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Heholt J, Patel R, Vedaei F, Zabrecky G, Wintering N, Monti DA, Wang Z, Newberg AB, Mohamed FB. Simultaneous arterial spin labeling functional MRI and fluorodeoxyglucose PET in mild chronic traumatic brain injury. J Neuroradiol 2024; 51:101211. [PMID: 38908545 DOI: 10.1016/j.neurad.2024.101211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 06/12/2024] [Accepted: 06/18/2024] [Indexed: 06/24/2024]
Abstract
BACKGROUND AND PURPOSE To determine the effect of mild chronic traumatic brain injury (cTBI) on cerebral blood flow and metabolism. METHODS 62 cTBI and 40 healthy controls (HCs) with no prior history of cTBI underwent both pulsed arterial spin labeling functional magnetic resonance imaging (PASL-fMRI) and fluorodeoxyglucose positron emission tomography (FDG-PET) scanning via a Siemens mMR (simultaneous PET/MRI) scanner. 30 participants also took part in a series of neuropsychological clinical measures (NCMs). Images were processed using statistical parametric mapping software relevant to each modality to generate relative cerebral blood flow (rCBF) and glucose metabolic standardized uptake value ratio (gSUVR) grey matter maps. A voxel-wise two-sample T-test and two-tailed gaussian random field correction for multiple comparisons was performed. RESULTS cTBI patients showed a significant increase in rCBF and gSUVR in the right thalamus as well as a decrease in bilateral occipital lobes and calcarine sulci. An inverse relationship between rCBF and gSUVR was found in the left frontal lobe, the left precuneus and regions in the right temporal lobe. Within those regions rCBF values correlated with 9 distinct NCMs and gSUVR with 3. CONCLUSION Simultaneous PASL-fMRI and FDG-PET can identify functional changes in a mild cTBI population. Within this population FDG-PET identified more regions of functional disturbance than ASL fMRI and NCMs are shown to correlate with rCBF and glucose metabolism (gSUVR) in various brain regions. As a result, both imaging modalities contribute to understanding the underlying pathophysiology and clinical course of mild chronic traumatic brain injury.
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Affiliation(s)
- Justin Heholt
- Department of Radiology, State University of New York, Downstate Medical Center, Brooklyn, NY, USA
| | - Riya Patel
- Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Faezeh Vedaei
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - George Zabrecky
- Department of Integrative Medicine and Nutritional Sciences, Marcus Institute of Integrative Health, Thomas Jefferson University, Philadelphia, PA, USA
| | - Nancy Wintering
- Department of Integrative Medicine and Nutritional Sciences, Marcus Institute of Integrative Health, Thomas Jefferson University, Philadelphia, PA, USA
| | - Daniel A Monti
- Department of Integrative Medicine and Nutritional Sciences, Marcus Institute of Integrative Health, Thomas Jefferson University, Philadelphia, PA, USA
| | - Ze Wang
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine
| | - Andrew B Newberg
- Department of Integrative Medicine and Nutritional Sciences, Marcus Institute of Integrative Health, Thomas Jefferson University, Philadelphia, PA, USA.
| | - Feroze B Mohamed
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
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Gennari AG, Bicciato G, Lo Biundo SP, Kottke R, Stefanos-Yakoub I, Cserpan D, O'Gorman Tuura R, Ramantani G. Lesion volume and spike frequency on EEG impact perfusion values in focal cortical dysplasia: a pediatric arterial spin labeling study. Sci Rep 2024; 14:7601. [PMID: 38556543 PMCID: PMC10982306 DOI: 10.1038/s41598-024-58352-9] [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: 11/13/2023] [Accepted: 03/28/2024] [Indexed: 04/02/2024] Open
Abstract
Arterial spin labelling (ASL), an MRI sequence non-invasively imaging brain perfusion, has yielded promising results in the presurgical workup of children with focal cortical dysplasia (FCD)-related epilepsy. However, the interpretation of ASL-derived perfusion patterns remains unclear. Hence, we compared ASL qualitative and quantitative findings to their clinical, EEG, and MRI counterparts. We included children with focal structural epilepsy related to an MRI-detectable FCD who underwent single delay pseudo-continuous ASL. ASL perfusion changes were assessed qualitatively by visual inspection and quantitatively by estimating the asymmetry index (AI). We considered 18 scans from 15 children. 16 of 18 (89%) scans showed FCD-related perfusion changes: 10 were hypoperfused, whereas six were hyperperfused. Nine scans had perfusion changes larger than and seven equal to the FCD extent on anatomical images. Hyperperfusion was associated with frequent interictal spikes on EEG (p = 0.047). Perfusion changes in ASL larger than the FCD corresponded to larger lesions (p = 0.017). Higher AI values were determined by frequent interictal spikes on EEG (p = 0.004). ASL showed FCD-related perfusion changes in most cases. Further, higher spike frequency on EEG may increase ASL changes in affected children. These observations may facilitate the interpretation of ASL findings, improving treatment management, counselling, and prognostication in children with FCD-related epilepsy.
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Affiliation(s)
- Antonio Giulio Gennari
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland
- MR-Research Centre, University Children's Hospital Zurich, Zurich, Switzerland
| | - Giulio Bicciato
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland
- Department of Neurology, University Hospital Zurich, Zurich, Switzerland
| | - Santo Pietro Lo Biundo
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland
| | - Raimund Kottke
- Department of Radiology, University Children's Hospital Zurich, Zurich, Switzerland
| | - Ilona Stefanos-Yakoub
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland
| | - Dorottya Cserpan
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland
| | - Ruth O'Gorman Tuura
- MR-Research Centre, University Children's Hospital Zurich, Zurich, Switzerland
- University of Zurich, Zurich, Switzerland
- Children's Research Centre, University Children's Hospital Zurich, Zurich, Switzerland
| | - Georgia Ramantani
- Department of Neuropediatrics, University Children's Hospital Zurich, 75, 8032, Zurich, Switzerland.
- University of Zurich, Zurich, Switzerland.
- Children's Research Centre, University Children's Hospital Zurich, Zurich, Switzerland.
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van de Velden D, Heide EC, Bouter C, Bucerius J, Riedel CH, Focke NK. Effects of inverse methods and spike phases on interictal high-density EEG source reconstruction. Clin Neurophysiol 2023; 156:4-13. [PMID: 37832322 DOI: 10.1016/j.clinph.2023.08.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 08/15/2023] [Accepted: 08/24/2023] [Indexed: 10/15/2023]
Abstract
OBJECTIVE To determine the effect of inverse methods and timepoints of interictal epileptic discharges (IEDs) used for high-density electric source imaging (hd-ESI) in pharmacoresistant focal epilepsies. METHODS We retrospectively evaluated the hd-ESI and [18F]fluorodeoxyglucose positron emission tomography (18FDG-PET) of 21 operated patients with pharmacoresistant focal epilepsy (Engel I). Volumetric hd-ESI was performed with three different inverse methods such as the inverse solution linearly constrained minimum variance (LCMV, a beamformer method), standardized low resolution electromagnetic tomography (sLORETA) and weighted minimum-norm estimation (wMNE) and at different IED phases. Hd-ESI accuracy was determined by volumetric overlap and distance between hd-ESI source maximum, as well as 18FDG-PET hypometabolic region relative to the resection zone (RZ). RESULTS In our cohort, the shortest distances and greatest volumetric overlaps to the RZ were found in the half-rise and peak-phase for all inverse methods. The distance to the RZ was not different between the centroid of the clinical hypothesis-based cluster and the source maximum in peak-phase. However, the distance of the hypothesis-based cluster was significantly shorter compared to the cluster selected by the smallest p-value. CONCLUSIONS Hd-ESI provides the greatest accuracy in determining the RZ at the IED half-rise and peak-phase for all applied inverse methods, whereby sLORETA and LCMV were equally accurate. SIGNIFICANCE Our results offer guidance in selecting inverse methods and IED phases for hd-ESI, compare the performance of hd-ESI and 18FDG-PET and encourage future studies in investigating the relationship between interictal ESI and 18FDG-PET hypometabolism.
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Affiliation(s)
- Daniel van de Velden
- University Medical Center Göttingen, Clinic for Neurology, 37075 Göttingen, Germany.
| | - Ev-Christin Heide
- University Medical Center Göttingen, Clinic for Neurology, 37075 Göttingen, Germany
| | - Caroline Bouter
- University Medical Center Göttingen, Department of Nuclear Medicine, 37075 Göttingen, Germany
| | - Jan Bucerius
- University Medical Center Göttingen, Department of Nuclear Medicine, 37075 Göttingen, Germany
| | - Christian H Riedel
- University Medical Center Göttingen, Institute for Diagnostic and Interventional Neuroradiology, 37075 Göttingen, Germany
| | - Niels K Focke
- University Medical Center Göttingen, Clinic for Neurology, 37075 Göttingen, Germany.
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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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Rahimzadeh H, Kamkar H, Hoseini-Tabatabaei N, Mobarakeh NM, Habibabadi JM, Hashemi-Fesharaki SS, Nazem-Zadeh MR. Alteration of intracranial blood perfusion in temporal lobe epilepsy, an arterial spin labeling study. Heliyon 2023; 9:e14854. [PMID: 37089370 PMCID: PMC10119575 DOI: 10.1016/j.heliyon.2023.e14854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 03/19/2023] [Accepted: 03/20/2023] [Indexed: 04/25/2023] Open
Abstract
Background A critical necessity before surgical resection in mesial temporal lobe epilepsy (mTLE) is lateralizing the seizure focus in the temporal lobe. This study aimed to investigate the differences in perfusion pattern changes in right and left mTLE. Methods 42 mTLE patients (22 left and 20 right mTLE) and 14 controls were surveyed with pulsed arterial spin labeling at 3.0 T. The mean cerebral blood flow (CBF) and asymmetry index (AI) were calculated in the bilateral temporal lobe, amygdala, hippocampus, parahippocampus, and nine bilateral vascular territories ROIs. The alterations in whole-brain CBF were identified using statistical parametric mapping (SPM). Results CBF decreased in ipsilateral sides in both epilepsy subcohorts, with right mTLE showing a significant difference in most ROIs while left mTLE exhibiting no significant change. CBF comparison of left mTLE and controls showed a significant drop in ROI analysis in left middle temporal and left intermediate posterior cerebral artery and in AI analysis in parahippocampus, distal anterior cerebral artery, distal middle cerebral artery, and intermediate anterior cerebral artery. CBF hypoperfusion was seen in ROI analysis in the left intermediate anterior cerebral artery, left middle temporal, right middle temporal, left superior temporal in the right mTLE compared to controls. Left mTLE CBF differed significantly from right mTLE CBF in right distal middle cerebral artery ROI and AI of proximal middle cerebral artery. Conclusion Our result revealed that mTLE affects extratemporal regions and both mTLE subcohorts with different perfusion patterns, which may enhance the performance of preoperative MRI assessment in lateralization procedures.
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Affiliation(s)
- Hossein Rahimzadeh
- Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Equipment Institute (AMTEI), Tehran University of Medical Sciences, Tehran, Iran
- Department of Biomedical Engineering and Medical Physics, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hadi Kamkar
- Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Equipment Institute (AMTEI), Tehran University of Medical Sciences, Tehran, Iran
- Bioinformatics and Biophysics Department, Tarbiat Modares University, Tehran, Iran
| | | | - Neda Mohammadi Mobarakeh
- Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Equipment Institute (AMTEI), Tehran University of Medical Sciences, Tehran, Iran
- Medical Physics and Biomedical Engineering Department, Tehran University of Medical Sciences, Tehran, Iran
| | | | | | - Mohammad-Reza Nazem-Zadeh
- Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Equipment Institute (AMTEI), Tehran University of Medical Sciences, Tehran, Iran
- Medical Physics and Biomedical Engineering Department, Tehran University of Medical Sciences, Tehran, Iran
- Department of Neuroscience, Monash University, Melbourne, Australia
- Corresponding author.Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Equipment Institute (AMTEI), Tehran University of Medical Sciences, Tehran, Iran.
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Chen G, Hu J, Ran H, Nie L, Tang W, Li X, Li Q, He Y, Liu J, Song G, Xu G, Liu H, Zhang T. Alterations of Cerebral Perfusion and Functional Connectivity in Children With Idiopathic Generalized Epilepsy. Front Neurosci 2022; 16:918513. [PMID: 35769697 PMCID: PMC9236200 DOI: 10.3389/fnins.2022.918513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/25/2022] [Indexed: 12/02/2022] Open
Abstract
Background Studies have demonstrated that adults with idiopathic generalized epilepsy (IGE) have functional abnormalities; however, the neuropathological pathogenesis differs between adults and children. This study aimed to explore alterations in the cerebral blood flow (CBF) and functional connectivity (FC) to comprehensively elucidate the neuropathological mechanisms of IGE in children. Methods We obtained arterial spin labeling (ASL) and resting state functional magnetic resonance imaging data of 28 children with IGE and 35 matched controls. We used ASL to determine differential CBF regions in children with IGE. A seed-based whole-brain FC analysis was performed for regions with significant CBF changes. The mean CBF and FC of brain areas with significant group differences was extracted, then its correlation with clinical variables in IGE group was analyzed by using Pearson correlation analysis. Results Compared to controls, children with IGE had CBF abnormalities that were mainly observed in the right middle temporal gyrus, right middle occipital gyrus (MOG), right superior frontal gyrus (SFG), left inferior frontal gyrus (IFG), and triangular part of the left IFG (IFGtriang). We observed that the FC between the left IFGtriang and calcarine fissure (CAL) and that between the right MOG and bilateral CAL were decreased in children with IGE. The CBF in the right SFG was correlated with the age at IGE onset. FC in the left IFGtriang and left CAL was correlated with the IGE duration. Conclusion This study found that CBF and FC were altered simultaneously in the left IFGtriang and right MOG of children with IGE. The combination of CBF and FC may provide additional information and insight regarding the pathophysiology of IGE from neuronal and vascular integration perspectives.
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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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Khalaf A, Nadel H, Dahmoush H. Simultaneously Acquired MRI Arterial Spin-Labeling and Interictal FDG-PET Improves Diagnosis of Pediatric Temporal Lobe Epilepsy. AJNR Am J Neuroradiol 2022; 43:468-473. [PMID: 35210273 PMCID: PMC8910808 DOI: 10.3174/ajnr.a7421] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 12/06/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Interictal FDG-PET scans are a routine diagnostic technique for the identification of epileptogenic foci in the presurgical work-up of medically refractory pediatric epilepsy. With the advent of PET/MR imaging, it has become possible to simultaneously acquire FDG-PET and arterial spin-labeling perfusion data. The objective of this study was to evaluate whether the incorporation of arterial spin-labeling data with interictal FDG-PET could improve the diagnostic performance metrics of FDG-PET for identification of epileptogenic foci. MATERIALS AND METHODS Forty-five pediatric patients with a mean age of 10.8 years were retrospectively included in this study. These patients all underwent PET/MR imaging to diagnose suspected focal epilepsy. RESULTS When compared to interpretations of interictal FDG findings alone, FDG combined with arterial spin-labeling findings resulted in significantly decreased sensitivity (0.64 versus 0.52, P = .02), significantly increased specificity (0.50 versus 0.75, P = .04), and an increased positive predictive value (0.59 versus 0.75). The decreased sensitivity was found to be primarily driven by patients with extratemporal lobe epilepsy, as a subgroup analysis showed decreased sensitivity for patients with extratemporal epilepsy (0.52 versus 0.38, P = .04), but not for temporal epilepsy (0.83 versus 0.75, P = .16). Additionally, substantial agreement between focal FDG hypometabolism and arterial spin-labeling hypoperfusion was demonstrated with the Cohen κ (0.70, P < .01). CONCLUSIONS These findings suggest that simultaneously acquired interictal FDG-PET and arterial spin-labeling data can improve the diagnosis of epileptogenic foci, especially in the setting of temporal lobe epilepsy where they improve specificity and positive predictive value, with preservation of sensitivity.
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Affiliation(s)
- A.M. Khalaf
- From the Stanford University School of Medicine, Department of Radiology, Division of Nuclear Medicine & Molecular Imaging, Division of Pediatric Radiology, Division of Neuroimaging & Neurointervention, Stanford University, Stanford, California
| | - H.R. Nadel
- From the Stanford University School of Medicine, Department of Radiology, Division of Nuclear Medicine & Molecular Imaging, Division of Pediatric Radiology, Division of Neuroimaging & Neurointervention, Stanford University, Stanford, California
| | - H.M. Dahmoush
- From the Stanford University School of Medicine, Department of Radiology, Division of Nuclear Medicine & Molecular Imaging, Division of Pediatric Radiology, Division of Neuroimaging & Neurointervention, Stanford University, Stanford, California
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Mittal A, Singh Dhanota DP, Saggar K, Singh G, Ahluwalia A. Role of Interictal Arterial Spin Labeling Magnetic Resonance Perfusion in Mesial Temporal Lobe Epilepsy. Ann Indian Acad Neurol 2021; 24:495-500. [PMID: 34728940 PMCID: PMC8513983 DOI: 10.4103/aian.aian_1274_20] [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: 12/18/2020] [Revised: 01/31/2021] [Accepted: 04/14/2021] [Indexed: 11/18/2022] Open
Abstract
Context: Electrophysiological and hemodynamic data can be integrated to accurately identify the generators of abnormal electrical activity in drug-resistant focal epilepsy. Arterial Spin Labeling (ASL), a magnetic resonance imaging (MRI) technique for quantitative noninvasive measurement of cerebral blood flow (CBF), can provide a direct measure of variations in cerebral perfusion associated with the epileptogenic zone. Aims: 1. To evaluate usefulness of ASL for detecting interictal temporal hypoperfusion to localize the epileptogenic zone in patients of drug resistant mesial temporal lobe epilepsy (MTLE). 2. Correlation of localization of epileptogenic zone on ASL MR perfusion with structural MRI and EEG. Methods and Materials: 30 patients with MTLE and10 age and gender matched normal controls were studied. All patients underwent ictal video EEG monitoring non-invasively, MR imaging with epilepsy protocol and pseudocontinuous ASL (PCASL) perfusion study. Relative CBF (rCBF) values in bilateral mesial temporal lobes were measured utilizing quantitative analysis of perfusion images. A perfusion asymmetry index (AI) was calculated for each region. Results: In patients, ipsilateral mesial temporal rCBF was significantly decreased compared with contralateral mesial temporal rCBF (p = 0.021). Mesial temporal blood flow was more asymmetric in patients than in normal control participants (p = 0.000). Clear perfusion asymmetry on PCASL-MRI was identified despite normal structural-MRI in 5 cases, agreeing with EEG laterality. Conclusions: Pseudo-continuous ASL offers a promising approach to detect interictal hypoperfusion in TLE and as a clinical alternative to SPECT and PET due to non-invasiveness and easy accessibility. Incorporation of ASL into routine pre-surgical evaluation protocols can help to localize epileptogenic zone in surgical candidates.
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Affiliation(s)
- Ashima Mittal
- Department of Radiodiagnosis and Imaging, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Devinder Pal Singh Dhanota
- Department of Radiodiagnosis and Imaging, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Kavita Saggar
- Department of Radiodiagnosis and Imaging, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Gagandeep Singh
- Department of Neurology, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Archana Ahluwalia
- Department of Radiodiagnosis and Imaging, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
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11
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Pasca L, Sanvito F, Ballante E, Totaro M, Paoletti M, Bergui A, Varesio C, Rognone E, De Giorgis V, Pichiecchio A. Arterial spin labelling qualitative assessment in paediatric patients with MRI-negative epilepsy. Clin Radiol 2021; 76:942.e15-942.e23. [PMID: 34645570 DOI: 10.1016/j.crad.2021.09.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 09/10/2021] [Indexed: 11/29/2022]
Abstract
AIM To evaluate the usefulness of arterial spin labelling (ASL) qualitative analysis for the localisation of seizure-related perfusion abnormalities in paediatric patients with negative brain magnetic resonance imaging (MRI) epilepsy. MATERIALS AND METHODS Forty-two patients with a diagnosis of MRI-negative focal or generalised epilepsy, who underwent electroencephalogram (EEG) and MRI with ASL in the interictal phase were included. Perfusion abnormalities were evaluated through a qualitative assessment and then compared to EEG seizure focus. RESULTS Among the 42 patients, 26 had focal epilepsy and 16 had generalised epilepsy. Thirty-three patients (79%) showed a perfusion abnormality, mainly hypoperfusion (74.5% of all ASL alterations), whereas hyperperfused alterations were more represented in patients who experienced the last seizure either less than 48 hours prior to ASL acquisition or in the time interval from 1 week to 1 month prior to ASL acquisition (p=0.034). Concordance of ASL abnormality and EEG focus was found in 33 patients (78.5%), as complete in 17 (40.5%) and as partial in 16 (38%). A trend of higher concordance was found in focal epilepsies compared to generalised epilepsies (p=0.059). The concordance between ASL and EEG major alterations was higher for hyperperfused anomalies than for hypoperfused ones (p=0.009). Variables such as age, sedation, and time from last seizure were not significant contributors for concordance. CONCLUSIONS The combined use of qualitative ASL and brain MRI and scalp EEG could be a potential tool in daily clinical practice.
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Affiliation(s)
- L Pasca
- Department of Child Neurology and Psychiatry, IRCSS Mondino Foundation, Pavia, Italy; Department of Brain and Behaviour Neuroscience, University of Pavia, Pavia, Italy
| | - F Sanvito
- Unit of Radiology, Department of Clinical, Surgical, Diagnostic, and Paediatric Sciences, University of Pavia, Pavia, Italy
| | - E Ballante
- Department of Mathematics, University of Pavia, Pavia, Italy; BioData Science Center, IRCCS Mondino Foundation, Pavia, Italy
| | - M Totaro
- Department of Child Neurology and Psychiatry, IRCSS Mondino Foundation, Pavia, Italy; Department of Brain and Behaviour Neuroscience, University of Pavia, Pavia, Italy
| | - M Paoletti
- Advanced Imaging and Radiomics, Department of Neuroradiology, IRCCS Mondino Foundation, Pavia, Italy
| | - A Bergui
- Unit of Radiology, Department of Clinical, Surgical, Diagnostic, and Paediatric Sciences, University of Pavia, Pavia, Italy
| | - C Varesio
- Department of Child Neurology and Psychiatry, IRCSS Mondino Foundation, Pavia, Italy
| | - E Rognone
- Advanced Imaging and Radiomics, Department of Neuroradiology, IRCCS Mondino Foundation, Pavia, Italy
| | - V De Giorgis
- Department of Child Neurology and Psychiatry, IRCSS Mondino Foundation, Pavia, Italy.
| | - A Pichiecchio
- Department of Brain and Behaviour Neuroscience, University of Pavia, Pavia, Italy; Advanced Imaging and Radiomics, Department of Neuroradiology, IRCCS Mondino Foundation, Pavia, Italy
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12
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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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13
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Pellerin A, Khalifé M, Sanson M, Rozenblum-Beddok L, Bertaux M, Soret M, Galanaud D, Dormont D, Kas A, Pyatigorskaya N. Simultaneously acquired PET and ASL imaging biomarkers may be helpful in differentiating progression from pseudo-progression in treated gliomas. Eur Radiol 2021; 31:7395-7405. [PMID: 33787971 DOI: 10.1007/s00330-021-07732-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/21/2020] [Accepted: 01/29/2021] [Indexed: 12/21/2022]
Abstract
OBJECTIVES The aim of this work was investigating the methods based on coupling cerebral perfusion (ASL) and amino acid metabolism ([18F]DOPA-PET) measurements to evaluate the diagnostic performance of PET/MRI in glioma follow-up. METHODS Images were acquired using a 3-T PET/MR system, on a prospective cohort of patients addressed for possible glioma progression. Data were preprocessed with statistical parametric mapping (SPM), including registration on T1-weighted images, spatial and intensity normalization, and tumor segmentation. As index tests, tumor isocontour maps of [18F]DOPA-PET and ASL T-maps were created and metabolic/perfusion abnormalities were evaluated with the asymmetry index z-score. SPM map analysis of significant size clusters and semi-quantitative PET and ASL map evaluation were performed and compared to the gold standard diagnosis. Lastly, ASL and PET topography of significant clusters was compared to that of the initial tumor. RESULTS Fifty-eight patients with unilateral treated glioma were included (34 progressions and 24 pseudo-progressions). The tumor isocontour maps and T-maps showed the highest specificity (100%) and sensitivity (94.1%) for ASL and [18F]DOPA analysis, respectively. The sensitivity of qualitative SPM maps and semi-quantitative rCBF and rSUV analyses were the highest for glioblastoma. CONCLUSION Tumor isocontour T-maps and combined analysis of CBF and [18F]DOPA-PET uptake allow achieving high diagnostic performance in differentiating between progression and pseudo-progression in treated gliomas. The sensitivity is particularly high for glioblastomas. KEY POINTS • Applied separately, MRI and PET imaging modalities may be insufficient to characterize the brain glioma post-therapeutic profile. • Combined ASL and [18F]DOPA-PET map analysis allows differentiating between tumor progression and pseudo-progression.
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Affiliation(s)
- Arnaud Pellerin
- Service de Neuroradiologie Diagnostique et Interventionnelle, Centre Hospitalier Universitaire de Nantes, Hôpital Nord Laennec, Rez-de-chaussée Bas Aile Est, Boulevard Jacques-Monod, Saint-Herblain, 44093, Nantes Cedex 1, France.
- Service de Neuroradiologie Diagnostique et Fonctionnelle, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France.
| | - Maya Khalifé
- Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225 - Inserm U1127 - Sorbonne Université - UMR S1127, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
- Arterys, 34 av. des Champs-Elysées, 75008, Paris, France
| | - Marc Sanson
- Service de Neurologie, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Laura Rozenblum-Beddok
- Service de Médecine Nucléaire, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Marc Bertaux
- Service de Médecine Nucléaire, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Marine Soret
- Service de Médecine Nucléaire, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Damien Galanaud
- Service de Neuroradiologie Diagnostique et Fonctionnelle, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
- Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225 - Inserm U1127 - Sorbonne Université - UMR S1127, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Didier Dormont
- Service de Neuroradiologie Diagnostique et Fonctionnelle, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
| | - Aurélie Kas
- Service de Médecine Nucléaire, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
- Université Paris 6 UPMC, LIB Inserm U1146, 91-105 Boulevard de l'Hôpital, 75013, Paris, France
| | - Nadya Pyatigorskaya
- Service de Neuroradiologie Diagnostique et Fonctionnelle, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
- Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225 - Inserm U1127 - Sorbonne Université - UMR S1127, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France
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14
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Stoyell SM, Wilmskoetter J, Dobrota MA, Chinappen DM, Bonilha L, Mintz M, Brinkmann BH, Herman ST, Peters JM, Vulliemoz S, Seeck M, Hämäläinen MS, Chu CJ. High-Density EEG in Current Clinical Practice and Opportunities for the Future. J Clin Neurophysiol 2021; 38:112-123. [PMID: 33661787 PMCID: PMC8083969 DOI: 10.1097/wnp.0000000000000807] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
SUMMARY High-density EEG (HD-EEG) recordings use a higher spatial sampling of scalp electrodes than a standard 10-20 low-density EEG montage. Although several studies have demonstrated improved localization of the epileptogenic cortex using HD-EEG, widespread implementation is impeded by cost, setup and interpretation time, and lack of specific or sufficient procedural billing codes. Despite these barriers, HD-EEG has been in use at several institutions for years. These centers have noted utility in a variety of clinical scenarios where increased spatial resolution from HD-EEG has been required, justifying the extra time and cost. We share select scenarios from several centers, using different recording techniques and software, where HD-EEG provided information above and beyond the standard low-density EEG. We include seven cases where HD-EEG contributed directly to current clinical care of epilepsy patients and highlight two novel techniques which suggest potential opportunities to improve future clinical care. Cases illustrate how HD-EEG allows clinicians to: case 1-lateralize falsely generalized interictal epileptiform discharges; case 2-improve localization of falsely generalized epileptic spasms; cases 3 and 4-improve localization of interictal epileptiform discharges in anatomic regions below the circumferential limit of standard low-density EEG coverage; case 5-improve noninvasive localization of the seizure onset zone in lesional epilepsy; cases 6 and 7-improve localization of the seizure onset zone to guide invasive investigation near eloquent cortex; case 8-identify epileptic fast oscillations; and case 9-map language cortex. Together, these nine cases illustrate that using both visual analysis and advanced techniques, HD-EEG can play an important role in clinical management.
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Affiliation(s)
- Sally M Stoyell
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, U.S.A
| | - Janina Wilmskoetter
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina, U.S.A
| | - Mary-Ann Dobrota
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, U.S.A
| | | | - Leonardo Bonilha
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina, U.S.A
| | - Mark Mintz
- The Center for Neurological and Neurodevelopmental Health, Voorhees, New Jersey, U.S.A
| | | | - Susan T Herman
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, U.S.A
| | - Jurriaan M Peters
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, U.S.A
| | - Serge Vulliemoz
- EEG and Epilepsy Unit, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Margitta Seeck
- EEG and Epilepsy Unit, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Matti S Hämäläinen
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, U.S.A
- Harvard Medical School, Boston, Massachusetts, U.S.A
| | - Catherine J Chu
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, U.S.A
- Harvard Medical School, Boston, Massachusetts, U.S.A
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15
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Höller Y, Nardone R. Quantitative EEG biomarkers for epilepsy and their relation to chemical biomarkers. Adv Clin Chem 2020; 102:271-336. [PMID: 34044912 DOI: 10.1016/bs.acc.2020.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The electroencephalogram (EEG) is the most important method to diagnose epilepsy. In clinical settings, it is evaluated by experts who identify patterns visually. Quantitative EEG is the application of digital signal processing to clinical recordings in order to automatize diagnostic procedures, and to make patterns visible that are hidden to the human eye. The EEG is related to chemical biomarkers, as electrical activity is based on chemical signals. The most well-known chemical biomarkers are blood laboratory tests to identify seizures after they have happened. However, research on chemical biomarkers is much less extensive than research on quantitative EEG, and combined studies are rarely published, but highly warranted. Quantitative EEG is as old as the EEG itself, but still, the methods are not yet standard in clinical practice. The most evident application is an automation of manual work, but also a quantitative description and localization of interictal epileptiform events as well as seizures can reveal important hints for diagnosis and contribute to presurgical evaluation. In addition, the assessment of network characteristics and entropy measures were found to reveal important insights into epileptic brain activity. Application scenarios of quantitative EEG in epilepsy include seizure prediction, pharmaco-EEG, treatment monitoring, evaluation of cognition, and neurofeedback. The main challenges to quantitative EEG are poor reliability and poor generalizability of measures, as well as the need for individualization of procedures. A main hindrance for quantitative EEG to enter clinical routine is also that training is not yet part of standard curricula for clinical neurophysiologists.
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Affiliation(s)
- Yvonne Höller
- Faculty of Psychology, University of Akureyri, Akureyri, Iceland.
| | - Raffaele Nardone
- Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Spinal Cord Injury and Tissue Regeneration Center, Salzburg, Austria; Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria
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16
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Soldozy S, Galindo J, Snyder H, Ali Y, Norat P, Yağmurlu K, Sokolowski JD, Sharifi K, Tvrdik P, Park MS, Kalani MYS. Clinical utility of arterial spin labeling imaging in disorders of the nervous system. Neurosurg Focus 2020; 47:E5. [PMID: 31786550 DOI: 10.3171/2019.9.focus19567] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 09/16/2019] [Indexed: 11/06/2022]
Abstract
Neuroimaging is an indispensable tool in the workup and management of patients with neurological disorders. Arterial spin labeling (ASL) is an imaging modality that permits the examination of blood flow and perfusion without the need for contrast injection. Noninvasive in nature, ASL provides a feasible alternative to existing vascular imaging techniques, including angiography and perfusion imaging. While promising, ASL has yet to be fully incorporated into the diagnosis and management of neurological disorders. This article presents a review of the most recent literature on ASL, with a special focus on its use in moyamoya disease, brain neoplasms, seizures, and migraines and a commentary on recent advances in ASL that make the imaging technique more attractive as a clinically useful tool.
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17
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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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18
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Abstract
Purpose of review Imaging constitutes one of the key pillars in the diagnostic workup after a first seizure as well as for the presurgical workup in epilepsy. The role of imaging in emergency situations, mainly to support the adequate diagnosis, as well as its role in planning of noninvasive image-guided therapies is less well established. Here, we provide an overview on peri-ictal imaging findings to support differential diagnosis in emergency situations and describe recent attempts toward minimal invasive therapy in the treatment of epilepsy and its comorbidities based on a combination of imaging techniques with ultrasound. Recent findings Peri-ictal perfusion changes can differentiate ictal stroke mimics from acute ischemic stroke if focal areas of increased perfusion are depicted by computed tomography or MRI. Postictal perfusion patterns in patients with persisting neurological symptoms are frequently normal and do not reach enough diagnostic sensitivity to differentiate between stroke and its mimics. Noninvasive magnetic resonance-techniques as arterial spin labeling may provide a higher sensitivity, especially in combination with diffusion-weighted and susceptibility-weighted MRI. Imaging guided focused ultrasound (FUS) bears the potential to ablate epileptogenic tissue and allows suppression of epileptic activity. Imaging guided blood–brain-barrier opening with FUS offers new options for local drug administration. Summary MRI should be considered the method of choice in the differential diagnosis of peri-ictal imaging findings and their differential diagnosis. A combination of various MRI techniques with FUS opens new avenues for treatment of epilepsy.
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19
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Abstract
Candidates for epilepsy surgery must undergo presurgical evaluation to establish whether and how surgical treatment can stop seizures without causing neurological deficits. Various techniques, including MRI, PET, single-photon emission CT, video-EEG, magnetoencephalography and invasive EEG, aim to identify the diseased brain tissue and the involved network. Recent technical and methodological developments, encompassing both advances in existing techniques and new combinations of technologies, are enhancing the ability to define the optimal resection strategy. Multimodal interpretation and predictive computer models are expected to aid surgical planning and patient counselling, and multimodal intraoperative guidance is likely to increase surgical precision. In this Review, we discuss how the knowledge derived from these new approaches is challenging our way of thinking about surgery to stop focal seizures. In particular, we highlight the importance of looking beyond the EEG seizure onset zone and considering focal epilepsy as a brain network disease in which long-range connections need to be taken into account. We also explore how new diagnostic techniques are revealing essential information in the brain that was previously hidden from view.
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20
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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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21
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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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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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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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Polyanskaya MV, Demushkina AA, Vasiliev IG, Gazdieva HS, Kholin AA, Zavadenko NN, Alikhanov AA. Role of contrast-free MR-perfusion in the diagnosis of potential epileptogenic foci in children with focal epilepsia. ACTA ACUST UNITED AC 2018. [DOI: 10.17749/2077-8333.2018.10.2.006-018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
ASL (Arterial Spin Labeling) – a novel modality of MR angiography – is based on radio-frequency labeling of aqueous protons in the arterial blood; the method is used to monitor blood supply to organs, including the brain. So far there has been little information on the use of ASL in children with focal epilepsy, especially in the pre-surgery period.Aim:to evaluate the perfusion patterns in seizure-free children with drug resistant focal epilepsy (FE) using the ASL mode of MRI.Materials and methods.We studied the ASL data of 54 (23-boys/31 girls) patients with FE treated in the Dpt. of Neurology at the Russian State Children Hospital from 2015 to 2018. The patients’ age varied from 4 months to 17 years. All images were produced with a 3T GE Discovery 750W system.Results. We found several brain perfusion patterns in children with FE; among other factors, those patterns depended on the clinical status of the patient, i. e. the interictal period or the early post- seizure period. The main pattern of the interictal period was characterized by a focal decrease in perfusion located around a structural focus identified on MRI scans. In the early post-seizure period, there was an increase in the arterial perfusion in the area of a structural epileptogenic lesion.Conclusion.ASL-MRI is an effective diagnostic method providing more information on children with FE during their pre-surgery phase. The ASL modality needs further research to rationalize its wider use as a preferred diagnostic tool or as a combination with the more complex PET and SPECT.
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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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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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Bansal V, Kumar S, Sharma S, Sharma S, Sood RG. Usefulness of Pulsed Arterial Spin Labeling Magnetic Resonance Imaging in New-onset Seizure Patients and Its Comparison with Dynamic Susceptibility Contrast Magnetic Resonance Imaging. J Neurosci Rural Pract 2017; 8:569-574. [PMID: 29204016 PMCID: PMC5709879 DOI: 10.4103/jnrp.jnrp_141_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Introduction Dynamic susceptibility contrast (DSC) perfusion and pulsed arterial spin labeling (PASL) imaging are newer advanced magnetic resonance sequences which are capable of detecting vascular changes in patients with new-onset seizure disorder even when no significant abnormalities are visualized on conventional sequences. The purpose of our study is to establish utility of arterial spin labeling (ASL) in new-onset seizure patients and compare ASL with DSC perfusion sequence. Materials and Methods Twenty-six patients coming to emergency department with new-onset seizure disorder were evaluated using DSC and ASL sequence. Perfusion asymmetry was assessed using region of interests taken at places where signal asymmetry was maximal. Results PASL sequence showed focal vascular changes in form of hyperperfusion in four patients, hypoperfusion in nine patients, and normal perfusion in 13 patients. Altered perfusion whether hypo/hyperperfusion was detected in five out of 16 patients even when conventional sequences were normal. There was strong positive linear correlation between ASL and DSC with P = 0.001. Conclusion Noninvasive PASL is capable of detecting vascular changes induced by seizure and is comparable to DSC sequence. Thus, it is recommended when there is a need for repeated evaluations; in follow-up/therapy response assessment and when contrast administration is contraindicated.
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Affiliation(s)
- Varun Bansal
- Department of Radio-Diagnosis, IGMC, Shimla, Himachal Pradesh, India
| | - Suresh Kumar
- Department of Radio-Diagnosis, IGMC, Shimla, Himachal Pradesh, India
| | - Sudhir Sharma
- Department of Neurology, IGMC, Shimla, Himachal Pradesh, India
| | - Sanjiv Sharma
- Department of Radio-Diagnosis, IGMC, Shimla, Himachal Pradesh, India
| | - R G Sood
- Department of Radio-Diagnosis, IGMC, Shimla, Himachal Pradesh, India
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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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29
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Exploring the Epileptic Brain Network Using Time-Variant Effective Connectivity and Graph Theory. IEEE J Biomed Health Inform 2017; 21:1411-1421. [DOI: 10.1109/jbhi.2016.2607802] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Haller S, Zaharchuk G, Thomas DL, Lovblad KO, Barkhof F, Golay X. Arterial Spin Labeling Perfusion of the Brain: Emerging Clinical Applications. Radiology 2017; 281:337-356. [PMID: 27755938 DOI: 10.1148/radiol.2016150789] [Citation(s) in RCA: 323] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Arterial spin labeling (ASL) is a magnetic resonance (MR) imaging technique used to assess cerebral blood flow noninvasively by magnetically labeling inflowing blood. In this article, the main labeling techniques, notably pulsed and pseudocontinuous ASL, as well as emerging clinical applications will be reviewed. In dementia, the pattern of hypoperfusion on ASL images closely matches the established patterns of hypometabolism on fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) images due to the close coupling of perfusion and metabolism in the brain. This suggests that ASL might be considered as an alternative for FDG, reserving PET to be used for the molecular disease-specific amyloid and tau tracers. In stroke, ASL can be used to assess perfusion alterations both in the acute and the chronic phase. In arteriovenous malformations and dural arteriovenous fistulas, ASL is very sensitive to detect even small degrees of shunting. In epilepsy, ASL can be used to assess the epileptogenic focus, both in peri- and interictal period. In neoplasms, ASL is of particular interest in cases in which gadolinium-based perfusion is contraindicated (eg, allergy, renal impairment) and holds promise in differentiating tumor progression from benign causes of enhancement. Finally, various neurologic and psychiatric diseases including mild traumatic brain injury or posttraumatic stress disorder display alterations on ASL images in the absence of visualized structural changes. In the final part, current limitations and future developments of ASL techniques to improve clinical applicability, such as multiple inversion time ASL sequences to assess alterations of transit time, reproducibility and quantification of cerebral blood flow, and to measure cerebrovascular reserve, will be reviewed. © RSNA, 2016 Online supplemental material is available for this article.
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Affiliation(s)
- Sven Haller
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
| | - Greg Zaharchuk
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
| | - David L Thomas
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
| | - Karl-Olof Lovblad
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
| | - Frederik Barkhof
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
| | - Xavier Golay
- From Affidea Centre Diagnostique Radiologique de Carouge, Clos de la Fonderie 1, 1227 Carouge, Switzerland (S.H.); Dept of Surgical Sciences, Div of Radiology, Uppsala Univ, Sweden (S.H.); Dept of Neuroradiology, Univ Hosp Freiburg, Germany (S.H.); Faculty of Medicine Univ of Geneva, Switzerland (S.H.); Dept of Radiology, Stanford Univ, Stanford, Calif (G.Z.); Univ College London, Inst of Neurology, London, England (D.L.T., X.G.); Dept of Diagnostic and Interventional Neuroradiology, Geneva Univ Hosps,Switzerland (K.O.L.); Dept of Radiology & Nuclear Medicine and PET Research, VU Univ Medical Ctr, Amsterdam, the Netherlands (F.B.); and Insts of Neurology and Healthcare Engineering, Univ College London, England (F.B.)
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Verma RK, Abela E, Schindler K, Krestel H, Springer E, Huber A, Weisstanner C, Hauf M, Gralla J, Wiest R. Focal and Generalized Patterns of Cerebral Cortical Veins Due to Non-Convulsive Status Epilepticus or Prolonged Seizure Episode after Convulsive Status Epilepticus - A MRI Study Using Susceptibility Weighted Imaging. PLoS One 2016; 11:e0160495. [PMID: 27486662 PMCID: PMC4972361 DOI: 10.1371/journal.pone.0160495] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 07/20/2016] [Indexed: 11/25/2022] Open
Abstract
Objective The aim of this study was to investigate variant patterns of cortical venous oxygenation during status epilepticus (SE) using susceptibility-weighted imaging (SWI). Methods We analyzed magnetic resonance imaging (MRI) scans of 26 patients with clinically witnessed prolonged seizures and/or EEG-confirmed SE. All MRI exams encompassed SWI, dynamic susceptibility contrast perfusion MRI (MRI-DSC) and diffusion-weighted imaging (DWI). We aimed to identify distinct patterns of SWI signal alterations that revealed regional or global increases of cerebral blood flow (CBF) and DWI restrictions. We hypothesized that SWI-related oxygenation patterns reflect ictal or postictal patterns that resemble SE or sequelae of seizures. Results Sixteen patients were examined during nonconvulsive status epilepticus (NCSE) as confirmed by EEG, a further ten patients suffered from witnessed and prolonged seizure episode ahead of imaging without initial EEG. MRI patterns of 15 of the 26 patients revealed generalized hyperoxygenation by SWI in keeping with either global or multifocal cortical hyperperfusion. Eight patients revealed a focal hyperoxygenation pattern related to focal CBF increase and three patients showed a focal deoxygenation pattern related to focal CBF decrease. Conclusions SWI-related hyper- and deoxygenation patterns resemble ictal and postictal CBF changes within a range from globally increased to focally decreased perfusion. In all 26 patients the SWI patterns were in keeping with ictal hyperperfusion (hyperoxygenation patterns) or postictal hypoperfusion (deoxygenation patterns) respectively. A new finding of this study is that cortical venous patterns in SWI can be not only focally, but globally attenuated. SWI may thus be considered as an alternative contrast-free MR sequence to identify perfusion changes related to ictal or postictal conditions.
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Affiliation(s)
- Rajeev Kumar Verma
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
- Institute of Radiology and Neuroradiology, Tiefenau Hospital, Bern, Switzerland
- * E-mail:
| | - Eugenio Abela
- Department of Neurology, Inselspital, University of Bern, Bern, Switzerland
| | - Kaspar Schindler
- Department of Neurology, Inselspital, University of Bern, Bern, Switzerland
| | - Heinz Krestel
- Department of Neurology, Inselspital, University of Bern, Bern, Switzerland
| | - Elisabeth Springer
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Adrian Huber
- University Institute for Diagnostic and Interventional Radiology, Inselspital, University of Bern, Bern, Switzerland
| | - Christian Weisstanner
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Martinus Hauf
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Jan Gralla
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Roland Wiest
- University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
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Chen G, Lei D, Ren J, Zuo P, Suo X, Wang DJJ, Wang M, Zhou D, Gong Q. Patterns of postictal cerebral perfusion in idiopathic generalized epilepsy: a multi-delay multi-parametric arterial spin labelling perfusion MRI study. Sci Rep 2016; 6:28867. [PMID: 27374369 PMCID: PMC4931466 DOI: 10.1038/srep28867] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/06/2016] [Indexed: 02/05/2023] Open
Abstract
The cerebral haemodynamic status of idiopathic generalized epilepsy (IGE) is a very complicated process. Little attention has been paid to cerebral blood flow (CBF) alterations in IGE detected by arterial spin labelling (ASL) perfusion magnetic resonance imaging (MRI). However, the selection of an optimal delay time is difficult for single-delay ASL. Multi-delay multi-parametric ASL perfusion MRI overcomes the limitations of single-delay ASL. We applied multi-delay multi-parametric ASL perfusion MRI to investigate the patterns of postictal cerebral perfusion in IGE patients with absence seizures. A total of 21 IGE patients with absence seizures and 24 healthy control subjects were enrolled. IGE patients exhibited prolonged arterial transit time (ATT) in the left superior temporal gyrus. The mean CBF of IGE patients was significantly increased in the left middle temporal gyrus, left parahippocampal gyrus and left fusiform gyrus. Prolonged ATT in the left superior temporal gyrus was negatively correlated with the age at onset in IGE patients. This study demonstrated that cortical dysfunction in the temporal lobe and fusiform gyrus may be related to epileptic activity in IGE patients with absence seizures. This information can play an important role in elucidating the pathophysiological mechanism of IGE from a cerebral haemodynamic perspective.
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Affiliation(s)
- Guangxiang Chen
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China.,Department of Radiology, Affiliated Hospital of Luzhou Medical College, Luzhou, Sichuan Province, China
| | - Du Lei
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | - Jiechuan Ren
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | - Panli Zuo
- Siemens Healthcare, MR Collaborations NE Asia, Beijing, China
| | - Xueling Suo
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | | | - Meiyun Wang
- Department of Radiology, Henan Provincial People's Hospital &the People's Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Dong Zhou
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
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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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Arterial Spin Labeling Techniques 2009-2014. J Med Imaging Radiat Sci 2016; 47:98-107. [PMID: 31047171 DOI: 10.1016/j.jmir.2015.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 07/03/2015] [Accepted: 08/18/2015] [Indexed: 12/23/2022]
Abstract
PURPOSE Arterial spin labeling (ASL) techniques have been implemented across a diverse range of clinical and experimental applications. This review aims to evaluate the current feasibility of ASL in clinical neuroradiology based on recent improvements to ASL sequences and highlight areas for potential clinical applications. METHODS AND MATERIALS In December 2014, a literature search was conducted on PubMed Central, EMBASE, and Scopus using the search terms: "arterial spin labeling, neuroradiology," for studies published between 2009 and 2014 (inclusive). Of 483 studies matching the inclusion criteria, the number of studies using continuous, pseudocontinuous, pulsed, and velocity-selective ASL sequences was 42, 209, 226, and 3, respectively. Studies were classified based on several common clinical applications according to the type of ASL sequence used. Studies using pulsed ASL and pseudo-continuous ASL were grouped based on common sequences. RESULTS The number of clinical studies was 264. Numerous studies applied ASL to stroke management (43 studies), drug testing (21 studies), neurodegenerative diseases (40 studies), and psychiatric disorders (26 studies). CONCLUSIONS This review discusses several factors hindering the implementation of clinical ASL and ASL-related radiofrequency safety issues encountered in clinical practice. However, a limited number of search terms were used. Further development of robust sequences with multislice imaging capabilities and reduced radiofrequency energy deposition will hopefully improve the clinical acceptance of ASL.
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A neuroradiologist's guide to arterial spin labeling MRI in clinical practice. Neuroradiology 2015; 57:1181-202. [PMID: 26351201 PMCID: PMC4648972 DOI: 10.1007/s00234-015-1571-z] [Citation(s) in RCA: 173] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/05/2015] [Indexed: 01/01/2023]
Abstract
Arterial spin labeling (ASL) is a non-invasive MRI technique to measure cerebral blood flow (CBF). This review provides a practical guide and overview of the clinical applications of ASL of the brain, as well its potential pitfalls. The technical and physiological background is also addressed. At present, main areas of interest are cerebrovascular disease, dementia and neuro-oncology. In cerebrovascular disease, ASL is of particular interest owing to its quantitative nature and its capability to determine cerebral arterial territories. In acute stroke, the source of the collateral blood supply in the penumbra may be visualised. In chronic cerebrovascular disease, the extent and severity of compromised cerebral perfusion can be visualised, which may be used to guide therapeutic or preventative intervention. ASL has potential for the detection and follow-up of arteriovenous malformations. In the workup of dementia patients, ASL is proposed as a diagnostic alternative to PET. It can easily be added to the routinely performed structural MRI examination. In patients with established Alzheimer’s disease and frontotemporal dementia, hypoperfusion patterns are seen that are similar to hypometabolism patterns seen with PET. Studies on ASL in brain tumour imaging indicate a high correlation between areas of increased CBF as measured with ASL and increased cerebral blood volume as measured with dynamic susceptibility contrast-enhanced perfusion imaging. Major advantages of ASL for brain tumour imaging are the fact that CBF measurements are not influenced by breakdown of the blood–brain barrier, as well as its quantitative nature, facilitating multicentre and longitudinal studies.
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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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Zhang J. How far is arterial spin labeling MRI from a clinical reality? Insights from arterial spin labeling comparative studies in Alzheimer's disease and other neurological disorders. J Magn Reson Imaging 2015; 43:1020-45. [PMID: 26250802 DOI: 10.1002/jmri.25022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/16/2015] [Accepted: 07/19/2015] [Indexed: 12/26/2022] Open
Affiliation(s)
- Jing Zhang
- Department of Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada
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Bisdas S, lá Fougere C, Ernemann U. Hybrid MR-PET in Neuroimaging. Clin Neuroradiol 2015; 25 Suppl 2:275-81. [DOI: 10.1007/s00062-015-0427-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/25/2015] [Indexed: 12/27/2022]
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Patient-specific detection of cerebral blood flow alterations as assessed by arterial spin labeling in drug-resistant epileptic patients. PLoS One 2015; 10:e0123975. [PMID: 25946055 PMCID: PMC4422723 DOI: 10.1371/journal.pone.0123975] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 02/24/2015] [Indexed: 11/19/2022] Open
Abstract
Electrophysiological and hemodynamic data can be integrated to accurately and precisely identify the generators of abnormal electrical activity in drug-resistant focal epilepsy. Arterial Spin Labeling (ASL), a magnetic resonance imaging (MRI) technique for quantitative noninvasive measurement of cerebral blood flow (CBF), can provide a direct measure of variations in cerebral perfusion associated with the epileptic focus. In this study, we aimed to confirm the ASL diagnostic value in the identification of the epileptogenic zone, as compared to electrical source imaging (ESI) results, and to apply a template-based approach to depict statistically significant CBF alterations. Standard video-electroencephalography (EEG), high-density EEG, and ASL were performed to identify clinical seizure semiology and noninvasively localize the epileptic focus in 12 drug-resistant focal epilepsy patients. The same ASL protocol was applied to a control group of 17 healthy volunteers from which a normal perfusion template was constructed using a mixed-effect approach. CBF maps of each patient were then statistically compared to the reference template to identify perfusion alterations. Significant hypo- and hyperperfused areas were identified in all cases, showing good agreement between ASL and ESI results. Interictal hypoperfusion was observed at the site of the seizure in 10/12 patients and early postictal hyperperfusion in 2/12. The epileptic focus was correctly identified within the surgical resection margins in the 5 patients who underwent lobectomy, all of which had good postsurgical outcomes. The combined use of ESI and ASL can aid in the noninvasive evaluation of drug-resistant epileptic patients.
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Guo X, Xu S, Wang G, Zhang Y, Guo L, Zhao B. Asymmetry of cerebral blood flow measured with three-dimensional pseudocontinuous arterial spin-labeling mr imaging in temporal lobe epilepsy with and without mesial temporal sclerosis. J Magn Reson Imaging 2015; 42:1386-97. [DOI: 10.1002/jmri.24920] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 04/01/2015] [Indexed: 11/09/2022] Open
Affiliation(s)
- Xiaoqin Guo
- Shandong Medical Imaging Research Institute; Shandong University; Jinan People's Republic of China
| | - Shangchen Xu
- Department of Neurosurgery; Shandong Provincial Hospital; Jinan People's Republic of China
| | - Guangbin Wang
- Shandong Medical Imaging Research Institute; Shandong University; Jinan People's Republic of China
| | - Yi Zhang
- Shandong Medical Imaging Research Institute; Shandong University; Jinan People's Republic of China
| | - Lingfei Guo
- Shandong Medical Imaging Research Institute; Shandong University; Jinan People's Republic of China
| | - Bin Zhao
- Shandong Medical Imaging Research Institute; Shandong University; Jinan People's Republic of China
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Recent imaging advances in neurology. J Neurol 2015; 262:2182-94. [PMID: 25808503 DOI: 10.1007/s00415-015-7711-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/13/2015] [Accepted: 03/14/2015] [Indexed: 01/08/2023]
Abstract
Over the recent years, the application of neuroimaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET) has considerably advanced the understanding of complex neurological disorders. PET is a powerful molecular imaging tool, which investigates the distribution and binding of radiochemicals attached to biologically relevant molecules; as such, this technique is able to give information on biochemistry and metabolism of the brain in health and disease. MRI uses high intensity magnetic fields and radiofrequency pulses to provide structural and functional information on tissues and organs in intact or diseased individuals, including the evaluation of white matter integrity, grey matter thickness and brain perfusion. The aim of this article is to review the most recent advances in neuroimaging research in common neurological disorders such as movement disorders, dementia, epilepsy, traumatic brain injury and multiple sclerosis, and to evaluate their contribution in the diagnosis and management of patients.
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High density EEG-what do we have to lose? Clin Neurophysiol 2014; 126:433-4. [PMID: 25113273 DOI: 10.1016/j.clinph.2014.07.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 11/22/2022]
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Boscolo Galazzo I, Storti SF, Formaggio E, Pizzini FB, Fiaschi A, Beltramello A, Bertoldo A, Manganotti P. Investigation of brain hemodynamic changes induced by active and passive movements: A combined arterial spin labeling-BOLD fMRI study. J Magn Reson Imaging 2013; 40:937-48. [DOI: 10.1002/jmri.24432] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 08/30/2013] [Indexed: 12/13/2022] Open
Affiliation(s)
- Ilaria Boscolo Galazzo
- Department of Neurological and Movement Sciences, Section of Neurology; University of Verona; Italy
| | - Silvia F. Storti
- Department of Neurological and Movement Sciences, Section of Neurology; University of Verona; Italy
| | - Emanuela Formaggio
- Department of Neurophysiology Foundation IRCCS; San Camillo Hospital; Venice Italy
| | | | - Antonio Fiaschi
- Department of Neurological and Movement Sciences, Section of Neurology; University of Verona; Italy
- Department of Neurophysiology Foundation IRCCS; San Camillo Hospital; Venice Italy
- Clinical Neurophysiology and Functional Neuroimaging Unit; AOUI of Verona; Italy
| | | | | | - Paolo Manganotti
- Department of Neurological and Movement Sciences, Section of Neurology; University of Verona; Italy
- Department of Neurophysiology Foundation IRCCS; San Camillo Hospital; Venice Italy
- Clinical Neurophysiology and Functional Neuroimaging Unit; AOUI of Verona; Italy
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