The projection images are recorded by modular gamma cameras that exhibit noisy response before processing. The image acquisition process is modeled so that the mean of the detected gamma-ray emissions is a linear transformation of the actual flux. Two models for detection are examined, one based on independent Poisson distributions and the other based on a multivariate distribution. The Expectation Maximization (EM) algorithm is used to invert the forward model to obtain a Maximum Likelihood estimate of the flux. Simulations using uniform, Gaussian and point flux patterns demonstrated that EM processing recovered improved estimates of these patterns. Processing measured images yielded improved estimates, but also revealed that both forward models are incomplete.

Introduction. The high technology environment such as a radiology and anaesthesia department in a typical health care setting can many times be a frightening environment for children. Children with neurodevelopmental disorders, such as Autism Spectrum Disorder (ASD), have problems with communication and social interaction. They are dependent on routines and can have higher sensitivity to sensory stimuli than other children. These children are one group who constitutes special challenges in reducing anxiety and creating participation in a high technology environment. This can make them prone to frightening encounters in health care settings if not cared for with special consideration. Aim: The overall aim of this thesis was to audit and enhance the care of children in a high technology environment in the health care system with a focus on children with Autism Spectrum Disorder. Methods: A descriptive design was used with both qualitative and quantitative methods. In Study I, 32 nurse anaesthetists were interviewed to explore the actions and experiences of caring for children in a high technology environment using a qualitative method, known as the Critical Incident Technique (CIT). In the two following studies (Study II, III) a cross-sectional design was used and two national surveys were performed to obtain knowledge on the status in Sweden regarding the care of children with ASD in high technology environments. Sixty-eight anaesthesia departments, 38 paediatric departments and 86 radiology departments responded to the survey. Descriptive statistic was used for the answers apart from the comments part of the questionnaire where qualitative content analysis was used. Due to the limited existence of guidelines in these environments, the creation ofevidence-based guidelines was performed in Study IV, using a Delphi method. The Delphi study was based on information gleaned from the previous studies and from the literature, and 21 experts identified in Study II and III were the expert panel developing the guidelines. Result: Nurses identified children with special needs such as children with ASD as a vulnerable group in a high technology environment (Study I). Seven departments in the anaesthesia context had guidelines for caring for children with ASD in the perioperative context. In the other departments, the care of children with ASD was dependent on the knowledge of the nurse presently working there (Study II). None of the radiology departments in Sweden had guidelines on how to care for children with ASD going through a radiographic examination without anaesthesia (Study III). As a result of Study I, II and III, the need for structured guidelines for caring for children with ASD in a high technology context was identified and a set of guidelines and a checklist was created. The guidelines relate to the organisational structure for the care of children with deficits in social interaction, communication, sensory sensitivity and dependence on routines. The checklist relates to gleaning information about the specific child to be able to give person-centred care based on the specific characteristic of the child (Study IV). Conclusion: Nurses working in a high technology environment in health care have diverse experiences of preventing anxiety in children with ASD coming for a challenging procedure. There are a limited number of evidence-based guidelines to decrease anxiety and to create participation in this group ofchildren. Evidence-based guidelines were created as a tool for enhancing person-centred care in a high technology environment for this group of children. The fact that several problems are assembled under one disorder makes ASD a useful condition to have as a basis for formulating national guidelines. Guidelines that cater for the care of children with ASD in a high technology environment using a person-centred approach may also extend to the care for children with other neurodevelopmental disorders that exhibit some of the same problems as children with ASD.

Zielsetzung: Die Chronisch-Rekurrierende Multifokale Osteomyelitis/Chronische Nicht-bakterielle Osteitis (CRMO/CNO) ist eine seltene auto-inflammatorische Erkrankung, deren typische Symptome starke Knochenschmerzen und lokale Schwellungen sind. Da die Ursachen muskuloskelettaler Beschwerden bei Kindern und Heranwachsenden vielfältig sein können, ist die differentialdiagnostische Unterscheidung einer CRMO/CNO von anderen Erkrankungen, unspezifischen Schmerzen oder einer malignen Grunderkrankung als Quelle der Symptome schwierig. Neue Techniken wie die diffusionsgewichtete Bildgebung (DWI) in der Magnetresonanztomographie (MRT) erlauben Rückschlüsse auf die Gewebestruktur und können in bestimmten Fällen eine Unterscheidung zwischen entzündlichen und malignen Prozessen vereinfachen. Ziel dieser Studie war es daher, die Sichtbarkeit von CRMO-/CNO-Läsionen mittels der DWI-Ganzkörperbildgebung zu evaluieren und den potentiellen klinischen Wert zu untersuchen. Material und Methoden: Sechzehn Patienten mit bekannter CRMO/CNO wurden bei 3 Tesla untersucht. Das Untersuchungsprotokoll beinhaltete u. a. 2D Short Tau Inversion Recovery (STIR) und diffusionsgewichtete Sequenzen in axialer Schichtführung. Die Sichtbarkeit von Läsionen in der DWI und der STIR wurde von 2 Auswertern im Konsensus evaluiert. Für alle Läsionen und in der korrespondierenden Referenzlokalisation wurden der Apparent Diffusion Coefficient (ADC) ermittelt. Ergebnisse: Insgesamt wurden 33 Läsionen eingeschlossen (durchschnittlich 2 Läsionen pro Patient), die sowohl in der STIR als auch in der DWI sichtbar waren. Diese waren vornehmlich in den langen Röhrenknochen lokalisiert. Der mittlere ADC-Wert in Läsionen betrug 1283 mm2/s und war somit signifikant höher als in der Referenzregion, hier betrug der mittlere ADC 782 mm2/s. Im ADCVerhältnis (Läsion vs. Referenzregion) zeigten 82 % der Läsionen eine relative Signalintensitätssteigerung um mehr als 10 %, und 76 % (25 Läsionen) zeigten eine Intensitätssteigerung von mehr als 15 %. Der mittlere relative Signalintensitätsanstieg betrug 69 %. Schlussfolgerung: Diese Studie zeigt, dass die diffusionsgewichtete Ganzkörperbildgebung bei 3 Tesla zuverlässig bei Kindern durchgeführt werden kann. Die ADC-Werte waren in CRMO-/CNO-Läsionen im Vergleich zur Referenzregion signifikant erhöht. Daher wird die Ganzkörperbildgebung in Kombination mit klinischen Angaben von uns als vielversprechende Methode angesehen, um benigne inflammatorische Prozesse anhand der ADC-Werte von bestimmten Malignitäten zu unterscheiden.