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1.	Anesäter, Erik, et al. (författare) The influence of different sizes and types of wound fillers on wound contraction and tissue pressure during negative pressure wound therapy. 2011 Ingår i: International Wound Journal. - 1742-481X. ; 8, s. 336-342 Tidskriftsartikel (refereegranskat)abstract Negative pressure wound therapy (NPWT) contracts the wound and alters the pressure in the tissue of the wound edge, which accelerates wound healing. The aim of this study was to examine the effect of the type (foam or gauze) and size (small or large) of wound filler for NPWT on wound contraction and tissue pressure. Negative pressures between -20 and -160 mmHg were applied to a peripheral porcine wound (n = 8). The pressure in the wound edge tissue was measured at distances of 0·1, 0·5, 1·0 and 2·0 cm from the wound edge and the wound diameter was determined. At 0·1 cm from the wound edge, the tissue pressure decreased when NPWT was applied, whereas at 0·5 cm it increased. Tissue pressure was not affected at 1·0 or 2·0 cm from the wound edge. The tissue pressure, at 0·5 cm from the wound edge, was greater when using a small foam than when using than a large foam. Wound contraction was greater when using a small foam than when using a large foam during NPWT. Gauze resulted in an intermediate wound contraction that was not affected by the size of the gauze filler. The use of a small foam to fill the wound causes considerable wound contraction and may thus be used when maximal mechanical stress and granulation tissue formation are desirable. Gauze or large amounts of foam result in less wound contraction which may be beneficial, for example when NPWT causes pain to the patient.
2.	Anna Karin, Hedström, et al. (författare) The impact of bariatric surgery on disease activity and progression of multiple sclerosis : A nationwide matched cohort study 2022 Ingår i: Multiple Sclerosis Journal. - : Sage Publications. - 1352-4585 .- 1477-0970. ; 28:13, s. 2099-2105 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: Surgical outcomes in patients with multiple sclerosis (MS) following metabolic surgery appear to be similar compared to those of the general bariatric population.OBJECTIVE: To study the impact of metabolic surgery on the clinical course of MS.METHODS: Using data from the Scandinavian Obesity Surgery Registry and the Swedish Multiple Sclerosis register, we compared disease outcomes in 122 cases of MS who had undergone metabolic surgery with those of 122 cases of MS without surgery, matched by a two-staged Propensity score match, including age at disease onset, sex, MS phenotype, body mass index, and preoperative severity of MS as measured by the Expanded Disability Status Scale.RESULTS: The time to 6-month confirmed disability progression during the first five years postbaseline was shorter among the surgical patients (hazard ratio (HR) = 2.31, 95% confidence interval (CI) = 1.09-4.90; p = 0.03). No differences were observed regarding postoperative annual relapse rate (p = 0.24) or time to first postoperative relapse (p = 0.52).CONCLUSION: Although metabolic surgery appears to be a safe and efficient treatment of obesity in patients with MS, the clinical course of the disease might be negatively affected. Long-term nutritional follow-up after surgery and supplementation maintenance are crucial, particularly among those with preoperative deficits.
3.	Bergvall, Erik, et al. (författare) Spline-based cardiac motion tracking using velocity-encoded magnetic resonance imaging. 2008 Ingår i: IEEE Transactions on Medical Imaging. - 1558-254X. ; 27:8, s. 1045-1053 Tidskriftsartikel (refereegranskat)abstract This paper deals with the problem of tracking cardiac motion and deformation using velocity-encoded magnetic resonance imaging. We expand upon an earlier described method and fit a spatiotemporal motion model to measured velocity data. We investigate several different spatial elements both qualitatively and quantitatively using phantom measurements and data from human subjects. In addition, we also use optical flow estimation by the Horn-Schunk method as complementary data in regions where the velocity measurements are noisy. Our results show that it is possible to obtain good motion tracking accuracy in phantoms with relatively few spatial elements, if the type of element is properly chosen. The use of optical flow can correct some measurement artifacts but may give an underestimation of the magnitude of the deformation. In human subjects the different spatial elements perform quantitatively in a similar way but qualitative differences exists, as shown by a semiquantitative visual scoring of the different methods.
4.	Borgquist, Ola, et al. (författare) Measurements of wound edge microvascular blood flow during negative pressure wound therapy using thermodiffusion and transcutaneous and invasive laser Doppler velocimetry 2011 Ingår i: Wound Repair and Regeneration. - 1524-475X. ; 19:6, s. 727-733 Tidskriftsartikel (refereegranskat)abstract The effects of negative pressure wound therapy (NPWT) on wound edge microvascular blood flow are not clear. The aim of the present study was therefore to further elucidate the effects of NPWT on periwound blood flow in a porcine peripheral wound model using different blood flow measurement techniques. NPWT at -20, -40, -80, and -125 mmHg was applied to a peripheral porcine wound (n = 8). Thermodiffusion, transcutaneous, and invasive laser Doppler velocimetry were used to measure the blood perfusion 0.5, 1.0, and 2.5 cm from the wound edge. Thermodiffusion (an invasive measurement technique) generally showed a decrease in perfusion close to the wound edge (0.5 cm), and an increase further from the edge (2.5 cm). Invasive laser Doppler velocimetry showed a similar response pattern, with a decrease in blood flow 0.5 cm from the wound edge and an increase further away. However, 1.0 cm from the wound edge blood flow decreased with high pressure levels and increased with low pressure levels. A different response pattern was seen with transcutaneous laser Doppler velocimetry, showing an increase in blood flow regardless of the distance from the wound edge (0.5, 1.0, and 2.5 cm). During NPWT, both increases and decreases in blood flow can be seen in the periwound tissue depending on the distance from the wound edge and the pressure level. The pattern of response depends partly on the measurement technique used. The combination of hypoperfusion and hyperperfusion caused by NPWT may accelerate wound healing.
5.	Claesson, Erik, 1988- (författare) Carbides in martensitic medium carbon low alloyed tool steels studied with small angle scattering techniques, electron microscopy and atom probe tomography 2023 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Medium carbon low alloyed tool steels are used today in various areas to shape plastics, nonferrous metals, and steels, and they are crucial in the manufacturing industry. To be effective, tool steels must be strong and tough, and have high wear resistance and temperature stability. To achievethe desired properties, materials are alloyed so that secondary phaseparticles precipitate during processing, especially during the tempering of martensitic steels. However, the hardening contribution relates to the size,volume fraction and number density of precipitates, controlled by alloy composition and heat-treating parameters. It is therefore essential to understand how, where, and when the particles nucleate and how the precipitation sequence and kinetics are affected by alloying additions,tempering temperature, and time.This work is aimed to study carbide precipitation in two commercial low-alloy tool steel using small-angle neutron and X-ray scattering. To support these methods, samples were characterized with transmission electronmicroscopy (TEM) and atom probe tomography (APT). With a combination of high-resolution techniques, it was possible to establish the precipitation sequence in these steels. It was also possible with various small angle scattering techniques to determine the evolution of volume fraction and number density of precipitates as a function of tempering parameters.First, small angle neutron scattering (SANS) was used, which is an excellent method for bulk quantification of small precipitates in steel. It was possible with SANS to broadly study the precipitation process depending on annealing temperature and time. However, it is difficult with regular small angle scattering (SAS) to distinguish particle types with overlapping size distributions. To possibly separate the scattering signal from different carbide types, measurements were carried out with polarized small angle neutron scattering (SANSPOL) and anomalous small-angle X-ray scattering(ASAXS). With ASAXS it was possible to isolate the signal from molybdenum-rich carbides from other types of carbides.With SANSPOL, it was possible to follow the enrichment of alloy elements in cementite. The appearance of cementite can be described as an iron-richcore with a chromium-enriched shell. The partitioning of substitutional elements affects the stability of cementite and the alloy carbides. It was also possible with SANSPOL, during heating, to follow the initial precipitation of particles.Results from different experimental methods have been compared with precipitation simulations using thermodynamics-based precipitationmodeling. Equilibrium calculations indicates the possible stability ofdifferent precipitates, and the kinetics are captured with tools such as TCPRISMA to simulate structure evolution during tempering. Hardness measurements were made to correlate structure evolution to mechanical properties.
6.	Hedström, Erik, et al. (författare) Effects of gadolinium contrast agent on aortic blood flow and myocardial strain measurements by phase-contrast cardiovascular magnetic resonance 2010 Ingår i: Journal of Cardiovascular Magnetic Resonance. - 1097-6647. ; 12 Tidskriftsartikel (refereegranskat)abstract Background: Quantitative blood flow and aspects of regional myocardial function such as myocardial displacement and strain can be measured using phase-contrast cardiovascular magnetic resonance (PC-CMR). Since a gadolinium-based contrast agent is often used to measure myocardial infarct size, we sought to determine whether the contrast agent affects measurements of aortic flow and myocardial displacement and strain. Phase-contrast data pre and post contrast agent was acquired during free breathing using 1.5T PC-CMR. Results: For aortic flow and regional myocardial function 12 and 17 patients were analysed, respectively. The difference pre and post contrast agent was 0.03 +/- 0.16 l/min for cardiac output, and 0.1 +/- 0.5 mm for myocardial displacement. Linear regression for myocardial displacement (MD) after and before contrast agent (CA) showed MDpostCA = 0.95MD(preCA)+0.05 (r = 0.95, p < 0.001). For regional myocardial function, the contrast-to-noise ratios for left ventricular myocardial wall versus left ventricular lumen were pre and post contrast agent administration 7.4 +/- 3.3 and 4.4 +/- 8.9, respectively (p < 0.001). The contrast-to-noise ratios for left ventricular myocardial wall versus surrounding tissue were pre and post contrast agent administration -16.9 +/- 22 and -0.2 +/- 6.3, respectively (p < 0.0001). Conclusions: Quantitative measurements of aortic flow yield equal results both in the absence and presence of gadolinium contrast agent. The total examination time may thereby be reduced when assessing both viability and quantitative flow using PC-CMR, by assessing aortic flow post contrast agent administration. Phase-contrast information for myocardial displacement is also assessable both in the absence and presence of contrast agent. However, delineation of the myocardium may be difficult or impossible post contrast agent due to the lower image contrast. Acquisition of myocardial displacement should therefore be performed pre contrast agent using current PC-CMR sequences.
7.	Hedström, Erik, et al. (författare) Model based cardiac motion tracking using velocity encoded magnetic resonance imaging 2007 Ingår i: Image Analysis (Lecture Notes in Computer Science). - Berlin, Heidelberg : Springer Berlin Heidelberg. - 0302-9743 .- 1611-3349. - 9783540730392 ; 4522, s. 82-91 Konferensbidrag (refereegranskat)abstract This paper deals with model based regularization of velocity encoded cardiac magnetic resonance images (MRI). We extend upon an existing spatiotemporal model of cardiac kinematics by considering data certainty and regularity of the model in order to improve its performance. The method was evaluated using a computer simulated phantom and using in vivo gridtag MRI as gold standard. We show, both quantitatively and qualitatively, that our modified model performs better than the original one.
8.	Stenberg, Erik, 1979-, et al. (författare) Bariatric and metabolic surgery in patients with morbid obesity and multiple sclerosis : a nationwide, matched cohort study 2021 Ingår i: Surgery for Obesity and Related Diseases. - : Elsevier. - 1550-7289 .- 1878-7533. ; 17:6, s. 1108-1114 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: Despite an association between obesity and multiple sclerosis (MS), very little is known regarding the safety and efficacy outcomes for patients with MS and severe obesity undergoing metabolic surgery.OBJECTIVES: The aim of the present study was to evaluate early complications and efficacy outcomes of metabolic surgery in patients with severe obesity and MS.SETTING: Nationwide, Sweden.METHODS: In this, matched cohort study, 196 patients with an MS diagnosis in the Swedish MS register who were undergoing metabolic surgery (gastric bypass or sleeve gastrectomy) with a registration in the Scandinavian Obesity Surgery Registry (SOReg) were matched 1:10 with a control group without MS diagnosis from the SOReg. A 2-stage matching procedure was used (exact match by surgical method, followed by propensity Score matching, including age, sex, preoperative BMI, surgical center, surgical access, year of surgery, hypertension, diabetes, sleep apnea, and dyslipidemia).RESULTS: Weight loss at 2 years after surgery was similar for patients with MS and controls (total weight loss 31.6 ± 9.1 versus 31.8 ± 9.2, P = .735). No significant differences were seen in either the overall postoperative complication rate (7.9% versus 7.2%, P = .778), or serious postoperative complications (3.7% versus 2.8%, P = .430). All aspects of health-related quality of life (HRQoL) improved in both groups but less so for the physical aspects of HRQoL in patients with MS.CONCLUSION: Metabolic surgery is a safe and efficient treatment for severe obesity in patients with MS, and it leads to subsequent improvements in HRQoL. Further studies addressing the effects of metabolic surgery on MS-related symptoms are needed.
9.	Andersson, Håkan S., 1967-, et al. (författare) Discovery of peptide toxins in ribbon worms: challenging claims of tetrodotoxin production 2015 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
10.	Andersson, Håkan S., 1967-, et al. (författare) Discovery of peptide toxins in the world’s longest animal (The bootlace worm; Lineus longissimus): challenging claims of tetrodotoxin production. 2015 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
11.	Andersson, Håkan S., 1967-, et al. (författare) The toxicity of ribbon worms: alpha-nemertides or tetrodotoxin, or both? 2016 Ingår i: Planta Medica. - : Georg Thieme Verlag KG. - 0032-0943 .- 1439-0221. ; 82:Supplement 1 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract The marine ribbon worms (nemerteans) are predators which capture their prey by everting a proboscis carrying a mixture of toxins which brings on rapid paralysis [1]. Moreover, ribbon worms have a thick layer of epidermal mucus of similar constitution. Tetrodotoxin (TTX) has been identified as one of these toxins [2]. The extreme toxicity of TTX (lethal by ingestion of 0.5-2 mg) is due to its ability to block voltage-gated sodium channels. Although several bacterial species (among these Vibrio sp.) have been linked to its synthesis, the biogenic origin and biosynthesis is unclear. One hypothesis is that TTX production occurs in a symbiotic relationship with its host, in this case the ribbon worm [3]. We have made significant effort to identify TTX in a setup for production through the cultivation of Vibrio alginolyticus in nutrient broth infused with mucus from the ribbon worm Lineus longissimus. Toxicity was demonstrated by fraction injections into shore crabs, but no TTX was found, and it could be shown conclusively that toxicity was unrelated to TTX and the Vibrio culture itself, and rather a constituent of the ribbon worm mucus [4]. The following studies led us to the discovery of a new class of peptides, the alpha-nemertides, in the mucus of the ribbon worms, which could be directly linked to the toxic effects. A literature review of the available evidence for TTX in ribbon worms show that the evidence in most cases are indirect, although notable exceptions exist. This points to the necessity to further investigate the presence and roles of TTX and alpha-nemertides in ribbon worms.
12.	Asgeirsson, Daniel, et al. (författare) Longitudinal shortening remains the principal component of left ventricular pumping in patients with chronic myocardial infarction even when the absolute atrioventricular plane displacement is decreased 2017 Ingår i: BMC Cardiovascular Disorders. - : Springer Science and Business Media LLC. - 1471-2261. ; 17:1 Tidskriftsartikel (refereegranskat)abstract Background: The majority (60%) of left ventricular (LV) stroke volume (SV) is generated by longitudinal shortening causing apical atrioventricular plane displacement (AVPD) in systole. The remaining SV is caused by radial inward motion of the epicardium both in the septal and the lateral wall. We aimed to determine if these longitudinal, septal and lateral contributions to LVSV are changed in patients with chronic myocardial infarction (MI). Methods: Patients with a chronic (>3 months) ST-elevation MI in the left anterior descending (LAD, n = 20) or right coronary artery (RCA, n = 16) and healthy controls (n = 20) were examined with cardiovascular magnetic resonance (CMR). AVPD was quantified in long axis cine CMR images and LV volumes and dimensions in short axis cine images. Results: AVPD was decreased both in patients with LAD-MI (11 ± 1 mm, p < 0.001) and RCA-MI (13 ± 1 mm, p < 0.05) compared to controls (15 ± 0 mm). However, the longitudinal contribution to SV was unchanged for both LAD-MI (58 ± 3%, p = 0.08) and RCA-MI (59 ± 3%, p = 0.09) compared to controls (64 ± 2%). The preserved longitudinal contribution despite decreased absolute AVPD was a results of increased epicardial dimensions (p < 0.01 for LAD-MI and p = 0.06 for RCA-MI). In LAD-MI the septal contribution to LVSV was decreased (5 ± 1%) compared to both controls (10 ± 1%, p < 0.01) and patients with RCA-MIs (10 ± 1%, p < 0.01). The lateral contribution was increased in LAD-MI patients (44 ± 3%) compared to both RCA-MI (35 ± 2%, p < 0.05) and controls (29 ± 2%, p < 0.001). Conclusion: Longitudinal shortening remains the principal component of left ventricular pumping in patients with chronic MI even when the absolute AVPD is decreased.
13.	Bacharova, Ljuba, et al. (författare) The Dipolar ElectroCARdioTOpographic (DECARTO)-like method for graphic presentation of location and extent of area at risk estimated from ST-segment deviations in patients with acute myocardial infarction 2009 Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 42:2, s. 172-180 Tidskriftsartikel (refereegranskat)abstract A graphic method was developed for presentation of the location and extent of the myocardium at risk in patients with acute myocardial infarction (AMI). This method is based on a mathematical processing of ST-segment deviations of standard 12-lead electrocardiogram following the concept of Titomir and Ruttkay-Nedecky in their dipolar electrocardiotopographic method. The center of the location of the area at risk is given by the spatial orientation of the resultant spatial ST vector, and the extent of the area at risk is derived from the Aldrich score. The areas at risk are projected on a spherical image surface, on which a texture of the anatomical quadrants of the ventricular surface and its coronary artery supply are projected. The method was tested in 10 patients with AMI with single-vessel disease, including 6 patients with an occlusion in the proximal left anterior descending coronary artery (LAD), 3 patients with an occlusion in the right coronary artery, and one patient with occlusion in the left circumflex coronary artery. The estimated areas at risk were compared with myocardial perfusion single photon emission computed tomography. Eight (80%) patients of 10 were correctly localized according to the Aldrich decision rules for the location of AMI. The areas at risk in patients with LAD occlusion correctly localized by the Aldrich score were situated in the anteroseptal and anterosuperior quadrants. In the inferior AMI group, the area at risk was localized in the posterolateral and inferior quadrants. The visual comparison with myocardial perfusion single photon emission computed tomography (SPECT) showed best agreement in patients with LAD involvement. The initial testing showed that this method allows a graphic presentation of estimated area at risk using clinically defined diagnostic rules. The area at risk can be displayed in images that are familiar for clinicians and can be compared with or superimposed on results of other imaging methods used in cardiology. (C) 2009 Elsevier Inc. All rights reserved.
14.	Berggren, Klas, et al. (författare) Super-Resolution Cine Image Enhancement for Fetal Cardiac Magnetic Resonance Imaging 2022 Ingår i: Journal of Magnetic Resonance Imaging. - : Wiley. - 1522-2586 .- 1053-1807. ; 56:1, s. 223-231 Tidskriftsartikel (refereegranskat)abstract BackgroundFetal cardiac magnetic resonance imaging (MRI) improves the diagnosis of congenital heart defects, but is sensitive to fetal motion due to long image acquisition time. This may be overcome with faster image acquisition with low resolution, followed by image enhancement to provide clinically useful images.PurposeTo combine phase-encoding undersampling with super-resolution neural networks to achieve high-resolution fetal cine cardiac MR images with short acquisition time.Study TypeProspective.SubjectsTwenty-eight fetuses (gestational week 36 [interquartile range 33–38 weeks]).Field Strength/Sequence1.5 T, balanced steady-state free precession (bSSFP) cine sequence.AssessmentImages were acquired using fully sampled Doppler ultrasound-gated clinical bSSFP cine as reference, with equivalent cine sequences with decreased phase-encoding resolution (25%, 33%, and 50% of clinical standard). Two super-resolution methods based on convolutional neural networks were proposed and evaluated (phasrGAN and phasrresnet). Data were partitioned into training (36 cine slices), validation (3 cine slices), and test sets (67 cine slices) without overlap. Conventional reconstruction methods using bicubic interpolation and k-space zeropadding were used for comparison. Three blinded observers scored image quality between 1 and 10.Statistical TestsImage scores are reported as median [interquartile range] and were compared using Mann–Whitney's nonparametric test with P < 0.05 showing statistically significant differences.ResultsBoth proposed methods showed no significant difference in image quality compared to clinical images (8 [7–8.5]) down to 33% (phasrGAN 8 [6.5–8]; phasrresnet 8 [7–8], all P ≥ 0.19) phase-encoding resolution, i.e., up to three times faster image acquisition, whereas bicubic interpolation and k-space zeropadding showed significantly lower quality for 33% phase-encoding resolution (both 7 [6–8]).Data ConclusionSuper-resolution enhancement can be used for fetal cine cardiac MRI to reduce image acquisition time while maintaining image quality. This may lead to an improved success rate for fetal cine MR imaging, as the impact of fetal motion is lessened by shortened acquisitions.Level of Evidence1Technical EfficacyStage 2
15.	Bhat, Misha, et al. (författare) Fetal iGRASP cine CMR assisting in prenatal diagnosis of complicated cardiac malformation with impact on delivery planning 2019 Ingår i: Clinical Physiology and Functional Imaging. - : Wiley. - 1475-0961 .- 1475-097X. ; 39:4, s. 231-235 Tidskriftsartikel (refereegranskat)abstract Limited visualisation of the fetal heart and vessels by fetal ultrasound due to suboptimal fetal position, patient habitus and skeletal calcification may lead to missed diagnosis, overdiagnosis and parental uncertainty. Counseling and delivery planning may in those cases also be tentative. The recent fetal cardiac magnetic resonance (CMR) reconstruction method utilising tiny golden angle iGRASP (iterative Golden-angle RAdial Sparse Parallel MRI) allows for cine imaging of the fetal heart for use in clinical practice. This case describes an unbalanced common atrioventricular canal where limited ultrasound image quality and visibility of the aortic arch precluded confirming or ruling out presence of a ventricular septal defect. Need of prostaglandins or neonatal intervention was thus uncertain. Cardiovascular magnetic resonance imaging confirmed ultrasound findings and added value by ruling out a significant ventricular septal defect and diagnosing arch hypoplasia. This confirmed the need of patient relocation for delivery at a paediatric cardiothoracic surgery centre and prostaglandins could be initiated before the standard postnatal ultrasound. The applied CMR method can thus improve diagnosis of complicated fetal cardiac malformation and has direct clinical impact. This article is protected by copyright. All rights reserved.
16.	Bidhult, Sebastian, et al. (författare) A new vessel segmentation algorithm for robust blood flow quantification from two-dimensional phase-contrast magnetic resonance images 2019 Ingår i: Clinical Physiology and Functional Imaging. - : Wiley. - 1475-0961 .- 1475-097X. ; 39:5, s. 327-338 Tidskriftsartikel (refereegranskat)abstract Blood flow measurements in the ascending aorta and pulmonary artery from phase-contrast magnetic resonance images require accurate time-resolved vessel segmentation over the cardiac cycle. Current semi-automatic segmentation methods often involve time consuming manual correction, relying on user experience for accurate results. The purpose of this study was to develop a semi-automatic vessel segmentation algorithm with shape constraints based on manual vessel delineations for robust segmentation of the ascending aorta and pulmonary artery, to evaluate the proposed method in healthy volunteers and patients with heart failure and congenital heart disease, to validate the method in a pulsatile flow phantom experiment, and to make the method freely available for research purposes. Algorithm shape constraints were extracted from manual reference delineations of the ascending aorta (n=20) and pulmonary artery (n=20) and were included into a semi-automatic segmentation method only requiring manual delineation in one image. Bias and variability (bias±SD) for flow volume of the proposed algorithm versus manual reference delineations were 0·0±1·9ml in the ascending aorta (n=151; 7 healthy volunteers; 144 heart failure patients) and -1·7±2·9 ml in the pulmonary artery (n=40; 25 healthy volunteers; 15 patients with atrial septal defect). Inter-observer bias and variability were lower (p=0·008) for the proposed semi-automatic method (-0·1±0·9ml) compared to manual reference delineations (1·5±5·1ml). Phantom validation showed good agreement between the proposed method and timer-and-beaker flow volumes (0·4±2·7ml). In conclusion, the proposed semi-automatic vessel segmentation algorithm can be used for efficient analysis of flow and shunt volumes in the aorta and pulmonary artery. This article is protected by copyright. All rights reserved.
17.	Bidhult, Sebastian, et al. (författare) Independent validation of metric optimized gating for fetal cardiovascular phase-contrast flow imaging 2019 Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 1522-2594 .- 0740-3194. ; 81:1, s. 495-503 Tidskriftsartikel (refereegranskat)abstract PURPOSE: To validate metric optimized gating phase-contrast MR (MOG PC-MR) flow measurements for a range of fetal flow velocities in phantom experiments. 2) To investigate intra- and interobserver variability for fetal flow measurements at an imaging center other than the original site.METHODS: MOG PC-MR was compared to timer/beaker measurements in a pulsatile flow phantom using a heart rate (∼145 bpm), nozzle diameter (∼6 mm), and flow range (∼130-700 mL/min) similar to fetal imaging. Fifteen healthy fetuses were included for intra- and interobserver variability in the fetal descending aorta and umbilical vein.RESULTS: Phantom MOG PC-MR flow bias and variability was 2% ± 23%. Accuracy of MOG PC-MR was degraded for flow profiles with low velocity-to-noise ratio. Intra- and interobserver coefficients of variation were 6% and 19%, respectively, for fetal descending aorta; and 10% and 17%, respectively, for the umbilical vein.CONCLUSION: Phantom validation showed good agreement between MOG and conventionally gated PC-MR, except for cases with low velocity-to-noise ratio, which resulted in MOG misgating and underestimated peak velocities and warranted optimization of sequence parameters to individual fetal vessels. Inter- and intraobserver variability for fetal MOG PC-MR imaging were comparable to previously reported values.
18.	Bidhult, Sebastian L, et al. (författare) A new validated T2* analysis method with certainty estimates for cardiac and liver iron load determination 2015 Ingår i: Journal of Cardiovascular Magnetic Resonance. - 1097-6647. ; 17:Suppl 1, s. 52-52 Tidskriftsartikel (refereegranskat)abstract Journal of Cardiovascular Magnetic Resonance 2015, 17:P52. doi:10.1186/1532-429X-17-S1-P52
19.	Bidhult, Sebastian, et al. (författare) Validation of a new T2* algorithm and its uncertainty value for cardiac and liver iron load determination from MRI magnitude images. 2015 Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 1522-2594 .- 0740-3194. ; 75:4, s. 1717-1729 Tidskriftsartikel (refereegranskat)abstract To validate an automatic algorithm for offline T2* measurements, providing robust, vendor-independent T2*, and uncertainty estimates for iron load quantification in the heart and liver using clinically available imaging sequences.
20.	Bidhult, Sebastian, et al. (författare) Validation of T1 and T2 algorithms for quantitative MRI : Performance by a vendor-independent software 2016 Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 16:1 Tidskriftsartikel (refereegranskat)abstract Background: Determination of the relaxation time constants T1 and T2 with quantitative magnetic resonance imaging is increasingly used for both research and clinical practice. Recently, groups have been formed within the Society of Cardiovascular Magnetic Resonance to address issues with relaxometry. However, so far they have avoided specific recommendations on methodology due to lack of consensus and current evolving research. Standardised widely available software may simplify this process. The purpose of the current study was to develop and validate vendor-independent T1 and T2 mapping modules and implement those in the versatile and widespread software Segment, freely available for research and FDA approved for clinical applications. Results: The T1 and T2 mapping modules were developed and validated in phantoms at 1.5T and 3T with reference standard values calculated from reference pulse sequences using the Nelder-Mead Simplex optimisation method. The proposed modules support current commonly available MRI pulse sequences and both 2- and 3-parameter curve fitting. Images acquired in patients using three major vendors showed vendor-independence. Bias and variability showed high agreement with T1 and T2 reference standards for T1 (range 214-1752ms) and T2 (range 45-338ms), respectively. Conclusions: The developed and validated T1 and T2 mapping and quantification modules generated relaxation maps from current commonly used MRI sequences and multiple signal models. Patient applications showed usability for three major vendors.
21.	Cain, Peter A, et al. (författare) Age and gender specific normal values of left ventricular mass, volume and function for gradient echo magnetic resonance imaging: a cross sectional study. 2009 Ingår i: BMC medical imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 9:2 Tidskriftsartikel (refereegranskat)abstract Knowledge about age-specific normal values for left ventricular mass (LVM), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) by cardiac magnetic resonance imaging (CMR) is of importance to differentiate between health and disease and to assess the severity of disease. The aims of the study were to determine age and gender specific normal reference values and to explore the normal physiological variation of these parameters from adolescence to late adulthood, in a cross sectional study.
22.	Cain, Peter, et al. (författare) Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects 2005 Ingår i: Clin Physiol Funct Imaging. - 1475-0961. ; 25:6, s. 332-9 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics. METHODS: A total of 102 healthy volunteers (12-81 years, 53 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults > or = 20 years). The influence of haemodynamic factors, exercise, and demographic factors on LVM were determined with multivariate linear regression. Results: LVM rose during adolescence and declined in adulthood. LVM and LVMBSA were higher in males both in adults (LVM: 188 +/- 22 g versus 139 +/- 21 g, P < 0.001; LVMBSA: 94 +/- 11 g m(-2) versus 80 +/- 11 g m(-2), P < 0.001) and in adolescents when adjusted for BSA (LVM: 128 +/- 29 g versus 107 +/- 20 g, P = 0.063; LVMBSA: 82 +/- 8 g m(-2) versus 71 +/- 10 g m(-2), P = 0.025). In adults, systolic blood pressure (SBP) and self-reported physical activity increased while meridional and circumferential wall stress were constant with age. Multivariate regression analysis revealed age, gender, and BSA as the major determinants of LVM (global R2 = 0.69). CONCLUSIONS: Normal LVM shows variation over a broad age range in both genders with a rise in adolescence and subsequent decline with increasing age in adulthood despite an increase in SBP and physical activity. BSA, age, and gender were found to be major contributors to the variation in LVM in healthy adults, while haemodynamic factors, exercise, and wall stress were not.
23.	Cain, Peter, et al. (författare) Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects 2007 Ingår i: Clinical Physiology and Functional Imaging. - 1475-0961. ; 27:4, s. 255-262 Tidskriftsartikel (refereegranskat)
24.	Carlsson, Minna B, et al. (författare) Left ventricular mass by 12-lead electrocardiogram in healthy subjects: comparison to cardiac magnetic resonance imaging. 2006 Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 39:1, s. 67-72 Tidskriftsartikel (refereegranskat)
25.	Carlsson, Marcus, et al. (författare) Myocardium at risk after acute infarction in humans on cardiac magnetic resonance: quantitative assessment during follow-up and validation with single-photon emission computed tomography. 2009 Ingår i: JACC: Cardiovascular Imaging. - : Elsevier BV. - 1876-7591 .- 1936-878X. ; 2:5, s. 569-576 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: Our goal was to validate myocardium at risk on T2-weighted short tau inversion recovery (T2-STIR) cardiac magnetic resonance (CMR) over time, compared with that seen with perfusion single-photon emission computed tomography (SPECT) in patients with ST-segment elevation myocardial infarction, and to assess the amount of salvaged myocardium after 1 week. BACKGROUND: To assess reperfusion therapy, it is necessary to determine how much myocardium is salvaged by measuring the final infarct size in relation to the initial myocardium at risk of the left ventricle (LV). METHODS: Sixteen patients with first-time ST-segment elevation myocardial infarction received (99m)Tc tetrofosmin before primary percutaneous coronary intervention. SPECT was performed within 4 h and T2-STIR CMR within 1 day, 1 week, 6 weeks, and 6 months. At 1 week, patients were injected with a gadolinium-based contrast agent for quantification of infarct size. RESULTS: Myocardium at risk at occlusion on SPECT was 33 +/- 10% of the LV. Myocardium at risk on T2-STIR did not differ from SPECT, at day 1 (29 +/- 7%, p = 0.49) or week 1 (31 +/- 6%, p = 0.16) but declined at week 6 (10 +/- 12%, p = 0.0096 vs. 1 week) and month 6 (4 +/- 11%, p = 0.0013 vs. 1 week). There was a correlation between myocardium at risk demonstrated by T2-STIR at week 1 and myocardium at risk by SPECT (r(2) = 0.70, p < 0.001), and the difference between the methods on Bland-Altman analysis was not significant (-2.3 +/- 5.7%, p = 0.16). Both modalities identified myocardium at risk in the same perfusion territory and in concordance with angiography. Final infarct size was 8 +/- 7%, and salvage was 75 +/- 19% of myocardium at risk. CONCLUSIONS: This study demonstrates that T2-STIR performed up to 1 week after reperfusion can accurately determine myocardium at risk as it was before opening of the occluded artery. CMR can also quantify salvaged myocardium as myocardium at risk minus final infarct size.
26.	Claesson, Erik, et al. (författare) Carbide Precipitation during Processing of Two Low-Alloyed Martensitic Tool Steels with 0.11 and 0.17 V/Mo Ratios Studied by Neutron Scattering, Electron Microscopy and Atom Probe 2022 Ingår i: Metals. - Basel, Switzerland : MDPI AG. - 2075-4701. ; 12:5 Tidskriftsartikel (refereegranskat)abstract Two industrially processed low-alloyed martensitic tool steel alloys with compositions Fe-0.3C-1.1Si-0.81Mn-1.5Cr-1.4Ni-1.1Mo-0.13V and Fe-0.3C-1.1Si-0.81Mn-1.4Cr-0.7Ni-0.8Mo-0.14V (wt.%) were characterized using small-angle neutron scattering (SANS), scanning electron microscopy (SEM), Scanning transmission electron microscopy (STEM), and atom probe tomography (APT). The combination of methods enables an understanding of the complex precipitation sequences that occur in these materials during the processing. Nb-rich primary carbides form at hot working, while Fe-rich auto-tempering carbides precipitate upon quenching, and cementite carbides grow during tempering when Mo-rich secondary carbides also nucleate and grow. The number density of Mo-rich carbides increases with tempering time, and after 24 h, it is two to three orders of magnitude higher than the Fe-rich carbides. A high number density of Mo-rich carbides is important to strengthen these low-alloyed tool steels through precipitation hardening. The results indicate that the Mo-rich secondary carbide precipitates are initially of MC character, whilst later they start to appear as M2C. This change of the secondary carbides is diffusion driven and is therefore mainly seen for longer tempering times at the higher tempering temperature of 600◦C.
27.	Claesson, Erik, et al. (författare) Early precipitation behavior of secondary carbides in medium carbon low alloyed tool steel studied by in-situ polarized small-angle scattering and precipitation modelling Tidskriftsartikel (refereegranskat)abstract The strength of tempered martensite in low alloyed tool steel depends on the precipitation of secondary carbides. Tempering parameters such as time and temperature together with heating rate to tempering temperature will influence the precipitation sequence and these critical process parameters must be controlled to achieve ultimate precipitation strengthening. In this work precipitation was studied in a low alloyed tool steel using in-situ polarized small angle scattering (SANSPOL) during heating and isothermal holding. It was possible with SANSPOL to study the initial precipitation of secondary Mo- and V-rich carbides. It was found that Mo- and V-rich carbides form above 500 °C, simultaneously to the formation of cementite, which started to form already at lower temperature. It was furthermore found that the cementite particles can be described as having a core-shell structure, the Mo-V-rich carbides small and were approximated as spherical. Precipitation simulations performed using TC-PRSIMA were finally performed to compare with the experimental results, and the simulations were found to describe the experimental results well.
28.	Claesson, Erik, et al. (författare) Evolution of iron carbides during tempering of low-alloy tool steel studied with polarized small angle neutron scattering, electron microscopy and atom probe 2022 Ingår i: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 194, s. 112464-112464 Tidskriftsartikel (refereegranskat)abstract The magnetic scattering of iron carbides in low-alloy tool steel was investigated ex-situ by polarized small angle neutron scattering measurements after tempering the steel at 550 °C and 600 °C. Magnetic features could be detected in the as-quenched sample resulting in a negative interference term, believed to be either θ-Fe3C, η-Fe2C, or ε-Fe2-3C. During tempering the evolution of cementite could be studied by the variation of the interference term and in γ-ratio, which is the ratio of the magnetic to nuclear scattering length density contrast. From scanning transmission electron microscopy (STEM) and atom probe tomography, it is evident that cementite (θ-Fe3C) is present directly when reaching the tempering temperature of either 550 °C or 600 °C. At longer tempering times, cementite gets enriched with substitutional elements like chromium and manganese, forming an enriched shell on the cementite particles. STEM and energy dispersive x-ray spectrometry show that the chemical composition of small cementite particles approaches that of Cr-rich M7C3 carbides after 24 h at 600 °C. It is also seen that small non-magnetic particles precipitate during tempering and these correspond well with molybdenum and vanadium-rich carbides.
29.	Claesson, Erik, et al. (författare) Mapping of the carbide precipitation sequence and the in-situ transformation of cementite in medium carbon low alloyed tool steel with Scanning Precession Electron Diffraction Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Precipitation of carbides after tempering at 600 °C of a medium carbon low alloyed tool steel was studied with scanning precession electron diffraction (SPED). The precipitation sequence was evaluated by mapping the carbide distribution on carbon extraction replicas. This gave detailed information about formed precipitates which could be identified based on electron diffraction. The experimental work was compared to equilibrium calculations and energy dispersive x-ray spectroscopy (EDX). It was found that precipitates ε-Fe2C within laths during quenching via auto-tempering. During reheating to tempering temperature ε-Fe2C was dissolved and replaced by cementite, θ-M3C, which predominately form on martensitic lath boundaries. Vanadium and molybdenum are known from literature to form cubic MC or hexagonal M2C carbides, respectively. In this work it was found that the small carbides in the early stage of tempering have predominantly a cubic MC structure, even if the V/Mo-ratio the studied steel was only 0.12. Later during tempering more stable carbides, such as M7C3 and M23C6, also form, and it was concluded that the M7C3 form both by separate nucleation and in-situ transformation on cementite. The latter phenomenon was seen as particles with a core of cementite and shell of M7C3 after 24 h at 600 °C of tempering.
30.	Claesson, Erik, et al. (författare) Scanning precession electron diffraction study of carbide precipitation sequence in low alloy martensitic Cr-Mo-V tool steel 2023 Ingår i: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 202 Tidskriftsartikel (refereegranskat)abstract Precipitation of carbides after tempering of a medium carbon low alloyed Cr-Mo-V tool steel at 600 degrees C was studied with scanning precession electron diffraction (SPED) in a transmission electron microscope (TEM). The precipitation sequence was evaluated by mapping the carbide distribution on carbon extraction replicas prepared from samples tempered for different durations of up to 24 h. The SPED results were supplemented by equilibrium calculations and energy dispersive x-ray spectroscopy (EDX) measurements in a TEM. It was found that e-Fe2C precipitates within martensite laths during quenching via auto-tempering. During reheating to tempering temperature e-Fe2C was dissolved and replaced by cementite, 0-M3C, which predominately form on martensite boundaries. It was further found that the small carbides in the early stage of tempering have predominantly a cubic MC structure, even if the V/Mo-ratio of the studied steel was only 0.12, and it is known from literature that V and Mo form cubic MC or hexagonal M2C carbides, respectively. Later during tempering more stable carbides, such as M7C3 and M23C6, also form, and it was concluded that the M7C3 form both by separate nucleation and precipitation on the cementite/matrix interface. The latter phenomenon was seen as particles with a core of cementite and a shell of M7C3 after 24 h of tempering.
31.	Claesson, Erik, et al. (författare) Selective characterization of Mo-rich secondary carbides in medium carbon low alloyed tool steel by anomalous small angle x-ray scattering Tidskriftsartikel (refereegranskat)abstract Anomalous small angle X-ray scattering was used to study Mo (Mo) rich secondary carbides during tempering of medium carbon low alloyed tool steel. The scattering contrast of Mo-rich carbides varies systematically close to the absorption edge of Mo. No anomalous effect could be seen for the as-quenched sample. However, a clear effect could be seen for all tempered conditions. By studying the energy dependency of scattering invariant, Mo-rich carbides are believed to have a MC structure in the early stages of tempering. The -ratio is decreasing with time which is believed to be related to the formation M2C carbides. This is more pronounced for samples tempered at 600 °C as compared to 550 °C. The volume fraction was calculated using the ASAXS gradient method. At 550 °C the volume fraction of (Mo,V)C was increasing up to 24 h of tempering to 1.7·10-3. At 600 °C tempering a maximum in volume fraction was reached already after 1 h with 1.6·10-3 fraction. The size and number density of carbides are more stable at 550 °C compared to 600 °C.
32.	Dorniak, Karolina, et al. (författare) Required temporal resolution for accurate thoracic aortic pulse wave velocity measurements by phase-contrast magnetic resonance imaging and comparison with clinical standard applanation tonometry : Cardiovascular Spring Meeting 2016 Ingår i: BMC Cardiovascular Disorders. - : Springer Science and Business Media LLC. - 1471-2261. ; 16:1, s. 1-9 Tidskriftsartikel (refereegranskat)abstract Background: Pulse wave velocity (PWV) is a biomarker for arterial stiffness, clinically assessed by applanation tonometry (AT). Increased use of phase-contrast cardiac magnetic resonance (CMR) imaging allows for PWV assessment with minor routine protocol additions. The aims were to investigate the acquired temporal resolution needed for accurate and precise measurements of CMR-PWV, and develop a tool for CMR-PWV measurements. Methods: Computer phantoms were generated for PWV = 2–20 m/s based on human CMR-PWV data. The PWV measurements were performed in 13 healthy young subjects and 13 patients at risk for cardiovascular disease. The CMR-PWV was measured by through-plane phase-contrast CMR in the ascending aorta and at the diaphragm level. Centre-line aortic distance was determined between flow planes. The AT-PWV was assessed within 2 h after CMR. Three observers (CMR experience: 15, 4, and <1 year) determined CMR-PWV. The developed tool was based on the flow-curve foot transit time for PWV quantification. Results: Computer phantoms showed bias 0.27 ± 0.32 m/s for a temporal resolution of at least 30 ms. Intraobserver variability for CMR-PWV were: 0 ± 0.03 m/s (15 years), -0.04 ± 0.33 m/s (4 years), and -0.02 ± 0.30 m/s (<1 year). Interobserver variability for CMR-PWV was below 0.02 ± 0.38 m/s. The AT-PWV overestimated CMR-PWV by 1.1 ± 0. 7 m/s in healthy young subjects and 1.6 ± 2.7 m/s in patients. Conclusions: An acquired temporal resolution of at least 30 ms should be used to obtain accurate and precise thoracic aortic phase-contrast CMR-PWV. A new freely available research tool was used to measure PWV in healthy young subjects and in patients, showing low intra- and interobserver variability also for less experienced CMR observers. Keywords: Aorta, Pulse wave velocity, Temporal resolution, Magnetic resonance imaging, Phase contrast, Applanation tonometry
33.	Engblom, Henrik, et al. (författare) Determination of the left ventricular long-axis orientation from a single short-axis MR image: relation to BMI and age. 2004 Ingår i: Clinical Physiology and Functional Imaging. - 1475-0961. ; 24:5, s. 310-315 Tidskriftsartikel (refereegranskat)
34.	Engblom, Henrik, et al. (författare) Rapid Initial Reduction of Hyperenhanced Myocardium After Reperfused First Myocardial Infarction Suggests Recovery of the Peri-Infarction Zone One-Year Follow-Up by MRI 2009 Ingår i: Circulation Cardiovascular Imaging. - 1942-0080. ; 2:1, s. 47-55 Tidskriftsartikel (refereegranskat)abstract Background-The time course and magnitude of infarct involution, functional recovery, and normalization of infarct-related electrocardiographic (ECG) changes after acute myocardial infarction (MI) are not completely known in humans. We sought to explore these processes early after MI and during infarct-healing using cardiac MRI. Methods and Results-Twenty-two patients with reperfused first-time MI were examined by MRI and ECG at 1, 7, 42. 182, and 365 days after infarction. Global left ventricular function and regional wall thickening were assessed by cine MRI, and injured myocardium was depicted by delayed contrast-enhanced MRI. Infarct size by ECG was estimated by QRS scoring. The reduction of hyperenhanced myocardium occurred predominantly during the first week after infarction (64% of the 1-year reduction). Furthermore, during the first week the amount of nonhyperenhanced myocardium increased significantly (P<0.001,), although the left ventricular mass remained unchanged. Left ventricular ejection fraction increased gradually, whereas the greater the regional transmural extent of hyperenhancement at day 1, the later the recovery of regional wall thickening. Regional wall thickening decreased progressively with increasing initial transmural extent of hyperenhancement (P-trend<0.0001). The time course and magnitude of decrease in QRS score corresponded with the reduction of hyperenhanced myocardium. Conclusions-The early reduction of hyperenhanced myocardium May reflect recovery of hyperenhanced, reversibly injured myocardium), which must be considered when predicting functional recovery from delayed contrast-enhanced MRI findings early after infarction. Also, the time course and magnitude for reduction of hyperenhanced myocardium were associated with normalization of infarct-related ECG changes. (Circ Cardiovasc Imaging. 2009;2:47-55.)
35.	Engblom, Henrik, et al. (författare) Size and transmural extent of first-time reperfused myocardial infarction assessed by cardiac magnetic resonance can be estimated by 12-lead electrocardiogram. 2005 Ingår i: American Heart Journal. - : Elsevier BV. - 1097-6744 .- 0002-8703. ; 150:5, s. 920-920 Tidskriftsartikel (refereegranskat)
36.	Engblom, Henrik, et al. (författare) The endocardial extent of reperfused first-time myocardial infarction is more predictive of pathologic Q waves than is infarct transmurality: a magnetic resonance imaging study. 2007 Ingår i: Clinical Physiology and Functional Imaging. - 1475-0961. ; 27:2, s. 101-108 Tidskriftsartikel (refereegranskat)abstract Historically, Q-wave myocardial infarction (MI) has been equated with transmural MI. This association have, however, recently been rejected. The endocardial extent of MI is another potential determinant of pathological Q waves, since the first part of the QRS complex where the Q wave appears reflects depolarization of subendocardial myocardium. Therefore, the aim of the present study was to test the hypothesis that endocardial extent of MI is more predictive of pathological Q waves than is MI transmurality and to investigate the relationship between QRS scoring of the ECG and MI characteristics. Twenty-nine patients with reperfused first-time MI were prospectively enrolled. One week after admission, delayed contrast-enhanced magnetic resonance imaging (DE-MRI) was performed and 12-lead ECG was recorded. Size, transmurality and endocardial extent of MI were assessed by DE-MRI. Q waves were identified with Minnesota coding and electrocardiographic MI size was estimated by QRS scoring of the ECG. There was a significant difference between patients with and without Q waves with regard to MI size (P = 0.03) and endocardial extent of MI (P = 0.01), but not to mean and maximum MI transmurality (P = 0.09 and P = 0.14). Endocardial extent was the only independent predictor of pathological Q waves. Endocardial extent of MI was most strongly correlated to QRS score (r = 0.86, P < 0.001) of the MI variables tested. The endocardial extent of reperfused first-time acute MI is more predictive of pathological Q waves than is MI transmurality.
37.	Engblom, Henrik, et al. (författare) The evaluation of an electrocardiographic myocardial ischemia acuteness score to predict the amount of myocardial salvage achieved by early percutaneous coronary intervention Clinical validation with myocardial perfusion single photon emission computed tomography and cardiac magnetic resonance. 2011 Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 44, s. 525-532 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: The time from symptom onset to reperfusion in acute myocardial infarction (MI) has been shown to be a poor predictor of patient outcome. Acute electrocardiographic (ECG) changes, however, have been shown useful for estimated acuteness of myocardial ischemia using the Anderson-Wilkins ECG ischemia acuteness score (AW-acuteness score). The aim was to study whether acute ischemic ECG changes can predict the amount of salvageable myocardium in patients with acute ST-elevation MI. METHODS: Thirty-eight patients treated with primary percutaneous coronary intervention for first-time ST-elevation MI were retrospectively enrolled. Myocardium at risk (MaR) was determined by myocardial perfusion single photon emission computed tomography acutely or by T2-weighted cardiac magnetic resonance after 1 week, at the same time when final MI size was determined by late gadolinium enhancement. Myocardial salvage was calculated as (MaR - MI size)/MaR and compared with AW-acuteness score and time from symptom onset to primary percutaneous coronary intervention. RESULTS: The AW-acuteness score correlated significantly with salvageable myocardium for right coronary artery (RCA) occlusions (r = -0.57; P = .02) but not for left anterior descending artery (LAD) occlusions (r = -0.04; P = .88). Time from symptom onset did not correlate with the amount of salvageable myocardium (LAD, r = 0.04 and P = .87; RCA, r = -0.40 and P = .13). CONCLUSIONS: There is a moderate correlation between AW-acuteness score and salvageable myocardium in patients with acute RCA occlusion but not in patients with LAD occlusion.
38.	Erlandsson, Lena, et al. (författare) Alpha-1 microglobulin as a potential therapeutic candidate for treatment of hypertension and oxidative stress in the STOX1 preeclampsia mouse model 2019 Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1 Tidskriftsartikel (refereegranskat)abstract Preeclampsia is a human placental disorder affecting 2-8% of pregnancies worldwide annually, with hypertension and proteinuria appearing after 20 weeks of gestation. The underlying cause is believed to be incomplete trophoblast invasion of the maternal spiral arteries during placentation in the first trimester, resulting in oxidative and nitrative stress as well as maternal inflammation and organ alterations. In the Storkhead box 1 (STOX1) preeclampsia mouse model, pregnant females develop severe and early onset manifestations as seen in human preeclampsia e.g. gestational hypertension, proteinuria, and organ alterations. Here we aimed to evaluate the therapeutic potential of human recombinant alpha-1 microglobulin (rA1M) to alleviate the manifestations observed. Human rA1M significantly reduced the hypertension during gestation and significantly reduced the level of hypoxia and nitrative stress in the placenta. In addition, rA1M treatment reduced cellular damage in both placenta and kidneys, thereby protecting the tissue and improving their function. This study confirms that rA1M has the potential as a therapeutic drug in preeclampsia, and likely also in other pathological conditions associated with oxidative stress, by preserving normal organ function.
39.	Ferry, Tomas, et al. (författare) Epidemiology of acute knee injuries seen at the Emergency Department at Umeå University Hospital, Sweden, during 15 years 2014 Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer. - 0942-2056 .- 1433-7347. ; 22:5, s. 1149-1155 Tidskriftsartikel (refereegranskat)abstract PURPOSE: To describe the incidence and injury distribution of knee injuries in the general population of a European setting. METHODS: Retrospective study of all knee injuries registered at the Emergency Department at Umeå University Hospital, Sweden, during 1995-2009 in relation to age, sex, diagnosis, location and activity at the time of injury, mechanism of injury, and treatment and/or follow-up plan. RESULTS: During 1995-2009, 12,663 knee injuries were registered, 8 % of all injuries. The incidence of knee injuries resulting in a visit to the Emergency Department was six cases per 1,000 person years. One-third of all injuries occurred during sports. And 30 % were 15-24 years. More men than women were injured during sporting activities and women were mostly injured during transportation. CONCLUSION: Knee injuries in a general population are common and the injury distribution varies with age and sex. Sports activities and young age were prominent features of the injured population. LEVEL OF EVIDENCE: IV.
40.	Fransson, Helen, et al. (författare) An automatic method for quantification of myocardium at risk from myocardial perfusion SPECT in patients with acute coronary occlusion. 2010 Ingår i: Journal of Nuclear Cardiology. - : Springer Science and Business Media LLC. - 1532-6551 .- 1071-3581. ; 17, s. 831-840 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: In order to determine myocardial salvage, accurate quantification of myocardium at risk (MaR) is necessary. We present a validated novel automatic segmentation algorithm for quantification of MaR by myocardial perfusion SPECT (MPS) in patients with acute coronary occlusion. METHODS AND RESULTS: Twenty-nine patients with coronary occlusion were injected with a perfusion tracer before reperfusion, and underwent rest MPS within 4 hours. The MaR was quantified using the proposed algorithm (Segment software), the software Quantitative Perfusion SPECT (QPS) and by manual segmentation. The Segment MaR algorithm used a threshold of 55% of maximal counts and an a priori model based on normal coronary artery perfusion territories. The MaR was 30 +/- 10% left ventricular mass (%LVM) by manual segmentation, 31 +/- 12%LVM by Segment, and 36 +/- 14%LVM by QPS. There was a good agreement between automatic and manual segmentation for both of the algorithms with a lower bias for Segment (.8 +/- 4.0%LVM) than for QPS (5.8 +/- 5.8%LVM) when compared to manual segmentation. CONCLUSIONS: The Segment MaR algorithm can be used to correctly assess MaR from MPS images in patients with acute coronary occlusion without access to tracer-specific normal database. The MaR in relation to final infarct size enables determination of myocardial salvage.
41.	Freden, Sven, et al. (författare) Reserapport från Järnvägsavdelningens studieresa till Storbritannien 1992-11-02--05 1992 Rapport (övrigt vetenskapligt/konstnärligt)
42.	Fricke, Katrin, et al. (författare) Fetal cardiac magnetic resonance imaging of the descending aorta in suspected left-sided cardiac obstructions 2023 Ingår i: Frontiers in Cardiovascular Medicine. - 2297-055X. ; 10, s. 01-10 Tidskriftsartikel (refereegranskat)abstract Background: Severe left-sided cardiac obstructions are associated with high morbidity and mortality if not detected in time. The correct prenatal diagnosis of coarctation of the aorta (CoA) is difficult. Fetal cardiac magnetic resonance imaging (CMR) may improve the prenatal diagnosis of complex congenital heart defects. Flow measurements in the ascending aorta could aid in predicting postnatal CoA, but its accurate visualization is challenging.Objectives: To compare the flow in the descending aorta (DAo) and umbilical vein (UV) in fetuses with suspected left-sided cardiac obstructions with and without the need for postnatal intervention and healthy controls by fetal phase-contrast CMR flow. A second objective was to determine if adding fetal CMR to echocardiography (echo) improves the fetal CoA diagnosis.Methods: Prospective fetal CMR phase-contrast flow in the DAo and UV and echo studies were conducted between 2017 and 2022.Results: A total of 46 fetuses with suspected left-sided cardiac obstructions [11 hypoplastic left heart syndrome (HLHS), five critical aortic stenosis (cAS), and 30 CoA] and five controls were included. Neonatal interventions for left-sided cardiac obstructions (n = 23) or comfort care (n = 1 with HLHS) were pursued in all 16 fetuses with suspected HLHS or cAS and in eight (27%) fetuses with true CoA. DAo or UV flow was not different in fetuses with and without need of intervention. However, DAo and UV flows were lower in fetuses with either retrograde isthmic systolic flow [DAo flow 253 (72) vs. 261 (97) ml/kg/min, p = 0.035; UV flow 113 (75) vs. 161 (81) ml/kg/min, p = 0.04] or with suspected CoA and restrictive atrial septum [DAo flow 200 (71) vs. 268 (94) ml/kg/min, p = 0.04; UV flow 89 vs. 159 (76) ml/kg/min, p = 0.04] as well as in those without these changes. Adding fetal CMR to fetal echo predictors for postnatal CoA did not improve the diagnosis of CoA.Conclusion: Fetal CMR-derived DAo and UV flow measurements do not improve the prenatal diagnosis of left-sided cardiac obstructions, but they could be important in identifying fetuses with a more severe decrease in blood flow across the left side of the heart. The physiological explanation may be a markedly decreased left ventricular cardiac output with subsequent retrograde systolic isthmic flow and decreased total DAo flow.
43.	Frieberg, Petter, et al. (författare) In vivo hepatic flow distribution by computational fluid dynamics can predict pulmonary flow distribution in patients with Fontan circulation 2023 Ingår i: Scientific Reports. - 2045-2322. ; 13:1 Tidskriftsartikel (refereegranskat)abstract In Fontan patients, a lung deprived of hepatic blood may develop pulmonary arterio-venous malformations (PAVMs) resulting in shunting, reduced pulmonary vascular resistance (PVR) and decreased oxygenation. To provide guidance for corrective invasive interventions, we aimed to non-invasively determine how the hepatic to pulmonary blood flow balance correlates with pulmonary flow, PVR, and with oxygen saturation. Magnetic resonance imaging (MRI) data from eighteen Fontan patients (eight females, age 3–14 years) was used to construct patient-specific computational fluid dynamics (CFD) models to calculate the hepatic to pulmonary blood flow. This was correlated with pulmonary vein flow, simulated PVR and oxygen saturation. Clinical applicability of the findings was demonstrated with an interventional patient case. The hepatic to pulmonary blood flow balance correlated with right/left pulmonary vein flow (R2 = 0.50), left/right simulated PVR (R2 = 0.47), and oxygen saturation at rest (R2 = 0.56). In the interventional patient, CFD predictions agreed with post-interventional MRI measurements and with regressions in the cohort. The balance of hepatic blood to the lungs has a continuous effect on PVR and oxygen saturation, even without PAVM diagnosis. MRI combined with CFD may help in planning of surgical and interventional designs affecting the hepatic to pulmonary blood flow balance in Fontan patients.
44.	Glimskär, Anders, et al. (författare) Uppföljning av kvalitetsförändringar i ängs- och betesmark via NILS år 2008 2009 Rapport (övrigt vetenskapligt/konstnärligt)abstract Denna rapport presenterar resultat för ett antal indikatorer på kvalitet och skötsel i ett stickprov av ängs- och betesmarker i hela Sverige. Inventeringen och analyserna görs varje år från och med 2006 på uppdrag av Jordbruksverket, som underlag för bl.a. utvärderingen av miljökvalitetsmålet Ett rikt odlingslandskap. Som indikatorer har i första hand valts ett antal organismgrupper (fjärilar, humlor, kärlväxter, grova lövträd och epifytlavar), och dessutom beskrivs vegetationens struktur och sammansättning i provytor, som underlag för att ta fram strukturella indikatorer (t.ex. påverkan av gödsling och hävdintensitet/igenväxning). Urvalet bygger på förslag som tagits fram av Naturcentrum AB. De resultat som presenteras i denna rapport kommer från de första tre årens inventering, vilket innefattar tre femtedelar av det totala stickprovet. Efter fem år får man således de mest tillförlitliga mängdskattningarna. Därefter återkommer man till samma objekt med samma intervall, vilket gör att man på ett tillförlitligt sätt kan analysera förändringar baserat på jämförelser mellan femårsperioder. Uppdraget att inventera ängs- och betesmarker samordnas med fältarbetet i NILS (Nationell Inventering av Landskapet i Sverige), och metodiken är till stor del likartad, med en del tilläggsmoment. NILS är ett rikstäckande miljöövervakningsprogram som följer tillstånd och förändringar i det svenska landskapet och hur dessa påverkar förutsättningarna för den biologiska mångfalden. NILS finansieras av Naturvårdsverket och ingår i programområde Landskap. Ett viktigt syfte med NILS är att följa upp de nationella miljökvalitetsmålen för olika naturtyper och fungera som underlag för att till exempel visa om genomförda miljövårdsåtgärder leder till önskade förbättringar på nationell nivå eller landsdelsnivå. Arbetet har utförts vid institutionen för skoglig resurshushållning, Sveriges lantbruksuniversitet, Umeå, i samarbete med inst. för ekologi, SLU och avd. för biologi/IFM, Linköpings universitet. Erik Cronvall och Åsa Gallegos Torell (SLU, inst. för skoglig resurshushållning) har ansvarat för fältkurser och genomförandet av fältinventeringen tillsammans med säsongsanställd fältpersonal, med stöd av bl.a. Kjell Lagerqvist (SLU) och Karl-Olof Bergman (Linköpings universitet). Beräkningarna har utförts av Saskia Sandring och Åsa Eriksson, med stöd av Anna Ringvall (SLU). Sammanställandet av rapporten har utförts av Anders Glimskär och Jörgen Wissman (SLU). NILS programchef Johan Svensson (SLU) har det övergripande ansvaret för uppdraget
45.	Glimskär, Anders, et al. (författare) Uppföljning av kvalitetsändringar i ängs- och betesmark via NILS år 2008 2009 Rapport (övrigt vetenskapligt/konstnärligt)abstract Denna rapport presenterar resultat för ett antal indikatorer på kvalitet och skötsel i ett stickprov av ängs- och betesmarker i hela Sverige. Inventeringen och analyserna görs varje år från och med 2006 på uppdrag av Jordbruksverket, som underlag för bl.a. utvärderingen av miljökvalitetsmålet Ett rikt odlingslandskap. Som indikatorer har i första hand valts ett antal organismgrupper (fjärilar, humlor, kärlväxter, grova lövträd och epifytlavar), och dessutom beskrivs vegetationens struktur och sammansättning i provytor, som underlag för att ta fram strukturella indikatorer (t.ex. påverkan av gödsling och hävdintensitet/igenväxning). Urvalet bygger på förslag som tagits fram av Naturcentrum AB. De resultat som presenteras i denna rapport kommer från de första tre årens inventering, vilket innefattar tre femtedelar av det totala stickprovet. Efter fem år får man således de mest tillförlitliga mängdskattningarna. Därefter återkommer man till samma objekt med samma intervall, vilket gör att man på ett tillförlitligt sätt kan analysera förändringar baserat på jämförelser mellan femårsperioder. Uppdraget att inventera ängs- och betesmarker samordnas med fältarbetet i NILS (Nationell Inventering av Landskapet i Sverige), och metodiken är till stor del likartad, med en del tilläggsmoment. NILS är ett rikstäckande miljöövervakningsprogram som följer tillstånd och förändringar i det svenska landskapet och hur dessa påverkar förutsättningarna för den biologiska mångfalden. NILS finansieras av Naturvårdsverket och ingår i programområde Landskap. Ett viktigt syfte med NILS är att följa upp de nationella miljökvalitetsmålen för olika naturtyper och fungera som underlag för att till exempel visa om genomförda miljövårdsåtgärder leder till önskade förbättringar på nationell nivå eller landsdelsnivå.
46.	Granholm, Martina, 1969- (författare) Materialitetens roller och förutsättningar i kommunal krisledning 2019 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Arbetet med denna licentiatavhandling har skett inom ramarna för det Interregionalt finansierade projektet Gränslös samverkan för ökad säkerhet 2. Syftet med avhandlingen har varit att fördjupa kunskapen om kommunal krisledning genom att också inkludera materialitetens medverkan i krisledningen och vilka förutsättningarna är för att de ska brukas. Med perspektivet av hur analoga och digitala resurser används under krisledning och vilka förutsättningar som finns för att detta ska göras skapas insikter att ta i beaktande när övningar och IT-stöd för övningar. Studier har genomförts med en kvalitativ ansats med litteraturstudier, intervjuer och observationer som datainsamlingsmetoder. Det empiriska materialet har därefter betraktats med meningsgivande (sensemaking) och affordans (affordance) som teoretiska perspektiv för att förstå materialitetens roll och förutsättning i kommunal krisledning.Avhandlingen visar att de förmågor som är återkommande under övningar är samverkan, kommunikation, informationsdelning och skapande av lägesbild. Ofta övas inte aktiviteterna i sin helhet då tekniska och analoga resurser inte innefattas i övningarna. Aktörerna övar därmed delar av görandet, att tänka kring exempelvis att skapa en lägesbild, och inte görandet som helhet som involverar materialitet. Aktörernas egna reflektioner från utvärderingarna är att de själva önskar mer övning med de tekniska resurser som de har till sitt förfogande. Artikel II visar att materialiteten tar en stor plats i det arbete som sker i krisledningsrummet. Materialiteten kan ses anta roller som strukturgivande, meningsgivande, tidsöverbryggande och distansöverbryggande. Den tredje ingående artikeln visar att förutsättningar för att kunna bedriva krisledning är att kunna hantera materialitetens roller och att det krävs flexibilitet då krisledningsgruppens sammansättning är beroende av krisens art och omfattning. Ytterligare en förutsättning är trygghet i den egna organisationen, att känna sin egen roll i krisledningsgruppen och att kunna hantera de analoga och digitala resurser som finns tillgängliga är även det en förutsättning för arbetet. Avslutningsvis visar arbetet också att tid är viktig. Tid att kunna öva de personer som ska ingå i krisledningsgruppen för att därmed kunna skapa den trygghet som behövs.
47.	Haris, Kostas, et al. (författare) Fetal Cardiac Magnetic Resonance Imaging with self-gated iGRASP 2016 Konferensbidrag (refereegranskat)
48.	Haris, Kostas, et al. (författare) Free-breathing fetal cardiac MRI with doppler ultrasound gating, compressed sensing, and motion compensation 2020 Ingår i: Journal of Magnetic Resonance Imaging. - : Wiley. - 1522-2586 .- 1053-1807. ; 51:1, s. 260-272 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: Fetal cardiovascular MRI complements ultrasound to assess fetal cardiovascular pathophysiology.PURPOSE: To develop a free-breathing method for retrospective fetal cine MRI using Doppler ultrasound (DUS) cardiac gating and tiny golden angle radial sampling (tyGRASP) for accelerated acquisition capable of detecting fetal movements for motion compensation.STUDY TYPE: Feasibility study.SUBJECTS: Nine volunteers (gestational week 34-40). Short-axis and four-chamber views were acquired during maternal free-breathing and breath-hold.FIELD STRENGTH/SEQUENCE: 1.5T cine balanced steady-state free precession.ASSESSMENT: A self-gated reconstruction method was improved for clinical application by using 1) retrospective DUS gating, and 2) motion detection and rejection/correction algorithms for compensating for fetal motion. The free-breathing reconstructions were qualitatively and quantitatively assessed, and DUS-gating was compared with self-gating in breath-hold reconstructions. A scoring of 1-4 for overall image quality, cardiac, and extracardiac diagnostic quality was used.STATISTICAL TESTS: Friedman's test was used to assess differences in qualitative scoring between observers. A Wilcoxon matched-pairs signed rank test was used to assess differences between breath-hold and free-breathing acquisitions and between observers' quantitative measurements.RESULTS: In all cases, 111 free-breathing and 145 breath-hold acquisitions, the automatically calculated DUS-based cardiac gating signal provided reconstructions of diagnostic quality (median score 4, range 1-4). Free-breathing did not affect the DUS-based cardiac gated retrospective radial reconstruction with respect to image or diagnostic quality (all P > 0.06). Motion detection with rejection/correction in k-space produced high-quality free-breathing DUS-based reconstructions [median 3, range (2-4)], whereas free-breathing self-gated methods failed in 80 out of 88 cases to produce a stable gating signal.DATA CONCLUSION: Free-breathing fetal cine cardiac MRI based on DUS gating and tyGRASP with motion compensation yields diagnostic images. This simplifies acquisition for the pregnant woman and thus could help increase fetal cardiac MRI acceptance in the clinic.LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019.
49.	Haris, Kostas, et al. (författare) Self-gated fetal cardiac MRI with tiny golden angle iGRASP : A feasibility study 2017 Ingår i: Journal of Magnetic Resonance Imaging. - : Wiley. - 1522-2586 .- 1053-1807. ; 46:1, s. 207-217 Tidskriftsartikel (refereegranskat)abstract PURPOSE: To develop and assess a technique for self-gated fetal cardiac cine magnetic resonance imaging (MRI) using tiny golden angle radial sampling combined with iGRASP (iterative Golden-angle RAdial Sparse Parallel) for accelerated acquisition based on parallel imaging and compressed sensing.MATERIALS AND METHODS: Fetal cardiac data were acquired from five volunteers in gestational week 29-37 at 1.5T using tiny golden angles for eddy currents reduction. The acquired multicoil radial projections were input to a principal component analysis-based compression stage. The cardiac self-gating (CSG) signal for cardiac gating was extracted from the acquired radial projections and the iGRASP reconstruction procedure was applied. In all acquisitions, a total of 4000 radial spokes were acquired within a breath-hold of less than 15 seconds using a balanced steady-state free precession pulse sequence. The images were qualitatively compared by two independent observers (on a scale of 1-4) to a single midventricular cine image from metric optimized gating (MOG) and real-time acquisitions.RESULTS: For iGRASP and MOG images, good overall image quality (2.8 ± 0.4 and 2.6 ± 1.3, respectively, for observer 1; 3.6 ± 0.5 and 3.4 ± 0.9, respectively, for observer 2) and cardiac diagnostic quality (3.8 ± 0.4 and 3.4 ± 0.9, respectively, for observer 1; 3.6 ± 0.5 and 3.6 ± 0.9, respectively, for observer 2) were obtained, with visualized myocardial thickening over the cardiac cycle and well-defined myocardial borders to ventricular lumen and liver/lung tissue. For iGRASP, MOG, and real time, left ventricular lumen diameter (14.1 ± 2.2 mm, 14.2 ± 1.9 mm, 14.7 ± 1.1 mm, respectively) and wall thickness (2.7 ± 0.3 mm, 2.6 ± 0.3 mm, 3.0 ± 0.4, respectively) showed agreement and no statistically significant difference was found (all P > 0.05). Images with iGRASP tended to have higher overall image quality scores compared with MOG and particularly real-time images, albeit not statistically significant in this feasibility study (P > 0.99 and P = 0.12, respectively).CONCLUSION: Fetal cardiac cine MRI can be performed with iGRASP using tiny golden angles and CSG. Comparison with other fetal cardiac cine MRI methods showed that the proposed method produces high-quality fetal cardiac reconstructions.LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017.
50.	Havstorm, Tanja Elina, 1991- (författare) Cargo Cult in Agile Software Development 2023 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Software development (SD) projects are complex endeavors, and organizations employ software development methods (SDMs) both to add structure and to propel their projects. Nowadays, agile SDMs are the most used methods. Still, inefficient and ineffective use of SDMs is a challenge, and existing research shows cases of SD teams failing in their use of SDMs due to deviations made. Of course, methods should not be used in rigorous and textbook-like ways. Among practitioners, some of these deviations are referred to as cargo cult behavior; without, however, providing much of theoretical depth or any analytical tools to identify and characterize such behaviors. Although existing research has investigated SDM deviations, they have not been investigated as cargo cult behavior.Against this backdrop, the aim of this thesis is to understand the challenges in succeeding with SDM use by developing a theory called SDM cargo cult theory (SDMCCT), to identify, analyze, and describe the cargo cult phenomenon in agile SDM use. The journey of this thesis takes its starting point in practitioners’ use of the buzzwords “cargo cult” when referring to flawed SDM use. By returning to the field of social anthropology and its studies of cargo cult, a definition of SDM cargo cult and an analytical framework are iteratively crafted through a longitudinal ethnographic study to constitute the SDMCCT. The research approach has been abductive and the SDMCCT builds on social action theory and work motivation theory.The ethnographical study took place at an international industrial manufacturing company in Sweden that is using agile SDMs. This study includes three years of data collection, which includes observations, interviews, and gathering of business documents. The ethnographic study focused on three SD teams and their daily work using agile SDMs. The analysis using the analytical framework includes four agile SDM practices: daily scrum meeting, sprint demo, continuous integration, and visualization. In total, the analysis uncovered 36 deviations in the SD teams’ use of these practices, structured into 30 SDM cargo cult categories. In addition, this study shows that the framework is applicable to analyze and characterize effective SDM use as well, although it is not its main focus. The framework can be used by researchers to make similar analysis of cargo cult situations in other organizations, and the catalogue of cargo cult situations can serve as background knowledge for other organizations to study and improve their SD teams’ use of agile SDM practices.

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