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Pinto SN, Lerner A, Phung D, Barisano G, Chou B, Xu W, Sheikh-Bahaei N. Arterial Spin Labeling in Migraine: A Review of Migraine Categories and Mimics. J Cent Nerv Syst Dis 2023. [DOI: 10.1177/11795735231160032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
Migraine is a complex headache characterized by changes in functional connectivity and cerebral perfusion. The perfusion changes represent a valuable domain for targeted drug therapy. Arterial spin labeling is a noncontrast imaging technique of quantifying cerebral perfusion changes in the migraine setting. In this narrative review, we will discuss the pathophysiology of the different categories of migraine, as defined by the International Classification of Headache Disorders-3 and describe a category-based approach to delineating perfusion changes in migraine on arterial spin labeling images. We will also discuss the use of arterial spin labeling to differentiate migraine from stroke and/or seizures in the adult and pediatric populations. Our systematic approach will help improve the understanding of the complicated vascular changes that occur during migraines and identify potential areas of future research.
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Affiliation(s)
- Soniya N Pinto
- Department of Diagnostic Imaging, St Jude Children’s Research Hospital, Memphis, TN, USA
| | - Alexander Lerner
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
| | - Daniel Phung
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
| | - Giuseppe Barisano
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
| | - Brendon Chou
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
| | - Wilson Xu
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
| | - Nasim Sheikh-Bahaei
- University of Southern California, Keck School of Medicine, Los Angeles, CA, USA
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Yao L, Cheng N, Chen AQ, Wang X, Gao M, Kong QX, Kong Y. Advances in Neuroimaging and Multiple Post-Processing Techniques for Epileptogenic Zone Detection of Drug-Resistant Epilepsy. J Magn Reson Imaging 2023. [PMID: 38014782 DOI: 10.1002/jmri.29157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/29/2023] Open
Abstract
Among the approximately 20 million patients with drug-resistant epilepsy (DRE) worldwide, the vast majority can benefit from surgery to minimize seizure reduction and neurological impairment. Precise preoperative localization of epileptogenic zone (EZ) and complete resection of the lesions can influence the postoperative prognosis. However, precise localization of EZ is difficult, and the structural and functional alterations in the brain caused by DRE vary by etiology. Neuroimaging has emerged as an approach to identify the seizure-inducing structural and functional changes in the brain, and magnetic resonance imaging (MRI) and positron emission tomography (PET) have become routine noninvasive imaging tools for preoperative evaluation of DRE in many epilepsy treatment centers. Multimodal neuroimaging offers unique advantages in detecting EZ, especially in improving the detection rate of patients with negative MRI or PET findings. This approach can characterize the brain imaging characteristics of patients with DRE caused by different etiologies, serving as a bridge between clinical and pathological findings and providing a basis for individualized clinical treatment plans. In addition to the integration of multimodal imaging modalities and the development of special scanning sequences and image post-processing techniques for early and precise localization of EZ, the application of deep machine learning for extracting image features and deep learning-based artificial intelligence have gradually improved diagnostic efficiency and accuracy. These improvements can provide clinical assistance for precisely outlining the scope of EZ and indicating the relationship between EZ and functional brain areas, thereby enabling standardized and precise surgery and ensuring good prognosis. However, most existing studies have limitations imposed by factors such as their small sample sizes or hypothesis-based study designs. Therefore, we believe that the application of neuroimaging and post-processing techniques in DRE requires further development and that more efficient and accurate imaging techniques are urgently needed in clinical practice. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Lei Yao
- Clinical Medical College, Jining Medical University, Jining, China
| | - Nan Cheng
- Medical Imaging Department, Affiliated Hospital of Jining Medical University, Jining, China
| | - An-Qiang Chen
- Medical Imaging Department, Affiliated Hospital of Jining Medical University, Jining, China
| | - Xun Wang
- Medical Imaging Department, Affiliated Hospital of Jining Medical University, Jining, China
| | - Ming Gao
- Medical Imaging Department, Affiliated Hospital of Jining Medical University, Jining, China
| | - Qing-Xia Kong
- Department of Neurology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Yu Kong
- Medical Imaging Department, Affiliated Hospital of Jining Medical University, Jining, China
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Rentzeperis F, Abdennadher M, Snyder K, Dembny K, Abdollahi S, Zaghloul KA, Talagala L, Theodore WH, Inati SK. Lateralization of interictal temporal lobe hypoperfusion in lesional and non-lesional temporal lobe epilepsy using arterial spin labeling MRI. Epilepsy Res 2023; 193:107163. [PMID: 37187039 PMCID: PMC10247543 DOI: 10.1016/j.eplepsyres.2023.107163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 04/11/2023] [Accepted: 05/01/2023] [Indexed: 05/17/2023]
Abstract
PURPOSE Non-invasive imaging studies play a critical role in the presurgical evaluation of patients with drug-resistant temporal lobe epilepsy (TLE), particularly in helping to lateralize the seizure focus. Arterial Spin Labeling (ASL) MRI has been widely used to non-invasively study cerebral blood flow (CBF), with somewhat variable interictal alterations reported in TLE. Here, we compare temporal lobe subregional interictal perfusion and symmetry in lesional (MRI+) and non-lesional (MRI-) TLE compared to healthy volunteers (HVs). METHODS Twenty TLE patients (9 MRI+, 11 MRI-) and 14 HVs under went 3 T Pseudo-Continuous ASL MRI through an epilepsy imaging research protocol at the NIH Clinical Center. We compared normalized CBF and absolute asymmetry indices in multiple temporal lobe subregions. RESULTS Compared to HVs, both MRI+ and MRI- TLE groups demonstrated significant ipsilateral mesial and lateral temporal hypoperfusion, specifically in the hippocampal and anterior temporal neocortical subregions, with additional hypoperfusion in the ipsilateral parahippocampal gyrus in the MRI+ and contralateral hippocampus in the MRI- TLE groups. Contralateral to the seizure focus, there was significant relative hypoperfusion in multiple subregions in the MRI- compared to the MRI+ TLE groups. The MRI+ group therefore had significantly greater asymmetry across multiple temporal subregions compared to the MRI- TLE and HV groups. No significant differences in asymmetry were found between the MRI- TLE and HV groups. CONCLUSION We found a similar extent of interictal ipsilateral temporal hypoperfusion in MRI+ and MRI- TLE. However, significantly increased asymmetries were found only in the MRI+ group due to differences in perfusion contralateral to the seizure focus between the patient groups. The lack of asymmetry in the MRI- group may negatively impact the utility of interictal ASL for seizure focus lateralization in this patient population.
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Affiliation(s)
- Frederika Rentzeperis
- Office of the Clinical Director, NINDS, National Institutes of Health, Bethesda, MD, USA
| | - Myriam Abdennadher
- Boston Medical Center, Boston University School of Medicine, Boston, MA, USA
| | - Kathryn Snyder
- Office of the Clinical Director, NINDS, National Institutes of Health, Bethesda, MD, USA
| | - Kate Dembny
- Office of the Clinical Director, NINDS, National Institutes of Health, Bethesda, MD, USA
| | - Shervin Abdollahi
- Office of the Clinical Director, NINDS, National Institutes of Health, Bethesda, MD, USA
| | - Kareem A Zaghloul
- Surgical Neurology Branch, NINDS, National Institutes of Health, USA
| | - Lalith Talagala
- NIH MRI Research Facility, NINDS, National Institutes of Health, USA
| | | | - Sara K Inati
- Office of the Clinical Director, NINDS, National Institutes of Health, Bethesda, MD, USA.
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Ajčević M, Iscra K, Furlanis G, Michelutti M, Miladinović A, Buoite Stella A, Ukmar M, Cova MA, Accardo A, Manganotti P. Cerebral hypoperfusion in post-COVID-19 cognitively impaired subjects revealed by arterial spin labeling MRI. Sci Rep 2023; 13:5808. [PMID: 37037833 PMCID: PMC10086005 DOI: 10.1038/s41598-023-32275-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/24/2023] [Indexed: 04/12/2023] Open
Abstract
Cognitive impairment is one of the most prevalent symptoms of post Severe Acute Respiratory Syndrome COronaVirus 2 (SARS-CoV-2) state, which is known as Long COVID. Advanced neuroimaging techniques may contribute to a better understanding of the pathophysiological brain changes and the underlying mechanisms in post-COVID-19 subjects. We aimed at investigating regional cerebral perfusion alterations in post-COVID-19 subjects who reported a subjective cognitive impairment after a mild SARS-CoV-2 infection, using a non-invasive Arterial Spin Labeling (ASL) MRI technique and analysis. Using MRI-ASL image processing, we investigated the brain perfusion alterations in 24 patients (53.0 ± 14.5 years, 15F/9M) with persistent cognitive complaints in the post COVID-19 period. Voxelwise and region-of-interest analyses were performed to identify statistically significant differences in cerebral blood flow (CBF) maps between post-COVID-19 patients, and age and sex matched healthy controls (54.8 ± 9.1 years, 13F/9M). The results showed a significant hypoperfusion in a widespread cerebral network in the post-COVID-19 group, predominantly affecting the frontal cortex, as well as the parietal and temporal cortex, as identified by a non-parametric permutation testing (p < 0.05, FWE-corrected with TFCE). The hypoperfusion areas identified in the right hemisphere regions were more extensive. These findings support the hypothesis of a large network dysfunction in post-COVID subjects with cognitive complaints. The non-invasive nature of the ASL-MRI method may play an important role in the monitoring and prognosis of post-COVID-19 subjects.
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Affiliation(s)
- Miloš Ajčević
- Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | - Katerina Iscra
- Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | - Giovanni Furlanis
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy
| | - Marco Michelutti
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy
| | | | - Alex Buoite Stella
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy
| | - Maja Ukmar
- Radiology Unit, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy
| | - Maria Assunta Cova
- Radiology Unit, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy
| | - Agostino Accardo
- Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | - Paolo Manganotti
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Trieste University Hospital-ASUGI, University of Trieste, Trieste, Italy.
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Wada T, Mori H, Shindo K. Serial assessment of multimodality imaging in anti-leucine-rich glioma-inactivated 1 antibody encephalitis: A case report. eNeurologicalSci 2022; 29:100426. [PMID: 36161067 PMCID: PMC9494171 DOI: 10.1016/j.ensci.2022.100426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/29/2022] [Accepted: 09/10/2022] [Indexed: 11/29/2022] Open
Abstract
In autoimmune encephalitis, abnormalities of diffusion-weighted imaging (DWI), fluid-attenuated inversion recovery (FLAIR), arterial spin labeling (ASL) in magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT) and 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) have been reported. However, there are few studies of long-term follow-up of imaging. We report a case of anti-leucine-rich glioma-inactivated 1 antibody encephalitis whose MRI (DWI, FLAIR and ASL), 99mTcHM-PAO SPECT (PAO-SPECT) and 18F-FDG-PET were evaluated through the clinical course. ASL, PAO-SPECT and 18F-FDG-PET consistently showed abnormalities in almost the same area. Serial assessment of these imaging modalities is useful in evaluating disease activity and efficacy of treatment. We followed up anti-LGI1 encephalitis by comparing multimodality imaging. ASL, PAO-SPECT and 18F-FDG-PET showed similar trends of abnormalities. Serial assessment of imaging was useful in evaluating disease activity.
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Affiliation(s)
- Takafumi Wada
- Department of Neurology, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki/Okayama, 710-8602, Japan
| | - Hitoshi Mori
- Department of Neurology, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki/Okayama, 710-8602, Japan
| | - Katsuro Shindo
- Department of Neurology, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki/Okayama, 710-8602, Japan
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Daftari Besheli L, Ahmed A, Hamam O, Luna L, Sun LR, Urrutia V, Hillis AE, Tekes-Brady A, Yedavalli V. Arterial Spin Labeling technique and clinical applications of the intracranial compartment in stroke and stroke mimics - A case-based review. Neuroradiol J 2022; 35:437-453. [PMID: 35635512 PMCID: PMC9437493 DOI: 10.1177/19714009221098806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023] Open
Abstract
Magnetic resonance imaging perfusion (MRP) techniques can improve the selection of acute ischemic stroke patients for treatment by estimating the salvageable area of decreased perfusion, that is, penumbra. Arterial spin labeling (ASL) is a noncontrast MRP technique that is used to assess cerebral blood flow without the use of intravenous gadolinium contrast. Thus, ASL is of particular interest in stroke imaging. This article will review clinical applications of ASL in stroke such as assessment of the core infarct and penumbra, localization of the vascular occlusion, and collateral status. Given the nonspecific symptoms that patients can present with, differentiating between stroke and a stroke mimic is a diagnostic dilemma. ASL not only helps in differentiating stroke from stroke mimic but also can be used to specify the exact mimic when used in conjunction with the symptomatology and structural imaging. In addition to a case-based overview of clinical applications of the ASL in stroke and stroke mimics in this article, the more commonly used ASL labeling techniques as well as emerging ASL techniques, future developments, and limitations will be reviewed.
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Affiliation(s)
| | - Amara Ahmed
- Florida State University College of
Medicine, Tallahassee, FL, USA
| | - Omar Hamam
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | - Licia Luna
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | - Lisa R Sun
- Johns Hopkins School of
Medicine, Baltimore, MD, USA
| | | | - Argye E Hillis
- Johns Hopkins University School of
Medicine, Baltimore, MD, USA
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Manganotti P, Furlanis G, Cova MA, Olivo S, Dore F, Sartori A, Naccarato M. Isolated aphasic status epilepticus: CT perfusion, SPECT and EEG reveal neurovascular coupling and support the differential diagnosis. Epileptic Disord 2022; 24:549-554. [PMID: 35653085 DOI: 10.1684/epd.2022.1421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/03/2022] [Indexed: 11/08/2023]
Abstract
Objective Among the clinical manifestations of stroke mimics, isolated aphasia is one of the most challenging due to its aetiopathogenic diagnosis. This short communication describes a specific perfusion and brain oscillatory pattern in a challenging case of prolonged isolated aphasia caused by status epilepticus, jointly investigated by computed tomography (CT) perfusion, single-photon emission computerized tomography (SPECT)/CT and EEG qualitative and quantitative analysis. Methods We discuss the different patterns of perfusion neuroimaging and EEG between SE and ischaemic stroke or postictal (Todd's)-related isolated aphasia, and propose these differences as a basis to support the differential diagnosis. Results The pattern associated with SE was characterized by focal hyperperfusion on CT perfusion maps (the left mean transit time was shorter with >10% asymmetry, and left cerebral blood volume and cerebral blood flow increased or slightly altered, relative to the contralateral side) and SPECT (focal left temporal hyperperfusion), without any early ischaemic signs on non-enhanced CT, while the EEG showed a predominant left hemispheric slow delta power. The aforementioned perfusion pattern contrasts with postictal epileptic Todd's phenomenon, which is characterized by hypoperfusion on CT perfusion (the mean transit time is prolonged and cerebral blood volume and cerebral blood flow are reduced, compared to the contralateral hemisphere) and SPECT (focal hypoperfusion), not restricted to the specific vascular territories. Significance CT perfusion patterns may add valuable information to support the differential diagnosis of status epilepticus, rather than acute ischaemic stroke or postictal Todd's phenomenon, in cases with challenging symptoms of prolonged isolated aphasia.
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Buch K, Hakimelahi R, Locascio JJ, Bolar DS, Gonzalez RG, Schaefer PW. Clinical utility of arterial spin labeling perfusion images in the emergency department for the work-up of stroke-like symptoms. Neuroradiology 2021; 64:925-934. [PMID: 34664110 DOI: 10.1007/s00234-021-02835-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/11/2021] [Indexed: 11/25/2022]
Abstract
PURPOSE To assess the utility of ASL in evaluating patients presenting to the ED with stroke-like symptoms. METHODS ASL and DWI images from 526 consecutive patients presenting to the ED with acute stroke symptoms were retrospectively reviewed. DWI images were evaluated for volume of restricted diffusion using ABC/2. ASL maps were evaluated for decreased, normal, or increased signal. The volume of decreased ASL signal was calculated using the same ABC/2 technique. The volume of decreased ASL signal was correlated with the volume of DWI signal abnormality to identify cases of mismatch (DWI:ASL ratio > 1.8) and to correlate this mismatch with infarct growth on imaging follow-up. NIHSS, length of hospital stay, mRS, and future admission for acute stroke-like symptoms were recorded. Correlations between ASL abnormalities and clinical parameters were evaluated using a two-tailed t-test. RESULTS Of the 526 patients presenting with acute stroke symptoms, 136 patients had an abnormal ASL scan and 388 patients had a normal ASL scan. Of the 136 patients with abnormal ASL, 84 patients had low ASL signal with 79 of these being related to acute infarcts. Elevated ASL signal was seen in 52 patients, of which 30 of these patients had reperfusion hyperemia related to acute infarctions. ASL had a negative predictive value of 94% for evaluating patients with acute ischemic stroke. A subset of patients with abnormal ASL scans with a discharge diagnosis of acute infarction were found to have an ASL:DWI mismatch (ratio > 1.8) and demonstrated significant lesion growth on follow-up imaging (57%). This included some patients who exhibited low ASL signal before development of diffusion restriction (infarction). CONCLUSION In patients presenting to the ED with acute stroke symptoms, ASL provides information not available with DWI alone. The NPV of ASL for evaluating patients with acute ischemia was 94%.
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Affiliation(s)
- Karen Buch
- Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Gray 241 G, Boston, MA, 02114, USA.
| | - Reza Hakimelahi
- Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Gray 241 G, Boston, MA, 02114, USA
| | - Joseph J Locascio
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Divya S Bolar
- Department of Radiology, University of California San Diego School of Medicine, La Jolla, CA, USA
| | - R Giliberto Gonzalez
- Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Gray 241 G, Boston, MA, 02114, USA
| | - Pamela W Schaefer
- Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Gray 241 G, Boston, MA, 02114, USA
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9
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Paschoal AM, da Silva PHR, Rondinoni C, Arrigo IV, Paiva FF, Leoni RF. Semantic verbal fluency brain network: delineating a physiological basis for the functional hubs using dual-echo ASL and graph theory approach. J Neural Eng 2021; 18. [PMID: 34087805 DOI: 10.1088/1741-2552/ac0864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 06/04/2021] [Indexed: 01/07/2023]
Abstract
Objective. Semantic verbal fluency (SFV) is a cognitive process that engages and modulates specific brain areas related to language comprehension and production, decision making, response inhibition, and memory retrieval. The impairment of the brain network responsible for these functions is related to various neurological conditions, and different strategies have been proposed to assess SVF-related deficits in such diseases. In the present study, the concomitant changes of brain perfusion and functional connectivity were investigated during the resting state and SVF task performance.Approach. Arterial spin labeling (ASL), a perfusion-based magnetic resonance imaging (MRI) method, was used with a pseudocontinuous labeling approach and dual-echo readout in 28 healthy right-handed Brazilian Portuguese speakers. The acquisition was performed in a resting state condition and during the performance of a SVF task.Main results. During task performance, a significant increase in cerebral blood flow (CBF) was observed in language-related regions of the frontal lobe, including Brodmann's areas 6, 9, 45, and 47, associated with semantic processing, word retrieval, and speech motor programming. Such regions, along with the posterior cingulate, showed a crucial role in the SVF functional network, assessed by seed-to-voxel and graph analysis. Our approach successfully overcame the generalization problem regarding functional MRI (fMRI) graph analysis with cognitive, task-based paradigms. Moreover, the CBF maps enabled the functional assessment of orbital frontal and temporal regions commonly affected by magnetic susceptibility artifacts in conventional T2*-weighted fMRI approaches.Significance. Our results demonstrated the capability of ASL to evaluate perfusion alterations and functional patterns simultaneously regarding the SVF network providing a quantitative physiological basis to functional hubs in this network, which may support future clinical studies.
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Affiliation(s)
- André Monteiro Paschoal
- LIM44, Instituto e Departamento de Radiologia, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil.,Inbrain Lab, Department of Physics, FFCLRP, University of Sao Paulo, Ribeirao Preto, Brazil
| | | | - Carlo Rondinoni
- Inbrain Lab, Department of Physics, FFCLRP, University of Sao Paulo, Ribeirao Preto, Brazil
| | | | | | - Renata Ferranti Leoni
- Inbrain Lab, Department of Physics, FFCLRP, University of Sao Paulo, Ribeirao Preto, Brazil
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Lee DA, Lee HJ, Kim HC, Park KM. Temporal lobe epilepsy with or without hippocampal sclerosis: Structural and functional connectivity using advanced MRI techniques. J Neuroimaging 2021; 31:973-980. [PMID: 34110654 DOI: 10.1111/jon.12898] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/18/2021] [Accepted: 05/27/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE The aim of this study was to investigate the differences in structural connectivity based on diffusion tensor imaging (DTI) and functional connectivity based on arterial spin labeling (ASL) MRI between temporal lobe epilepsy (TLE) patients with and without hippocampal sclerosis (HS). METHODS We enrolled 50 patients with TLE, including 25 patients with HS and 25 patients without HS, who underwent brain MRI, including DTI and ASL. We calculated the network parameters of structural connectivity based on DTI and functional connectivity based on ASL using a graph theoretical analysis. The parameters included global network measures (radius, diameter, characteristic path length, global efficiency, local efficiency, mean clustering coefficient, transitivity, assortative coefficient, and small-worldness index) and a local network measure (betweenness centrality). RESULTS The global and local network measures of structural connectivity were not different between TLE patients with and without HS. However, significant differences in functional connectivity existed between the two groups. The radius and diameter of the global network measures in the TLE patients with HS were significantly increased compared with those without HS (4.140 vs. 3.140, p = 0.045; 6.812 vs. 5.132, p = 0.049; respectively). No differences were detected between other global network measures of functional connectivity and local network measure. CONCLUSIONS Significant differences in global network measures of functional connectivity based on ASL existed between TLE patients with and without HS. These findings suggest that TLE patients with HS exhibit a more disconnected functional brain network than those without HS.
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Affiliation(s)
- Dong Ah Lee
- Department of Neurology and Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
| | - Ho-Joon Lee
- Department of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
| | - Hyung Chan Kim
- Department of Neurology and Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
| | - Kang Min Park
- Department of Neurology and Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
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Gajdoš M, Říha P, Kojan M, Doležalová I, Mutsaerts HJMM, Petr J, Rektor I. Epileptogenic zone detection in MRI negative epilepsy using adaptive thresholding of arterial spin labeling data. Sci Rep 2021; 11:10904. [PMID: 34035336 PMCID: PMC8149682 DOI: 10.1038/s41598-021-89774-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/23/2021] [Indexed: 11/09/2022] Open
Abstract
Drug-resistant epilepsy is a diagnostic and therapeutic challenge, mainly in patients with negative MRI findings. State-of-the-art imaging methods complement standard epilepsy protocols with new information and help epileptologists to increase the reliability of their decisions. In this study, we investigate whether arterial spin labeling (ASL) perfusion MRI can help localize the epileptogenic zone (EZ). To that end, we developed an image processing method to detect the EZ as an area with hypoperfusion relative to the contralateral unaffected side, using subject-specific thresholding of the asymmetry index in ASL images. We demonstrated three thresholding criteria (termed minimal product criterion, minimal distance criterion, and elbow criterion) on 29 patients with MRI-negative epilepsy (age 32.98 ± 10.4 years). The minimal product criterion showed optimal results in terms of positive predictive value (mean 0.12 in postoperative group and 0.22 in preoperative group) and true positive rate (mean 0.71 in postoperative group and 1.82 in preoperative group). Additionally, we found high accuracy in determining the EZ side (mean 0.86 in postoperative group and 0.73 in preoperative group out of 1.00). ASL can be easily incorporated into the standard presurgical MR protocol, and it provides an additional benefit in EZ localization.
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Affiliation(s)
- Martin Gajdoš
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic
| | - Pavel Říha
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic.,Department of Neurology, Brno Epilepsy Center, St. Anne's University Hospital and Medical Faculty of Masaryk University, Pekařská 53, Brno, 656 91, Czech Republic
| | - Martin Kojan
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic.,Department of Neurology, Brno Epilepsy Center, St. Anne's University Hospital and Medical Faculty of Masaryk University, Pekařská 53, Brno, 656 91, Czech Republic
| | - Irena Doležalová
- Department of Neurology, Brno Epilepsy Center, St. Anne's University Hospital and Medical Faculty of Masaryk University, Pekařská 53, Brno, 656 91, Czech Republic
| | - Henk J M M Mutsaerts
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Center, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Department of Radiology and Nuclear Medicine, University Hospital Ghent, Ghent, Belgium
| | - Jan Petr
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Ivan Rektor
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic. .,Department of Neurology, Brno Epilepsy Center, St. Anne's University Hospital and Medical Faculty of Masaryk University, Pekařská 53, Brno, 656 91, Czech Republic.
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12
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Lim HK, You N, Bae S, Kang BM, Shon YM, Kim SG, Suh M. Differential contribution of excitatory and inhibitory neurons in shaping neurovascular coupling in different epileptic neural states. J Cereb Blood Flow Metab 2021; 41:1145-1161. [PMID: 32669018 PMCID: PMC8054729 DOI: 10.1177/0271678x20934071] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Understanding the neurovascular coupling (NVC) underlying hemodynamic changes in epilepsy is crucial to properly interpreting functional brain imaging signals associated with epileptic events. However, how excitatory and inhibitory neurons affect vascular responses in different epileptic states remains unknown. We conducted real-time in vivo measurements of cerebral blood flow (CBF), vessel diameter, and excitatory and inhibitory neuronal calcium signals during recurrent focal seizures. During preictal states, decreases in CBF and arteriole diameter were closely related to decreased γ-band local field potential (LFP) power, which was linked to relatively elevated excitatory and reduced inhibitory neuronal activity levels. Notably, this preictal condition was followed by a strengthened ictal event. In particular, the preictal inhibitory activity level was positively correlated with coherent oscillating activity specific to inhibitory neurons. In contrast, ictal states were characterized by elevated synchrony in excitatory neurons. Given these findings, we suggest that excitatory and inhibitory neurons differentially contribute to shaping the ictal and preictal neural states, respectively. Moreover, the preictal vascular activity, alongside with the γ-band, may reflect the relative levels of excitatory and inhibitory neuronal activity, and upcoming ictal activity. Our findings provide useful insights into how perfusion signals of different epileptic states are related in terms of NVC.
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Affiliation(s)
- Hyun-Kyoung Lim
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biological Sciences, Sungkyunkwan University, Suwon, South Korea
| | - Nayeon You
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
| | - Sungjun Bae
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
| | - Bok-Man Kang
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
| | - Young-Min Shon
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Seong-Gi Kim
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
| | - Minah Suh
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea.,Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, Suwon, South Korea.,Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University, Suwon, South Korea
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13
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Kojan M, Gajdoš M, Říha P, Doležalová I, Řehák Z, Rektor I. Arterial Spin Labeling is a Useful MRI Method for Presurgical Evaluation in MRI-Negative Focal Epilepsy. Brain Topogr 2021; 34:504-510. [PMID: 33783670 DOI: 10.1007/s10548-021-00833-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 03/16/2021] [Indexed: 12/25/2022]
Abstract
Arterial spin labeling (ASL) is an MRI technique measuring brain perfusion using magnetically labeled blood as a tracer. The clinical utility of ASL for presurgical evaluation in non-lesional epilepsy as compared with the quantitative analysis of interictal [18F] fluorodeoxyglucose PET (FDG-PET) was studied. In 10 patients (4 female; median age 29 years) who underwent a complete presurgical evaluation followed by surgical resection, the presurgical FDG-PET and ASL scans were compared with the resection masks using asymmetry index (AI) maps. The positive predictive value (PPV) and sensitivity (SEN), were calculated from the number of voxels inside the mask (true positive), and outside the mask (false positive). The comparison of the PPVs showed better PPV in 6 patients using ASL and in 2 patients with PET. SEN was better in 4 patients using ASL and in 5 patients with PET. According to the Wilcoxon signed rank test for PPV (p = 0.74) and for SEN (p = 0.43), these methods have similar predictive power. ASL is a useful method for presurgical evaluation in non-lesional epilepsy. The main benefits of ASL over PET are that it avoids radiation exposure for patients, and it offers lower costs, higher availability, and better time efficiency.
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Affiliation(s)
- Martin Kojan
- Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic
| | - Martin Gajdoš
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic
| | - Pavel Říha
- Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic
| | - Irena Doležalová
- Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Zdeněk Řehák
- Department of Nuclear Medicine, Masaryk Memorial Cancer Institute, Brno, Czech Republic
| | - Ivan Rektor
- Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic.
- CEITEC - Central European Institute of Technology, Neuroscience Center, Masaryk University, Brno, Czech Republic.
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14
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Mareček R, Říha P, Bartoňová M, Kojan M, Lamoš M, Gajdoš M, Vojtíšek L, Mikl M, Bartoň M, Doležalová I, Pail M, Strýček O, Pažourková M, Brázdil M, Rektor I. Automated fusion of multimodal imaging data for identifying epileptogenic lesions in patients with inconclusive magnetic resonance imaging. Hum Brain Mapp 2021; 42:2921-2930. [PMID: 33772952 PMCID: PMC8127142 DOI: 10.1002/hbm.25413] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/15/2021] [Accepted: 03/09/2021] [Indexed: 12/13/2022] Open
Abstract
Many methods applied to data acquired by various imaging modalities have been evaluated for their benefit in localizing lesions in magnetic resonance (MR) negative epilepsy patients. No approach has proven to be a stand-alone method with sufficiently high sensitivity and specificity. The presented study addresses the potential benefit of the automated fusion of results of individual methods in presurgical evaluation. We collected electrophysiological, MR, and nuclear imaging data from 137 patients with pharmacoresistant MR-negative/inconclusive focal epilepsy. A subgroup of 32 patients underwent surgical treatment with known postsurgical outcomes and histopathology. We employed a Gaussian mixture model to reveal several classes of gray matter tissue. Classes specific to epileptogenic tissue were identified and validated using the surgery subgroup divided into two disjoint sets. We evaluated the classification accuracy of the proposed method at a voxel-wise level and assessed the effect of individual methods. The training of the classifier resulted in six classes of gray matter tissue. We found a subset of two classes specific to tissue located in resected areas. The average classification accuracy (i.e., the probability of correct classification) was significantly higher than the level of chance in the training group (0.73) and even better in the validation surgery subgroup (0.82). Nuclear imaging, diffusion-weighted imaging, and source localization of interictal epileptic discharges were the strongest methods for classification accuracy. We showed that the automatic fusion of results can identify brain areas that show epileptogenic gray matter tissue features. The method might enhance the presurgical evaluations of MR-negative epilepsy patients.
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Affiliation(s)
- Radek Mareček
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Pavel Říha
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Medical Faculty, Masaryk University, Brno, Czech Republic
| | - Michaela Bartoňová
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Medical Faculty, Masaryk University, Brno, Czech Republic
| | - Martin Kojan
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Medical Faculty, Masaryk University, Brno, Czech Republic.,Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Martin Lamoš
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Martin Gajdoš
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Lubomír Vojtíšek
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Michal Mikl
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Marek Bartoň
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
| | - Irena Doležalová
- Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Martin Pail
- Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Ondřej Strýček
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Medical Faculty, Masaryk University, Brno, Czech Republic.,Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Marta Pažourková
- Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Milan Brázdil
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Ivan Rektor
- Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.,Brno Epilepsy Center, First Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic
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15
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Arterial spin-labelling and magnetic resonance spectroscopy as imaging biomarkers for detection of epileptogenic zone in non-lesional focal impaired awareness epilepsy. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2020. [DOI: 10.1186/s43055-020-00326-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
The proper identification of an epileptic focus is a pivotal diagnostic issue; particularly in non-lesional focal impaired awareness epilepsy (FIAE). Seizures are usually accompanied by alterations of regional cerebral blood flow (rCBF) and metabolism. Arterial spin labeling-MRI (ASL-MRI) and proton magnetic resonance spectroscopy (1H-MRS) are MRI techniques that can, non-invasively, define the regions of cerebral perfusion and metabolic changes, respectively. The aim of the current study was to recognize the epileptogenic zone in patients with non-lesional FIAE by evaluating the interictal changes in rCBF and cerebral metabolic alterations, using PASL-MRI and 1H-MRS.
Results
For identification of the epileptogenic zone, increased ASLAI% assessed by PASL-MRI (at a cut-off value ≥ 5.96%) showed 95.78% accuracy, and increased %AF (at a cut-off value ≥ 9.98%) showed 98.14% accuracy, while decreased NAA/(Cho + Cr) ratio estimated by multi-voxels (MV) 1H-MRS (at a cut-off value ≥ 0.59) showed 97.74% accuracy. Moreover, the combined use of PASL-MRI and MV 1H-MRS yielded 100% sensitivity, 98.45% specificity and 98.86% accuracy.
Conclusion
The combined use of PASL-MRI and MV 1H-MRS can be considered as in-vivo proficient bio-marker for proper identification of epileptogenic zone in patients with non-lesional FIAE.
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16
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Perera T, Gaxiola-Valdez I, Singh S, Peedicail J, Sandy S, Lebel RM, Li E, Milne-Ives M, Szostakiwskyj J, Federico P. Localizing the seizure onset zone by comparing patient postictal hypoperfusion to healthy controls. J Neurosci Res 2020; 98:1517-1531. [PMID: 32476173 DOI: 10.1002/jnr.24646] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 04/23/2020] [Accepted: 05/03/2020] [Indexed: 11/10/2022]
Abstract
Arterial spin labeling (ASL) MRI can provide seizure onset zone (SOZ) localizing information in up to 80% of patients. Clinical implementation of this technique is limited by the need to obtain two scans per patient: a postictal scan that is subtracted from an interictal scan. We aimed to determine whether it is possible to limit the number of ASL scans to one per patient by comparing patient postictal ASL scans to baseline scans of 100 healthy controls. Eighteen patients aged 20-55 years underwent ASL MRI <90 min after a seizure and during the interictal period. Each postictal cerebral blood flow (CBF) map was statistically compared to average baseline CBF maps from 100 healthy controls (pvcASL; patient postictal CBF vs. control baseline CBF). The pvcASL maps were compared to subtraction ASL maps (sASL; patient baseline CBF minus patient postictal CBF). Postictal CBF reductions from pvcASL and sASL maps were seen in 17 of 18 (94.4%) and 14 of 18 (77.8%) patients, respectively. Maximal postictal hypoperfusion seen in pvcASL and sASL maps was concordant with the SOZ in 10 of 17 (59%) and 12 of 14 (86%) patients, respectively. In seven patients, both pvcASL and sASL maps showed similar results. In two patients, sASL showed no significant hypoperfusion, while pvcASL showed significant hypoperfusion concordant with the SOZ. We conclude that pvcASL is clinically useful and although it may have a lower overall concordance rate than sASL, pvcASL does provide localizing or lateralizing information for specific cases that would be otherwise missed through sASL.
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Affiliation(s)
- Tefani Perera
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada
| | - Ismael Gaxiola-Valdez
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada
| | - Shaily Singh
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Joseph Peedicail
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Sherry Sandy
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - R Marc Lebel
- GE Healthcare, Calgary, Calgary, AB, Canada.,Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Emmy Li
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada
| | - Madison Milne-Ives
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada
| | | | - Paolo Federico
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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17
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Diagnostica per immagini funzionale nell’epilessia. Neurologia 2020. [DOI: 10.1016/s1634-7072(20)43296-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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18
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CT perfusion and EEG patterns in patients with acute isolated aphasia in seizure-related stroke mimics. Seizure 2019; 71:110-115. [DOI: 10.1016/j.seizure.2019.07.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/02/2019] [Accepted: 07/03/2019] [Indexed: 11/22/2022] Open
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19
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Stragapede L, Furlanis G, Ajčević M, Ridolfi M, Caruso P, Naccarato M, Ukmar M, Manganotti P. Brain oscillatory activity and CT perfusion in hyper-acute ischemic stroke. J Clin Neurosci 2019; 69:184-189. [PMID: 31409548 DOI: 10.1016/j.jocn.2019.07.068] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 07/29/2019] [Indexed: 01/24/2023]
Abstract
OBJECTIVES The combined use of perfusion neuroimaging and brain oscillatory activity may provide a better clinical picture of neurovascular coupling of the injured area in ischemic stroke. The aim is to assess stroke-related topographic electroencephalography (EEG) changes during the earliest phase of ischemic stroke and to compare them with hypoperfusion identified by computer tomography perfusion (CTP). PATIENTS AND METHODS The study included 15 patients with ischemic stroke, who underwent both CTP and EEG recording within 4.5 h. Topographic representation of power for each band was calculated and compared with hypoperfusion areas estimated by CTP maps. RESULTS Predominance of slow delta frequencies was found in all patients. The main finding is the agreement between slow rhythms hemispheric prevalence on EEG maps and cerebral hypoperfusion area identified using CTP. CONCLUSION The results of this preliminary study show that the combined use of EEG and CTP, as highly available techniques, in acute ischemic stroke may be helpful in clinical practice and provide information about functional and metabolic aspects of brain involvement. The joint use of these methodologies may give a better clinical insight of the functionality of injured area in the hyperacute phase.
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Affiliation(s)
- Lara Stragapede
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy.
| | - Giovanni Furlanis
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Miloš Ajčević
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Mariana Ridolfi
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Paola Caruso
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Marcello Naccarato
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Maja Ukmar
- Radiology Unit, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
| | - Paolo Manganotti
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, University of Trieste, Trieste, Italy
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20
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CT perfusion measurement of postictal hypoperfusion: localization of the seizure onset zone and patterns of spread. Neuroradiology 2019; 61:991-1010. [PMID: 31152191 DOI: 10.1007/s00234-019-02227-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE Seizures are often followed by a period of transient neurological dysfunction and postictal alterations in cerebral blood flow may underlie these symptoms. Recent animal studies have shown reduced local cerebral blood flow at the seizure onset zone (SOZ) lasting approximately 1 h following seizures. Using arterial spin labelling (ASL) MRI, we observed postictal hypoperfusion at the SOZ in 75% of patients. The clinical implementation of ASL as a tool to identify the SOZ is hampered by the limited availability of MRI on short notice. Computed tomography perfusion (CTP) also measures blood flow and may circumvent the logistical limitations of MRI. Thus, we aimed to measure the extent of postictal hypoperfusion using CTP. METHODS Fourteen adult patients with refractory focal epilepsy admitted for presurgical evaluation were prospectively recruited and underwent CTP scanning within 80 min of a habitual seizure. Patients also underwent a baseline scan after they were seizure-free for > 24 h. The acquired scans were qualitatively assessed by two reviewers by visual inspection and quantitatively assessed through a subtraction pipeline to identify areas of significant postictal hypoperfusion. RESULTS Postictal blood flow reductions of > 15 ml/100 g-1/min-1 were seen in 12/13 patients using the quantitative method of analysis. In 10/12 patients, the location of the hypoperfusion was partially or fully concordant with the presumed SOZ. In all patients, additional areas of scattered hypoperfusion were seen in areas corresponding to seizure spread. CONCLUSION CTP can reliably measure postictal hypoperfusion which is maximal at the presumed SOZ.
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21
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Sone D, Maikusa N, Sato N, Kimura Y, Ota M, Matsuda H. Similar and Differing Distributions Between 18F-FDG-PET and Arterial Spin Labeling Imaging in Temporal Lobe Epilepsy. Front Neurol 2019; 10:318. [PMID: 31001198 PMCID: PMC6456651 DOI: 10.3389/fneur.2019.00318] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 03/14/2019] [Indexed: 01/11/2023] Open
Abstract
Background: Despite the increasing use of arterial spin labeling (ASL) in patients with epilepsy, little is known about its brain regional distribution pattern, including diaschisis, and its correspondence with FDG-PET. Here, we investigated the regional match and mismatch between FDG-PET and ASL in temporal lobe epilepsy (TLE). Methods: We recruited 27 patients with unilateral TLE, who underwent inter-ictal ASL and FDG-PET scans. These images were spatially normalized using Statistical Parametric Mapping 12, and the regional values in both ASL and FDG-PET were calculated using PMOD software within 20 volumes of interest (VOIs), including the temporal lobe, adjacent cortices, subcortical structures, and cerebellum. ASL images of 37 healthy controls were also analyzed and compared. Results: Whereas, ASL showed significant side differences, mainly in the temporal and frontal lobes, the significant abnormalities in FDG-PET were more widespread and included the insula and supramarginal gyrus. Ipsilateral thalamic reduction was found in FDG-PET only. The detectability of the focus side compared with the contralateral side was generally higher in FDG-PET. The discriminative values in ASL compared with healthy controls were higher in temporal neocortex and amygdala VOIs. Conclusions: There are similar and differing regional distributions between FDG-PET and ASL in TLE, possibly reflecting regional match and mismatch of cerebral blood flow and metabolism. At this stage, it seems that ASL couldn't present comparable clinical usefulness with FDG-PET. These findings deepen our knowledge of ASL imaging and are potentially useful for its further application.
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Affiliation(s)
- Daichi Sone
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Norihide Maikusa
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Noriko Sato
- Department of Radiology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Yukio Kimura
- Department of Radiology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Miho Ota
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan.,Division of Clinical Medicine, Department of Neuropsychiatry, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Hiroshi Matsuda
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
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22
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Boscolo Galazzo I, Storti SF, Barnes A, De Blasi B, De Vita E, Koepp M, Duncan JS, Groves A, Pizzini FB, Menegaz G, Fraioli F. Arterial Spin Labeling Reveals Disrupted Brain Networks and Functional Connectivity in Drug-Resistant Temporal Epilepsy. Front Neuroinform 2019; 12:101. [PMID: 30894811 PMCID: PMC6414423 DOI: 10.3389/fninf.2018.00101] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 12/12/2018] [Indexed: 01/08/2023] Open
Abstract
Resting-state networks (RSNs) and functional connectivity (FC) have been increasingly exploited for mapping brain activity and identifying abnormalities in pathologies, including epilepsy. The majority of studies currently available are based on blood-oxygenation-level-dependent (BOLD) contrast in combination with either independent component analysis (ICA) or pairwise region of interest (ROI) correlations. Despite its success, this approach has several shortcomings as BOLD is only an indirect and non-quantitative measure of brain activity. Conversely, promising results have recently been achieved by arterial spin labeling (ASL) MRI, primarily developed to quantify brain perfusion. However, the wide application of ASL-based FC has been hampered by its complexity and relatively low robustness to noise, leaving several aspects of this approach still largely unexplored. In this study, we firstly aimed at evaluating the effect of noise reduction on spatio-temporal ASL analyses and quantifying the impact of two ad-hoc processing pipelines (basic and advanced) on connectivity measures. Once the optimal strategy had been defined, we investigated the applicability of ASL for connectivity mapping in patients with drug-resistant temporal epilepsy vs. controls (10 per group), aiming at revealing between-group voxel-wise differences in each RSN and ROI-wise FC changes. We first found ASL was able to identify the main network (DMN) along with all the others generally detected with BOLD but never previously reported from ASL. For all RSNs, ICA-based denoising (advanced pipeline) allowed to increase their similarity with the corresponding BOLD template. ASL-based RSNs were visibly consistent with literature findings; however, group differences could be identified in the structure of some networks. Indeed, statistics revealed areas of significant FC decrease in patients within different RSNs, such as DMN and cerebellum (CER), while significant increases were found in some cases, such as the visual networks. Finally, the ROI-based analyses identified several inter-hemispheric dysfunctional links (controls > patients) mainly between areas belonging to the DMN, right-left thalamus and right-left temporal lobe. Conversely, fewer connections, predominantly intra-hemispheric, showed the opposite pattern (controls < patients). All these elements provide novel insights into the pathological modulations characterizing a "network disease" as epilepsy, shading light on the importance of perfusion-based approaches for identifying the disrupted areas and communications between brain regions.
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Affiliation(s)
| | | | - Anna Barnes
- Institute of Nuclear Medicine, University College London, London, United Kingdom
| | - Bianca De Blasi
- Department of Medical Physics, University College London, London, United Kingdom
| | - Enrico De Vita
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's Health Partners, King's College London, London, United Kingdom
| | - Matthias Koepp
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, United Kingdom
| | - John Sidney Duncan
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, United Kingdom
| | - Ashley Groves
- Institute of Nuclear Medicine, University College London, London, United Kingdom
| | | | - Gloria Menegaz
- Department of Computer Science, University of Verona, Verona, Italy
| | - Francesco Fraioli
- Institute of Nuclear Medicine, University College London, London, United Kingdom
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Li X, Yuan J, Liu L, Hu W. Antibody-LGI 1 autoimmune encephalitis manifesting as rapidly progressive dementia and hyponatremia: a case report and literature review. BMC Neurol 2019; 19:19. [PMID: 30732585 PMCID: PMC6366039 DOI: 10.1186/s12883-019-1251-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 02/01/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Anti leucine-rich glioma inactivated 1 (LGI1) encephalitis is a rare autoimmune encephalitis (AE), characterized by acute or subacute cognitive impairment, faciobrachial dystonic seizures, psychiatric disturbances and hyponatremia. Antibody-LGI 1 autoimmune encephalitis (anti-LGI1 AE) has increasingly been recognized as a primary autoimmune disorder with favorable prognosis and response to treatment. CASE PRESENTATION Herein, we reported a male patient presenting as rapidly progressive dementia and hyponatremia. He had antibodies targeting LGI1 both in the cerebrospinal fluid and serum, which demonstrated the diagnosis of typical anti-LGI1 AE. The scores of Mini-Mental State Examination and Montreal Cognitive Assessment were 19/30 and 15/30, respectively. Cranial magnetic resonance images indicated hyperintensities in bilateral hippocampus. The findings of brain arterial spin labeling and Fluorine-18-fluorodeoxyglucose positron emission tomography showed no abnormal perfusion/metabolism. After the combined treatment of intravenous immunoglobulin and glucocorticoid, the patient's clinical symptoms improved obviously. CONCLUSIONS This case raises the awareness that a rapid progressive dementia with predominant memory deficits could be induced by immunoreactions against LGI1. The better recognition will be great importance for the early diagnosis, essential treatment, even a better prognosis.
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Affiliation(s)
- Xuanting Li
- Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, 100020 China
| | - Junliang Yuan
- Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, 100020 China
| | - Lei Liu
- Department of Neurology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730 China
| | - Wenli Hu
- Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, 100020 China
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Shang K, Wang J, Fan X, Cui B, Ma J, Yang H, Zhou Y, Zhao G, Lu J. Clinical Value of Hybrid TOF-PET/MR Imaging-Based Multiparametric Imaging in Localizing Seizure Focus in Patients with MRI-Negative Temporal Lobe Epilepsy. AJNR Am J Neuroradiol 2018; 39:1791-1798. [PMID: 30237304 DOI: 10.3174/ajnr.a5814] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 07/18/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND PURPOSE Temporal lobe epilepsy is the most common type of epilepsy. Early surgical treatment is superior to prolonged medical therapy in refractory temporal lobe epilepsy. Successful surgical operations depend on the correct localization of the epileptogenic zone. This study aimed to evaluate the clinical value of hybrid TOF-PET/MR imaging-based multiparametric imaging in localizing the epileptogenic zone in patients with MR imaging-negative for temporal lobe epilepsy. MATERIALS AND METHODS Twenty patients with MR imaging-negative temporal lobe epilepsy who underwent preoperative evaluation and 10 healthy controls were scanned using PET/MR imaging with simultaneous acquisition of PET and arterial spin-labeling. On the basis of the standardized uptake value and cerebral blood flow, receiver operating characteristic analysis and a logistic regression model were used to evaluate the predictive value for the localization. Statistical analyses were performed using statistical parametric mapping. The values of the standardized uptake value and cerebral blood flow, as well as the asymmetries of metabolism and perfusion, were compared between the 2 groups. Histopathologic findings were used as the criterion standard. RESULTS Complete concordance was noted in lateralization and localization among the PET, arterial spin-labeling, and histopathologic findings in 12/20 patients based on visual assessment. Concordance with histopathologic findings was also obtained for the remaining 8 patients based on the complementary PET and arterial spin-labeling information. Receiver operating characteristic analysis showed that the sensitivity and specificity of PET, arterial spin-labeling, and combined PET and arterial spin-labeling were 100% and 81.8%, 83.3% and 54.5%, and 100% and 90.9%, respectively. When we compared the metabolic abnormalities in patients with those in healthy controls, hypometabolism was detected in the middle temporal gyrus (P < .001). Metabolism and perfusion asymmetries were also located in the temporal lobe (P < .001). CONCLUSIONS PET/MR imaging-based multiparametric imaging involving arterial spin-labeling may increase the clinical value of localizing the epileptogenic zone by providing concordant and complementary information in patients with MR imaging-negative temporal lobe epilepsy.
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Affiliation(s)
- K Shang
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.)
| | - J Wang
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.)
| | - X Fan
- Neurosurgery (X.F., G.Z.)
| | - B Cui
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.)
| | - J Ma
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.)
| | - H Yang
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.)
| | - Y Zhou
- Department of Radiology (Y.Z.), Johns Hopkins University, Baltimore, Maryland
| | - G Zhao
- Neurosurgery (X.F., G.Z.)
| | - J Lu
- From the Departments of Nuclear Medicine (K.S., J.W., B.C., J.M., H.Y., J.L.) .,Radiology (J.L.), Xuanwu Hospital, Capital Medical University, Beijing, China
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Serum NT-pro CNP levels in epileptic seizure, psychogenic non-epileptic seizure, and healthy subjects. Neurol Sci 2018; 39:2135-2139. [PMID: 30232670 DOI: 10.1007/s10072-018-3562-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 09/07/2018] [Indexed: 01/29/2023]
Abstract
PURPOSE Epileptic seizure is the result of uncontrollable neural excitation in the brain. The C-type natriuretic peptide is a member of natriuretic peptide hormone family and is synthesized by brain and blood vessels in CNS. NT-pro CNP is an amino-terminal fragment of C-type natriuretic peptide and is more stable compared to its predecessor. In this study, we aimed to evaluate the role of NT-pro CNP in psychogenic non-epileptic seizures, epileptic seizures, and normal subjects. METHODS Thirty-three patients with epilepsy and 43 patients with psychogenic non-epileptic seizures were enrolled in this study. The control group consisted of 28 healthy subjects. Post-ictal serum levels of NT-pro CNP were acquired from all participants. Statistically significant differences between patient groups and controls regarding serum levels of NT-pro CNP were sought. RESULTS NT-pro CNP levels were significantly lower in the epilepsy group than the psychogenic non-epileptic seizure group and control group with no significant difference between the psychogenic non-epileptic seizure and control group (p < 0.05). CONCLUSION Post-ictal serum NT-pro CNP levels were lower in epileptic seizures compared to psychogenic non-epileptic seizures as well as healthy controls. We think that such a difference is associated with C-type natriuretic peptide-related neural mechanisms such as altered microcirculation, increased brain-blood barrier permeability, and synaptic stabilization.
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Nagesh C, Kumar S, Menon R, Thomas B, Radhakrishnan A, Kesavadas C. The Imaging of Localization Related Symptomatic Epilepsies: The Value of Arterial Spin Labelling Based Magnetic Resonance Perfusion. Korean J Radiol 2018; 19:965-977. [PMID: 30174487 PMCID: PMC6082755 DOI: 10.3348/kjr.2018.19.5.965] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 03/19/2018] [Indexed: 11/15/2022] Open
Abstract
Accurate identification of the epileptogenic zone is an important prerequisite in presurgical evaluation of refractory epilepsy since it affects seizure-free outcomes. Apart from structural magnetic resonance imaging (sMRI), delineation has been traditionally done with electroencephalography and nuclear imaging modalities. Arterial spin labelling (ASL) sequence is a non-contrast magnetic resonance perfusion technique capable of providing similar information. Similar to single-photon emission computed tomography, its utility in epilepsy is based on alterations in perfusion linked to seizure activity by neurovascular coupling. In this article, we discuss complementary value that ASL can provide in the evaluation and characterization of some basic substrates underlying epilepsy. We also discuss the role that ASL may play in sMRI negative epilepsy and acute scenarios such as status epilepticus.
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Affiliation(s)
- Chinmay Nagesh
- Department of Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
| | - Savith Kumar
- Department of Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
| | - Ramshekhar Menon
- Comprehensive Epilepsy Centre, Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
| | - Bejoy Thomas
- Department of Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
| | - Ashalatha Radhakrishnan
- Comprehensive Epilepsy Centre, Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
| | - Chandrasekharan Kesavadas
- Department of Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Trivandrum 695011, India
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27
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Wang YH, An Y, Fan XT, Lu J, Ren LK, Wei PH, Cui BX, Du JL, Lu C, Wang D, Zhang HQ, Shan YZ, Zhao GG. Comparison between simultaneously acquired arterial spin labeling and 18F-FDG PET in mesial temporal lobe epilepsy assisted by a PET/MR system and SEEG. NEUROIMAGE-CLINICAL 2018; 19:824-830. [PMID: 30013926 PMCID: PMC6024198 DOI: 10.1016/j.nicl.2018.06.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 06/02/2018] [Accepted: 06/04/2018] [Indexed: 11/26/2022]
Abstract
Objective In the detection of seizure onset zones, arterial spin labeling (ASL) can overcome the limitations of positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG), which is invasive, expensive, and radioactive. PET/magnetic resonance (MR) systems have been introduced that allow simultaneous performance of ASL and PET, but comparisons of these techniques with stereoelectroencephalography (SEEG) and comparisons among the treatment outcomes of these techniques are still lacking. Here, we investigate the effectiveness of ASL compared with that of SEEG and their outcomes in localizing mesial temporal lobe epilepsy (MTLE) and assess the correlation between simultaneously acquired PET and ASL. Methods Between October 2016 and August 2017, we retrospectively studied 12 patients diagnosed with pure unilateral MTLE. We extracted and quantitatively computed values for ASL and PET in the bilateral hippocampus. SEEG findings and outcome were considered the gold standard of lateralization. Finally, the bilateral asymmetry index (AI) was calculated to assess the correlation between PET and ASL. Results Our results showed that hypoperfusion in the hippocampus detected using ASL matched the SEEG-defined epileptogenic zone in this series of patients. The mean normalized voxel value of ASL in the contralateral hippocampus was 0.97 ± 0.19, while in the ipsilateral hippocampus, it was 0.84 ± 0.14. Meanwhile, significantly decreased perfusion and metabolism were observed in these patients (Wilcoxon, p < 0.05), with a significant positive correlation between the AI values derived from PET and ASL (Pearson's correlation, r = 0.74, p < 0.05). Significance In our SEEG- and outcome-defined patients with MTLE, ASL could provide significant information during presurgical evaluation, with the hypoperfusion detected with ASL reliably lateralizing MTLE. This non-invasive technique may be used as an alternative diagnostic tool for MTLE lateralization. ASL has been increasingly used in presurgical evaluations in epilepsy recent years. Comparisons of ASL and PET with a PET/MR system using SEEG and treatment outcomes as gold-standard are still lacking. Decreased perfusion consistent with hypometabolism and SEEG was observed with ASL. ASL offers an effective non-invasive alternative to PET in evaluation of MTLE.
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Affiliation(s)
- Yi-He Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Yang An
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Xiao-Tong Fan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Jie Lu
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China; Department of Nuclear Medicine, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Lian-Kun Ren
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Peng-Hu Wei
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Bi-Xiao Cui
- Department of Nuclear Medicine, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Jia-Lin Du
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Chao Lu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Di Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Hua-Qiang Zhang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Yong-Zhi Shan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China.
| | - Guo-Guang Zhao
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China; Center of Epilepsy, Beijing Institute for Brain Disorder, Beijing 100069, China.
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Abstract
Electroconvulsive therapy (ECT) is a safe and effective treatment for major depressive disorder, but cerebrovascular and cardiovascular complications, although rare, remain the most concerning. This is particularly notable in those with preexisting cerebrovascular disease, which impacts dynamic cerebral autoregulation. In these patients, the increased blood flow to the seizing portions of the brain induced by ECT potentially can reduce cerebral blood flow to ischemic areas, possibly causing adverse neurological events. The authors describe a patient with chronic cerebral ischemic disease, chronic anemia, and major depressive disorder undergoing ECT to achieve remission. The patient developed recurrent focal neurological deficits after each ECT procedure, with neurological recovery within 48 hours post-ECT. Clinical guidelines may need to be updated for the management of ECT patients with cerebrovascular disease who may be at an increased risk of intraictal and possibly postictal regional ischemia, especially in areas already compromised by a prior stroke and/or by reduced cerebral oxygenation caused by symptomatic anemia at risk of ischemia. Research is needed to assess changes in regional cerebral blood flow during and after ECT in patients with cerebrovascular disease, including small-vessel cerebral ischemia, and to evaluate these changes in relation to the location, intensity, and duration of induced seizure.
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29
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Storti SF, Galazzo IB, Pizzini FB, Menegaz G. Dual-echo ASL based assessment of motor networks: a feasibility study. J Neural Eng 2018; 15:026018. [DOI: 10.1088/1741-2552/aa8b27] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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30
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Gaxiola-Valdez I, Singh S, Perera T, Sandy S, Li E, Federico P. Seizure onset zone localization using postictal hypoperfusion detected by arterial spin labelling MRI. Brain 2017; 140:2895-2911. [PMID: 29053782 DOI: 10.1093/brain/awx241] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 08/03/2017] [Indexed: 11/15/2022] Open
Abstract
Neurological dysfunction following epileptic seizures is a well-recognized phenomenon. Several potential mechanisms have been suggested to explain postictal dysfunction, with alteration in cerebral blood flow being one possibility. These vascular disturbances may be long lasting and localized to brain areas involved in seizure generation and propagation, as supported by both animal and human studies. Therefore, measuring perfusion changes in the postictal period may help localize the seizure onset zone. Arterial spin labelling is a non-invasive, rapid and reproducible magnetic resonance imaging technique that measures cerebral perfusion. To this end, we measured postictal perfusion in patients with drug resistant focal epilepsy who were admitted to our seizure-monitoring unit for presurgical evaluation. Twenty-one patients were prospectively recruited and underwent arterial spin labelling scanning within 90 min of a habitual seizure. Patients also underwent a similar scan in the interictal period, after they were seizure-free for at least 24 h. The acquired scans were subtracted to identify the areas of significant postictal hypoperfusion. The location of the maximal hypoperfusion was compared to the presumed seizure onset zone to assess for concordance. Also, the localizing value of this technique was compared to other structural and functional imaging modalities. Postictal perfusion reductions of >15 units (ml/100 g/l) were seen in 15/21 patients (71.4%). In 12/15 (80%) of these patients, the location of the hypoperfusion was partially or fully concordant with the location of the presumed seizure onset zone. This technique compared favourably to other neuroimaging modalities, being similar or superior to structural magnetic resonance imaging in 52% of cases, ictal single-photon emission computed tomography in 60% of cases and interictal positron emission tomography in 71% of cases. Better arterial spin labelling results were obtained in patients in whom the seizure onset zone was discernible based on non-invasive data. Thus, this technique is a safe, non-invasive and relatively inexpensive tool to detect postictal hypoperfusion that may provide useful data to localize the seizure onset zone. This technique may be incorporated into the battery of conventional investigations for presurgical evaluation of patients with drug resistant focal epilepsy.
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Affiliation(s)
- Ismael Gaxiola-Valdez
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, Canada
| | - Shaily Singh
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Department of Clinical Neurosciences, University of Calgary, Calgary, Canada
| | - Tefani Perera
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, Canada
| | - Sherry Sandy
- Department of Clinical Neurosciences, University of Calgary, Calgary, Canada
| | - Emmy Li
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, Canada.,Department of Neuroscience, University of Calgary, Calgary, Canada
| | - Paolo Federico
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Seaman Family MR Research Centre, University of Calgary, Calgary, Canada.,Department of Clinical Neurosciences, University of Calgary, Calgary, Canada.,Department of Neuroscience, University of Calgary, Calgary, Canada.,Department of Radiology, University of Calgary, Calgary, Canada
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31
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Storti SF, Boscolo Galazzo I, Montemezzi S, Menegaz G, Pizzini FB. Dual-echo ASL contributes to decrypting the link between functional connectivity and cerebral blow flow. Hum Brain Mapp 2017; 38:5831-5844. [PMID: 28885752 DOI: 10.1002/hbm.23804] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 08/23/2017] [Accepted: 08/28/2017] [Indexed: 12/26/2022] Open
Abstract
Arterial spin labeling (ASL) MRI with a dual-echo readout module (DE-ASL) enables noninvasive simultaneous acquisition of cerebral blood flow (CBF)-weighted images and blood oxygenation level dependent (BOLD) contrast. Up to date, resting-state functional connectivity (FC) studies based on CBF fluctuations have been very limited, while the BOLD is still the method most frequently used. The purposes of this technical report were (i) to assess the potentiality of the DE-ASL sequence for the quantification of resting-state FC and brain organization, with respect to the conventional BOLD (cvBOLD) and (ii) to investigate the relationship between a series of complex network measures and the CBF information. Thirteen volunteers were scanned on a 3 T scanner acquiring a pseudocontinuous multislice DE-ASL sequence, from which the concomitant BOLD (ccBOLD) simultaneously to the ASL can be extracted. In the proposed comparison, the brain FC and graph-theoretical analysis were used for quantifying the connectivity strength between pairs of regions and for assessing the network model properties in all the sequences. The main finding was that the ccBOLD part of the DE-ASL sequence provided highly comparable connectivity results compared to cvBOLD. As expected, because of its different nature, ASL sequence showed different patterns of brain connectivity and graph indices compared to BOLD sequences. To conclude, the resting-state FC can be reliably detected using DE-ASL, simultaneously to CBF quantifications, whereas a single fMRI experiment precludes the quantitative measurement of BOLD signal changes. Hum Brain Mapp 38:5831-5844, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Silvia F Storti
- Department of Computer Science, University of Verona, Verona, Italy
| | | | - Stefania Montemezzi
- Department of Diagnostics and Pathology, University Hospital Verona, Verona, Italy
| | - Gloria Menegaz
- Department of Computer Science, University of Verona, Verona, Italy
| | - Francesca B Pizzini
- Department of Diagnostics and Pathology, University Hospital Verona, Verona, Italy
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Identification of cerebral perfusion using arterial spin labeling in patients with seizures in acute settings. PLoS One 2017; 12:e0173538. [PMID: 28291816 PMCID: PMC5349669 DOI: 10.1371/journal.pone.0173538] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 02/21/2017] [Indexed: 11/28/2022] Open
Abstract
This study aimed to explore the utility of arterial spin labeling perfusion-weighted imaging (ASL-PWI) in patients with suspected seizures in acute settings. A total of 164 patients who underwent ASL-PWI for suspected seizures in acute settings (with final diagnoses of seizure [n = 129], poststroke seizure [n = 18], and seizure mimickers [n = 17]), were included in this retrospective study. Perfusion abnormality was analyzed for: (1) pattern, (2) multifocality, and (3) atypical distribution against vascular territories. Perfusion abnormality was detected in 39% (50/129) of the seizure patients, most (94%, 47/50) being the hyperperfusion pattern. Of the patients with perfusion abnormality, multifocality or hemispheric involvement and atypical distribution against vascular territory were revealed in 46% (23/50) and 98% (49/50), respectively. In addition, seizures showed characteristic features including hyperperfusion (with or without non-territorial distribution) on ASL-PWI, thus differentiating them from poststroke seizures or seizure mimickers. In patients in whom seizure focus could be localized on both EEG and ASL-PWI, the concordance rate was 77%. The present study demonstrates that ASL-PWI can provide information regarding cerebral perfusion status in patients with seizures in acute settings and has the potential to be used as a non-invasive imaging tool to identify the cerebral perfusion in patients with seizures.
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Nagesh C, Asranna A, K P D, Cherian A, Nanda S, Thomas B. Culpable brain lesion causing complex partial status in Wilson's disease: Deduction by arterial spin labeled perfusion MRI. Seizure 2017; 46:50-52. [PMID: 28242441 DOI: 10.1016/j.seizure.2017.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 01/15/2017] [Accepted: 02/14/2017] [Indexed: 10/20/2022] Open
Affiliation(s)
- Chinmay Nagesh
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India.
| | - Ajay Asranna
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Divya K P
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Ajith Cherian
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Satyan Nanda
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Bejoy Thomas
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India.
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Cerebral metabolism and perfusion in MR-negative individuals with refractory focal epilepsy assessed by simultaneous acquisition of (18)F-FDG PET and arterial spin labeling. NEUROIMAGE-CLINICAL 2016; 11:648-657. [PMID: 27222796 PMCID: PMC4872676 DOI: 10.1016/j.nicl.2016.04.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 03/24/2016] [Accepted: 04/08/2016] [Indexed: 01/18/2023]
Abstract
The major challenge in pre-surgical epileptic patient evaluation is the correct identification of the seizure onset area, especially in MR-negative patients. In this study, we aimed to: (1) assess the concordance between perfusion, from ASL, and metabolism, from 18F-FDG, acquired simultaneously on PET/MR; (2) verify the utility of a statistical approach as supportive diagnostic tool for clinical readers. Secondarily, we compared 18F-FDG PET data from the hybrid PET/MR system with those acquired with PET/CT, with the purpose of validate the reliability of 18F-FDG PET/MR data. Twenty patients with refractory focal epilepsy, negative MR and a defined electro-clinical diagnosis underwent PET/MR, immediately followed by PET/CT. Standardized uptake value ratio (SUVr) and cerebral blood flow (CBF) maps were calculated for PET/CT-PET/MR and ASL, respectively. For all techniques, z-score of the asymmetry index (zAI) was applied for depicting significant Right/Left differences. SUVr and CBF images were firstly visually assessed by two neuroimaging readers, who then re-assessed them considering zAI for reaching a final diagnosis. High agreement between 18F-FDG PET/MR and ASL was found, showing hypometabolism and hypoperfusion in the same hemisphere in 18/20 patients, while the remaining were normal. They were completely concordant in 14/18, concordant in at least one lobe in the remaining. zAI maps improved readers' confidence in 12/20 and 15/20 patients for 18F-FDG PET/MR and ASL, respectively. 18F-FDG PET/CT-PET/MR showed high agreement, especially when zAI was considered. The simultaneous metabolism-perfusion acquisition provides excellent concordance on focus lateralisation and good concordance on localisation, determining useful complementary information. Simultaneous PET/MR to evaluate cerebral perfusion and glucose metabolism in MR-negative refractory focal epilepsy patients. ASL and 18F-FDG PET/MR showed excellent concordance on lateralisation and good concordance on localisation of focus. ASL and 18F-FDG PET/MR can provide complementary information for focus localisation. An individually-tailored z-score approach can allow a better identification of the epileptic focus.
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35
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Maumet C, Maurel P, Ferré JC, Barillot C. An a contrario approach for the detection of patient-specific brain perfusion abnormalities with arterial spin labelling. Neuroimage 2016; 134:424-433. [PMID: 27039702 DOI: 10.1016/j.neuroimage.2016.03.054] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/16/2016] [Accepted: 03/21/2016] [Indexed: 12/13/2022] Open
Abstract
In this paper, we introduce a new locally multivariate procedure to quantitatively extract voxel-wise patterns of abnormal perfusion in individual patients. This a contrario approach uses a multivariate metric from the computer vision community that is suitable to detect abnormalities even in the presence of closeby hypo- and hyper-perfusions. This method takes into account local information without applying Gaussian smoothing to the data. Furthermore, to improve on the standard a contrario approach, which assumes white noise, we introduce an updated a contrario approach that takes into account the spatial coherency of the noise in the probability estimation. Validation is undertaken on a dataset of 25 patients diagnosed with brain tumours and 61 healthy volunteers. We show how the a contrario approach outperforms the massively univariate general linear model usually employed for this type of analysis.
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Affiliation(s)
- Camille Maumet
- University of Rennes 1, Faculty of Medicine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; INRIA, VisAGeS Project Team, F-35042 Rennes, France; Warwick Manufacturing Group, University of Warwick, CV4 7AL Coventry, United Kingdom.
| | - Pierre Maurel
- University of Rennes 1, Faculty of Medicine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; INRIA, VisAGeS Project Team, F-35042 Rennes, France
| | - Jean-Christophe Ferré
- University of Rennes 1, Faculty of Medicine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; INRIA, VisAGeS Project Team, F-35042 Rennes, France; CHU Rennes, Department of Neuroradiology, F-35033 Rennes, France
| | - Christian Barillot
- University of Rennes 1, Faculty of Medicine, F-35043 Rennes, France; INSERM, U746, F-35042 Rennes, France; CNRS, IRISA, UMR 6074, F-35042 Rennes, France; INRIA, VisAGeS Project Team, F-35042 Rennes, France
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Sierra-Marcos A, Carreño M, Setoain X, López-Rueda A, Aparicio J, Donaire A, Bargalló N. Accuracy of arterial spin labeling magnetic resonance imaging (MRI) perfusion in detecting the epileptogenic zone in patients with drug-resistant neocortical epilepsy: comparison with electrophysiological data, structural MRI, SISCOM and FDG-PET. Eur J Neurol 2015; 23:160-7. [DOI: 10.1111/ene.12826] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/06/2015] [Indexed: 11/28/2022]
Affiliation(s)
| | - M. Carreño
- Institute of Neurosciences; Hospital Clinic; Barcelona Spain
| | - X. Setoain
- Image Diagnosis Center; Hospital Clinic; Barcelona Spain
- Centro de Investigación Biomédica en Red en Bioingeniería; Biomateriales y Nanomedicina (CIBER-BBN); Barcelona Spain
| | - A. López-Rueda
- Image Diagnosis Center; Hospital Clinic; Barcelona Spain
| | - J. Aparicio
- Institute of Neurosciences; Hospital Clinic; Barcelona Spain
| | - A. Donaire
- Institute of Neurosciences; Hospital Clinic; Barcelona Spain
| | - N. Bargalló
- Image Diagnosis Center; Hospital Clinic; Barcelona Spain
- Medical Image Core Facility; August Pi i Sunyer Biomedical Research Institute (IDIBAPS); Barcelona Spain
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Hanby MF, Al-Bachari S, Makin F, Vidyasagar R, Parkes LM, Emsley HCA. Structural and physiological MRI correlates of occult cerebrovascular disease in late-onset epilepsy. NEUROIMAGE-CLINICAL 2015; 9:128-33. [PMID: 26413475 PMCID: PMC4556750 DOI: 10.1016/j.nicl.2015.07.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Late-onset epilepsy (LOE), with onset after 50 years of age, is often attributed to underlying occult cerebrovascular disease. LOE is associated with a three-fold increase in subsequent stroke risk, therefore it is important to improve our understanding of pathophysiology. In this exploratory study, we aimed to determine whether established structural magnetic resonance imaging markers and novel physiological imaging markers of occult cerebrovascular disease were more common in patients with LOE than age-matched controls. Sixteen patients with LOE (mean age ± SD: 67.6 ± 6.5 years) and 15 age-matched control subjects (mean age: 65.1 ± 3.9 years) underwent a 3 T MRI scan protocol. T1-weighted images and T2-weighted fluid attenuated inversion recovery (FLAIR) images were used to determine cortical grey matter volume and white matter hyperintensity (WMH) volume respectively, whilst multiple delay time arterial spin labelling (ASL) images were collected at rest and during a hypercapnic challenge. Cerebral blood flow (CBF) and arterial arrival time (AAT) were calculated from ASL data under both normocapnic and hypercapnic conditions. Cerebrovascular reactivity was also calculated for both CBF and AAT relative to the change in end-tidal CO2. Patients with LOE were found to have significantly lower cortical volume than control subjects (33.8 ± 3.8% of intracranial volume vs. 38.0 ± 5.5%, p = 0.02) and significantly higher WMH volume (1339 ± 1408 mm3 vs. 514 ± 481 mm3, p = 0.047). Baseline whole brain AAT was found to be significantly prolonged in patients with LOE in comparison to control subjects (1539 ± 129 ms vs. 1363 ± 167 ms, p = 0.005). Voxel-based analysis showed the significant prolongation of AAT to be predominantly distributed in the frontal and temporal lobes. Voxel-based morphometry showed the lower cortical volume to be localised primarily to temporal lobes. No significant differences in CBF or cerebrovascular reactivity were found between the two groups. Baseline whole brain AAT and cortical volume differences persisted upon further analysis to take account of differences in smoking history between patients and control subjects. These findings suggest that occult cerebrovascular disease is relevant to the pathophysiology of LOE. LOE patients were found to have increased WMHs and reduced GM volume on MRI imaging in comparison to HC. Baseline arterial arrival time was significantly longer in LOE patients than HC. Baseline cerebral blood flow did not differ between LOE patients and HC. Cerebrovascular reactivity did not differ between LOE patients and HC.
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Key Words
- AAT, arterial arrival time
- ASL, arterial spin labelling
- Arterial spin labelling
- CBF, cerebral blood flow
- CT, computerised tomography
- CVD, cerebrovascular disease
- CVR, cerebrovascular reactivity
- Cerebral blood flow
- Cerebrovascular disease
- EEG, electroencephalogram
- ETCO2, end-tidal CO2
- FLAIR, fluid attenuated inversion recovery image
- FWHM, full width half maximum
- GM, grey matter
- ICV, intracranial volume
- LOE, late-onset epilepsy
- Late-onset epilepsy
- MRI, magnetic resonance imaging
- MoCA, Montreal cognitive assessment
- SVD, small vessel disease
- Seizures
- VBA, voxel-based analysis
- VBM, voxel-based morphometry.
- Voxel-based morphometry
- WMH, white matter hyperintensity
- oCVD, occult cerebrovascular disease
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Affiliation(s)
- Martha F Hanby
- Centre for Imaging Science, Institute of Population Health, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK ; Department of Neurology, Royal Preston Hospital, Preston, UK
| | - Sarah Al-Bachari
- Centre for Imaging Science, Institute of Population Health, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Fadiyah Makin
- Centre for Imaging Science, Institute of Population Health, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Rishma Vidyasagar
- Centre for Imaging Science, Institute of Population Health, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Laura M Parkes
- Centre for Imaging Science, Institute of Population Health, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | - Hedley C A Emsley
- Department of Neurology, Royal Preston Hospital, Preston, UK ; Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
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