Introduktion: Cystisk fibros (CF) är en medfödd sjukdom som gör slemmet i kroppen mycket tjockare och segare än vanligt. Sjukdomen drabbar främst lungorna och mag- tarmkanalen. Patientgruppen genomgår upprepade radiologiska undersökningar av lungorna genom hela livet, detta medför en ökad risk för strålinducerad cancer. Syfte: Att sammanställa den aktuella forskningen gällande lungundersökningar med magnetresonanstomografi (MR) och datortomografi (DT) för patienter med cystisk fibros. Metod: Denna studie utfördes som en allmän litteraturöversikt. Elva vetenskapliga artiklar valdes ut, analyserades och sammanställdes. Resultat: DT anses som golden standard för diagnostik av lungorna. Olika MR sekvenser har utvecklats för att matcha kvaliteten hos DT, men något standardprotokoll finns inte idag. Fördelar med MR är att modaliteten både kan visa anatomi och funktion jämfört med DT. Den sämre detaljupplösningen och den längre undersökningstiden anses som nackdelar. Slutsats: MR är ett bättre alternativ än DT som potentiell undersökningsmetod och för uppföljning av sjukdomen för patienter med CF. I dagsläget är DT fortfarande standardundersökningsmetoden, med risk för utveckling av strålningsinducerad cancer.

Röntgen av bröst görs med hjälp av en mammograf och den första mammografen tillverkades 1968. En mammografiundersökning utförs av en röntgensjuksköterska som komprimerar bröstet mellan en platta och en detektor. Röntgensjuksköterskans intention är att verka för varje unik individ, då alla individer har olika mängd vävnad i brösten. Bröstkompressionen vid mammografiundersökningen är komplex och det finns en bristande kunskap om helheten i området. Syfte: Att sammanställa kunskapsläget gällande vilka parametrar som har inverkan på bröstkompression vid mammografiundersökningar. Metod: En allmän litteraturöversikt utfördes. I analysen ingick 12 artiklar. Resultat: Tre kategorier framkom under analysen, dessa var: patientrelaterade egenskaper, självkomprimering och tekniska egenskaper. Kategorin patientrelaterade egenskaper innefattar densitet, brösttjocklek, stråldos, kompressionskraft och kompressionstryck, självkomprimering innehåller artiklar där patienten delvis utför mammografiundersökningen själv och tekniska egenskaper innehåller artiklar som tar upp kompressionsplattor, fabrikat och detektorer. Slutsats: Slutsatsen av denna allmänna litteraturöversikt är att bröstkompressionen har stor betydelse vid mammografiundersökningar och att förbättringsområden finns inom självkomprimering, brösttomosyntes, kompressionskraft och kompressionstryck. Det behövs mer forskning i ämnet.

Introduktion: Ischemisk stroke är en av de vanligaste folksjukdomar och kan leda till funktionsnedsättning och mortalitet. Diagnostisering och tid är faktorer som spelar en avgörande roll inför behandling och prognos av ischemisk stroke. Trots att DT idag anses vara förstahandsval vid diagnostisering, har den lägre sensitivitet än MR att upptäcka ischemi. Även om MR med DWI anses ge ökade möjligheter vid diagnostisering av ischemisk stroke, varierar idag användningen mycket i Sverige. Syfte: Att sammanställa kunskap om diffusionsviktade sekvensers användbarhet inom magnetresonanstomografi för att diagnostisera och behandling av ischemisk stroke. Metod: En allmän litteraturstudie genomfördes i enlighet med Friberg (2017), där tolv artiklar från PubMed och Cinahl with fulltext analyserades och granskades. Resultat: Resultatet visar att DWI har hög sensitivitet att diagnostisera lesioner, men vid vissa fall detekteras inga lesioner trots att patienten har typiska symtom. DWI är även bra på att utvärdera om trombolys är säkert att administrera upp till tolv timmar efter symtomdebut, samt kan användas för att beräkna trombektomins förväntade resultat utifrån lesionens storlek. Slutsats och kliniska implikationer: MR med DWI kan komma att ha en betydande roll i framtiden för att förbättra diagnostisering och behandling av patienter med akut ischemisk stroke. Fler patientgrupper kommer att få möjligheten till behandling som tidigare exkluderades, vilket minskar både dödlighet och funktionsnedsättning. Effektivare protokoll behövs för att införa MR med DWI i en större skala för att diagnostisera patienter med ischemisk stroke, vilket kommer att vara en stor utmaning som kräver fler MR apparater, röntgensjuksköterskor med specialistkompetens, multiprofessionellt arbete och mer forskning.

The substantial advances of coronary CTA have resulted in a boost of use of this new technique in the last several years, which brings a big challenge to radiologists by the increasing number of exams and the large amount of data for each patient. The main goal of this study was to develop a computer tool to facilitate coronary CTA analysis by combining knowledge of medicine and image processing.Firstly, a competing fuzzy connectedness tree algorithm was developed to segment the coronary arteries and extract centerlines for each branch. The new algorithm, which is an extension of the “virtual contrast injection” method, preserves the low density soft tissue around the coronary, which reduces the possibility of introducing false positive stenoses during segmentation.Secondly, this algorithm was implemented in open source software in which multiple visualization techniques were integrated into an intuitive user interface to facilitate user interaction and provide good over¬views of the processing results. Considerable efforts were put on optimizing the computa¬tional speed of the algorithm to meet the clinical requirements.Thirdly, an automatic seeding method, that can automatically remove rib cage and recognize the aortic root, was introduced into the interactive segmentation workflow to further minimize the requirement of user interactivity during post-processing. The automatic procedure is carried out right after the images are received, which saves users time after they open the data. Vessel enhance¬ment and quantitative 2D vessel contour analysis are also included in this new version of the software. In our preliminary experience, visually accurate segmentation results of major branches have been achieved in 74 cases (42 cases reported in paper II and 32 cases in paper III) using our software with limited user interaction. On 128 branches of 32 patients, the average overlap between the centerline created in our software and the manually created reference standard was 96.0%. The average distance between them was 0.38 mm, lower than the mean voxel size. The automatic procedure ran for 3-5 min as a single-thread application in the background. Interactive processing took 3 min in average with the latest version of software. In conclusion, the presented software provides fast and automatic coron¬ary artery segmentation and visualization. The accuracy of the centerline tracking was found to be acceptable when compared to manually created centerlines.

Bakgrund: 18F-FDG-PET/DT är en undersökning som påvisar cellers glukosmetabolism och en viktig metod inom diagnostik. Undersökningen kräver förberedelser som patienten utför på egen hand polikliniskt. Vid missad förberedelse kan undersökningen bli fördröjd eller inställd och ombokad. Det är därför viktigt med tydlig och förståelig information.   Syfte: Syftet med studien var att undersöka hur patienter upplevde informationen inför en 18F-FDG-PET/DT-undersökning och vad som kunde förbättras. Ett ytterligare syfte var att undersöka om det fanns ett samband mellan patientens ålder/kön och upplevelse av information innan undersökning.  Metod: Studien var en empirisk kvantitativ enkätstudie med inslag av kvalitativa data. Enkäten innehöll 9 frågor om patientens upplevelse av information inför undersökningen. Patienter som hade genomgått en 18F-FDG-PET/DT-helkroppsundersökning på en nuklearmedicinsk avdelning inkluderades. Resultat: Studien samlade in 86 besvarade enkäter med totalt 101 tillfrågade. Resultatet visade att 83 patienter var nöjda med informationen men att det finns förbättringspotential. Majoriteten av deltagarna i studien föredrog skriftlig information. Kvalitativa data analyserades och delades in i tre kategorier: nuvarande upplevelser, förbättringspotential och individanpassad information, vilket gav konkreta förslag på vad patienten upplever kan förbättras. Den kvantitativa analysen visade att det inte fanns något samband mellan kön och upplevelse av information, respektive ålder och upplevelse av information.   Slutsats: Studien visade att majoriteten av patienterna som skulle genomgå en 18F-FDG-PET/DT-undersökning var nöjda med informationen i kallelsen och kände sig förberedda inför undersökningen. Det fanns dock förbättringspotential för att ytterligare underlätta patientförberedelserna och resultatet av den här studien kan användas för att optimera informationen innan undersökningen. / Background: 18F-FDG-PET/CT examines cellular glucose metabolism and has a pivotal role in diagnostics. The examination requires preparations the patient must do independently before arrival to the hospital. Not following preparations may result in postponed or canceled examinations. Therefore, it is important to have understandable information. Purpose: The purpose of the study was to research the patient-experience related to the information before a 18F-FDG-PET/CT-examination and potential improvements. An additional purpose was to explore if there was a correlation between gender or age and opinions about the current information before the examination. Method: The study design was an empirical quantitative questionnaire including elements of qualitative data. The survey consisted of 9 questions about the patients experiences considering the information before the examination. Patients who had completed a 18F-FDG-PET/CT at a nuclear medicine department were asked to participate in the study. Results: In total, 101 patients were asked to participate, 86 questionnaires were collected. 83 patients were satisfied with the information and the majority preferred written information. The qualitative data were analyzed and divided into three categories: current experiences, potential improvement and individualized information, which presented factual improvements. The result showed no correlation between gender and experience as well as age and experience about the current information before the examination. Conclusion: The study found that the majority of the 18F-FDG-PET/CT-patients are satisfied with the information and felt prepared for the examination. However, there was room for improvement. The results in this study could be used to optimize the information given before the examination.

Introduktion: Jodbaserade kontrastmedel används på sjukhus som nyttjar en datortomografisk kamera, då dess syfte är att förstärka frisk och sjuk vävnad. Då kontrastmedel används frekvent, är det viktigt att ha rätt dosering. Enligt rekommendationer skall doseringen anpassas beroende på patientens njurvärde (GFR), ålder, vikt och längd. Trots rekommendationerna så använder sjukhus olika doser trots undersökningen gäller en och samma patient. Metod: En enkät distribuerades ut till 49 sjukhus via mejl för att samla in dosanvändning av intravenöst kontrastmedel på en datortomografisk bukundersökning. Ett total av 33 sjukhus medverkade i svarsinsamlingen (67%), som inkluderade 3 universitetssjukhus, 11 länssjukhus, 17 länsdelssjukhus och 2 anonyma sjukhus. Enkäten gjordes via esMaker och innehöll två fiktiva patientfall, och fem frågor gällande sjukhusens datortomografiska kamera, samt deras beräkningssystem av kontrastmedel. Syfte: Undersöka skillnader i kontrastmedelsanvändning vid datortomografiska bukundersökningar. Resultat: Patientfall 1 hade en kontrastmedelsdos mellan 84–120 ml, medan patientfall 2 visade en variation mellan 66–96 ml. aGFR användes hos 52% av sjukhusen för uträkning av kontrastmedel, 27% använde rGFR och 21% använde en kombination av båda. Slutsats: Det finns en skillnad i doseringen av jodkontrastmedel på olika sjukhus runtom i Sverige. / Introduction: Iodine-based contrast agents are used in hospitals equipped with a computed tomographic camera, as their purpose is to enhance both healthy and diseased tissue. As contrast agents are used frequently, it is important to use the correct dosage. According to recommendations, the dosage should be adjusted depending on the patient’s kidney function (GFR), age, weight, and height. Despite the recommendations, hospitals use different doses even though the examination concerns the same patient. Methods: A survey was out to 49 hospitals via email to collect information on the dosage of intravenous contrast agents in computed tomographic abdominal examinations. A total of 33 hospitals participated in the data collection (67%), including 3 university hospitals, 11 district hospitals, 17 county hospitals and 2 anonymous hospitals. The survey was conducted using esMaker and included two fictitious patient cases, and five questions regarding their computed tomographic camera and their calculations system. Objectives: To investigate differences in the usage of contrast agents in computed tomographic abdominal examinations. Results: Patient case 1 had a contrast agents dose ranging from 84–120 ml, while patient case 2 showed a variation between 66–96 ml. Absolute GFR were used in 53% of the hospitals for calculating the contrast agent dosage, 27% used relative GFR, and 21% used a combination of both. Conclusions: There is a variation in the dosage of contrast agents used in different hospitals across Sweden.

Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. The proposed Magnetic Resonance-only Radiotherapy (MR-only RT) work flow allows for the use of MRI as the sole imaging modality in the radiotherapy (RT) treatment planning of cancer. There are, however, issues with geometric distortions inherent with MR image acquisition processes. These distortions result from imperfections in the main magnetic field, nonlinear gradients, as well as field disturbances introduced by the imaged object. In this thesis, we quantified the effect of system related and patient-induced susceptibility geometric distortions on dose distributions for prostate as well as head and neck cancers. Methods to mitigate these distortions were also studied. In Study I, mean worst system related residual distortions of 3.19, 2.52 and 2.08 mm at bandwidths (BW) of 122, 244 and 488 Hz/pixel up to a radial distance of 25 cm from a 3T PET/MR scanner was measured with a large field of view (FoV) phantom. Subsequently, we estimated maximum shifts of 5.8, 2.9 and 1.5 mm due to patient-induced susceptibility distortions. VMAT-optimized treatment plans initially performed on distorted CT (dCT) images and recalculated on real CT datasets resulted in a dose difference of less than 0.5%.  The magnetic susceptibility differences at tissue-metallic,-air and -bone interfaces result in local B0 magnetic field inhomogeneities. The distortion shifts caused by these field inhomogeneities can be reduced by shimming.  Study II aimed to investigate the use of shimming to improve the homogeneity of local  B0 magnetic field which will be beneficial for radiotherapy applications. A shimming simulation based on spherical harmonics modeling was developed. The spinal cord, an organ at risk is surrounded by bone and in close proximity to the lungs may have high susceptibility differences. In this region, mean pixel shifts caused by local B0 field inhomogeneities were reduced from 3.47±1.22 mm to 1.35±0.44 mm and 0.99±0.30 mm using first and second order shimming respectively. This was for a bandwidth of 122 Hz/pixel and an in-plane voxel size of 1×1 mm2.  Also examined in Study II as in Study I was the dosimetric effect of geometric distortions on 21 Head and Neck cancer treatment plans. The dose difference in D50 at the PTV between distorted CT and real CT plans was less than 1.0%. In conclusion, the effect of MR geometric distortions on dose plans was small. Generally, we found patient-induced susceptibility distortions were larger compared with residual system distortions at all delineated structures except the external contour. This information will be relevant when setting margins for treatment volumes and organs at risk.   The current practice of characterizing MR geometric distortions utilizing spatial accuracy phantoms alone may not be enough for an MR-only radiotherapy workflow. Therefore, measures to mitigate patient-induced susceptibility effects in clinical practice such as patient-specific correction algorithms are needed to complement existing distortion reduction methods such as high acquisition bandwidth and shimming.

Bakgrund: I Sverige har alla personer rätt till lika vård. För att kunna utföra sitt arbete krävs en god kommunikation mellan röntgensjuksköterskan och patienten. Kommunikation innefattar verbala- och icke verbala uttryck, som är ytterst essentiellt för arbete inom vården. Genom omdöme, kunskap och noggrannhet måste röntgensjuksköterskan kunna ge adekvat information som berör undersökningen eller behandlingen. Informationen bör anpassas utefter patientens förmåga och vitala tillstånd att tillgodose sig denna. Syfte: Syftet var att sammanfatta faktorer som kan påverka kommunikationen mellan röntgensjuksköterskan och patienten. Metod: Denna studie genomfördes som en allmän litteraturstudie där databaserna PubMed och Cinahl användes. Totalt inkluderades och analyserades 10 artiklar i studien.  Resultat: Studiens resultat sammanfattades i 7 olika faktorer; professionalism, språk, information, hög arbetsbelastning, tid, sjukdom och ångest/rädsla. Alla faktorer kunde förbättra kommunikationen, men också försvåra den. Slutsats: Mer kunskap och medvetande om kommunikation hos röntgensjuksköterskan behövs, samt ett samarbete med kollegor för uppmuntran till kommunikation som är individanpassad. Att sammanfatta dessa faktorer kan hjälpa röntgensjuksköterskan i dennes arbete med kommunikationen till patienten i olika situationer. / Background:In Sweden, all persons are entitled to equal health care. In order for the radiographer to carry out their work, good communication between the radiographer and the patient is required. Communication with both verbal expressions and also body language which is necessary when working in health care. Through judgment, knowledge and accuracy, the radiographer must be able to provide adequate information regarding the examination or treatment.The information should be adapted according to the patient's ability and vital condition to accommodate this. Purpose: The purpose of the thesis was to summarize factors that may affect communication between the radiographer and the patient.Method: In order to achieve this, it was decided to make a qualitative, general literature study using the PubMed and Cinahl databases. A total of 10 articles were selected for the thesis. Results: The results were summarized in 7 different factors; professionalism, language, information, high workload, time, illness and anxiety/fear. All factors could improve communication, but some parts could also make it difficult. Conclusion: More knowledge and awareness of communication skills is necessary for the radiographer, as well as collaboration with colleagues to encouraging individualized communication. Summarizing these factors can help us as radiographer in our work on communicating to the patient in different situations.

Stress has emerged as one of the most important factors to consider in psychiatric diagnoses and has become a common reason for long-term sick leave (LTSL). Roughly 50% of LTSL due to psychiatric diseases are thought to be associated with work-related stress. The demarcation towards major depression is disputed, and no international consensus exists for how to diagnose and rehabilitate these individuals. The Swedish National Board of Health has suggested the term “exhaustion syndrome” to integrate these individuals into stress-related disorders. Prominent features of this syndrome are fatigue, sleeping disorders, and cognitive dysfunction. The cognitive dysfunction may be due to an interaction between personality features, environmental factors, the biological effects of stress hormones, and dysfunction in key brain areas, notably the hippocampus and prefrontal cortex. A consistent feature of chronic stress is activation of the cortisol, or hypothalamic-pituitary-adrenal, axis, which may be linked to cognitive dysfunction. Increased glucocorticoid levels, mainly cortisol in humans, are known to impair memory performance. The aim of this thesis was to investigate whether patients with exhaustion syndrome exhibit specific alterations in an extensive set of biological, psychological and immunological variables. Patients in Study 1 had significant cognitive impairment for specific tasks assumed to tap frontal lobe functioning. In Study 2 anxiety prone, worrying, pessimistic individuals with low executive drive and a persistent personality type were more likely to develop exhaustion syndrome. Decreased reactivity was found on the pituitary level after corticotropin releasing hormone (CRH) in exhaustion syndrome patients. The cortisol/adrenocorticotropic hormone response to CRH was slightly higher in patients compared to controls, indicating increased sensitivity at the adrenal cortex level. No differences were found in hippocampal volume. In Study 3, functional imaging revealed a different pattern of brain activation in working memory tests in patients with exhaustion syndrome compared to healthy individuals and patients with depression. In summary, our data suggests an intimate link between personality and wellbeing, cognitive performance and neuroendocrine dysfunction, in exhaustion syndrome. We thus find similarities with major depression but also distinct differences between the exhaustion syndrome and major depression.

Magnetic resonance imaging (MRI) is one of the most important diagnostic tools of modern healthcare. The signal in medical MRI predominantly originates from water and fat molecules. Separation of the two components into water-only and fat-only images can improve diagnosis, and is the premier non-invasive method for measuring the amount and distribution of fatty tissue. Fat-water imaging (FWI) enables fast fat/water separation by model-based estimation from chemical shift encoded data, such as multi-echo acquisitions. Qualitative FWI is sufficient for visual separation of the components, while quantitative FWI also offers reliable estimates of the fat percentage in each pixel. The major problems of current FWI methods are long acquisition times, long reconstruction times, and reconstruction errors that degrade image quality. In this thesis, existing FWI methods were reviewed, and novel fully automatic methods were developed and evaluated, with a focus on fast 3D image reconstruction. All MRI data was acquired on standard clinical scanners. A triple-echo qualitative FWI method was developed for the specific application of 3D whole-body imaging. The method was compared with two reference methods, and demonstrated superior image quality when evaluated in 39 volunteers. The problem of qualitative FWI by dual-echo data with unconstrained echo times was solved, allowing faster and more flexible image acquisition than conventional FWI. Feasibility of the method was demonstrated in three volunteers and the noise performance was evaluated. Further, a quantitative multi-echo FWI method was developed. The signal separation was based on discrete whole-image optimization. Fast 3D image reconstruction with few reconstruction errors was demonstrated by abdominal imaging of ten volunteers. Lastly, a method was proposed for quantitative mapping of average fatty acid chain length and degree of saturation. The method was validated by imaging different oils, using gas-liquid chromatography (GLC) as the reference. The degree of saturation agreed well with GLC, and feasibility of the method was demonstrated in the thigh of a volunteer. The developed methods have applications in clinical settings, and are already being used in several research projects, including studies of obesity, dietary intervention, and the metabolic syndrome.