| 1. |
- Carina, Stenman, 1964-
(författare)
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Standardized ultrasonography with cine-loop documentation : diagnostic variability in liver and kidney examinations
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Ultrasound examination of the abdomen is often a first choice at radiology departments due to the lack of ionizing radiation. For diagnostic accuracy and economic benefits there has been a need for new routines in this area that incorporate the benefits of an radiographer or sonographer performing a multitude of ultrasound examinations following strictly standardized examination protocols and documentation forms made by cine-loops that will give the radiologist access to all relevant information needed for an accurate postexamination diagnosis.Aim: The overall objective of this thesis was to evaluate the diagnostic variability in examinations of the kidneys and liver that use a standardized ultrasound method along with video documentation of the entire examination and off-line review by radiologists. More specifically, we wanted to compare the agreement between readers and between operators.Design and method: This thesis is based on four quantitative studies using standardized protocols for kidney, liver and gallbladder examinations. In paper I, including 64 patients, and paper IV, including 98 patients, the patients were prospectively enrolled and the examinations were retrospectively reviewed. The patients in papers I and IV were examined by one radiographer (sonographer) and one radiologist during the same session. In paper I, findings using the standardized ultrasound method were compared with traditional bedside assessments by a radiologist. In paper IV, the patients were examined using only the standardized method. In paper II, including 98 patients, and in paper III, including 115 patients, the patients were examined by one sonographer using the standardized method and the examinations were reviewed by two or three radiologists.Results: In paper I, no significant systematic differences were found between the findings using the standardized method and the traditional bedside assessment.Paper II showed good intra- and inter-observer agreement between three experienced radiologists when reviewing examinations conducted using the standardized method.In paper III we verified good inter-observer agreement between two radiologists reviewing ultrasound examinations using the standardized technique in patients who had undergone surgery for colorectal cancer. Intravenous contrast was used and the injection of contrast medium increased the visibility of liver lesions.In paper IV, we observed that using a standardized cine-loop technique, there was a slightly better inter-operator agreement than inter-reader agreement.Conclusion: The satisfactory agreement shown in all four studies suggests that the new workflow method using standardized ultrasound examinations and stored cine-loops, performed by a radiographer or sonographer and analyzed off-line by a radiologist, is a promising technique. The results are less affected when a radiologist examiner is replaced by a radiographer or sonographer than when the reviewer is replaced by a different radiologist.
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| 2. |
- Fyrenius, Anna, 1969-
(författare)
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Dynamiskt lärande : En ämnesdidaktisk avhandling om fysiologiska fenomen och läkarstudentens lärande
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is well known that the outcome of teaching and learning in higher education is often unsatisfactory. Earlier studies have shown that medical students often have a surface approach to their studies and that misconceptions of fundamental physiological phenomena are common. The aim of this thesis is to support educational practice in medicine, particularly in medical physiology. The thesis can be categorised as subject matter-specific education research, which means that questions about teaching and learning are closely linked to the subject studied. The researcher should be well acquainted with the subject in question. The subject area dealt with in this thesis is physiological phenomena related to cardiovascular pressure-flow relations.The thesis consists of studies of 3-dimensional intra cardiac pressure-flow phenomena in the heart (studies 1 and 2) and studies of how students conceive of and develop an understanding of physiological phenomena related to blood pressure and blood pressure regulation (studies 3 and 4).Flow in the left atrium as well as inflow-patterns to the left ventricle were studied. The 3-dimensional method elucidates vortical flow phenomena which were previously unknown. The findings could contribute to increasing physicians and technicians understanding of flow phenomena in the diagnosis and assessment of heart disease and to the further development of diagnostic methods. In the studies of learning and understanding of physiological phenomena, the findings point to new aspects of a deep approach to learning, which have to do with the students’ ability to change perspective and adopt a variety of learning strategies to a phenomenon (Moving) versus a tendency to hold on to one explanatory model (Holding). The study also investigates the students’ ability to identify and apply fundamental physiological principles as well as how they conceive of the importance of detailed knowledge for understanding of physiology. The findings point to differences in the students’ conceptions of physiological principles. A problemising approach, which includes not only causally described relations, indicates a more complex conception of physiological phenomena. The study shows aspects of understanding which are seldom assessed in examinations.The findings indicate a connection between the students’ approaches to learning and the quality of their understanding of fundamental physiological principles. In the thesis, teaching interventions are proposed in order to stimulate dynamic learning and a learning environment where students are not afraid to challenge their conceptions in order to acquire a rich and nuanced picture of physiological phenomena.
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| 3. |
- Fyrenius, Anna, et al.
(författare)
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Student approaches to achieving understanding ― Approaches to learning revisited
- 2007
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Ingår i: Studies in Higher Education. - : Informa UK Limited. - 0307-5079 .- 1470-174X. ; 32:2, s. 149-165
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Tidskriftsartikel (refereegranskat)abstract
- This article presents a phenomenographic study that investigates students' approaches to achieving understanding. The results are based on interviews, addressing physiological phenomena, with 16 medical students in a problem-based curriculum. Four approaches—sifting, building, holding and moving—are outlined. The holding and moving approaches describe variations in deep-level processing. The moving approach is characterised by an intention to continuously refine understanding in an open-ended process. The student strives for a change in perspective and deliberately creates actions that are rich in variation and challenge. The holding approach is characterised by an intention to reach a final goal. This is achieved by high degrees of structure and control in the learning act. Understanding is sometimes sealed, 'held on to' and can be threatened by new input and other students' viewpoints. The study also shows how students deal with details when constructing understanding of wholes.
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| 4. |
- Fyrenius, Anna, et al.
(författare)
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Students' conceptions of underlying principles in medical physiology : An interview study of medical students understanding in a PBL curriculum
- 2007
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Ingår i: Advances in Physiology Education. - : American Physiological Society. - 1043-4046 .- 1522-1229. ; 31, s. 364-369
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Tidskriftsartikel (refereegranskat)abstract
- Medical physiology is known to be a complex area where students develop significant errors in conceptual understanding. Students’ knowledge is often bound to situational descriptions rather than underlying principles. This study explores how medical students discern and process underlying principles in physiology. Indepth interviews, where students elaborated on principles related to blood pressure and blood pressure regulation, were carried out with 16 medical students in a problem-based learning curriculum. A qualitative, phenomenographic approach was used, and interviews were audiotaped, transcribed, qualitatively analyzed, and categorized. Four categories were outlined. The underlying principles were conceived as follows: 1) general conditions for body function at a specified time point, 2) transferable phenomena between organ systems and time points, 3) conditionally transferable phenomena between organ systems and time points, and 4) cognitive constructions of limited value in medical physiology. The results offers insights into students’ thinking about underlying principles in physiology and suggest how understanding can be challenged to stimulate deep-level processing of underlying principles rather than situational descriptions of physiology. A complex conception of underlying principles includes an ability to problemize phenomena beyond long causal reasoning chains, which is often rewarded in traditional examinations and tests. Keywords for problemized processing are as follows: comparisons, differences, similarities, conditions, context, relevance, multiple sampling, connections, and dependencies.
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| 5. |
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| 6. |
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| 7. |
- Lundvall, Lise-Lott, 1959-, et al.
(författare)
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How do technical improvements change radiographers’ practice : a practice theory perspective
- 2015
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Ingår i: Radiography. - : Elsevier. - 1078-8174 .- 1532-2831. ; 21:3, s. 231-235
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Technical improvements in medical imaging have led to the replacement of two-plane imaging techniques by multidimensional imaging. How this affects radiographers’ professional practice has not been investigated.Aim: To explore how technical development affects the relations between different actors and their actions in the practice of computed tomography.Method: A qualitative design was used with data collection by open interviews (n=8) and open observations (n=10) of radiographers during their work with computed tomography. Data was first analysed inductively, resulting in seven preliminary codes. The initial analysis was followed by a phase of abduction, in which the preliminary codes were interpreted theoretically through the lens of practice theory. This resulted in four final themes.Result: First theme: Changed materiality makes practical action easier. The actual image production has become practically easier. Second theme: New machines cause conflict between the structural arrangements of the work and the patient’s needs. The time required for the scanner to carry out image production is easy to foresee, but information about the patient’s individual status and needs is missing and this leads to difficulties in giving individual planned care. Third theme: Changing materiality prefigures learning. The different apparatus in use and the continuously changing methods of image production are coconstitutive of the practitioner’s activities and learning. Fourth theme: How the connections between different practices lead to moments of practical reasoning in the radiography process with CT. The practice of image production with computed tomography takes account of patient safety in relation to radiation doses and medical security risks. The different professions in CT practice are interconnected through common material objects such as computers and machines. However, the radiographers, who meet the patients, have to check the accuracy of the planned examination in relation to the clinical observed information about patient safety risks during the examination.
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| 8. |
- Lundvall, Lise-Lott, 1959-, et al.
(författare)
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Professionals' experiences of imaging in the radiography process – A phenomenological approach
- 2014
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Ingår i: Radiography. - : Elsevier. - 1078-8174 .- 1532-2831. ; 20:1, s. 48-52
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Tidskriftsartikel (refereegranskat)abstract
- IntroductionPrevious studies on radiographers' professional work have shown that this practice covers both technology and patient care. How these two competence areas blend together in practice needs to be investigated. The professionals' experiences of their work have not been studied in depth, and there is a need to focus on their experiences of the main features of their practice.The aimTo explore, from the perspective of the radiographer, the general tasks and responsibilities of their work.MethodData were generated through a combination of open interviews with radiographers and observations of their work with Computer Tomography (CT) and Magnetic Resonance Imaging (MRI). The interviews and observations were analysed using an interpretative phenomenological method.ResultRadiographers' professional work with diagnostic imaging, in a Swedish context, can be viewed as a problem-solving process involving judgments and responsibility for obtaining images that can be used for diagnosis. The examination process comprises three phases; planning, producing the images, and evaluation. In the first phase the radiographer makes judgments on adapting the method to the individual patient, and the second phase involves responsibilities and practical skills for image production. In the third phase, the quality of the images is judged in relation to the actual patient and the imaging process itself.ConclusionsRadiographers consider that the main features of their professional work are patient safety aspects and their knowledge and skills regarding how to produce images of optimal quality, in the actual circumstances of each examination.
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| 9. |
- Lundvall, Lise-Lott, 1959-
(författare)
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Radiographers’ professional practice : a Swedish perspective
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The general aim of this thesis was to empirically describe the radiographers’ professional scope in diagnostic imaging from the viewpoint of the practitioners and investigate how technical development affects the relations and actions in this practice.Data was collected by interviews and observations to both studies at the same time with two different aims. Eight radiographers (n=8) were interviewed. The interviews were open in character, were recorded with a digital voice recorder, and transcribed verbatim by the interviewer. The interview guide consisted of four interview questions. The observations of radiographers during their work with Computer Tomography (CT) and Magnetic Resonance Imaging (MRI) were conducted in a middle-sized radiology department in the southern part of Sweden. The observations were ten (n=10) in total.Two different theoretical perspectives were used: phenomenology (Study I) and practice theory perspective (Study II). Data was analysed with a phenomenological method in Study I. In Study II data was firstly analysed inductively, which resulted in seven codes. Secondly, abduction was made by interpretation of these codes from a practice theory perspective. This led to four themes.The findings in Study I display the main aspect of the radiographers’ work with image production. Their general tasks and responsibilities can be viewed as a process with the goal of producing images that can be used for diagnosis purposes. The process has three different phases: planning the examination, production of images, and evaluation of the image quality. The radiographers experience the production of images as their autonomous professional area.The findings in Study II report how technology development affects the relations between different actors and their actions in the practice of Computer Tomography. Four themes were identified; 1) Changed materiality makes the practical action easier. Radiographers’ practica work with image production has become easier when working with CT compared to conventional techniques because the CT usually performs the image production in one scan. 2) Changed machines cause conflict between the arrangements of the work and the patients` needs. It is difficult to plan the examination individually for each patient because of the arrangements of the CT practice, i.e. they have little information about the patient before the examination. 3) Changing materiality prefigures learning. The radiographers describe a need for constant learning activities because of the changing procedures for image production and new modalities for image production. If not achieved it may affect their relations with the patients. 4) How the connections between different practices lead to times when practical reasoning is required in the radiography process with CT. The connections between the different professions in CT practice mainly occur through material arrangements because physically they work in different areas. The external arrangements in CT practice pre-figure actions for securing accurate radiation level and image quality. But the radiographers, who meet the patients, have to critically judge the intended actions in relation to clinical observed data to ensure patient safety.
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| 10. |
- Lundvall, Lise-Lott, 1959-
(författare)
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Radiography in Practice : Work and Learning in Medical Imaging
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Those following the profession of radiographer mainly work in the healthcare sector, with image production in medical imaging or with radiotherapy treatments. Radiographers are responsible for patient care and handling technology in this profession al field. Radiographers’ practice is interesting to study in relation to technical developments and changing conditions for performing professional work.The general aim of this thesis was to empirically explore the main features of radiographers’ work, how advances in tech n ology affect radiographers’ practice, interconnections with other practices and students learn in g in practice on the way to becoming professionals.Methods: Data was collected using interviews and observations (Papers I, II & IV). For Paper III, individual interviews were conducted. Data was analysed using a phenomenological interpretative method (Paper I) and practice theory perspective (Papers II–IV).Findings: Radiographers’ professional work with image production was seen as a process comprising three phases: planning the examination, producing the images, and evaluating the images. During this process, radiographers make judgements to ensure patient safety and adapt the technology in use to the individual patient. When conventional imaging techniques are converted into examinations performed by Computer Tomography, the planning phase of radiographers’ work process becomes more important. Technology improvements also mean that the technical aspects of radiographers’ work with image production are easier to foresee in scheduling examinations. The caring aspects however are difficult to plan for because of little information about the patient before the examination. The professional practices involved in medical imaging interconnect to ensure patient safety through materiality and common tasks and/ or projects. The content and quality of two artefacts, the referral and the image, in these interconnections are important in collaborative work to ensure patient safety within medical imaging. Radiography students learn professional knowing in practice i.e. practice-as-work, practice-as language and practice-as-morality, during their clinical placements through alternating between two modes of participation: either observing and listening or acting by themselves. The students developed knowing in practice if the other practitioners allowed them to alternate between these two modes of participation.Implications: The description of radiographers’ general tasks an d responsibilities in a work process can be used for both educational and professionalization purposes. The identified interconnections between involved professions are useful for quality improvement to secure patient safety. The findings about development of knowing in practice can be used in the planning and evaluation of clinical placements for students.
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| 11. |
- Norén, Bengt, 1955-, et al.
(författare)
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Absolute quantification of human liver metabolite concentrations by localized in vivo 31P NMR spectroscopy in diffuse liver disease
- 2005
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Ingår i: European Radiology. - : Springer Science and Business Media LLC. - 0938-7994 .- 1432-1084. ; 15:1, s. 148-157
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Tidskriftsartikel (refereegranskat)abstract
- Phosphorus-31 NMR spectroscopy using slice selection (DRESS) was used to investigate the absolute concentrations of metabolites in the human liver. Absolute concentrations provide more specific biochemical information compared to spectrum integral ratios. Nine patients with histopathologically proven diffuse liver disease and 12 healthy individuals were examined in a 1.5-T MR scanner (GE Signa LX Echospeed plus). The metabolite concentration quantification procedures included: (1) determination of optimal depth for the in vivo measurements, (2) mapping the detection coil characteristics, (3) calculation of selected slice and liver volume ratios using simple segmentation procedures and (4) spectral analysis in the time domain. The patients had significantly lower concentrations of phosphodiesters (PDE), 6.3±3.9 mM, and ATP-β, 3.6±1.1 mM, (P<0.05) compared with the control group (10.0±4.2 mM and 4.2±0.3 mM, respectively). The concentrations of phosphomonoesters (PME) were higher in the patient group, although this was not significant. Constructing an anabolic charge (AC) based on absolute concentrations, [PME]/([PME] + [PDE]), the patients had a significantly larger AC than the control subjects, 0.29 vs. 0.16 (P<0.005). Absolute concentration measurements of phosphorus metabolites in the liver are feasible using a slice selective sequence, and the technique demonstrates significant differences between patients and healthy subjects.
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| 12. |
- Norén, Bengt, 1955-
(författare)
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Non-Invasive Assessment of Liver Fibrosis with 31P-Magnetic Resonance Spectroscopy and Dynamic Contrast Enhanced Magnetic Resonance Imaging
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The present study aims at demonstrating phosphorus metabolite concentration changes and alterations in uptake/excretion of a hepatocyte specific contrast agent in patients with diffuse - or suspected diffuse - liver disease by applying two non-invasive quantitative MR techniques and to compare the results with histo-pathological findings, with focus on liver fibrosis.In the first study phosphorus-31 MR spectroscopy using slice selection (DRESS) was implemented. Patients with histopathologically proven diffuse liver disease (n = 9) and healthy individuals (n = 12) were examined. The patients had significantly lower concentrations of phosphodiesters (PDE) and ATP compared with controls. Constructing an ‘anabolic charge’ (AC) based on absolute concentrations, [PME] / ([PME] + [PDE]), the patients had a significant larger AC than the control subjects.The MRS technique was then, in a second study, applied on two distinct groups of patients, one group with steatosis and none-to-moderate inflammation (n = 13) and one group with severe fibrosis or cirrhosis (n = 16). A control group (n = 13) was also included. Lower concentrations of PDE and a higher AC were found in the cirrhosis group compared to the control group. Also compared to the steatosis group, the cirrhosis group had lower concentrations of PDE and a higher AC. A significant correlation between fibrosis stage and PDE and fibrosis stage and AC was found. Using an AC cut-off value of 0.27 to discriminate between mild (stage 0-2) and advanced (stage 3-4) fibrosis yielded an AUROC value of 0.78, similar as for discriminating between F0-1 vs. F2-4.Dynamic contrast enhanced MRI (DCE-MRI) was performed prospectively in a third study on 38 patients referred for evaluation of elevated serum alanine aminotransferase (ALT) and/or alkaline phosphatase (ALP) levels. Data were acquired from regions of interest in the liver and spleen by using single-breath-hold symmetrically sampled two-point Dixon 3D images time-series (non-enhanced, arterial and venous portal phase; 3, 10, 20 and 30 min) following a bolus injection of Gd-EOB-DTPA (0.025 mmol/kg). A new quantification procedure for calculation of the ‘hepatocyte specific uptake rate’, KHep, was applied on a two-compartment pharmacokinetic model. Liver-to-spleen contrast ratios (LSC_N) were also calculated. AUROC values of 0.71, 0.80 and 0.78, respectively, were found for KHep, LSC_N10 and LSC_N20 with regard to severe versus mild fibrosis. Significant group differences were found for KHep (borderline), LSC_N10 and LSC_N20.In study four no significant correlation between visual assessments of bile ducts excretion of Gd-EOB-DTPA and histo-pathological grading of fibrosis or the quantified uptake of Gd-EOB-DTPA defined as KHep and LSC_N.In conclusion 31P-MRS and DCE-MRI show promising results for achieving a non-invasive approach in discriminating different levels of fibrosis from each other.
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| 13. |
- Norén, Bengt, 1955-, et al.
(författare)
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Separation of advanced from mild fibrosis in diffuse liver disease using 31P magnetic resonance spectroscopy
- 2008
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Ingår i: European Journal of Radiology. - : Elsevier. - 0720-048X .- 1872-7727. ; 66:2, s. 313-320
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Tidskriftsartikel (refereegranskat)abstract
- 31P-MRS using DRESS was used to compare absolute liver metabolite concentrations (PME, Pi, PDE, γATP, αATP, βATP) in two distinct groups of patients with chronic diffuse liver disorders, one group with steatosis (NAFLD) and none to moderate inflammation (n = 13), and one group with severe fibrosis or cirrhosis (n = 16). All patients underwent liver biopsy and extensive biochemical evaluation. A control group (n = 13) was also included. Absolute concentrations and the anabolic charge, AC = {PME}/({PME} + {PDE}), were calculated.Comparing the control and cirrhosis groups, lower concentrations of PDE (p = 0.025) and a higher AC (p < 0.001) were found in the cirrhosis group. Also compared to the NAFLD group, the cirrhosis group had lower concentrations of PDE (p = 0.01) and a higher AC (p = 0.009). No significant differences were found between the control and NAFLD group. When the MRS findings were related to the fibrosis stage obtained at biopsy, there were significant differences in PDE between stage F0–1 and stage F4 and in AC between stage F0–1 and stage F2–3.Using a PDE concentration of 10.5 mM as a cut-off value to discriminate between mild, F0–2, and advanced, F3–4, fibrosis the sensitivity and specificity were 81% and 69%, respectively. An AC cut-off value of 0.27 showed a sensitivity of 93% and a specificity of 54%.In conclusion, the results suggest that PDE is a marker of liver fibrosis, and that AC is a potentially clinically useful parameter in discriminating mild fibrosis from advanced.
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| 14. |
- Norén, Bengt, et al.
(författare)
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Visual assessment of biliary excretion of Gd-EOB-DTPA in patients with suspected diffuse liver disease–A biopsy-verified prospective study
- 2015
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Ingår i: European Journal of Radiology Open. - : Elsevier BV. - 2352-0477. ; 2, s. 19-25
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To qualitatively evaluate late dynamic contrast phases, 10, 20 and 30. min, after administration of Gd-EOB-DTPA with regard to biliary excretion in patients presenting with elevated liver enzymes without clinical signs of cirrhosis or hepatic decompensation and to compare the visual assessment of contrast agent excretion with histo-pathological fibrosis stage, contrast uptake parameters and blood tests. Methods: 29 patients were prospectively examined using 1.5T MRI. The visually assessed presence or absence of contrast agent for each of five anatomical regions in randomly reviewed time-series was summarized on a four grade scale for each patient. The scores, including a total visual score, were related to the histo-pathological findings, the quantitative contrast agent uptake parameters, expressed as KHep or LSC_N, and blood tests. Results: No relationship between the fibrosis grade or contrast uptake parameters could be established. A negative correlation between the visual assessment and alkaline phosphatase (ALP) was found. Comparing a sub-group of cholestatic patients with fibrosis score and Gd-EOB-DTPA dynamic parameters did not add any additional significant correlation. Conclusions: No correlation between visually assessed biliary excretion of Gd-EOB-DTPA and histo-pathological or contrast uptake parameters was found. A negative correlation between the visual assessment and alkaline phosphatase (ALP) was found.
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| 15. |
- Ragnehed, Mattias, 1976-, et al.
(författare)
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Visual Grading of 2D and 3D fMRI compared to image based descriptive measures
- 2010
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Ingår i: European Radiology. - Berlin / Heidelberg : Springer. - 0938-7994 .- 1432-1084. ; 20:3, s. 714-724
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Tidskriftsartikel (refereegranskat)abstract
- A prerequisite for successful clinical use of functional Magnetic Resonance Imaging (fMRI) is the selection of an appropriate imaging sequence. In this paper, 2D and 3D fMRI sequences were compared using different image quality assessment methods. Descriptive image measures, such as activation volume and temporal signal-to-noise ratio (TSNR), were compared with results from Visual Grading Characteristics (VGC) analysis of the fMRI results. It was found that significant differences in activation volume and TSNR were not directly reflected by differences in VGC scores. The results suggest that better performance on descriptive image measures is not always an indicator of improved diagnostic quality of the fMRI results. In conclusion, in addition to descriptive image measures, it is important to include measures of diagnostic quality when comparing different fMRI data acquisition methods.
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| 16. |
- Silén, Charlotte, et al.
(författare)
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Advanced 3D visualization in student-centred medical education
- 2008
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Ingår i: Medical teacher. - UK : Informa Healthcare. - 0142-159X .- 1466-187X. ; 30:5, s. e115-e124
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Healthcare students have difficulties achieving a conceptual understanding of 3D anatomy and misconceptions about physiological phenomena are persistent and hard to address. 3D visualization has improved the possibilities of facilitating understanding of complex phenomena. A project was carried out in which high quality 3D visualizations using high-resolution CT and MR images from clinical research were developed for educational use. Instead of standard stacks of slices (original or multiplanar reformatted) volume-rendering images in the quicktime VR format that enables students to interact intuitively were included. Based on learning theories underpinning problem based learning, 3D visualizations were implemented in the existing curricula of the medical and physiotherapy programs. The images/films were used in lectures, demonstrations and tutorial sessions. Self-study material was also developed. AIMS: To support learning efficacy by developing and using 3D datasets in regular health care curricula and enhancing the knowledge about possible educational value of 3D visualizations in learning anatomy and physiology. METHOD: Questionnaires were used to investigate the medical and physiotherapy students' opinions about the different formats of visualizations and their learning experiences. RESULTS: The 3D images/films stimulated the students will to understand more and helped them to get insights about biological variations and different organs size, space extent and relation to each other. The virtual dissections gave a clearer picture than ordinary dissections and the possibility to turn structures around was instructive. CONCLUSIONS: 3D visualizations based on authentic, viable material point out a new dimension of learning material in anatomy, physiology and probably also pathophysiology. It was successful to implement 3D images in already existing themes in the educational programs. The results show that deeper knowledge is required about students' interpretation of images/films in relation to learning outcomes. There is also a need for preparations and facilitation principles connected to the use of 3D visualizations.
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| 17. |
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| 18. |
- Stenman, Carina
(författare)
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New workflow method for ultrasound examinations
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Growing demand for ultrasound examinations and higher quality requirements motivate searching for routines combining the diagnostic accuracy of radiologist-performed examinations with the economical advantages of sonographerperformed examinations. One possible approach is to use strictly standardized examination protocols and documentation made by cine-loops that will give the radiologist access to all relevant information after the examination. Ultrasound examinations are usually regarded as observer dependent, but using documentation with cine-loops acquired in a standardized way attempts to reduce this problem.Aims: The aim of study I was to compare a recently introduced routine, combining acquisition by a radiographer, documentation as standardized cine-loops, and review by a radiologist (“standardized method”), with the formerly used routine where the diagnosis is made bed-side by the radiologist (“traditional method”). The aim of study II was to evaluate the intra-observer and inter-observer agreement of the standardized method in ultrasound liver examinations.Material and Methods: In study I there was 64 policlinic patients examining the kidneys ( n = 27) or the gallbladder ( n =37) by both the standardized and the traditional method. The radiologists’ findings of hydronephrosis, tumors, cysts, echogenicity changes, and cortical thickness (in the kidneys), and wall thickness, concrements, and polyps (in the gallbladder) were compared between the methods with respect to agreement as well as systematic differences. In study II 98 out-patients were examined by a radiographer using the standardized method. Three radiologists with 10 – 20 years of experience of ultrasound reviewed the cine-loops retrospectively and independently filled out a predetermined protocol. After 4 weeks, the review was repeated, blinded to the initial reading.Results: Study I showed for the gallbladder examination a median agreement of 97% (86 – 100%; kappa =0.64 – 1.00) and for the kidney examination an agreement of 90% (78 – 100%; kappa = 0.69 – 1.00). There were no significant systematic differences between the two methods. In study II, the intra-observer agreement was highest for concrements in the gallbladder (kappa = 0.91 to 0.96) and lowest when assessing the need for further examination (kappa = 0.38 to 0.64). For increased liver echogenicity, kappa varied between 0.51 and 0.85, and for skip areas between 0.73 and 0.90. The interobserver agreement was also highest for concrements in the gallbladder (kappa = 0.84 to 1.00) and lowest for need for further examination (kappa = -0.12 to 0.46). For most other findings, substantial intra-observer agreement (kappa ≥ 0.61) was found.Conclusion: The satisfactory agreement in study I indicates that the new workflow with ultrasound examinations performed by a radiographer and analyzed off-line by a radiologist is promising. Study II shows a fairly good inter-observer agreement for ultrasound examinations acquired with a standardized technique by an experienced radiographer and reviewed by experienced radiologists. In general, intra-observer agreement was higher than inter-observer agreement.
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| 19. |
- Vavruch, Ludvig
(författare)
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Adolescent Idiopathic Scoliosis : A Deformity in Three Dimensions
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Scoliosis is a complex three-dimensional deformity of the spine. Even though it has been known for centuries, treatment of the deformity has focused on correcting only in the frontal plane. In the last decades, the need for three-dimensional assessment regarding scoliosis has been highlighted to better understand the cause and the principles of treating scoliosis. The overall aim of this dissertation is to provide knowledge to assess scoliosis as a three-dimensional problem.The severity of scoliosis is measured with the Cobb angle from standing radiographs. Computed tomography (CT) examinations are used throughout this thesis. The first paper investigates the difference in Cobb angle measured from standing radiographs and supine CT examinations. The standing radiographs had larger Cobb angles with a mean difference of 11° and a linear correlation between the two examinations from 128 consecutive patients with adolescent idiopathic scoliosis (AIS) planned for surgery.The second paper compares the axial shape of vertebrae in 20 patients with AIS with a reference group. Clear asymmetry was observed in all vertebrae – superior and inferior end vertebrae as well as the apical vertebra – compared with corresponding vertebrae among the reference group. The asymmetry was most pronounced in the apical vertebra. A novel parameter, frontal vertebral body rotation (FVBR), was introduced to describe the internal rotation of the vertebrae in the axial plane.Pelvic incidence (PI) is a measurement of the position of the sacrum in relation to the femoral heads. This is relevant in scoliosis because PI determines the pelvic configuration acting as a foundation to the spine. PI has traditionally been measured from standing radiographs. The third study investigates PI three-dimensionally, based on low-dose CT examinations, in 37 patients with Lenke type 1 or 5 curves compared with a reference group. A significantly higher PI was observed in patients with Lenke type 5 curves compared with the reference group and patients with Lenke type 1 curves.Severe AIS is treated with corrective surgery. Two approaches are available: the predominant posterior approach and the anterior approach. In the fourth paper, these two approaches are evaluated with regard to three-dimensional correction, how well the correction is maintained over a 2-year follow-up and patient-reported outcome measures. Twenty-seven patients treated with the posterior approach and 26 patients treated with the anterior approach, all with Lenke type 1 curves, were included. Fewer vertebrae were fused in the anterior group, but the posterior group had a better correction of the deformity in the frontal plane. No difference was observed regarding three-dimensional correction and patient-reported outcome measures.AIS is truly a complex three-dimensional deformity. More research is needed to fully comprehend the complexity of the scoliotic spine.
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- Wilhelmsson, Niklas, et al.
(författare)
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Phenomenographic study of basic science understanding-senior medical students' conceptions of fatigue
- 2013
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Ingår i: Education for Health. - : The Network:Towards Unity for Health. - 1357-6283 .- 1469-5804. ; 26:3, s. 156-163
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Helping students learn to apply their newly learned basic science knowledge to clinical situations is a long-standing challenge for medical educators. This study aims to describe how medical students' knowledge of the basic sciences is construed toward the end of their medical curriculum, focusing on how senior medical students explain the physiology of a given scenario. Methods A group of final-year medical students from two universities was investigated. Interviews were performed and phenomenographic analysis was used to interpret students' understanding of the physiology underlying the onset of fatigue in an individual on an exercise bicycle.RESULTS: Three categories of description depict the qualitatively different ways the students conceptualized fatigue. A first category depicts well integrated physiological and bio-chemical knowledge characterized by equilibrium and causality. The second category contains conceptions of finite amount of substrate and juxtaposition of physiological concepts that are not fully integrated. The third category exhibits a fragmented understanding of disparate sections of knowledge without integration of basic science and clinical knowledge.DISCUSSION: Distinctive conceptions of fatigue based with varying completeness of students' understanding characterized the three identified categories. The students' conceptions of fatigue were based on varying understanding of how organ systems relate and of the thresholds that determine physiological processes. Medical instruction should focus on making governing steps in biological processes clear and providing opportunity for causal explanations of clinical scenarios containing bio-chemical as well as clinical knowledge. This augments earlier findings by adding descriptions in terms of the subject matter studied about how basic science is applied by students in clinical settings.
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