Rebecca Emily Feldman¹, Jack Rutland², Bradley Neil Delman³, Jiyeoun Yoo⁴, Madeline Cara Fields⁴, Lara Vanessa Marcuse⁴, and Priti Balchandani^1
1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ²Wake Forest University, Winston-Salem, NC, United States, ³Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ⁴Neurology, Mount Sinai Hospital, New York, NY, United States

Epilepsy is a chronic condition, affecting approximately 150,000 people in the United States. 7T MRI facilitates the visualization of the brain with unprecedented resolution and contrast. Perivascular spaces (PVS) have been reported in previous work but with uncertain significance. However, due to the increased resolution enabled at 7T, PVSs are detected with increasing frequency, both in healthy volunteers and in epilepsy patients. We investigated the symmetry in the distribution of PVSs in the brains of non-lesional epilepsy patients. 

Graeme Jackson^1,2,3,4, Farnoosh Sadeghian¹, Patrick Carney¹, David Raffelt¹, Fernando Calamante^1,2, and Alan Connelly^1,2
1The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia, ²The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia, ³Department of Medicine, The University of Melbourne, Melbourne, Australia, ⁴Department of Neurology, Austin Health, Melbourne, Australia

Childhood absence epilepsy (CAE) is a common neurological condition. Here we assessed white matter connectivity using fixel-based analysis (FBA) and grey matter structure using voxel-based morphometry in adult patients with refractory CAE. We identified increased grey matter volume in frontal lobe as well as decreased fibre connectivity in superior longitudinal fasciculi, right cingulum, motor area of corpus callosum and cerebellar peduncles. Our results reinforce the concept that the midline frontal areas are critically involved in the phenotype of generalised spike and wave discharges. These structural connectivity changes in CAE could be either developmental or as a consequence of seizures.

Tim J Veersema¹, Cyrille H Ferrier¹, Pieter van Eijsden¹, Peter H Gosselaar¹, Fredy Visser^2,3, Jaco JM Zwanenburg^2,4, Hans Hoogduin², Gerárd AP de Kort², Jeroen Hendrike², and Kees PJ Braun^1
1Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, Netherlands, ²Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, ³Philips Healthcare, Best, Netherlands, ⁴Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands

For this series we assessed all 26 epilepsy patients who underwent 7T MRI for pre-surgical evaluation in our center, and whose scans (both 7T and lower field) were discussed during epilepsy surgery meetings (ESM). We compared the conclusions of the visual assessments of 1.5T or 3T, and 7T MRI as agreed upon by the ESM team. 7T MRI holds a promise to improve identification of epileptogenic structural abnormalities in patients with intractable epilepsy. In our series of 26 patients with refractory focal epilepsy, multidisciplinary evaluation of 7T MRI identified additional lesions not seen on lower-field MRI in five patients (19.2%).  

Xixi Zhao¹, Junling Wang¹, Xiangliang Tan¹, Xiang Xiao¹, Jiajun Zhang¹, Yingjie Mei², Queenie Chan³, and Yikai Xu^1
1Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou, China, People's Republic of, ²Philips Healthcare, Guangzhou, China, People's Republic of, ³Philips Healthcare, HongKong, China, People's Republic of

In human brain, T1ρ has been proven to be relevant with the macromolecular composition of tissues, and supposed to be sensitive to neuronal degeneration. We used T1rho MR imaging to investigate the variations in T1rho values of subcortical gray matter structures automatic-drawn using FIRST segmentation among temporal lobe epilepsy patients and the underlying relation between the significantly altered T1rho values or volumes of subcortical structures and duration of epilepsy or age at epilepsy onset. Our results demonstrate the feasibility of ROI-wise analysis by atlas-based segmentation of T1rho imaging among mTLE patients

Timothy Michael Shepherd¹, Yongxian Qian¹, Karthik Lakshmanan¹, Ruben Kuzniecky², Graham Wiggins¹, and Fernando Boada^1
1Radiology, New York University, New York, NY, United States, ²Neurology, New York University, New York, NY, United States

The detection and localization of sodium tissue abnormalities in patients with epilepsy may have potential to improve seizure localization, identify effective pharmacotherapy and/or provide prognostic information for individual patients. Here, we report initial results evaluating a newly developed coil for performing 23Na MRI at 3-T in three patients with epilepsy. 

Rebecca Emily Feldman¹, Bradley Neil Delman², Hadrien A Dyvorne¹, Jiyeoun Yoo³, Madeline Cara Fields³, Lara Vanessa Marcuse³, and Priti Balchandani^1
1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ²Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States,³Neurology, Mount Sinai Hospital, New York, NY, United States

Epilepsy affects over 150,000 people in the United States. Thirty percent of epilepsy is refractory to pharmacotherapy, and in these cases surgery may be curative. There are focal epileptogenic lesions, amenable to surgery, which are not visualized by current imaging protocols. 7T MRI scanners may increase the conspicuity of epileptogenic lesions and provide more accurate delineation of lesion boundaries. Reported are the results for a patient study, with comparison to healthy controls, to assess the value of 7T imaging to reveal subtle abnormalities acting as epileptogenic foci in patients with focal epilepsy who have non-lesional diagnostic MRI scans. 

Niels Leonard Schwaderlapp¹, Philipp Janz², Ute Häussler², Jan Korvink³, Dominik Elverfeldt¹, Jürgen Hennig¹, Carola Haas², and Pierre LeVan^1
1Medical Physics, University Medical Center Freiburg, Freiburg, Germany, ²Experimental Epilepsy Research, University Medical Center Freiburg, Freiburg, Germany, ³Institut für Mikrostrukturtechnik, Karlsruher Institut für Technologie, Karlsruhe, Germany

Cellular-level pathological changes in the kainate mouse model of temporal lobe epilepsy (TLE) have been well-characterized immunohistochemically (IHC) and include neuronal injury followed by granule cell dispersion. In this work, we demonstrate the possibility to non-invasively track granule cell dispersion and neuronal injury using diffusion imaging and ¹H-spectroscopy. The volume of the dispersed granule cell layer quantified by DTI and the initial injury reflected by a reduction of NAA and glutamate are quantitatively validated with IHC and can be used as early markers of epileptogenicity in this mouse model of TLE.

David Raffelt¹, Farnoosh Sadeghian¹, Brigid Regan², Sarah Garry², Samuel Berkovic², Ingrid Scheffer², and Alan Connelly^1,2
1Florey Institute of Neuroscience, Melbourne, Australia, ²Department of Medicine, University of Melbourne, Melbourne, Australia

Mutations in the gene DEPDC5 cause up to 12% of Familial Focal Epilepsy with Variable Foci. In this work we performed a fixel-based analysis of diffusion MRI data to understand how white matter might be altered in patients with DEPDC5 mediated frontal lobe epilepsy (FLE). We identified significant reductions in fibre density in several pathways, including the superior longitudinal fasciculi, corpus callosum, inferior longitudinal fasciculus and cingulum. We also investigated FLE mediated by KCNT1 mutation, and found similar pathways affected. In KCNT1+ve subjects, pathways had reduced cross-section, suggesting the observed effects may be related to development and not seizure effects. 

Russell Glenn¹, Leonardo Bonilha¹, Barbara Kreilkamp², Mark P Richardson³, Bernd Weber⁴, and Simon S Keller^2
1Medical University of South Carolina, Charleston, SC, United States, ²University of Liverpool, Liverpool, United Kingdom, ³King's College London, London, United Kingdom, ⁴University Hospital Bonn, Bonn, Germany

Imaging markers of postoperative seizure control in refractory temporal lobe epilepsy (TLE) would provide a useful clinical tool for surgical decision making. In the present diffusion tensor imaging study, we report that regional tissue characteristics of the fornix ipsilateral to the side of intended resection are related to postoperative seizure control in patients with TLE. Interestingly, areas found to be abnormal only in patients with a suboptimal outcome were located outside the margins of resection. The identification of fornical abnormalities outside the area of intended resection may be an important prognostic marker of suboptimal seizure control after temporal lobe surgery. 

Gerhard Drenthen^1,2, Marielle Vlooswijk^2,3, Marian Majoie², Paul Hofman^1,2, Albert Aldenkamp^2,3, Walter Backes^1,2, and Jacobus Jansen^1,2
1Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, Netherlands, ²School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands,³Department of Neurology, Maastricht University Medical Center, Maastricht, Netherlands

Brain network analysis that infers on interregional correlations of anatomical features usually makes use of intersubject correlation matrices that characterize variations over subjects. Here, a novel method is introduced that provides measures of network efficiency on an individual basis in patients with epilepsy. To this end, for each participant a measure of deviation from a group of healthy controls is calculated, and compared to the small-world parameters (clustering coefficient and minimum path length) of a reference graph obtained for the native control group. Results show that patients with epilepsy exhibit a less efficient network compared to controls.