| 1. |
- 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.
|
|
| 2. |
- Hedén, Bo, et al.
(författare)
-
Disappearance of myocardial perfusion defects on prone SPECT imaging : Comparison with cardiac magnetic resonance imaging in patients without established coronary artery disease
- 2009
-
Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Background: It is of great clinical importance to exclude myocardial infarction in patients with suspected coronary artery disease who do not have stress-induced ischemia. The diagnostic use of myocardial perfusion single-photon emission computed tomography (SPECT) in this situation is sometimes complicated by attenuation artifacts that mimic myocardial infarction. Imaging in the prone position has been suggested as a method to overcome this problem. Methods: In this study, 52 patients without known prior infarction and no stress-induced ischemia on SPECT imaging were examined in both supine and prone position. The results were compared with cardiac magnetic resonance imaging (CMR) with delayed-enhancement technique to confirm or exclude myocardial infarction. Results: There were 63 defects in supine-position images, 37 of which disappeared in the prone position. None of the 37 defects were associated with myocardial infarction by CMR, indicating that all of them represented attenuation artifacts. Of the remaining 26 defects that did not disappear on prone imaging, myocardial infarction was confirmed by CMR in 2; the remaining 24 had no sign of ischemic infarction but 2 had other kinds of myocardial injuries. In 3 patients, SPECT failed to detect small scars identified by CMR. Conclusion: Perfusion defects in the supine position that disappeared in the prone position were caused by attenuation, not myocardial infarction. Hence, imaging in the prone position can help to rule out ischemic heart disease for some patients admitted for SPECT with suspected but not documented ischemic heart disease. This would indicate a better prognosis and prevent unnecessary further investigations and treatment.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Markenroth Bloch, Karin, et al.
(författare)
-
Quantifying coronary sinus flow and global LV perfusion at 3T
- 2009
-
Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 9:9, s. 1-24
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract Background: Despite the large availability of 3T MR scanners and the potential of high field imaging, this technical platform has yet to prove its usefulness in the cardiac MR setting, where 1.5T remains the established standard. Global perfusion of the left ventricle, as well as the coronary flow reserve (CFR), can provide relevant diagnostic information, and MR measurements of these parameters may benefit from increased field strength. Quantitative flow measurements in the coronary sinus (CS) provide one method to nvestigate these parameters. However, the ability of newly developed faster MR sequences to measure coronary flow during a breath-hold at 3T has not been evaluated. Methods: The aim of this work was to measure CS flow using segmented phase contrast MR (PC MR)on a clinical 3T MR scanner. Parallel imaging was employed to reduce the total acquisition time. Global LV perfusion was calculated by dividing CS flow with left ventricular (LV) mass. The repeatability of the method was investigated by measuring the flow three times in each of the twelve volunteers. Phantom experiments were performed to investigate potential error sources. Results: The average CS flow was determined to 88±33 ml/min and the deduced LV perfusion was 0.60±0.22 ml/min·g, in agreement with published values. The repeatability (1-error) of the three repeated measurements in each subject was on average 84%. Conclusions: This work demonstrates that the combination of high field strength (3T), parallel imaging and segmented gradient echo sequences allow for quantification of the CS flow and global perfusion within a breath-hold.
|
|
| 6. |
|
|
| 7. |
- Razifar, Pasha, et al.
(författare)
-
Masked volume wise Principal Component Analysis of small adrenocortical tumours in dynamic [11C]-metomidate Positron Emission Tomography
- 2009
-
Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 9:6
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: In previous clinical Positron Emission Tomography (PET) studies novel approaches for application of Principal Component Analysis (PCA) on dynamic PET images such as Masked Volume Wise PCA (MVW-PCA) have been introduced. MVW-PCA was shown to be a feasible multivariate analysis technique, which, without modeling assumptions, could extract and separate organs and tissues with different kinetic behaviors into different principal components (MVW-PCs) and improve the image quality. METHODS: In this study, MVW-PCA was applied to 14 dynamic 11C-metomidate-PET (MTO-PET) examinations of 7 patients with small adrenocortical tumours. MTO-PET was performed before and 3 days after starting per oral cortisone treatment. The whole dataset, reconstructed by filtered back projection (FBP) 0-45 minutes after the tracer injection, was used to study the tracer pharmacokinetics. RESULTS: Early, intermediate and late pharmacokinetic phases could be isolated in this manner. The MVW-PC1 images correlated well to the conventionally summed image data (15-45 minutes) but the image noise in the former was considerably lower. PET measurements performed by defining "hot spot" regions of interest (ROIs) comprising 4 contiguous pixels with the highest radioactivity concentration showed a trend towards higher SUVs when the ROIs were outlined in the MVW-PC1 component than in the summed images. Time activity curves derived from "50% cut-off" ROIs based on an isocontour function whereby the pixels with SUVs between 50 to 100% of the highest radioactivity concentration were delineated, showed a significant decrease of the SUVs in normal adrenal glands and in adrenocortical adenomas after cortisone treatment. CONCLUSION: In addition to the clear decrease in image noise and the improved contrast between different structures with MVW-PCA, the results indicate that the definition of ROIs may be more accurate and precise in MVW-PC1 images than in conventional summed images. This might improve the precision of PET measurements, for instance in therapy monitoring as well as for delineation of the tumour in radiation therapy planning.
|
|
| 8. |
- Sundqvist, Olof
(författare)
-
The Question of Ancient Scandinavian Cultic Buildings : with Particular Reference to Old Norse hof
- 2009
-
Ingår i: Temenos. - 0497-1817 .- 2342-7256. ; 45:1, s. 65-84
-
Tidskriftsartikel (refereegranskat)abstract
- The article focuses On the question of ancient Scandinavian cultic buildings, with particular reference to the concept Old Norse hof. I survey the semantics of this term in written Sources, in poetic traditions, in the Sagas of the Icelanders and in place names. My hypothesis is that the term does not refer to a static phenomenon, but rather its meaning varies across different sources and contexts. It is therefore often difficult to apply it as a general concept, or to connect it with a specific type of archaeological find or structure, as has occasionally been the case in the archaeology of religion.
|
|
| 9. |
|
|
| 10. |
- Bark Persson, Anna
(författare)
-
Notes Towards Gritty Fantasy Medievalism, Temporality, and Worldbuilding
- 2022
-
Ingår i: Fafnir. - : The Finnish Society for Science Fiction and Fantasy Research. - 2342-2009. ; 9:2, s. 69-81
-
Tidskriftsartikel (refereegranskat)abstract
- This article discusses gritty fantasy, a fantasy subgenre, which was established in the early 2000s and has since gained a lot of traction. In previous research, gritty fantasy has often been understood as a deconstructive form of fantasy that draws on the barbaric Middle Ages and subverts fantasy tropes as a reaction against earlier forms of popular fantasy. I examine, rather, the genre’s relation to the medieval and its depictions of power. Drawing on queer temporality and theories on fantasy literature and worldbuilding (Mendlsohn; Roine), I approach gritty fantasy first and foremost as a form of fantasy literature, placing it within the context of speculative fiction and asking what it does as a fantastic literature.
|
|
