Trondheim, Norway
Trondheim, Norway

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Amundsen T.,St Olavs Hospital Hf | Amundsen T.,Norwegian University of Science and Technology | Sundstrom S.,St Olavs Hospital Hf | Gederaas O.A.,Norwegian University of Science and Technology | Haaverstad R.,University of Bergen
Acta Oncologica | Year: 2014

Background. On the basis of our own experience and literature search, we hypothesised that a canine olfactory test may be useful for detecting lung cancer in an unselected population of patients suspected to have lung cancer. Material and methods. We conducted a prospective study of 93 patients consecutively admitted to hospital with suspected lung cancer. Exhaled breath and urine were sampled before the patients underwent bronchoscopy. The canine olfactory test was performed in a double-blinded manner. Sensitivity and specificity were outcome measures. Results. With 99% sensitivity, the olfactory test demonstrated that dogs have the ability to distinguish cancer patients from healthy individuals. With an intensified training procedure, the exhaled breath and urine tests showed sensitivity rates of 56-76% and specificity rates of 8.3-33.3%, respectively, in our heterogeneous study population. Conclusion. Although the olfactory test appears to be a promising tool for the detection of cancer, the main challenge is to determine whether the test can sufficiently discriminate between patients at risk, patients with benign disease, and patients with malignant disease. We need to gain a deeper understanding of this test and further refine it before applying it as a screening tool for lung cancer in clinical settings. © 2014 Informa Healthcare.

Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2011-1.1.5. | Award Amount: 10.83M | Year: 2012

ECRIN is a distributed ESFRI-roadmap pan-European infrastructure designed to support multinational clinical research, making Europe a single area for clinical studies, taking advantage of its population size to access patients. Servicing multinational trials started during its preparatory phase, and it now applies for an ERIC status by 2011. The ERIC budget will be restricted to core activities required to enable provision of services, and the ECRIN-IA project is designed to expand ECRIN partnerships and impact beyond this core activity. Networking activities will promote pan-European expansion, capacity building, and partnership with other world regions, and address the funding issue (WP2). ECRIN-IA will develop e-services, education material to train professionals and patients associations, and communication with users, patients, citizens and policymakers (WP3). It will support the structuring and connection to ECRIN of disease-, technology-, or product-oriented investigation networks and hubs focusing on specific areas: rare diseases (WP4), medical device (WP5), nutrition (WP6). Transnational access activities will support the cost of multinational extension of clinical trials on rare diseases, medical device and nutrition selected by the ECRIN scientific board (WP7). Joint research activities are designed to improve the efficiency of ECRIN services, through the development of tools for risk-adapted monitoring (WP8), and the upgrade of the VISTA data management tool (WP9). This project will build a consistent organisation for clinical research in Europe, with ECRIN developing generic tools and providing generic services to multinational studies, and supporting the construction of pan-European disease-oriented networks, that will in turn act as ECRIN users and provide the scientific content. Such organisation will improve Europes attractiveness for industry trials, boost its scientific competitiveness, and result in better healthcare for European citizens.

Agency: Cordis | Branch: FP7 | Program: MC-ITN | Phase: FP7-PEOPLE-ITN-2008 | Award Amount: 3.71M | Year: 2009

The scope of the present consortium is to provide technology and training for the integration of ultrasound and biophotonics based imaging with magnetic resonance imaging (MRI), Computed Tomography (CT) and Positron Emission Tomography (PET) to define the specs of an Integrated Interventional Imaging Operating System (III OS) aimed at minimal invasive treatment of common life-threatening disorders, e.g., cancer, cardiovascular disease and structural heart defects. Effective therapy of these conditions will require a range of safe surgical and interventional devices used with the necessary visualization and tracking under real-time image guidance. The consortium includes a critical mass of industrial and university research institute partners with high expertise in design, development, and manufacture of these devices and instruments. To ensure medical the safety and economical usability of the system and to allow an optimal integration into the future hospital workflow, 6 university hospitals will contribute their clinical and administrative expertise to the consortium in the fields of Interventional Radiology/Cardiology, Anaesthesia, Oncology, General and Cardiovascular Surgery and preclinical Image guided procedures. The consortium of the IIIOS research and training process includes two Biomedical Technology Societies: DGBMT and SMIT&MEDIS Foundation in Rumania providing expert networking and conference organization. The is involved in the consortium and will play a key role in the exchange of knowledge and expertise to the new member states of the EU through hosting conferences such SMIT 2009 in Sinaia (

Severino M.,G Gaslini Childrens Hospital | Schwartz E.S.,Children's Hospital of Philadelphia | Thurnher M.M.,Medical University of Vienna | Rydland J.,St Olavs Hospital Hf | And 2 more authors.
Neuroradiology | Year: 2010

Congenital tumors of the central nervous system (CNS) are often arbitrarily divided into "definitely congenital" (present or producing symptoms at birth), "probably congenital" (present or producing symptoms within the first week of life), and "possibly congenital" (present or producing symptoms within the first 6 months of life). They represent less than 2% of all childhood brain tumors. The clinical features of newborns include an enlarged head circumference, associated hydrocephalus, and asymmetric skull growth. At birth, a large head or a tense fontanel is the presenting sign in up to 85% of patients. Neurological symptoms as initial symptoms are comparatively rare. The prenatal diagnosis of congenital CNS tumors, while based on ultrasonography, has significantly benefited from the introduction of prenatal magnetic resonance imaging studies. Teratomas constitute about one third to one half of these tumors and are the most common neonatal brain tumor. They are often immature because of primitive neural elements and, rarely, a component of mixed malignant germ cell tumors. Other tumors include astrocytomas, choroid plexus papilloma, primitive neuroectodermal tumors, atypical teratoid/rhabdoid tumors, and medulloblastomas. Less common histologies include craniopharyngiomas and ependymomas. There is a strong predilection for supratentorial locations, different from tumors of infants and children. Differential diagnoses include spontaneous intracranial hemorrhage that can occur in the presence of coagulation factor deficiency or underlying vascular malformations, and congenital brain malformations, especially giant heterotopia. The prognosis for patients with congenital tumors is generally poor, usually because of the massive size of the tumor. However, tumors can be resected successfully if they are small and favorably located. The most favorable outcomes are achieved with choroid plexus tumors, where aggressive surgical treatment leads to disease-free survival. © 2010 Springer-Verlag.

Brekke E.,Norwegian University of Science and Technology | Brekke E.,Nordland Hospital Trust | Morken T.S.,Norwegian University of Science and Technology | Morken T.S.,St Olavs Hospital Hf | Sonnewald U.,Norwegian University of Science and Technology
Neurochemistry International | Year: 2015

Glucose is essentially the sole fuel for the adult brain and the mapping of its metabolism has been extensive in the adult but not in the neonatal brain, which is believed to rely mainly on ketone bodies for energy supply. However, glucose is absolutely indispensable for normal development and recent studies have shed light on glycolysis, the pentose phosphate pathway and metabolic interactions between astrocytes and neurons in the 7-day-old rat brain. Appropriately 13C labeled glucose was used to distinguish between glycolysis and the pentose phosphate pathway during development. Experiments using 13C labeled acetate provided insight into the GABA-glutamate-glutamine cycle between astrocytes and neurons. It could be shown that in the neonatal brain the part of this cycle that transfers glutamine from astrocytes to neurons is operating efficiently while, in contrast, little glutamate is shuttled from neurons to astrocytes. This lack of glutamate for glutamine synthesis is compensated for by anaplerosis via increased pyruvate carboxylation relative to that in the adult brain. Furthermore, compared to adults, relatively more glucose is prioritized to the pentose phosphate pathway than glycolysis and pyruvate dehydrogenase activity. The reported developmental differences in glucose metabolism and neurotransmitter synthesis may determine the ability of the brain at various ages to resist excitotoxic insults such as hypoxia-ischemia. © 2015 Elsevier Ltd. All rights reserved.

Wichstrom L.,Norwegian University of Science and Technology | Wichstrom L.,St Olavs Hospital Hf | Berg-Nielsen T.S.,Norwegian University of Science and Technology | Angold A.,Duke University | And 3 more authors.
Journal of Child Psychology and Psychiatry and Allied Disciplines | Year: 2012

Background: Many disorders in childhood and adolescence were already present in the preschool years. However, there is little empirical research on the prevalence of psychiatric disorders in young children. A true community study using structured diagnostic tools has yet to be published. Methods: All children born in 2003 or 2004 in the city of Trondheim, Norway, who attended the regular community health check-up for 4-year-olds (97.2% of eligible children) whose parents consented to take part in the study (N = 2,475, 82.0%) were screened for behavioral and emotional problems with the Strengths and Difficulties Questionnaire (SDQ). A screen-stratified subsample of 1,250 children took part in a furthermore comprehensive study including a structured diagnostic interview (the Preschool Age Psychiatric Assessment, PAPA), which 995 parents (79.6%) completed. Results: The estimated population rate for any psychiatric disorder (excluding encopresis - 6.4%) was 7.1%. The most common disorders were attention deficit hyperactivity disorder (1.9%), oppositional defiant disorder (1.8%), conduct disorder (0.7%), anxiety disorders (1.5%), and depressive disorders (2.0%). Comorbidity among disorders was common. More emotional and behavioral disorders were seen in children whose parents did not live together and in those of low socioeconomic status. Boys more often had attention-deficit/hyperactivity disorder (ADHD) and depressive disorders than girls. Conclusions: The prevalence of disorders among preschoolers was lower than in previous studies from the USA. Comorbidity was frequent and there was a male preponderance in ADHD and depression at this early age. These results underscore the fact that the most common disorders of childhood can already be diagnosed in preschoolers. However, rates of disorder in Norway may be lower than in the USA. © 2011 The Authors. Journal of Child Psychology and Psychiatry.

Kristoffersen A.,St Olavs Hospital Hf
Journal of Magnetic Resonance Imaging | Year: 2012

Purpose: To assess the effects of Rician bias and physiological noise on parameter estimation for non-Gaussian diffusion models. Materials and Methods: At high b-values, there are deviations from monoexponential signal decay known as non-Gaussian diffusion. Magnitude images have a Rician distribution, which introduces a bias that appears as non-Gaussian diffusion. A second factor that complicates parameter estimation is physiological noise. It has an intensity that depends on the b-value in a complicated manner. Hence, the signal distribution is unknown a priori. By measuring a large number of averages, however, the variance at each b-value can be estimated. Using Monte Carlo simulations, we compared uncorrected estimation to a corrected scheme that involves fitting to the mean value of the Rician distribution. We also evaluated effects of weighting with the inverse of the estimated variance in least-squares fitting. A human brain experiment illustrates parameter estimation effects and identifies brain regions affected by physiological noise. Results: The simulations show that the corrected estimator is very accurate. The uncorrected estimator is heavily biased. In the human brain experiment, the magnitude of the relative bias ranges from 6%-31%, depending on the diffusion model. Weighting has negligible effects on accuracy, but improves precision in the presence of physiological noise. At low b-values, physiological noise is prominent in cerebrospinal fluid. At high b-values there is physiological noise in white matter structures near the ventricles. Conclusion: Bias correction is essential and weighting may be beneficial. Physiological noise has significant effects. © 2011 Wiley Periodicals, Inc.

Kristoffersen A.,St Olavs Hospital Hf
Magnetic Resonance in Medicine | Year: 2011

In human brain diffusion measurements, there are deviations from monoexponential signal decay at high values of the diffusion-weighting factor b. This is known as non-Gaussian diffusion and can provide novel kinds of image contrast. We evaluated quantitatively the goodness-of-fit of five popular diffusion models. Because of the Rician signal distribution and physiological noise, the measurement errors are unknown. This precludes standard π 2 testing. By repeating the measurement 25 times, the errors were estimated. Hypothesis testing based on the residual after least squares curve fitting was then carried out. Systematic errors originating from the Rician signal bias were eliminated in the fitting procedure. We performed diffusion measurements on four healthy volunteers with b-values ranging from 0 to 5000 s/mm 2. The data were analyzed voxelwise. The null hypothesis of a given model being adequate was rejected, if the residual after fitting exceeded a limit that corresponds to a significance level of 1%. The fraction of rejected voxels depended strongly on the number of free model parameters. The rejected fraction was: monoexponential model with two parameters, 94%; statistical model with three parameters, 29%; stretched exponential model with three parameters, 35%; cumulant model with three parameters, 48%; cumulant model with four parameters, 11%; biexponential model with four parameters, 2.9%. Copyright © 2011 Wiley Periodicals, Inc.

Kristoffersen A.,St Olavs Hospital Hf
Journal of Magnetic Resonance Imaging | Year: 2013

Purpose: To test the performance of three existing models of diffusional non-Gaussianity and introduce a new model. Materials and Methods: Quantitative measures of diffusional non-Gaussianity provide clinically useful information. Three-parameter mathematical models are particularly relevant, because they assign one parameter to non-Gaussianity, one to diffusivity and one to the signal in the absence of diffusion weighting. One such model is the cumulant expansion, where the logarithm of the signal is approximated by a Taylor series. Convergence may be blocked by singularities in the complex b-plane. To overcome this problem, we replace the Taylor series by a Padé approximant, which can model singularities. The resulting signal model is denoted the Padé exponent model. Analyzing diffusion-weighted brain data from four volunteers, we compare the performance of the Padé exponent model with the statistical model, the stretched exponential model and the cumulant expansion. With voxelwise hypothesis testing, we calculate the fraction of voxels where the models fail to describe the data. Results: With 16 b-values in the range [0,5000] s/mm2, the fractions of rejected voxels in white / gray matter are: statistical model, 41 / 20%; stretched exponential model, 68 / 16.6%; cumulant expansion, 58 / 37%; Padé exponent, 5.2 / 16.1%. The parameters of the Padé exponent model do not depend strongly on the range of measured b-values. Conclusion: The Padé exponent model describes non-Gaussian diffusion data with high precision over a wide range of b-values. © 2013 Wiley Periodicals, Inc.

Kristoffersen A.,St Olavs Hospital Hf | Goa P.E.,St Olavs Hospital Hf
Journal of Magnetic Resonance | Year: 2011

The physiological noise in 3D image acquisition is shown to depend strongly on the sampling scheme. Five sampling schemes are considered: Linear, Centric, Segmented, Random and Tuned. Tuned acquisition means that data acquisition at k-space positions k and -k are separated with a specific time interval. We model physiological noise as a periodic temporal oscillation with arbitrary spatial amplitude in the physical object and develop a general framework to describe how this is rendered in the reconstructed image. Reconstructed noise can be decomposed in one component that is in phase with the signal (parallel) and one that is 90° out of phase (orthogonal). Only the former has a significant influence on the magnitude of the signal. The study focuses on fMRI using 3D EPI. Each k-space plane is acquired in a single shot in a time much shorter than the period of the physiological noise. The above mentioned sampling schemes are applied in the slow k-space direction and noise propagates almost exclusively in this direction. The problem then, is effectively one-dimensional. Numerical simulations and analytical expressions are presented. 3D noise measurements and 2D measurements with high temporal resolution are conducted. The measurements are performed under breath-hold to isolate the effect of cardiac-induced pulsatile motion. We compare the time-course stability of the sampling schemes and the extent to which noise propagates from a localized source into other parts of the imaging volume. Tuned and Linear acquisitions perform better than Centric, Segmented and Random. © 2011 Elsevier Inc. All rights reserved.

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