TRADITIONAL POSTER - ismrm

Poster Sessions
Enrico Fermi Center,, Rome, Italy; 5 Department of Neurology, University of Rome “Sapienza”,, Rome, Italy; 6 Department of
Neurology, University of Rome “Sapienza”, Rome, Italy
In this study we applied two different methods to analyze fMRI data, acquired simultaneously with EEG, coming from experiments involving patients with
Idiopathic Generalized Epilepsy or with Cryptogenic Partial Epilepsy. We used first the data driven ICA (Independent Components Analysis) on fMRI data,
while in the second approach we applied the GLM (General Linear Model) on the same data, but exploiting the EEG recording to compute the regressor.
ICA and GLM analysis detected either activation areas located in agreement with presumed electroclinical hypothesis and the BOLD patterns of activation
in response to synchronized ictal activity.
2283. Comparison Between 2dTCA and EEG/fMRI to Localize Interictal Activity in Temporal Lobe
Epilepsy
Victoria L. Morgan 1 , Xiaoyun Liang 1 , John C. Gore 1 , Bassel Abou-Khalil 2
1 Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States; 2 Neurology, Vanderbilt University, Nashville, TN,
United States
Functional MRI (fMRI) has the potential for non-invasively localizing interictal epileptic activity more accurately than other clinical methods. Currently the
gold standard for detecting the timing of interictal activity during the fMRI scan is simultaneous electroencephalography (EEG). The objective of this work
is to compare a data-driven method, 2dTCA, to EEG/fMRI in temporal lobe epilepsy. Overall, there was good qualitative agreement between the two
methods with the 2dTCA maps showing more mesial temporal activation concurring with the presumed epileptogenic region in these patients, without the
need for the additional hardware, software, analyses and scalp EEG spikes required for EEG/fMRI.
2284. On the Advantage of Data Driven Analysis in Aphasic Patients with Severe Language Latency
Maria Engström 1 , Mattias Ragnehed 2 , Peter Lundberg 3
1 IMH/Radiological Sciences/CMIV, Linköping University, Linköping, Sweden; 2 IKE/Technical Audiology/CMIV, Linköping
University; 3 IMH/Radiation Physics/CMIV, Linköping University
Language fMRI in aphasic patients are exceptionally challenging. The patients often have latency in responding to cognitive tasks. Using a data-driven
approach for analysis might enable extraction of language networks even if the task is not performed at the intended pacing. In this study, five patients with
chronic aphasia were examined. Conventional analysis did not result in language activation in most patients. When using a data-driven approach, four out of
five patients elicited language related networks. It was concluded that language areas in patients with aphasia could be extracted using data driven analysis
even if the conventional fMRI analysis fails.
2285. Interictal Anomalies in Patients with Migraine Without Aura: Absence of Hemodynamic Refractory
Effects
Benedicte Descamps 1,2 , Pieter Vandemaele 1,2 , Harmen Reyngoudt 1,2 , Karel Deblaere 1,2 , Luc Leybaert 3 ,
Koen Paemeleire 3,4 , Eric Achten 1,2
1 Radiology, Ghent University, Ghent, Belgium; 2 GIfMI, Ghent, Belgium; 3 Basic Medical Sciences, Ghent University, Ghent,
Belgium; 4 Neurology, Ghent University Hospital, Ghent, Belgium
In this study, single subject net hemodynamic responses to paired stimuli from patients with migraine without aura and controls are fitted using inverse logit
functions and compared. We demonstrate that patients with migraine without aura do not show a decrease in amplitude of their interictal hemodynamic
response to a second stimulus in a pair with 1 second interstimulus interval, whereas the control group shows hemodynamic refractory effects when looking
at repetitive stimuli. The finding in this patient group may be the neurovascular correlate of the absence of electrophysiological habituation.
2286. Functional Connectivity After Fronto-Occipital Impact Mild Traumatic Brain Injury
Elena Shumskaya 1,2 , Teuntje Andriessen 2 , David Norris 1,3 , Pieter Vos 2
1 Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Gelderland, Netherlands;
2 Department of Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands; 3 Erwin L. Hahn
Institute for Magnetic Resonance, Essen, Germany
The objective of this study is to evaluate the alterations in the whole-brain functional connectivity after fronto-occipital impact mild traumatic brain injury
(MTBI). We used the resting state fMRI to relate the cognitive deficits occurring after frontal-occipital impact MTBI to the disruptions in functional
connectivity. We found the disintegration of prefrontal, temporal and parietal regions in resting-state networks of MTBI patients and showed that the
disconnection between prefrontal regions underlies the decline in the rate of information processing.
2287. fMRI Study of Response to Semantic Cueing During Verbal Learning in TBI
Rebecca Jo Chambers 1 , William M. Brooks 1 , JoAnn Lierman 1 , Laura E. Martin 1 , Amanda Bruce 1,2 , Brenda
A. Kirchhoff 3 , Monica Kurylo, Linda Ladesich, George Varghese, Cary R. Savage 1
1 Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, KS, United States; 2 University of Missouri -
Kansas City; 3 University of Missouri - St. Louis
Following TBI, memory functioning is frequently disrupted, and patients may not benefit from cognitive rehabilitation therapy. In an fMRI study,
participants’ responses were measured during a verbal learning task of semantically related or unrelated word lists. They were asked to first remember the
words with no further instruction, and then were cued to the semantic nature of the task. Both groups benefitted from semantic cueing, but showed
differential brain responses in left DLPFC, a region implicated in working memory. This finding may suggest that after TBI, patients must compensate with
additional neural processing in DLPFC to benefit from semantic cueing.