TRADITIONAL POSTER - ismrm

Poster Sessions
2299. Short-Long Functional Polymorphism of Serotonin Transporter Gene Modulates the Acute
Citalopram Challenge PhMRI Response
Darragh Downey 1 , Gabriella Juhasz 2 , Shane McKie 2 , Karen Elizabeth Davies 1 , Emma Jane Thomas 2 ,
Diana Chase 2 , Rebecca Elliott 2 , John Francis William Deakin 2 , Ian Muir Anderson 2 , Stephen Ross
Williams 1
1 Imaging Science and Biomedical Engineering, University of Manchester, Manchester, Lancashire, United Kingdom; 2 Neuroscience
and Psychiatry Unit, University of Manchester, Manchester, Lancashire, United Kingdom
We investigated whether citalopram-challenge phMRI, as a probe of serotonin transporter function, would detect functional variants of the serotonin
transporter gene and how this may influence normal serotonergic function. 42 normal volunteers underwent phMRI with intravenous 7.5mg citalopram.
Homozygous Short/Short allele carriers had reduced BOLD responses bilaterally in the caudate, mid-cingulate gyrus and parietal cortex and increases in the
superior frontal gyrus compared with the Long/Long carriers. The results offer the first direct evidence that the short and long variants of the 5HTT promoter
region indeed influence synaptic 5HT function in the living human brain.
2300. Occupational Solvent Exposure and Working Memory Function
David Matthew Carpenter 1 , Emily L. Eaves 1 , Cheuk Ying Tang 1 , Gudrun Lange 2,3 , Johnny Ng 4 , Nancy L.
Fiedler 5
1 Radiology, Mount Sinai School of Medicine, New York, United States; 2 Psychiatry, UMDNJ-New Jersey Medical School, Newark,
NJ; 3 Radiology, UMDNJ-New Jersey Medical School, West Orange, NJ, United States; 4 Radiology, City Colege ofl New York,
Bronx, NY, United States; 5 Environmental and Occupational Medicine, UMDNJ- Robert Wood Johnson Medical School, Piscataway,
NJ, United States
In this report BOLD fMRI to investigate the functional deficits of subjects with long-term occupational solvent exposure. Subjects underwent fMRI while
performing a Sternberg task and N-back working memory task. We used an exploratory voxel-wise and an ROI analysis to test the hypothesis that the
occupationally exposed subjects show hypo-activation in regions associated with working memory when compared to a carefully matched control group. the
results suggest that prolonged occupational solvent exposure is related to a decreased activation in regions associated with working memory.
2301. Can Resting State Measurements Supplement Task Based FMRI for Presurgical Motor Cortex
Mapping? a Test-Retest Reliability Study
Peter Mannfolk 1 , Markus Nilsson 1 , Ronnie Wirestam 1 , Freddy Ståhlberg 1,2 , Peter Fransson 3 , Andreas
Weibull 4 , Johan Olsrud 1,5
1 Dept. of Medical Radiation Physics, Lund University, Lund, Sweden; 2 Dept. of Diagnostic Radiology, Lund University Hospital,
Lund, Sweden; 3 Department of Clinical Neuroscience, Stockholm Brain Institute, Karolinska Institute, Stockholm, Sweden; 4 Dept. of
Medical Radiation Physics, Lund University, Malmö, Sweden; 5 Center for Medical Imaging and Physiology, Lund University
Hospital, Lund, Sweden
Clinical BOLD fMRI of children or in patients showing severe disease-related impairment can be difficult as active participation is required. Therefore, the
possibility of using resting state data would be of great value. The aim of this study was to evaluate the test-retest reliability in detecting the intrinsic motor
network from resting state data as compared to activation maps based on a bilateral finger tapping task. The test-retest reliability of resting state data was
found to be comparable to what is seen for a typical task based fMRI-experiment within a subject. However, large differences between subjects were also
found.
2302. Correcting for EPI Distortion at Very High Field Using the Fieldmap Method with Multi-Channel
Coils: Effectiveness in Presurgical Planning FMRI at 7 T
Simon Robinson 1 , Alexander Geissler 2 , Siegfried Trattnig 1 , Roland Beisteiner 2
1 High Field MR Centre, Department of Radiology, Medical University of Vienna, Vienna, Austria; 2 Clinical fMRI Study Group,
Departments of Neurology, Neurosurgery, and Radiology, Medical University of Vienna, Austria
We assess the effectiveness of a fast MGE sequence and postprocessing steps for fieldmapping with multichannel coils in correcting for EPI distortions in
presurgical planning fMRI at 7T. Complex conjugate phase combination, unwrapping, denoising and fieldmap thresholding (for maximum achievable
remapping) are described. Four patients underwent multiple runs of motor area localisation. Without distortion correction, primary foci for hand activation
were mislocalised by 5-7mm, which could give rise to serious postoperative impairment of function. No residual distortions were observed after distortion
correction, allowing fMRI results to be reliably registered to structural images and imported into neurosurgical planning systems.
2303. An Objective Approach to FMRI Assessment of Language Lateralization
David F. Abbott 1,2 , Anthony B. Waites 1,2 , Graeme D. Jackson 1,3
1 Brain Research Institute, Florey Neuroscience Institutes (Austin), Melbourne, Victoria, Australia; 2 Department of Medicine, The
University of Melbourne, Melbourne, Victoria, Australia; 3 Departments of Medicine & Radiology, The University of Melbourne,
Melbourne, Victoria, Australia
Language lateralization based on fMRI is often used in clinical neurological settings. With most conventional methods, the laterality determined can be
dependent on the quality of a particular study and chosen statistical threshold. We present an objective threshold-independent method of assessing when
individual patients have statistically atypical language lateralization. We illustrate the method using fMRI of verbal fluency in 34 healthy controls. One
could also apply the method to other paradigms or regional assessments; for example the assessment of lateralisation of a different task, or to the assessment
of anterior-posterior distribution rather than laterality.