Julia Pia Simon¹, Ben A. Duffy¹, Yan Li², Arthur W. Toga¹, Wolfgang G. Muhlhofer³, Robert C. Knowlton², and Hosung Kim^1
1University of Southern California, Los Angeles, CA, United States, ²Neurology and UCSF Weill Institute for Neurosciences, San Francisco, CA, United States, ³University of Alabama at Birmingham Epilepsy Center, Birmingham, AL, United States

Radiological MRI-negative temporal lobe epilepsy (TLE) is a common, but challenging subtype for surgical treatment. Compared to MRI-positive cases, these patients often require invasive EEG for localization that may also involve extratemporal regions. Furthermore, these cases entail a lower likelihood of seizure-free surgical outcome. To better understand this important group, we studied cortical surface features of MRI and FDG-PET to relate occult extratemporal damage to epilepsy localization and surgical outcome prediction. Bilateral cortical morphological changes were found. FDG-PET hypometabolism was lateralized in the hemisphere ipsilateral to seizure focus. Extratemporal and bilateral hypometabolism tended to be associated with poor surgical outcome.

Hui Huang¹, Miao Zhang², Rong Guo^3,4, Yudu Li^3,4, Yibo Zhao^3,4, Jialin Hu¹, Hongping Meng², Xinyun Huang², Xiaozhu Lin², Wei Liu⁵, Biao Li², Bomin Sun⁵, Yao Li¹, Zhi-Pei Liang^3,4, and Jie Luo^1
1Institute of Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China, ²Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China, ³Department of Electrical and Computer Engineering, University of Illinois at Urbana Champaign, Urbana, IL, United States, ⁴Beckman Institute for Advanced Sciences and Technology, University of Illinois at Urbana Champaign, Urbana, IL, United States, ⁵Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

PET and MRSI could provide metabolic information of the epileptogenic zone, which could add value to presurgical planning of epilepsy patients. This study investigated the feasibility of simultaneous high-resolution MRSI and ¹⁸F-FDG-PET for whole brain imaging in epilepsy patients, and studied the correlation between metabolic changes found in MRSI and hypometabolism found in FDG-PET. Our experimental results showed a decrease in NAA and an increase in Cho, concomitant with low FDG uptake.

Patrick Quarterman¹, Angela Lignelli², Marc Lebel³, and Sachin Jambawalikar^4
1GE Healthcare, New York, NY, United States, ²Radiology, Columbia University, New York, NY, United States, ³GE Healthcare, Calgary, AB, Canada, ⁴Columbia University, New York, NY, United States

The purpose of this study was to determine if deep learning reconstruction (DLRecon) method to reduce image noise could lead to improvement in in-vivo anatomical detail of the hippocampus structures without substantial increase in scan/exam time on a clinical 3T system. Evaluation of this new reconstruction technique was performed on a group of 5 volunteers with results indicating that higher resolution scans compared to current seizure protocol was free of imaging noise and led to higher confidence in identifying hippocampal key anatomical structures and temporal lobes.

Nicolò Rolandi¹, Fulvia Palesi¹, Francesco Padelli², Isabella Giachetti², Domenico Aquino², Giuseppe Didato³, Elio Maccagnano³, Paul Summers⁴, Giancarlo Germani⁴, Claudia AM Gandini Wheeler-Kingshott^1,5,6, and Paolo Vitali^4
1Department of Brain and Behavioral Science, University of Pavia, Pavia, Italy, ²Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta, Milan, Italy, ³Neuroradiology, Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta, Milan, Italy, ⁴Neuroradiology Unit, Brain MRI 3T Research Center, IRCCS Mondino Foundation, Pavia, Italy, ⁵Department of Neuroinflammation, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, NMR Research Unit, Queen Square MS Centre, London, United Kingdom, ⁶Brain MRI 3T Research Center, IRCCS Mondino Foundation, Pavia, Italy

Tract-based spatial statistics investigations of temporal lobe epilepsy (TLE) have been using standard diffusion metrics, without distinguishing patients according to the lateralization of their epileptogenic zone. The aim of this study is to further our knowledge by identifying specific patterns of alteration in left and right TLE patients using diffusion kurtosis imaging and NODDI parameter maps. Our findings demonstrate the presence of specific patterns of white matter alterations, with the left TLE more widely affecting both cerebral and cerebellar regions. These results support the need to consider patients separately, according to the side of their pathology.

Xiaozhi Cao^1,2,3, Kang Wang⁴, Congyu Liao^2,3, Dengchang Wu⁴, Qing Li¹, Ziyang Chen¹, Jun Li¹, Huihui Ye¹, Hongjian He¹, and Jianhui Zhong^1
1Center for Brain Imaging Science and Technology, Department of Biomedical Engineering, Zhejiang University, Hangzhou, China, ²Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, charlestown, MA, United States, ³Department of Radiology, Harvard Medical School, charlestown, MA, United States, ⁴Department of Neurology, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China

We propose to use a 3D MRF technique with multi-axis spiral projection acquisition to achieve 3D high-resolution whole-brain quantitative imaging for patients with MTLE. Isotropic 1-mm resolution relaxivity maps were achieved within 5 minutes. By incorporating Freesurfer’s automatic subcortical segmentation, a whole-brain subcortical segmentation was obtained, enabling feasible and subjective quantitative analysis for each substructure. Additionally, volume information of the substructure was obtained during the process.

Karthik Kulanthaivelu¹, Kiran Raj V¹, Raghavendra Kenchaiah ², Jitender Saini¹, Rose Dawn Bharath¹, and Sanjib Sinha^2
1Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and Neurosciences, Bengaluru, India, ²Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, India

“Focal” epilepsy is a network aberration. Network characteristics in focal epilepsy due to calcified Neurocysticercal granuloma have not been elucidated. Forty-two patients of focal epilepsy with MRI evidence of either calcified granuloma, malformation of cortical development, mesial temporal sclerosis, or no imaging abnormality were included. Group-level Cortical thickness covariance networks were generated and compared. Focal epilepsy patients (including those with calcific granuloma) had significantly reduced network global efficiency and higher nodal characteristic path length/ Clustering coefficient/ Nodal local efficiency (p<0.05). Networks in focal epilepsy (“ including those due to calcific granuloma”) have higher segregation and lesser integration. 

Yae Won Park¹, Dongmin Choi², Kyunghwa Han¹, Sung Soo Ahn¹, Hwiyoung Kim¹, and Hyang Woon Lee^3
1Yonsei University College of Medicine, Seoul, Republic of Korea, ²Department of Computer Science, Yonsei University, Seoul, Republic of Korea, ³Department of Neurology, Ewha Womans University College of Medicine, Seoul, Republic of Korea

A total of 92 subjects(66 TLE [35 right and 31 left] and 26 healthy controls) were allocated to training(n=66) and test(n=26) sets. Radiomics features (n=558) from the bilateral hippocampi were extracted from T1WI and DTI. Machine learning models were trained. Identical processes were performed to differentiate right TLE from HC and left TLE from HC. The radiomics model in test set showed better performance than hippocampal volume for identifying TLE (AUC 0.82 vs. AUC 0.62, P=0.08). Radiomics models of both subgroups showed better performance than those of hippocampal volume(AUC 0.76 vs. AUC 0.54 [P=0.12] and AUC 0.95 vs 0.68 [P=0.04]).

Joon Yul Choi¹, Rasim Boyacioglu², Stephen Jones³, Ken Sakaie³, Ingmar Blümcke^1,4, Imad Najm¹, Mark Griswold², Dan Ma⁵, and Zhong Irene Wang^1
1Epilepsy Center / Neurological Institute, Cleveland Clinic, Cleveland, OH, United States, ²Radiology, Case Western Reserve University, Cleveland, OH, United States, ³Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, ⁴Neuropathology, University of Erlangen, Erlangen, Germany, ⁵Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States

We investigate in this study quantitative T1 and T2 values as potential biomarkers of tissue properties in epilepsy patients with focal cortical dysplasia (FCD) using a novel high-resolution 3D magnetic resonance fingerprinting (MRF) technique. We first investigated the quantitative T1 and T2 values in various Brodmann areas to verify the sensitivity of MRF in probing tissue properties of the human cortex. We then investigated the MRF T1 and T2 values in different subtypes of FCD lesions, which were higher than their corresponding cortical regions in the controls.

Xinyu Hu¹, Wenyu Liu², Dong Zhou², Qiyong Gong¹, and Xiaoqi Huang^1
1Huaxi MR Research Center (HMRRC), West China Hospital of Sichuan University, Chengdu, China, ²Department of Neurology, West China Hospital of Sichuan University, Chengdu, China

We performed the first resting-state fMRI study integrating both whole-brain functional connectivity (FC) and seed-based FC analyses to explore the network-level neural function alterations in patients with periventricular nodular heterotopia (PNH). Our findings (i) identified lower functional connectivity strength (FCS, an index of whole-brain connectivity) in bilateral insula, higher FC in the precuneus and lower FC in the anterior cingulate cortex/medial prefrontal cortex and cerebellum networks in PNH patients and (ii) demonstrated that the significant insular hypoactivation represented the cortical hub of the whole-brain networks in PNH, which might be of clinical significance in predicting disability progression of PNH.

Lawrence Ver Hoef^1,2, Mike Zhang³, and Anandh Kilpattu Ramaniharan^3
1Neurology, University of Alabama at Birmingham, Birmingham, AL, United States, ²Birmingham VA Medical Center, Birmingham, AL, United States, ³University of Alabama at Birmingham, Birmingham, AL, United States

Hippocampal dentation (HD) is a morphologic feature of the human hippocampus that has been recently described and has been shown to correlate with aspects of verbal and visual memory. It varies dramatically across healthy individuals and can be affected by diseases such as epilepsy. We demonstrate a method to extract ultra-high-resolution surface contours from common MPRAGE images. We also propose a method based on absolute mean curvature to quantify HD and compare that to visual inspection in a cohort of temporal lobe epilepsy patients. Finally, we examine correlations between HD and measures of verbal and visual memory across methods.

Sara Lorio¹, Po-Wah So¹, Jan Sedlacik¹, Derek Li², Emma Dixon³, Sophie Adler³, Harold G. Parkers¹, Helen J. Cross³, Torsten Baldeweg³, Thomas Jacques³, Karin Shmueli³, and David Carmichael^1,3
1King's College London, London, United Kingdom, ²UCL, London, United Kingdom, ³UCL, LONDON, United Kingdom

We estimated quantitative susceptibility maps (QSM) in 19 children with histologically confirmed focal cortical dysplasia (FCD), a frequent cause of drug-resistant epilepsy. QSM allowed measurement of cortical and sub-cortical layered structure and its alteration in FCD lesions. Moreover, QSM was sensitive to abnormal deposits of calcium, zinc, and iron, which were validated using X-ray fluorescence in brain tissue specimens available following surgical treatment. QSM could provide a non-invasive biomarker of cortical tissue changes in epilepsy and could be used to determine alterations in mineral deposits in different brain disorders.

Boyu Zhang¹, Shaoping Zhong², Yuwen Zhang¹, Qianfeng Wang¹, Jing Ding², and He Wang^1,3
1Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China, ²Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China, ³Human Phenome Institute, Fudan University, Shanghai, China

Focal cortical dysplasia (FCD) are neurodevelopmental disorders characterized by localized cortical malformation that is highly associated with the drug-resistant epilepsy. In this study, we examined the advanced diffusion MR imaging-neurite orientation dispersion and density imaging (NODDI) in the FCD mice model. The orientation dispersion index (ODI) that represents the dispersion of neurite is significantly higher in the FCD group compared with the control group which are compatible with the pathological observation. Meanwhile, no significant differences are observed in conventional DTI measurements FA and MD indicating that NODDI is more sensitive in detecting FCD lesion.

Nian Yu^1,2,3, Benjamin Sinclair^4,5, Lina Maria Garcia Posada⁶, Ben Chen⁴, Qing Di¹, Xingjian Lin¹, Qingling Huang⁷, Scott Kolbe⁴, Patrick Kwan^2,4,5,8, and Meng Law^4,6
1Department of Neurology, The Nanjing Brain Hospital Affiliated to Nanjing Medical University, Nanjing, China, ²Department of Neurology, Royal Melbourne Hospital, Melbourne, Australia, ³Department of Radiology, The Nanjing Brain Hospital Affiliated to Nanjing Medical University, Melbourne, China, ⁴Department of Neuroscience, Monash University, Melbourne, Australia, ⁵Department of Neurology, Alfred Hospital, Melbourne, Australia, ⁶Department of Radiology, Alfred Hospital, Melbourne, Australia, ⁷Department of Radiology, The Nanjing Brain Hospital Affiliated to Nanjing Medical University, Nanjing, China, ⁸Department of Medicine, University of Melbourne, Melbourne, Australia

Around 10% of patients with stroke go on to develop epilepsy, however, imaging biomarkers for post-stroke epilepsy (PSE) are lacking. Perivascular spaces (PVS) are small interstitial fluid filled spaces lining the blood vessels which have a role in waste clearance in the brain. They have been found to be abnormal in epilepsy, and here we investigate whether they could serve as an early predictor of PSE. We found that the overall number and scores of enlarged PVSs were not associated with PSE, but the inter-hemispheric asymmetry was an independently associated biomarker.