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  • 1.
    Abdsaleh, Shahin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wärnberg, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Azavedo, E
    Lindgren, P G
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Amini, Rose-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
    Comparison of core needle biopsy and surgical specimens in malignant breast lesions regarding histological features and hormone receptor expression2008In: Histopathology, ISSN 0309-0167, E-ISSN 1365-2559, Vol. 52, no 6, p. 773-775Article in journal (Refereed)
  • 2.
    Abdul Qadhr, Göran
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Molin, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Åström, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Suurküla, Madis
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Hagberg, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Whole-body diffusion-weighted imaging compared with FDG-PET/CT in staging of lymphoma patients2011In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 52, no 2, p. 173-180Article in journal (Refereed)
    Abstract [en]

    Background:

    Diffusion-weighted imaging (DWI) has become increasingly valuable in lymph node imaging, yet the clinical utility of this technique in the staging of lymphoma has not been established.

    Purpose:

    To compare whole-body DWI with FDG-PET/CT in the staging of lymphoma patients.

    Material and Methods:

    Thirty-one patients, eight with Hodgkin lymphoma (HL) and 23 with non-Hodgkin's lymphoma (18 aggressive and five indolent) underwent both whole-body DWI, whole-body MRI (T1W and T2W-STIR) and FDG-PET/CT. Lesions on whole-body DWI were only considered positive if they correlated with lesions on T1W and T2W-STIR images. The staging given by each technique was compared, according to the Ann Arbor staging system. Differences in staging were solved using biopsy results, and clinical and CT follow-ups as standard of reference.

    Results:

    The staging was the same for DWI and FDG-PET/CT in 28 (90.3%) patients and different in three (9.7%). Of the 28 patients with the same staging, 11 had stage IV in both techniques and 17 had stages 0-III. No HL or aggressive non-Hodgkin's lymphoma patients had different staging. Three indolent small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) lymphoma had higher staging with DWI when compared with FDG-PET/CT. One small subcutaneous breast lymphoma was not seen but all other extranodal sites were detected by both techniques.

    Conclusion:

    Whole-body DWI is a promising technique for staging of both (aggressive and indolent) non-Hodgkin's lymphoma and HL.

  • 3.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Anatomy and permeability of tumour vessels: An experimental study in nude rats with the aim of increasing the uptake of monoclonal anti-CEA antibodies in human colonic cancer1991In: Acta Radiologica, Supplement, ISSN 0365-5954, Vol. 375, no 2, p. 141-158Article in journal (Refereed)
  • 4.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    MultiHance in body MR angiography: personal experiences2004In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 14 Suppl 7, p. O52-O54Article in journal (Refereed)
  • 5.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bergqvist, David
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Vascular Surgery.
    MRA eller DSA?: Välgjord multicenterstudie ett skolexempel på hur ny medicinsk teknik bör utvärderas1996In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 93, no 41, p. 3555-3556Article in journal (Refereed)
  • 6.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Carlsson, L
    Hedin, A
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    An experimental model for pharmacokinetic studies of monoclonal antibodies in human colonic cancer1987In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 26, no 6, p. 447-451Article in journal (Refereed)
    Abstract [en]

    An experimental model consisting of athymic rats carrying human colonic tumours from cell line LS 174T in both hind legs was used. 125I-labelled anti-carcinoembryonic antigen (anti-CEA) monoclonal antibodies were injected intra-arterially (i.a.), either alone (21 rats) or together with degradable starch microspheres (6 rats). As a control, an irrelevant antibody was injected i.a., alone (6 rats) or together with microspheres (3 rats). An intra-arterial injection was given on the side bearing one tumour in each rat, while the contralateral tumour served as an 'intravenous' control. The rats were submitted to external gamma measurements daily for four days. On the fourth day they were killed and pieces from the tumours and from various organs were examined by in vitro measurements. The results indicate strong expression of CEA in LS 174T cells grafted to athymic rats. No lasting enhancement of the tumour uptake was achieved by intra-arterial injection of antibodies as compared with the control tumours.

  • 7.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Carlsson, L
    Hedin, A
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Enhanced uptake of intra-arterially injected anti-CEA monoclonal antibodies in human colonic cancer after mannitol infusion in an experimental model1987In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 26, no 6, p. 453-458Article in journal (Refereed)
    Abstract [en]

    In a previous report athymic rats carrying transplanted human colonic tumours from cell line LS 174T in both hind legs were injected intra-arterially (i.a.) with 125I-labelled anti-carcinoembryonic (anti-CEA) monoclonal antibodies. The i.a. injection was given on one side bearing a tumour in each rat, while the contralateral tumour served as an 'intravenous' control. In the same experimental model and treated in the same way, 10 rats were injected i.a. with anti-CEA monoclonal antibodies after an i.a. mannitol infusion. In both groups of rats external gamma measurements were performed daily for four days. On the fourth day the rats were killed and pieces of the tumours and of various organs were weighed and the activity was determined with a gamma-counter. The tumour uptake of antibodies was significantly enhanced after mannitol infusion.

  • 8.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Christofferson, Rolf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Paediatric Surgery.
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Vascularization of the continuous human colonic cancer cell line LS 174 T deposited subcutaneously in nude rats1988In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 96, no 8, p. 701-710Article in journal (Refereed)
    Abstract [en]

    The macro- and microvasculature of the human colonic cancer cell line LS 174 T, 2-8 weeks after subcutaneous deposition in both hind legs of congenitally athymic rats was investigated by light microscopy, angiography, and microvascular corrosion casting with analysis in a scanning electron microscope. The tumour blood vessels were connected to branches of the femoral artery. Only the outer 200-500 micron of the tumour was extensively vascularized, with several concentric, incomplete layers of tortuous vessels, resembling onion skin. Light microscopy revealed necrosis and bleeding in the centre of the tumour, especially in the older tumours, which corresponded well to the central avascularity observed in the casts. There was an increase in venular and capillary density and tortousity towards the tumour in the adjacent muscular fascia. It is concluded that the cell line LS 174 T grows invasively inwards and recruits its vessels from the nude rat host. The overall tumour vascular pattern was unorganized, suggesting limited control of new vessel formation. Extravasations of resin, which were encountered in all cast tumours, can be a rough indicator of enhanced vascular permeability.

  • 9.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Enblad, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Neurosurgery.
    Andersson, A
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    The spatial distribution of parenterally administered monoclonal antibodies against CEA in a human colorectal tumour xenograft1989In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 28, no 1, p. 81-86Article in journal (Refereed)
    Abstract [en]

    A recently developed experimental model consisting of athymic rats carrying human colonic tumours from the cell line LS 174 T in both hind legs was used. 125I-labelled anti-carcinoembryonic (anti-CEA) monoclonal antibodies were injected either intra-arterially after a bolus injection of mannitol, or intra-peritoneally with or without mannitol. On the fourth day the rats were killed and pieces from the tumours and various organs were measured in a well scintillation counter. Tumour pieces were then submitted to autoradiography and immunohistochemistry for examination of the antibody distribution at the cellular level. In all examined tumours injected with anti-CEA antibodies, most of the antibodies were located in the periphery close to fibrovascular septa. It appears, in addition to the specificity of the antibody for the CEA, that the tumour vascular permeability and anatomy are of utmost importance for tumour targeting in this experimental model with the particular antibody used.

  • 10.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Bergström, M
    Bjurling, Pernilla
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Öberg, Kjell
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Pancreatic neuroendocrine tumors: diagnosis with PET1995In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 195, no 2, p. 333-337Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    To evaluate the use of carbon-11-labeled L-dihydroxyphenylalanine (L-DOPA) and hydroxytryptophan (5-HTP) in the diagnosis of pancreatic endocrine tumors with positron emission tomography (PET).

    MATERIALS AND METHODS:

    Twenty-two consecutive patients with clinically and biochemically verified pancreatic endocrine tumors were examined with computed tomography (CT) and PET with L-DOPA alone (n = 16) or both C-11-L-DOPA and C-11-5-HTP (n = 6).

    RESULTS:

    Tumor uptake of L-DOPA was found in 11 patients, eight of whom had metastatic disease. Heterogeneity of tracer uptake was noted among different lesions in the same patient (ie, high uptake in some lesions and low uptake in others). Results in patients examined with both L-DOPA and 5-HTP correlated well, but the uptake levels of 5-HTP were higher in two of three patients with positive findings. In two additional patients, CT enabled detection of tumors not detected at PET.

    CONCLUSION:

    The current PET technique can be a valuable complement to CT in demonstration of functional pancreatic endocrine tumors, in particular, glucagonomas, but is less useful in detection of nonfunctional tumors.

  • 11.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Bergström, Mats
    Bjurling, Pernilla
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Öberg, Kjell
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Pancreatic Neuroendocrine Tumors: Diagnosis with PET1995In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 195, no 2, p. 333-337Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    To evaluate the use of carbon-11-labeled L-dihydroxyphenylalanine (L-DOPA) and hydroxytryptophan (5-HTP) in the diagnosis of pancreatic endocrine tumors with positron emission tomography (PET).

    MATERIALS AND METHODS:

    Twenty-two consecutive patients with clinically and biochemically verified pancreatic endocrine tumors were examined with computed tomography (CT) and PET with L-DOPA alone (n = 16) or both C-11-L-DOPA and C-11-5-HTP (n = 6).

    RESULTS:

    Tumor uptake of L-DOPA was found in 11 patients, eight of whom had metastatic disease. Heterogeneity of tracer uptake was noted among different lesions in the same patient (ie, high uptake in some lesions and low uptake in others). Results in patients examined with both L-DOPA and 5-HTP correlated well, but the uptake levels of 5-HTP were higher in two of three patients with positive findings. In two additional patients, CT enabled detection of tumors not detected at PET.

    CONCLUSION:

    The current PET technique can be a valuable complement to CT in demonstration of functional pancreatic endocrine tumors, in particular, glucagonomas, but is less useful in detection of nonfunctional tumors.

  • 12.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Feltelius, N
    Nyman, Rickard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Hällgren, Roger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Magnetic resonance imaging of sacroiliac joint inflammation1990In: Arthritis and Rheumatism, ISSN 0004-3591, E-ISSN 1529-0131, Vol. 33, no 12, p. 1763-1769Article in journal (Refereed)
    Abstract [en]

    A consecutive series of 27 patients with symptoms compatible with sacroiliitis underwent magnetic resonance imaging (MRI) of the sacroiliac joints. The diagnostic sensitivity of MRI was similar to that of computed tomography or conventional radiography. However, MRI seems to have the potential of providing unique information about the disease process in sacroiliitis by demonstrating abnormalities in subchondral bone and periarticular bone marrow. The results of this study suggest that early inflammatory changes in sacroiliitis occur in the subchondral structures of the sacroiliac joints.

  • 13.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Gehl, H B
    Overview of MnDPDP as a pancreas-specific contrast agent for MR imaging1997In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 38, no 4 Pt 2, p. 660-664Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    To describe and discuss previous and ongoing clinical and experimental studies with MnDPDP (Teslascan) as a pancreas-specific contrast agent for MR imaging.

    MATERIAL AND METHODS:

    All results, both experimental and clinical, applying MnDPDP as a pancreas-specific contrast agent for MR imaging, were collected.

    RESULTS:

    An increase of up to 100% in signal intensity was seen in normal pancreatic parenchyma, reaching its maximum approximately 25 min after the beginning of MnDPDP administration. Maximal enhancement was sustained for 4 h. Enhancement was only seen in the T1-weighted images. No enhancement was observed in tumours and an increase in contrast-to-noise of about 200% was obtained. The uptake of MnDPDP in pancreatitis compared with normal pancreatic parenchyma was decreased in an animal model.

    CONCLUSION:

    Improved depiction and demarcation of pancreatic tumours with MR imaging were obtained after administration of MnDPDP. MR imaging with and without MnDPDP might be valuable for staging of pancreatitis.

  • 14.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars O.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Rodenburg, J B
    Ragnarsson, A S
    Åkeson, P
    Börseth, A
    Pulmonary MR angiography with ultrasmall superparamagnetic iron oxide particles as a blood pool agent and a navigator echo for respiratory gating: pilot study1999In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 211, no 3, p. 865-869Article in journal (Refereed)
    Abstract [en]

    In nine healthy adult volunteers, pulmonary magnetic resonance angiography was performed with the blood pool agent NC100150 injection combined with respiratory gating with a navigator echo. With increasing doses of the contrast agent, higher signal intensities and vessel branch order visualization were achieved. No motion artifacts were seen. The blood pool agent NC100150 injection in combination with respiratory navigator gating permitted acquisition of high-quality MR angiograms of the pulmonary vasculature during continuous breathing.

  • 15.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Jacobson, G
    Inoperable biliary obstruction treated with percutaneously placed endoprosthesis1986In: Acta chirurgica Scandinavica, ISSN 0001-5482, Vol. 152, p. 301-303Article in journal (Refereed)
    Abstract [en]

    Biliary obstruction was treated with endoprosthetic drainage in 30 patients with pancreatic, 10 with gallbladder and 27 with biliary duct cancer, and 13 of the patients received more than one endoprosthesis. The median survival time in the respective cancer groups was 12, 10 and 9 weeks, including 6, 3 and 4 weeks spent in the patients' own homes. The patients with multiple endoprostheses had 24 weeks median survival with 22 weeks at home. Another patient, with a medically treated malignant endocrine tumour of the pancreas, lived for more than 3 years after biliary tract stenting. Complications associated with insertion of endoprosthesis were few, and clinical cholangitis occurred in seven cases. For individual patients it is difficult to predict the benefit of endoprosthetic drainage, but the procedure seems questionable if the predrainage bilirubin level is very high.

  • 16.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Magnusson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Grama, D
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Öberg, Kjell
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Lörelius, L-E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Preoperative localization of endocrine pancreatic tumours by intra-arterial dynamic computed tomography1990In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 31, no 2, p. 171-175Article in journal (Refereed)
    Abstract [en]

    Eleven patients with biochemically confirmed endocrine pancreatic tumours were examined with intra-arterial (i.a.) dynamic computed tomography (CT) and angiography preoperatively. Seven of the patients suffered from the multiple endocrine neoplasia type 1 (MEN-1) syndrome. All patients were operated upon and surgical palpation and ultrasound were the peroperative localization methods. Of the 33 tumours which were found at histopathologic analysis of the resected specimens in the 11 patients, 7 tumours in 7 patients were correctly localized by both i.a. dynamic CT and angiography. Six patients with MEN-1 syndrome had multiple tumours and this group of patients together had 28 tumours, of which 5 (18%) were localized preoperatively by both CT and angiography. I.a. dynamic CT, with the technique used by us, does not seem to improve the localization of endocrine pancreatic tumours, especially in the rare group of MEN-1 patients, as compared with angiography.

  • 17.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Malmström, Per-Uno
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Urology.
    Letocha, H
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Andersson, J
    Institutionen för läkemedelskemi; Plattformen för preklinisk PET, Uppsala university, Uppsala.
    Långström, Bengt
    Institutionen för läkemedelskemi; Plattformen för preklinisk PET, Uppsala university, Uppsala.
    Nilsson, S
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Positron emission tomography in the diagnosis and staging of urinary bladder cancer1996In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 37, no 2, p. 180-185Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    Evaluation of positron emission tomography (PET) using (18)fl 18F-2-fluoro-2-deoxy-D-glucose (18FDG) and L-methyl-11C-methionine in the diagnosis and staging of urinary bladder carcinoma.

    MATERIAL AND METHODS:

    Twenty-three patients with biopsy-proven urinary bladder carcinoma were examined with PET after intravenous injection of 11C-methionine; 2 were also examined with 18FDG. The results from the PET investigations were compared with CT or MR findings and TNM classification before and after treatment.

    RESULTS:

    The urinary excretion of 18FDG prevented distinction of the primary tumour from the surrounding tracer. With 11C-methionine it was possible to detect 18/23 primary tumours. A trend was seen, suggesting that the higher the uptake values of 11C-methionine in the tumour, the greater the tumour stage.

    CONCLUSION:

    It is possible to visualize urinary bladder tumours larger than 1 cm in diameter with PET using (11)C-methionine, but the value of the method in the staging of the lesions is not superior to conventional methods.

  • 18.
    Ahlström, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Åström, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    CT-guided bone biopsy performed by means of a coaxial biopsy system with an eccentric drill1993In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 188, no 2, p. 549-552Article in journal (Refereed)
    Abstract [en]

    Thirty-seven consecutive bone biopsies guided with computed tomography were performed in 32 patients by use of three different techniques to penetrate cortical bone and gain access to the lesion. The following instruments were used: a thin bone biopsy needle (12 biopsies), a conventional drill with an outer cannula (six biopsies), and a coaxial biopsy system that consists of a drill with an eccentric tip and an outer cannula (19 biopsies). This eccentric drill makes a hole in the bone larger than the diameter of the cannula and thereby makes it easy to advance the cannula over the drill until the cannula is anchored in the bone. One can then obtain multiple samples through the cannula. The thin bone biopsy needle could not penetrate thick (8 mm thick) cortical bone. The outer cannula was not anchored in the bone when the conventional drill was used. In 16 biopsies, the new coaxial biopsy system penetrated cortical bone with a thickness of 1-8 mm and was anchored there, and lesion samples were obtained through the anchored cannula.

  • 19.
    Amini, Hashem
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Axelsson, Ove
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Second trimester fetal magnetic resonance imaging improves diagnosis of non-central nervous system anomalies2011In: Acta Obstetricia et Gynecologica Scandinavica, ISSN 0001-6349, E-ISSN 1600-0412, Vol. 90, no 4, p. 380-389Article in journal (Refereed)
    Abstract [en]

    Objectives. To evaluate the additional information of second trimester magnetic resonance imaging (MRI) compared to ultrasound in fetuses with identified or suspected non-CNS anomalies and to study the clinical impact of the MRI information on pregnancy management. Design. Prospective study during 2003-2007. The fetal MRI examination was planned to be performed within three days after the ultrasound. Setting. Uppsala University hospital. Material and methods. Sixty-three women, where the second trimester ultrasound identified or raised suspicion of fetal anomalies were included. Ultrasound was compared to MRI in relation to the final diagnosis, which was based on the assessment of all available data including post-partum clinical follow-up and autopsy results. Main outcome measures. Evaluation of the additional information gained from MRI and the consequences it had on pregnancy management. Results. The mean interval between ultrasound and MRI was 2.6 days (range 0-15). In 42 (67%) cases MRI was performed within three days. All MRI examinations were assessable. In 43 (68%) fetuses MRI provided no additional information, in 17 (27%) MRI added information without changing the management and in three (5%) MRI provided additional information which changed the management. All these three cases had oligohydramnios. In all six cases of diaphragmatic hernia MRI provided additional information. Conclusions. Fetal MRI of non-CNS anomalies in the second trimester seems to be a valuable adjunct to ultrasound diagnosis of non-CNS anomalies, especially in cases of oligohydramnios and diaphragmatic hernia.

  • 20.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Johansson, Silvia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikehult, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Education in Nursing.
    18F-Fluorid-PET-CT: Patient expectations and experiences2013In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 40, no Suppl. 2, p. S510-S510Article in journal (Other academic)
  • 21.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Johansson, Silvia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikehult, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Education in Nursing.
    Patient expectations and experiences of 18F-FDG-PET-CT: A need for improvement2012In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 39, no S2, p. S207-S207Article in journal (Other academic)
  • 22. Andersson, Jesper L
    et al.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Valind, Sven
    A method for coregistration of PET and MR brain images1995In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 36, no 7, p. 1307-1315Article in journal (Refereed)
    Abstract [en]

    Combining MRI morphological data with functional PET data offers significant advantages in research as well as in many clinical situations. Automatic methods are needed, however, to coregister the data from the two modalities.

    METHODS:

    Simulated PET images were created by simple and automatic segmentation of MR images followed by the assignment of different uptake values to various tissue types. The simulated PET images were registered to actual PET images using a pixel-by-pixel, PET-PET registration method. The transformation matrix was then applied to the MR images. The method was used to register MRI data to PET transmission scans and emission scans obtained with FDG, nomifensine and raclopride. Validation was performed by comparing the results to those obtained by matching internal points manually defined in both volumes.

    RESULTS:

    Emission and transmission PET images were successfully registered to MR data. Comparison to the manual method indicated a registration accuracy on the order of 1-2 mm in each direction. No difference in accuracy between the different tracers was found. The error sensitivity for the method's assumptions seemed to be sufficiently low to allow complete automation of the method.

    CONCLUSION:

    We present a rapid, robust and fully automated method to register PET and MR brain images with sufficient accuracy for most clinical applications.

  • 23.
    Andersson, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Methods for automatic analysis of glucose uptake in adipose tissue using quantitative PET/MRI data2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Brown adipose tissue (BAT) is the main tissue involved in non-shivering heat production. A greater understanding of BAT could possibly lead to new ways of prevention and treatment of obesity and type 2 diabetes. The increasing prevalence of these conditions and the problems they cause society and individuals make the study of the subject important.

    An ongoing study performed at the Turku University Hospital uses images acquired using PET/MRI with 18F-FDG as the tracer. Scans are performed on sedentary and athlete subjects during normal room temperature and during cold stimulation. Sedentary subjects then undergo scanning during cold stimulation again after a six weeks long exercise training intervention. This degree project used images from this study.

    The objective of this degree project was to examine methods to automatically and objectively quantify parameters relevant for activation of BAT in combined PET/MRI data. A secondary goal was to create images showing glucose uptake changes in subjects from images taken at different times.

    Parameters were quantified in adipose tissue directly without registration (image matching), and for neck scans also after registration. Results for the first three subjects who have completed the study are presented. Larger registration errors were encountered near moving organs and in regions with less information.

    The creation of images showing changes in glucose uptake seem to be working well for the neck scans, and somewhat well for other sub-volumes. These images can be useful for identification of BAT. Examples of these images are shown in the report.

  • 24.
    Arakelian, Erebouni
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Colorectal Surgery.
    Torkzad, Michael R.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bergman, Antonina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Rubertsson, Sten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Mahteme, Haile
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Colorectal Surgery.
    Pulmonary influences on early postoperative recovery in patients after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy treatment2011In: Anesthesia and Analgesia, ISSN 0003-2999, E-ISSN 1526-7598Article in journal (Other academic)
  • 25.
    Arakelian, Erebouni
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Education in Nursing.
    Torkzad, Michael R.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bergman, Antonina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Rubertsson, Sten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Mahteme, Haile
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Colorectal Surgery.
    Pulmonary influences on early post-operative recovery in patients after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy treatment: a retrospective study2012In: World Journal of Surgical Oncology, ISSN 1477-7819, E-ISSN 1477-7819, Vol. 10, p. 258-Article in journal (Refereed)
    Abstract [en]

    Background: The combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a curative treatment option for peritoneal carcinomatosis (PC). There have been few studies on the pulmonary adverse events (AEs) affecting patient recovery after this treatment, thus this study investigated these factors. Methods: Between January 2005 and December 2006, clinical data on all pulmonary AEs and the recovery progress were reviewed for 76 patients with after CRS and HIPEC. Patients with pulmonary interventions (thoracocenthesis and chest tubes) were compared with the non-intervention patients. Two senior radiologists, blinded to the post-operative clinical course, separately graded the occurrence of pulmonary AEs. Results: Of the 76 patients, 6 had needed thoracocentesis and another 6 needed chest tubes. There were no differences in post-operative recovery between the intervention and non-intervention groups. The total number of days on mechanical ventilation, the length of stay in the intensive care unit, total length of hospital stay, tumor burden, and an American Society of Anesthesiologists (ASA) grade of greater than 2 were correlated with the occurrence of atelectasis and pleural effusion. Extensive atelectasis (grade 3 or higher) was seen in six patients, major pleural effusion (grade 3) in seven patients, and signs of heart failure (grade 1-2) in nine patients. Conclusions: Clinical and radiological post-operative pulmonary AEs are common after CRS and HIPEC. However, most of the pulmonary AEs did not affect post-operative recovery.

  • 26. Axelsson, Jan
    et al.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    The 2D Hotelling filter - a quantitative noise-reducing principal-component filter for dynamic PET data, with applications in patient dose reduction.2013In: BMC Medical Physics, ISSN 1756-6649, E-ISSN 1756-6649, Vol. 13Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: In this paper we apply the principal-component analysis filter (Hotelling filter) to reduce noise from dynamic positron-emission tomography (PET) patient data, for a number of different radio-tracer molecules. We furthermore show how preprocessing images with this filter improves parametric images created from such dynamic sequence.We use zero-mean unit variance normalization, prior to performing a Hotelling filter on the slices of a dynamic time-series. The Scree-plot technique was used to determine which principal components to be rejected in the filter process. This filter was applied to [11C]-acetate on heart and head-neck tumors, [18F]-FDG on liver tumors and brain, and [11C]-Raclopride on brain. Simulations of blood and tissue regions with noise properties matched to real PET data, was used to analyze how quantitation and resolution is affected by the Hotelling filter. Summing varying parts of a 90-frame [18F]-FDG brain scan, we created 9-frame dynamic scans with image statistics comparable to 20 MBq, 60 MBq and 200 MBq injected activity. Hotelling filter performed on slices (2D) and on volumes (3D) were compared.

    RESULTS: The 2D Hotelling filter reduces noise in the tissue uptake drastically, so that it becomes simple to manually pick out regions-of-interest from noisy data. 2D Hotelling filter introduces less bias than 3D Hotelling filter in focal Raclopride uptake. Simulations show that the Hotelling filter is sensitive to typical blood peak in PET prior to tissue uptake have commenced, introducing a negative bias in early tissue uptake. Quantitation on real dynamic data is reliable. Two examples clearly show that pre-filtering the dynamic sequence with the Hotelling filter prior to Patlak-slope calculations gives clearly improved parametric image quality. We also show that a dramatic dose reduction can be achieved for Patlak slope images without changing image quality or quantitation.

    CONCLUSIONS: The 2D Hotelling-filtering of dynamic PET data is a computer-efficient method that gives visually improved differentiation of different tissues, which we have observed improve manual or automated region-of-interest delineation of dynamic data. Parametric Patlak images on Hotelling-filtered data display improved clarity, compared to non-filtered Patlak slope images without measurable loss of quantitation, and allow a dramatic decrease in patient injected dose.

  • 27.
    Bajic, Dragan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Canto Moreira, Nuno
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Raininko, Raili
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Development of the hippocampal region demonstrated on fetal MRI: A preliminary report2011In: NRJ Digital, ISSN 2239-7493, Vol. 1, no 12, p. 555-557Article in journal (Refereed)
    Abstract [en]

    Coronal slices of three fetal MRIs performed post mortem and 37 performed in utero, all without intracranial pathology, was assessed. Progress of the hippocampal inversion was analyzed, the left and right sides were compared and occurrence of the collateral sulcus was revealed. The fetuses in the post mortem examinations were at gestation weeks (GW) 17-18 and in the in utero examinations at GW 19-35. The symmetric development of the hippocampal sulcus was revealed in 26 subjects and asymmetric in 14. The non-ovoid hippocampal formation could be evaluated at GW 24 at earliest and an ovoid hippocampus at GW 29. The collateral sulcus could be recognized at GW 17 in post mortem and at GW 22 in in utero examinations. From GW 29 onwards it was seen in all fetuses and it was symmetric in all but one case. Evaluation of the hippocampi is difficult on fetal MRI, especially in in utero examinations. The hippocampal development is not fulfilled at GW 21 as presumed. There is a wide temporal variation in the development of the hippocampal region, and the developmental process does not progress simultaneously in the right and left side of the same individual.

  • 28.
    Bajic, Dragan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Canto Moreira, Nuno
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Raininko, Raili
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Hippocampal development demonstrated by fetal MRI. Asymmetric development is common.2011In: Insights into Imaging, Vol. 2, no Suppl 1, p. B-831-Article in journal (Refereed)
  • 29. Balleyguier, Corinne
    et al.
    Sala, E.
    Da Cunha, T.
    Bergman, Antonina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Brkljacic, B.
    Danza, F.
    Forstner, R.
    Hamm, B.
    Kubik-Huch, R.
    Lopez, C.
    Manfredi, R.
    McHugo, J.
    Oleaga, L.
    Togashi, K.
    Kinkel, K.
    Staging of uterine cervical cancer with MRI: guidelines of the European Society of Urogenital Radiology2011In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 21, no 5, p. 1102-1110Article in journal (Refereed)
    Abstract [en]

    Objective: To design clear guidelines for the staging and follow-up of patients with uterine cervical cancer, and to provide the radiologist with a framework for use in multidisciplinary conferences. Methods: Guidelines for uterine cervical cancer staging and follow-up were defined by the female imaging subcommittee of the ESUR (European Society of Urogenital Radiology) based on the expert consensus of imaging protocols of 11 leading institutions and a critical review of the literature. Results: The results indicated that high field Magnetic Resonance Imaging (MRI) should include at least two T2-weighted sequences in sagittal, axial oblique or coronal oblique orientation (short and long axis of the uterine cervix) of the pelvic content. Axial T1-weighted sequence is useful to detect suspicious pelvic and abdominal lymph nodes, and images from symphysis to the left renal vein are required. The intravenous administration of Gadolinium-chelates is optional but is often required for small lesions (< 2 cm) and for follow-up after treatment. Diffusion-weighted sequences are optional but are recommended to help evaluate lymph nodes and to detect a residual lesion after chemoradiotherapy. Conclusions: Expert consensus and literature review lead to an optimized MRI protocol to stage uterine cervical cancer. MRI is the imaging modality of choice for preoperative staging and follow-up in patients with uterine cervical cancer.

  • 30.
    Bannbers, Elin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology.
    Gingnell, Malin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology. Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Engman, Jonas
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Morell, Arvid
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Comasco, Erika
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Kask, Kristiina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology.
    Garavan, Hugh
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Sundström Poromaa, Inger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology.
    The effect of premenstrual dysphoric disorder and menstrual cycle phase on brain activity during response inhibition2012In: Journal of Affective Disorders, ISSN 0165-0327, E-ISSN 1573-2517, Vol. 142, no 1-3, p. 347-350Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Premenstrual dysphoric disorder (PMDD) has generally not been associated with impulsive behavior. However, some studies suggest that women with PMDD have higher impulsivity scores than healthy controls and that brain activity during response inhibition may vary across the menstrual cycle. Therefore, our aim was to unravel potentially important cognitive aspects of PMDD by investigating brain activity during response inhibition in women with PMDD and healthy controls in relation to menstrual cycle phase.

    METHODS:

    Fourteen PMDD patients and 13 healthy controls performed a Go/NoGo task to measure brain activity during response inhibition by use of event-related functional magnetic resonance imaging.

    RESULTS:

    Women with PMDD displayed decreased activity during both menstrual cycle phases compared to healthy controls in several task-related parietal areas. A significant group by phase interactions was found in the left insula, driven by enhanced activity among healthy controls in the follicular phase and by enhanced insula activity during the luteal phase among PMDD patients.

    LIMITATIONS:

    The limitations of the present study are the relatively limited sample size, the relatively small number of NoGo trials and the lack of a baseline contrast for the NoGo trials.

    CONCLUSIONS:

    During response inhibition women with PMDD have reduced activity in areas associated with attention and motor function which is unrelated to menstrual cycle phase. Insular cortex activity, involved in both affective and cognitive processing, was significantly activated during the luteal phase among PMDD women. These findings are relevant for the understanding of how ovarian steroids influence mood symptoms in women.

  • 31.
    Bannbers, Elin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Gingnell, Malin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology. Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Engman, Jonas
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Morell, Arvid
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Sylvén, Sara
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Skalkidou, Alkistis
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Kask, Kristiina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Bäckström, Torbjörn
    Department of Clinical Science, Obstetrics and Gynecology, Umeå University, Umeå, Sweden.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Sundström Poromaa, Inger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Prefrontal activity during response inhibition decreases over time in the postpartum period2013In: Behavioural Brain Research, ISSN 0166-4328, E-ISSN 1872-7549, Vol. 241, no 1, p. 132-138Article in journal (Refereed)
    Abstract [en]

    The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48hours of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in response inhibition performance were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted.

  • 32.
    Bannbers, Elin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Kask, Kristiina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Risbrough, Victoria
    Department of Psychiatry, University of California, San Diego, CA, USA.
    Sundström Poromaa, Inger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Patients with premenstrual dysphoric disorder have increased startle modulation during anticipation in the late luteal phase period in comparison to control subjects2011In: Psychoneuroendocrinology, ISSN 0306-4530, E-ISSN 1873-3360, Vol. 36, no 8, p. 1184-1192Article in journal (Refereed)
    Abstract [en]

    The acoustic startle response (ASR) is a withdrawal reflex to sudden or noxious auditory stimuli and, most importantly, an unbiased measure of emotional processing of appetitive and aversive stimuli. By exposing subjects to fearful situations, such as aversive pictures, the ASR may be enhanced, suggesting that amygdala modulates the startle circuit during threat situations. As one previous study, investigating affective modulation of the ASR in women with premenstrual dysphoric disorder (PMDD), discovered no difference during picture viewing it is possible that the mood changes observed in PMDD relate to anxious anticipation rather than to direct stimulus responding. Hence we sought to examine the effects of PMDD on picture anticipation and picture response.

    Sixteen PMDD patients and 16 controls watched slide shows containing pleasant and unpleasant pictures and positive and negative anticipation stimuli during the follicular and luteal phase of the menstrual cycle. Simultaneously, semi-randomized startle probes (105dB) were delivered and the ASR was assessed with electromyography.

    Compared with control subjects, PMDD patients displayed an enhanced startle modulation by positive and negative anticipation stimuli in the luteal phase of the menstrual cycle. This finding was mainly driven by increased modulation in the luteal phase in comparison to the follicular phase among PMDD patients but also by an increased modulation in patients compared to controls during luteal phase. This suggests that the neural circuits underlying response to emotional anticipation are more sensitive during this period and emphasize the need of examining the neural correlates of anticipatory processes in women with PMDD.

  • 33. Barenius, Björn
    et al.
    Ponzer, Sari
    Shalabi, Adel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bujak, Robert
    Norlén, Louise
    Eriksson, Karl
    Increased risk of osteoarthritis after anterior cruciate ligament reconstruction: a 14-year follow-up study of a randomized controlled trial.2014In: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 42, no 5Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The reported prevalence of radiological osteoarthritis (OA) after anterior cruciate ligament (ACL) reconstruction varies from 10% to 90%. Purpose/

    HYPOTHESIS: To report the prevalence of OA after ACL reconstruction and to compare the OA prevalence between quadrupled semitendinosus tendon (ST) and bone-patellar tendon-bone (BPTB) grafts. The hypothesis was that there would be no difference in OA prevalence between the graft types. The secondary aim was to study whether patient characteristics and additional injuries were associated with long-term outcomes.

    STUDY DESIGN: Randomized controlled trial; Level of evidence, 1.

    METHODS: Radiological examination results, Tegner activity levels, and Knee injury and Osteoarthritis Outcome Score (KOOS) values were determined in 135 (82%) of 164 patients at a mean of 14 years after ACL reconstruction randomized to an ST or a BPTB graft. Osteoarthritis was defined according to a consensus by at least 2 of 3 radiologists of Kellgren-Lawrence grade ≥2. Using regression analysis, graft type, sex, age, overweight, time between injury and reconstruction, additional meniscus injury, and a number of other variables were assessed as risk factors for OA 14 years after ACL reconstruction.

    RESULTS: Osteoarthritis of the medial compartment was most frequent, with 57% of OA cases in the ACL-reconstructed knee and 18% of OA cases in the contralateral knee (P < .001). There was no difference between the graft types: 49% of OA of the medial compartment for BPTB grafts and 65% for ST grafts (P = .073). The KOOS results were lower for patients with OA in all subscales, indicating that OA was symptomatic. No difference in the KOOS between the graft types was found. Meniscus resection was a strong risk factor for OA of the medial compartment (odds ratio, 3.6; 95% CI, 1.4-9.3) in the multivariable logistic regression analysis.

    CONCLUSION: A 3-fold increased prevalence of OA was found after an ACL injury treated with reconstruction compared with the contralateral healthy knee. No differences in the prevalence of OA between the BPTB and quadrupled ST reconstructions were found. An initial meniscus resection was a strong risk factor for OA; the time between injury and reconstruction was not.

  • 34. Beets-Tan, Regina G. H.
    et al.
    Lambregts, Doenja M. J.
    Maas, Monique
    Bipat, Shandra
    Barbaro, Brunella
    Caseiro-Alves, Filipe
    Curvo-Semedo, Luis
    Fenlon, Helen M.
    Gollub, Marc J.
    Gourtsoyianni, Sofia
    Halligan, Steve
    Hoeffel, Christine
    Kim, Seung Ho
    Laghi, Andrea
    Maier, Andrea
    Rafaelsen, Soren R.
    Stoker, Jaap
    Taylor, Stuart A.
    Torkzad, Michael R.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Blomqvist, Lennart
    Magnetic resonance imaging for the clinical management of rectal cancer patients: recommendations from the 2012 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting2013In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 23, no 9, p. 2522-2531Article in journal (Refereed)
    Abstract [en]

    To develop guidelines describing a standardised approach regarding the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. A consensus meeting of 14 abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) was conducted following the RAND-UCLA Appropriateness Method. Two independent (non-voting) chairs facilitated the meeting. Two hundred and thirty-six items were scored by participants for appropriateness and classified subsequently as appropriate or inappropriate (defined by a parts per thousand yen 80 % consensus) or uncertain (defined by < 80 % consensus). Items not reaching 80 % consensus were noted. Consensus was reached for 88 % of items: recommendations regarding hardware, patient preparation, imaging sequences, angulation, criteria for MRI assessment and MRI reporting were constructed from these. These expert consensus recommendations can be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI. These guidelines recommend standardised imaging for staging and restaging of rectal cancer. The guidelines were constructed through consensus amongst 14 abdominal imaging experts. Consensus was reached by in 88 % of 236 items discussed.

  • 35.
    Benedict, Christian
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Brooks, Samantha J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Burgos, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kempton, Matthew J
    Nordenskjöld, Richard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nylander, Ruta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Craft, Suzanne
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Impaired Insulin Sensitivity as Indexed by the HOMA Score Is Associated With Deficits in Verbal Fluency and Temporal Lobe Gray Matter Volume in the Elderly2012In: Diabetes Care, ISSN 0149-5992, E-ISSN 1935-5548, Vol. 35, no 3, p. 488-494Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE

    Impaired insulin sensitivity is linked to cognitive deficits and reduced brain size. However, it is not yet known whether insulin sensitivity involves regional changes in gray matter volume. Against this background, we examined the association between insulin sensitivity, cognitive performance, and regional gray matter volume in 285 cognitively healthy elderly men and women aged 75 years from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study.

    RESEARCH DESIGN AND METHODS

    Insulin sensitivity was calculated from fasting serum insulin and plasma glucose determinations using the homeostasis model assessment of insulin resistance (HOMA-IR) method. Cognitive performance was examined by a categorical verbal fluency. Participants also underwent a magnetic resonance imaging (MRI) brain scan. Multivariate analysis using linear regression was conducted, controlling for potential confounders (sex, education, serum LDL cholesterol, mean arterial blood pressure, and abdominal visceral fat volume).

    RESULTS

    The HOMA-IR was negatively correlated with verbal fluency performance, brain size (S1), and temporal lobe gray matter volume in regions known to be involved in speech production (Brodmann areas 21 and 22, respectively). No such effects were observed when examining diabetic (n = 55) and cognitively impaired (n = 27) elderly subjects as separate analyses.

    CONCLUSIONS

    These cross-sectional findings suggest that both pharmacologic and lifestyle interventions improving insulin signaling may promote brain health in late life but must be confirmed in patient studies.

  • 36.
    Benedict, Christian
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Brooks, Samantha J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nordenskjöld, Richard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Burgos, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Le Grevès, Madeleine
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Association between physical activity and brain health in older adults2013In: Neurobiology of Aging, ISSN 0197-4580, E-ISSN 1558-1497, Vol. 34, no 1, p. 83-90Article in journal (Refereed)
    Abstract [en]

    In the present cross-sectional study, we examined physical activity (PA) and its possible association with cognitive skills and brain structure in 331 cognitively healthy elderly. Based on the number of self-reported light and hard activities for at least 30 minutes per week, participants were assigned to 4 groups representing different levels of PA. The cognitive skills were assessed by the Mini Mental State Examination score, a verbal fluency task, and the Trail-making test as a measure of visuospatial orientation ability. Participants also underwent a magnetic resonance imaging of the brain. Multiple regression analysis revealed that greater PA was associated with a shorter time to complete the Trail-making test, and higher levels of verbal fluency. Further, the level of self-reported PA was positively correlated with brain volume, white matter, as well as a parietal lobe gray matter volume, situated bilaterally at the precuneus. These present cross-sectional results indicate that PA is a lifestyle factor that is linked to brain structure and function in late life.

  • 37.
    Benedict, Christian
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Brooks, Samantha J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    O'Daly, Owen G
    Almèn, Markus S
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Morell, Arvid
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Åberg, Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Gingnell, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Schultes, Bernd
    Hallschmid, Manfred
    Broman, Jan-Erik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Acute Sleep Deprivation Enhances the Brain's Response to Hedonic Food Stimuli: An fMRI Study2012In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 97, no 3, p. E443-447Article in journal (Refereed)
    Abstract [en]

    Context:

    There is growing recognition that a large number of individuals living in Western society are chronically sleep deprived. Sleep deprivation is associated with an increase in food consumption and appetite. However, the brain regions that are most susceptible to sleep deprivation-induced changes when processing food stimuli are unknown.

    Objective:

    Our objective was to examine brain activation after sleep and sleep deprivation in response to images of food.

    Intervention:

    Twelve normal-weight male subjects were examined on two sessions in a counterbalanced fashion: after one night of total sleep deprivation and one night of sleep. On the morning after either total sleep deprivation or sleep, neural activation was measured by functional magnetic resonance imaging in a block design alternating between high- and low-calorie food items. Hunger ratings and morning fasting plasma glucose concentrations were assessed before the scan, as were appetite ratings in response to food images after the scan.

    Main Outcome Measures:

    Compared with sleep, total sleep deprivation was associated with an increased activation in the right anterior cingulate cortex in response to food images, independent of calorie content and prescan hunger ratings. Relative to the postsleep condition, in the total sleep deprivation condition, the activation in the anterior cingulate cortex evoked by foods correlated positively with postscan subjective appetite ratings. Self-reported hunger after the nocturnal vigil was enhanced, but importantly, no change in fasting plasma glucose concentration was found.

    Conclusions:

    These results provide evidence that acute sleep loss enhances hedonic stimulus processing in the brain underlying the drive to consume food, independent of plasma glucose levels. These findings highlight a potentially important mechanism contributing to the growing levels of obesity in Western society.

  • 38. Bense, Laszlo
    et al.
    Eklund, Gunnar
    Jorulf, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Farkas, Arpad
    Balashazy, Imre
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Krebsz, Adam
    Gergely Madas, Balazs
    Eden Strindberg, Jerker
    Right main bronchus perforation detected by 3D-image2011In: BMJ case reports, ISSN 1757-790XArticle in journal (Refereed)
    Abstract [en]

    A male metal worker, who has never smoked, contracted debilitating dyspnoea in 2003 which then deteriorated until 2007. Spirometry and chest x-rays provided no diagnosis. A 3D-image of the airways was reconstructed from a high-resolution CT (HRCT) in 2007, showing peribronchial air on the right side, mostly along the presegmental airways. After digital subtraction of the image of the peribronchial air, a hole on the cranial side of the right main bronchus was detected. The perforation could be identified at the re-examination of HRCTs in 2007 and 2009, but not in 2010 when it had possibly healed. The occupational exposure of the patient to evaporating chemicals might have contributed to the perforation and hampered its healing. A 3D HRCT reconstruction should be considered to detect bronchial anomalies, including wall-perforation, when unexplained dyspnoea or other chest symptoms call for extended investigation.

  • 39.
    Berglund, David
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Transplantation Surgery.
    Bergqvist, David
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Vascular Surgery.
    Lundqvist, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Magnusson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Sedigh, Amir
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Transplantation Surgery.
    Bäckman, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Transplantation Surgery.
    Biglarnia, Ali-Reza
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Transplantation Surgery.
    Vascular reconstruction using allogeneic homografts in a renal transplant patient with pseudoaneurysm and infected vascular prosthesis2012In: Transplantation, ISSN 0041-1337, E-ISSN 1534-6080, Vol. 93, no 4, p. e15-e16Article in journal (Refereed)
  • 40.
    Berglund, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Separation of Water and Fat Signal in Magnetic Resonance Imaging: Advances in Methods Based on Chemical Shift2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Magnetic resonance imaging (MRI) is one of the most important diagnostic tools of modern healthcare. The signal in medical MRI predominantly originates from water and fat molecules. Separation of the two components into water-only and fat-only images can improve diagnosis, and is the premier non-invasive method for measuring the amount and distribution of fatty tissue.

    Fat-water imaging (FWI) enables fast fat/water separation by model-based estimation from chemical shift encoded data, such as multi-echo acquisitions. Qualitative FWI is sufficient for visual separation of the components, while quantitative FWI also offers reliable estimates of the fat percentage in each pixel. The major problems of current FWI methods are long acquisition times, long reconstruction times, and reconstruction errors that degrade image quality.

    In this thesis, existing FWI methods were reviewed, and novel fully automatic methods were developed and evaluated, with a focus on fast 3D image reconstruction. All MRI data was acquired on standard clinical scanners.

    A triple-echo qualitative FWI method was developed for the specific application of 3D whole-body imaging. The method was compared with two reference methods, and demonstrated superior image quality when evaluated in 39 volunteers.

    The problem of qualitative FWI by dual-echo data with unconstrained echo times was solved, allowing faster and more flexible image acquisition than conventional FWI. Feasibility of the method was demonstrated in three volunteers and the noise performance was evaluated.

    Further, a quantitative multi-echo FWI method was developed. The signal separation was based on discrete whole-image optimization. Fast 3D image reconstruction with few reconstruction errors was demonstrated by abdominal imaging of ten volunteers.

    Lastly, a method was proposed for quantitative mapping of average fatty acid chain length and degree of saturation. The method was validated by imaging different oils, using gas-liquid chromatography (GLC) as the reference. The degree of saturation agreed well with GLC, and feasibility of the method was demonstrated in the thigh of a volunteer.

    The developed methods have applications in clinical settings, and are already being used in several research projects, including studies of obesity, dietary intervention, and the metabolic syndrome.

    List of papers
    1. Three-point Dixon method enables whole-body water and fat imaging of obese subjects
    Open this publication in new window or tab >>Three-point Dixon method enables whole-body water and fat imaging of obese subjects
    2010 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 63, no 6, p. 1659-1668Article in journal (Refereed) Published
    Abstract [en]

    Dixon imaging techniques derive chemical shift-separated water and fat images, enabling the quantification of fat content and forming an alternative to fat suppression. Whole-body Dixon imaging is of interest in studies of obesity and the metabolic syndrome, and possibly in oncology. A three-point Dixon method is proposed where two solutions are found analytically in each voxel. The true solution is identified by a multiseed three-dimensional region-growing scheme with a dynamic path, allowing confident regions to be solved before unconfident regions, such as background noise. 2 pi-Phase unwrapping is not required. Whole-body datasets (256 x 184 x 252 voxels) were collected from 39 subjects (body mass index 19.8-45.4 kg/m(2)), in a mean scan time of 5 min 15 sec. Water and fat images were reconstructed offline, using the proposed method and two reference methods. The resulting images were subjectively graded on a four-grade scale by two radiologists, blinded to the method used. The proposed method was found superior to the reference methods. It exclusively received the two highest grades, implying that only mild reconstruction failures were found. The computation time for a whole-body dataset was 1 min 51.5 sec +/- 3.0 sec. It was concluded that whole-body water and fat imaging is feasible even for obese subjects, using the proposed method.

    Keywords
    three-point Dixon, whole-body MRI, water and fat separation, chemical shift imaging, fat suppression
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:uu:diva-129498 (URN)10.1002/mrm.22385 (DOI)000278164400026 ()20512869 (PubMedID)
    Available from: 2010-08-17 Created: 2010-08-17 Last updated: 2017-12-12Bibliographically approved
    2. Two-point dixon method with flexible echo times
    Open this publication in new window or tab >>Two-point dixon method with flexible echo times
    2011 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 65, no 4, p. 994-1004Article in journal (Refereed) Published
    Abstract [en]

    The two-point Dixon method is a proton chemical shift imaging technique that produces separated water-only and fat-only images from a dual-echo acquisition. It is shown how this can be achieved without the usual constraints on the echo times. A signal model considering spectral broadening of the fat peak is proposed for improved water/fat separation. Phase errors, mostly due to static field inhomogeneity, must be removed prior to least-squares estimation of water and fat. To resolve ambiguity of the phase errors, a corresponding global optimization problem is formulated and solved using a message-passing algorithm. It is shown that the noise in the water and fat estimates matches the Cramér-Rao bounds, and feasibility is demonstrated for in vivo abdominal breath-hold imaging. The water-only images were found to offer superior fat suppression compared with conventional spectrally fat suppressed images.

    Keywords
    chemical shift imaging, fat suppression, two-point Dixon, water and fat separation
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:uu:diva-150936 (URN)10.1002/mrm.22679 (DOI)000288612000011 ()21413063 (PubMedID)
    Available from: 2011-04-08 Created: 2011-04-08 Last updated: 2017-12-11Bibliographically approved
    3. Three-dimensional water/fat separation and T2* estimation based on whole-image optimization: application in breathhold liver imaging at 1.5 T
    Open this publication in new window or tab >>Three-dimensional water/fat separation and T2* estimation based on whole-image optimization: application in breathhold liver imaging at 1.5 T
    2012 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 67, no 6, p. 1684-1693Article in journal (Refereed) Published
    Abstract [en]

    The chemical shift of water and fat resonances in proton MRI allows separation of water and fat signal from chemical shift encoded data. This work describes an automatic method that produces separate water and fat images as well as quantitative maps of fat signal fraction and T2* from complex multi-echo gradient recalled datasets. Accurate water and fat separation is challenging due to signal ambiguity at the voxel level. Whole-image optimization can resolve this ambiguity, but might be computationally demanding, especially for three-dimensional (3D) data. In this work, periodicity of the model fit residual as a function of the off-resonance was utilized to modify a previously proposed formulation of the problem. This gives a smaller solution space and allows rapid optimization. Feasibility and accurate separation of water and fat signal was demonstrated in breathhold 3D liver imaging of ten volunteer subjects, with both acquisition and reconstruction times below 20 seconds.

    Keywords
    water and fat separation, chemical shift imaging, quantitative MRI, liver fat, T2* mapping, QPBO
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:uu:diva-158097 (URN)10.1002/mrm.23185 (DOI)000304086000020 ()22189760 (PubMedID)
    Available from: 2011-08-31 Created: 2011-08-31 Last updated: 2017-12-08Bibliographically approved
    4. Model-based mapping of fat unsaturation and chain length by chemical shift imaging: phantom validation and in vivo feasibility
    Open this publication in new window or tab >>Model-based mapping of fat unsaturation and chain length by chemical shift imaging: phantom validation and in vivo feasibility
    2012 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 68, no 6, p. 1815-1827Article in journal (Refereed) Published
    Abstract [en]

    Knowledge about the triglyceride (fat) 1H spectrum enables quantitative determination of several triglyceride characteristics. This work describes a model-based chemical shift imaging method that separates water and fat signal and provides maps of three triglyceride quantities: fatty acid carbon chain length (CL), number of double bond pairs (ndb), and number of methylene-interrupted double bonds (nmidb). The method was validated by imaging a phantom containing ten different oils using 1.5 T and 3.0 T clinical scanners, with gas-liquid chromatography (GLC) as reference. Repeated acquisitions demonstrated high reproducibility of the method. Statistical tests of correlation and linear regression were performed to examine the accuracy of the method. Significant correlation was found at both field strengths for all three quantities, and high correlation (r2 > 0.96) was found for measuring ndb and nmidb. Feasibility of the method for in vivo imaging of the thigh was demonstrated at both field strengths. The estimates of ndb and nmidb in subcutaneous adipose tisse were in agreement with literature values, while CL appears overestimated. The method has potential use in large-scale cross-sectional and longitudinal studies of triglyceride composition, and its relation to diet and various diseases.

    Keywords
    water/fat separation, chemical shift imaging, quantitative MRI, fat unsaturation, triglyceride mapping, fatty acid composition
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Identifiers
    urn:nbn:se:uu:diva-158098 (URN)10.1002/mrm.24196 (DOI)000311398600015 ()22334300 (PubMedID)
    Available from: 2011-08-31 Created: 2011-08-31 Last updated: 2017-12-08Bibliographically approved
  • 41.
    Berglund, Johan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Two-point dixon method with flexible echo times2011In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 65, no 4, p. 994-1004Article in journal (Refereed)
    Abstract [en]

    The two-point Dixon method is a proton chemical shift imaging technique that produces separated water-only and fat-only images from a dual-echo acquisition. It is shown how this can be achieved without the usual constraints on the echo times. A signal model considering spectral broadening of the fat peak is proposed for improved water/fat separation. Phase errors, mostly due to static field inhomogeneity, must be removed prior to least-squares estimation of water and fat. To resolve ambiguity of the phase errors, a corresponding global optimization problem is formulated and solved using a message-passing algorithm. It is shown that the noise in the water and fat estimates matches the Cramér-Rao bounds, and feasibility is demonstrated for in vivo abdominal breath-hold imaging. The water-only images were found to offer superior fat suppression compared with conventional spectrally fat suppressed images.

  • 42.
    Berglund, Johan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.