Projects at the Danish Research Centre for Magnetic Resonance

Transcription

1 Projects at the Danish Research Centre for Magnetic Resonance Five projects involving Magnetic Resonance Imaging (MRI) Hvidovre Hospital

2 Magnetic Resonance Imaging, MRI Magnetic Resonance Imaging Nuclei in body are aligned so the patient becomes magnetic. Radiowaves are used to make the magnetic needle swing. Radiowave signals from oscillating dipoles are detected.

3 MR projects Interdisciplinarity: Supervisors are MDs, psychologist, biologists, engineers and physicists. The following 5 projects are described in detail at MSc-project: Hippocampal shape differences in subjects at risk to develop depression. Supervisors:Arnold Skimminge, Rasmus Larsen (DTUIMM), William Baaré BSc/MSc-project: Measurement of the magnetization of Carbon13 used for MRI Supervisors: Lise Vejby Søgaard, Peter Magnusson, Lars G. Hanson (DTU), Erik Sjøntoft (DTU, foreslået)

4 MR projects MSc-project: Mapping changes in brain activation patterns in individuals at risk for depression Supervisors: Julian Macoveanu, Hartwig Siebner, Lars Kessing (RH) MSc/BSc-project: EEG measured during MRI - Phantombased evaluation of algorithms for removal of scanner induced EEG noise Supervisors: Lars G. Hanson (DTU), Kristoffer Madsen, Christian G. Hanson MSc/BSc-project: Infusion pump for MRI Supervisors: Jan Henrik Ardenkjær-Larsen (GE), Lise V. Søgaard, Peter Magnusson, Lars G. Hanson (DTU)

5 Hippocampal shape differences in subjects at risk to develop depression Subject sample Hippocampal subfields mapped onto the hippocampal surface Ballmaier et al, Am J Psychiatry 2008 Arnold Skimminge, Msc (DRCMR, Hvidovre Hospital); drcmr.dk; William Baaré, PhD (DRCMR, Cimbi, Hvidovre Hospital); drcmr.dk Prof. Rasmus Larsen (DTU); imm.dtu.dk

6 BSc/MSc-project: Using MR-scanning to image macro-molecules in the brain. New method established: Carbon13-hyperpolarization (magnetic nuclear labelling) Example: Pyruvate signal enhanced by approximately a factor 10000! Substance is cooled, magnetized, heated, injected and metabolization is imaged in scanner. Project: Measurement of the magnetization of hyperpolarized Carbon13 used for MRI. Interfacing of detection coil with scanner, and design measurement to determine magnetization of injected Copenhagen University Hospital, Hvidovre substancedrcmr, simultaneously with MR acquisition.

7 Spectral time series acquired during i.v. injection of hyperpolarized 1-13Cpyruvate in mouse The spectral time series plot shows the build-up of injected pyruvate during the first 10 s, the following delayed build-up of the lactate- and alaninemetabolites, and signal decay due to relaxation. The data reflects the dynamics of the metabolism in the studied region and is useful for optimizing the timing of rapid spectroscopic imaging Project: Infusionpump for MRI. Construct and of injected hyperpolarized implement an infusion pump for reproducible and fast delivery of hyperpolarized1-13c-puruvate. substances from the hyperpolarizer to the animal.

8 EEG-MRI: Phantom-based evaluation of algorithms for removal of scanner induced EEG noise EEG-fMRI aim: EEG answers when?, fmri answers where? EEG corrupted by MRI Noise from field changes and pulse Artifact removal can be done, but there are reasons to be suspicious, and the result is difficult to verify. Unique EEG signal generator and artificial head was constructed to compare methods properly. Be the first to try. Project with hands-on scanning and data analysis. Lars G. Hanson (DTU/DRCMR); drcmr.dk; Kristoffer Madsen, PhD (DTU-IMM/DRCMR); drcmr.dk, Christian G. Hanson

9 Serotonin (5-Hydroxytryptamin) a key player in regulating emotions 5HT plays an important role as a neurotransmitter in the modulation of anger, aggression, mood, sleep, sexuality, appetite, body temperature

10 Altered brain activity in individuals at risk for depression: Serotonin re-uptake inhibitor normalizes latent dysfunction SSRI or Placebo (4weeks) 1st fmri session 2nd fmri session Healthy subjects with increased familial risk Julian Macoveanu, PhD. MSc drcmr.dk); Tel Prof. Hartwig Siebner, MD drcmr.dk); Bettina Hornbøll, MSc drcmr.dk) Prof. Lars Kessing (MD, DMSc, Department of Psychiatry, Rigshospitalet)

11 How do acute changes in the serotonergic system modify the functional cross-talk within functional brain networks? Reduced serotonergic tone - Acute Tryptophan Depletion - Blockade of 5-HT2A (Ketanserin) Increased serotonergic tone - Selective Serotonin Re-uptake Inhibitor (SSRI) Angry Julian Macoveanu, PhD, MSc, drcmr.dk; Tel Prof. Hartwig Siebner, MD (hartwig.siebner@drcmr.dk); Bettina Hornbøll, MSc (bettinah@drcmr.dk) Prof. Gitte Moos Knudsen, MD, PhD (CIMBI, NRU, Rigshospitalet)

12 Additional information The five projects are described in detail at Contact the supervisors or Lars G. Hanson, (wednesdays and thursdays) to learn more about projects at the DRCMR. See also