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Brain structural changes in preschool children with MRI-negative epilepsy. Neuroradiology 2023; 65:945-959. [PMID: 36869933 DOI: 10.1007/s00234-023-03137-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 02/23/2023] [Indexed: 03/05/2023]
Abstract
PURPOSE To investigate abnormalities in cortical and subcortical structures of the brain in preschool children with MRI-negative epilepsy. METHODS Cortical thickness, cortical mean curvature, cortical surface area, cortical volume, and volumes of subcortical structures were measured using Freesurfer software in preschool children with epilepsy and age-matched controls. RESULTS Findings showed cortical thickening in the left fusiform gyrus, left middle temporal gyrus, right suborbital sulcus, and right gyrus rectus, and cortical thinning mainly in the parietal lobe of preschool children with epilepsy compared to controls. The difference in cortical thickness in the left superior parietal lobule remained after correction for multiple comparisons and was negatively correlated with duration of epilepsy. Cortical mean curvature, surface area, and volume were mainly altered in the frontal and temporal lobes. Changes in mean curvature in the right pericallosal sulcus were positively correlated with age at seizure onset, and changes in mean curvature in the left intraparietal sulcus and transverse parietal sulcus were positively correlated with frequency of seizures. There were no significant differences in the volumes of the subcortical structures. CONCLUSION Changes in preschool children with epilepsy occur in the cortical rather than subcortical structures of the brain. These findings further our understanding of the effects of epilepsy in preschool children and will inform management of epilepsy in this patient population.
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Maher C, D'Souza A, Zeng R, Barnett M, Kavehei O, Nikpour A, Wang C. White matter alterations in focal to bilateral tonic-clonic seizures. Front Neurol 2022; 13:972590. [PMID: 36188403 PMCID: PMC9515421 DOI: 10.3389/fneur.2022.972590] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
We examined the white matter of patients with and without focal to bilateral tonic-clonic seizures (FBTCS), and control participants. A neural network based tract segmentation model (Tractseg) was used to isolate tract-specific, track-weighted tensor-based measurements from the tracts of interest. We compared the group differences in the track-weighted tensor-based measurements derived from whole and hemispheric tracts. We identified several regions that displayed significantly altered white matter in patients with focal epilepsy compared to controls. Furthermore, patients without FBTCS showed significantly increased white matter disruption in the inferior fronto-occipital fascicle and the striato-occipital tract. In contrast, the track-weighted tensor-based measurements from the FBTCS cohort exhibited a stronger resemblance to the healthy controls (compared to the non-FBTCS group). Our findings revealed marked alterations in a range of subcortical tracts considered critical in the genesis of seizures in focal epilepsy. Our novel application of tract-specific, track-weighted tensor-based measurements to a new clinical dataset aided the elucidation of specific tracts that may act as a predictive biomarker to distinguish patients likely to develop FBTCS.
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Affiliation(s)
- Christina Maher
- School of Biomedical Engineering, Faculty of Engineering, The University of Sydney, Sydney, NSW, Australia
- Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
- Australian Research Council Training Centre for Innovative BioEngineering, The University of Sydney, Sydney, NSW, Australia
- *Correspondence: Christina Maher
| | - Arkiev D'Souza
- Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
- Translational Research Collective, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Rui Zeng
- Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
- Translational Research Collective, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Michael Barnett
- Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
- Department of Neurology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
- Sydney Neuroimaging Analysis Centre, Camperdown, NSW, Australia
| | - Omid Kavehei
- School of Biomedical Engineering, Faculty of Engineering, The University of Sydney, Sydney, NSW, Australia
- Australian Research Council Training Centre for Innovative BioEngineering, The University of Sydney, Sydney, NSW, Australia
| | - Armin Nikpour
- Department of Neurology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
- Central Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Chenyu Wang
- Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
- Translational Research Collective, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
- Sydney Neuroimaging Analysis Centre, Camperdown, NSW, Australia
- Chenyu Wang
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Lim SC, Oh J, Hong BY, Lim SH. Changes in the Brain in Temporal Lobe Epilepsy with Unilateral Hippocampal Sclerosis: An Initial Case Series. Healthcare (Basel) 2022; 10:healthcare10091648. [PMID: 36141260 PMCID: PMC9498839 DOI: 10.3390/healthcare10091648] [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: 07/29/2022] [Accepted: 08/27/2022] [Indexed: 11/29/2022] Open
Abstract
Temporal lobe epilepsy (TLE) is a network disorder of the brain. Network disorders predominately involve dysregulation of hippocampal function caused by neuronal hyperexcitability. However, the relationship between the macro- and microscopic changes in specific brain regions is uncertain. In this study, the pattern of brain atrophy in patients with TLE and hippocampal sclerosis (HS) was investigated using volumetry, and microscopic changes in specific lesions were observed to examine the anatomical correspondence with specific target lesions using diffusion tensor imaging (DTI) with statistical parametric mapping (SPM). This retrospective cross-sectional study enrolled 17 patients with TLE and HS. We manually measured the volumes of the hippocampus (HC), amygdala (AMG), entorhinal cortex, fornix, and thalamus (TH) bilaterally. The mean diffusivity and fractional anisotropy of each patient were then quantified and analyzed by a voxel-based statistical correlation method using SPM8. In right TLE with HS, there was no evidence of any abnormal diffusion properties associated with the volume reduction in specific brain regions. In left TLE with HS, there were significant changes in the volumes of the AMG, HC, and TH. Despite the small sample size, these differences in conditions were considered meaningful. Chronic left TLE with HS might cause structural changes in the AMG, HC, and TH, unlike right TLE with HS.
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Affiliation(s)
- Sung Chul Lim
- Department of Neurology, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Juhee Oh
- Department of Neurology, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Bo Young Hong
- Department of Rehabilitation Medicine, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Seong Hoon Lim
- Department of Rehabilitation Medicine, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
- Correspondence: ; Tel.: +82-31-249-8952; Fax: +82-31-251-4481
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Izadi A, Schedlbauer A, Ondek K, Disse G, Ekstrom AD, Cowen SL, Shahlaie K, Gurkoff GG. Early Intervention via Stimulation of the Medial Septal Nucleus Improves Cognition and Alters Markers of Epileptogenesis in Pilocarpine-Induced Epilepsy. Front Neurol 2021; 12:708957. [PMID: 34557145 PMCID: PMC8452867 DOI: 10.3389/fneur.2021.708957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 06/28/2021] [Indexed: 11/13/2022] Open
Abstract
Over one-third of patients with temporal lobe epilepsy are refractory to medication. In addition, anti-epileptic drugs often exacerbate cognitive comorbidities. Neuromodulation is an FDA treatment for refractory epilepsy, but patients often wait >20 years for a surgical referral for resection or neuromodulation. Using a rodent model, we test the hypothesis that 2 weeks of theta stimulation of the medial septum acutely following exposure to pilocarpine will alter the course of epileptogenesis resulting in persistent behavioral improvements. Electrodes were implanted in the medial septum, dorsal and ventral hippocampus, and the pre-frontal cortex of pilocarpine-treated rats. Rats received 30 min/day of 7.7 Hz or theta burst frequency on days 4-16 post-pilocarpine, prior to the development of spontaneous seizures. Seizure threshold, spikes, and oscillatory activity, as well as spatial and object-based learning, were assessed in the weeks following stimulation. Non-stimulated pilocarpine animals exhibited significantly decreased seizure threshold, increased spikes, and cognitive impairments as compared to vehicle controls. Furthermore, decreased ventral hippocampal power (6-10 Hz) correlated with both the development of spikes and impaired cognition. Measures of spikes, seizure threshold, and cognitive performance in both acute 7.7 Hz and theta burst stimulated animals were statistically similar to vehicle controls when tested during the chronic phase of epilepsy, weeks after stimulation was terminated. These data indicate that modulation of the septohippocampal circuit early after pilocarpine treatment alters the progression of epileptic activity, resulting in elevated seizure thresholds, fewer spikes, and improved cognitive outcome. Results from this study support that septal theta stimulation has the potential to serve in combination or as an alternative to high frequency thalamic stimulation in refractory cases and that further research into early intervention is critical.
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Affiliation(s)
- Ali Izadi
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Amber Schedlbauer
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, United States
| | - Katelynn Ondek
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Gregory Disse
- Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Arne D Ekstrom
- Department of Psychology, University of Arizona, Tucson, AZ, United States.,McKnight Brain Institute, University of Arizona, Tucson, AZ, United States
| | - Stephen L Cowen
- Department of Psychology, University of Arizona, Tucson, AZ, United States.,McKnight Brain Institute, University of Arizona, Tucson, AZ, United States
| | - Kiarash Shahlaie
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Gene G Gurkoff
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States
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Wall J, Knight J, Emsley HCA. Late-onset epilepsy predicts stroke: Systematic review and meta-analysis. Epilepsy Behav 2021; 115:107634. [PMID: 33334717 DOI: 10.1016/j.yebeh.2020.107634] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Late-onset epilepsy (LOE) is closely associated with cerebrovascular disease, acting as both a marker of cerebrovascular disease (CVD) and occurring as a direct consequence. Despite this, our understanding of LOE as a cerebrovascular phenomenon is in its infancy. LOE also appears to be a harbinger of dementia. METHODS A systematic review was performed to identify publications relating to LOE and identified observational studies, clinical studies, and radiological studies. RESULTS A meta-analysis of observational studies demonstrated that patients presenting with LOE experience an increased risk of subsequent stroke (weighted OR 3.88 (95% CI 2.76-5.46)). The additional studies demonstrated clinical and radiological evidence to support the premise that LOE is likely to reflect underlying cerebrovascular disease. SIGNIFICANCE Cerebrovascular disease risk factors convey increased risk of LOE and LOE can precede stroke and dementia, acting as an early marker for cerebrovascular risk. This may represent a potential point for intervention. There are a number of suggested mechanisms relating LOE to stroke; however, there is limited understanding of the natural history of LOE. Current data support the need for prospective research in order to understand the natural history of LOE and modify disease, in order to reduce the apparent sequelae of stroke and dementia.
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Affiliation(s)
- Jasmine Wall
- Lancaster Medical School, Lancaster University, Lancaster, UK; Department of Neurology, Royal Preston Hospital, Preston, UK.
| | - Jo Knight
- Lancaster Medical School, Lancaster University, Lancaster, UK; Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Hedley C A Emsley
- Lancaster Medical School, Lancaster University, Lancaster, UK; Department of Neurology, Royal Preston Hospital, Preston, UK
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Aslan K, Gunbey HP, Cortcu S, Ozyurt O, Avci U, Incesu L. Diffusion tensor imaging in hyperthyroidism: assessment of microstructural white matter abnormality with a tract-based spatial statistical analysis. Acta Radiol 2020; 61:1677-1683. [PMID: 32202136 DOI: 10.1177/0284185120909960] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Metabolic, morphological, and functional brain changes associated with a neurological deficit in hyperthyroidism have been observed. However, changes in microstructural white matter (WM), which can explain the underlying pathophysiology of brain dysfunctions, have not been researched. PURPOSE To assess microstructural WM abnormality in patients with untreated or newly diagnosed hyperthyroidism using tract-based spatial statistics (TBSS). MATERIAL AND METHODS Eighteen patients with hyperthyroidism and 14 age- and sex-matched healthy controls were included in this study. TBSS were used in this diffusion tensor imaging study for a whole-brain voxel-wise analysis of fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD) of WM. RESULTS When compared to the control group, TBSS showed a significant increase in the RD of the corpus callosum, anterior and posterior corona radiata, posterior thalamic radiation, cingulum, superior longitudinal fasciculus, and the retrolenticular region of the internal capsule in patients with hyperthyroidism (P < 0.05), as well as a significant decrease in AD in the anterior corona radiata and the genu of corpus callosum (P < 0.05). CONCLUSION This study showed that more regions are affected by the RD increase than the AD decrease in the WM tracts of patients with hyperthyroidism. These preliminary results suggest that demyelination is the main mechanism of microstructural alterations in the WM of hyperthyroid patients.
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Affiliation(s)
- Kerim Aslan
- Department of Radiology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | - Hediye Pinar Gunbey
- Department of Radiology, Health Sciences University Kartal Lütfi Kırdar Training and Research Hospital, Istanbul, Turkey
| | - Sumeyra Cortcu
- Department of Radiology, Kastamonu State Hospital, Kastamonu, Turkey
| | - Onur Ozyurt
- Telemed Solutions Teknopark, Bogazici University, İstanbul, Turkey
| | - Ugur Avci
- Department of Endocrinology and Metabolism, Recep Tayyip Erdogan University Faculty of Medicine, Rize, Turkey
| | - Lutfi Incesu
- Department of Radiology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
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Sanjari Moghaddam H, Rahmani F, Aarabi MH, Nazem-Zadeh MR, Davoodi-Bojd E, Soltanian-Zadeh H. White matter microstructural differences between right and left mesial temporal lobe epilepsy. Acta Neurol Belg 2020; 120:1323-1331. [PMID: 30635771 DOI: 10.1007/s13760-019-01074-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/05/2019] [Indexed: 01/20/2023]
Abstract
PURPOSE Mesial temporal lobe epilepsy (mTLE) is a chronic focal epileptic disorder characterized by recalcitrant seizures often necessitating surgical intervention. Identifying the laterality of seizure focus is crucial for pre-surgical planning. We implemented diffusion MRI (DMRI) connectometry to identify differences in white matter connectivity in patients with left and right mTLE relative to healthy control subjects. METHOD We enrolled 12 patients with right mTLE, 12 patients with left mTLE, and 12 age/sex matched healthy controls (HCs). We used DMRI connectometry to identify local connectivity patterns of white matter tracts, based on quantitative anisotropy (QA). We compared QA of white matter to reconstruct tracts with significant difference in connectivity between patients and HCs and then between patients with left and right mTLE. RESULTS Right mTLE patients show higher anisotropy in left inferior longitudinal fasciculus (ILF) and forceps minor and lower QA in genu of corpus callosum (CC), bilateral corticospinal tracts (CSTs), and bilateral middle cerebellar peduncles (MCPs) compared to HCs. Left mTLE patients show higher anisotropy in genu of CC, bilateral CSTs, and right MCP and decreased anisotropy in forceps minor compared to HCs. Compared to patients with right mTLE, left mTLE patients showed increased and decreased connectivity in some major tracts. CONCLUSIONS Our study showed the pattern of microstructural disintegrity in mTLE patients relative to HCs. We demonstrated that left and right mTLE patients have discrepant alternations in their white matter microstructure. These results may indicate that left and right mTLE have different underlying pathologic mechanisms.
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Affiliation(s)
| | - Farzaneh Rahmani
- NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- Student's Scientific Research Center (SSRC), Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mohammad-Reza Nazem-Zadeh
- Research Center for Science and Technology in Medicine (RCSTIM), Tehran University of Medical Sciences, Tehran, Iran
| | - Esmaeil Davoodi-Bojd
- Image Analysis Laboratory, Departments of Radiology and Research Administration, Henry Ford Health System, One Ford Place, 2F, Detroit, MI, 48202, USA
| | - Hamid Soltanian-Zadeh
- Control and Intelligent Processing Center of Excellence (CIPCE), School of Electrical and Computer Engineering, College of Engineering, University of Tehran, North Kargar Ave., Tehran, Iran.
- Image Analysis Laboratory, Departments of Radiology and Research Administration, Henry Ford Health System, One Ford Place, 2F, Detroit, MI, 48202, USA.
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8
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Gunbey HP, Has AC, Aslan K, Saglam D, Avcı U, Sayıt AT, Incesu L. Microstructural white matter abnormalities in hypothyroidism evaluation with diffusion tensor imaging tract-based spatial statistical analysis. Radiol Med 2020; 126:283-290. [PMID: 32524282 DOI: 10.1007/s11547-020-01234-7] [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: 10/10/2019] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE Hypothyroidism is presented in a wide range from neuropsychiatric problems including depression, memory and cognitive disorders to poor motor coordination. Against the background of morphologic, functional and molecular changes on the white and grey matter of the brain, we aimed to investigate the effects of hypothyroidism on white matter (WM) integrity using tract-based spatial statistics (TBSS). METHODS Eighteen patients with hyperthyroidism and 14 age-sex-matched healthy control subjects were included in this study. TBSS was used in the diffusion tensor imaging study for whole-brain voxel wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) of WM. RESULTS When compared to the control group, the whole brain TBSS revealed extensive reductions of FA in the supratentorial WM including corticospinal tract, posterior limb of the internal capsule (PLIC), uncinate fasciculus, inferior longitudinal fasciculus (p < 0.005). The ROI analyses showed RD increment of superior longitudinal fasciculus, AD decrement of cingulum (CIN), external capsule, PLIC and corpus callosum (CC) in patients with hypothyroidism (p < 0.005). Autoimmune and non-autoimmune hypothyroidism patient subgroups showed a significant difference in terms of hippocampus FA, CIN MD, CC MD, CC AD, CIN RD, SLF RD, CC RD (p < 0.005). CIN FA values showed a negative correlation with the Beck Depression Inventory (p = 0.007, r = - 852). CONCLUSIONS These preliminary results of TBSS analyses represented FA and AD decrement, and RD increment in several WM tracts and indicates the demyelination process underlying pathophysiology of clinical aspects of hypothyroidism.
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Affiliation(s)
- Hediye Pınar Gunbey
- Department of Radiology, University of Health Sciences Kartal Lutfi Kırdar Training and Research Hospital, 34890, Kartal/Istanbul, Turkey.
| | - Arzu Ceylan Has
- Institute of Neuroimmunology and Multiple Sclerosis, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kerim Aslan
- Department of Radiology, Ondokuz Mayıs University Faculty of Medicine, Samsun, Turkey
| | - Dilek Saglam
- Departmant of Radiology, University of Health Sciences Malatya Training and Research Hospital, Malatya, Turkey
| | - Ugur Avcı
- Department of Endocrinology, Recep Tayyip Erdogan University, Rize, Turkey
| | | | - Lutfi Incesu
- Department of Radiology, Ondokuz Mayıs University Faculty of Medicine, Samsun, Turkey
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Buksakowska I, Szabó N, Martinkovič L, Faragó P, Király A, Vrána J, Kincses ZT, Meluzín J, Šulc V, Kynčl M, Roček M, Tichý M, Charvát F, Hořínek D, Marusič P. Distinctive Patterns of Seizure-Related White Matter Alterations in Right and Left Temporal Lobe Epilepsy. Front Neurol 2019; 10:986. [PMID: 31632330 PMCID: PMC6779711 DOI: 10.3389/fneur.2019.00986] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/29/2019] [Indexed: 12/14/2022] Open
Abstract
Background: We hypothesized that right and left temporal lobe epilepsy (RTLE and LTLE, respectively) have distinctive spatial patterns of white matter (WM) changes that can be differentiated and interpreted with the use of multiple diffusion parameters. We compared the global microstructure of fiber bundles with regard to WM alterations in both RTLE and LTLE, addressing some of the methodological issues of previous studies. Methods: Diffusion tensor imaging data from 17 patients with RTLE (age: 40.7 ± 10.4), 15 patients with LTLE (age: 37.3 ± 10.4), and 15 controls (age: 34.8 ± 11.2) were used in the study. WM integrity was quantified by fractional anisotropy (FA), mean diffusivity (MD), longitudinal diffusivity (LD), and radial diffusivity (RD). The diffusion parameters were compared between the groups in tracts representing the core of the fiber bundles. The volumes of hippocampi and amygdala were subsequently compared across the groups, while the data were adjusted for the effect of hippocampal sclerosis. Results: Significantly reduced FA and increased MD, LD, and RD were found bilaterally over widespread brain regions in RTLE. An increase in MD and RD values was observed in widespread WM fiber bundles ipsilaterally in LTLE, largely overlapping with regions where FA was lower, while no increase in LD was observed. We also found a difference between the LTLE and RTLE groups for the right hippocampal volume (with and without adjustment for HS), whereas no significant volume differences were found between patients and controls. Conclusions: It appears that patients with RTLE exhibit a more widespread pattern of WM alterations that extend far beyond the temporal lobe in both ipsilateral and contralateral hemisphere; furthermore, these changes seem to reflect more severe damage related to chronic degeneration. Conversely, more restrained changes in the LTLE may imply a pattern of less severe axonal damage, more restricted to ipsilateral hemisphere. Comprehensive finding of more prominent hippocampal atrophy in the RTLE raises an interesting issue of seizure-induced implications on gray matter and WM microstructure that may not necessarily mean a straightforward causal relationship. Further correlations of diffusion-derived metrics with neuropsychological and functional imaging measures may provide complementary information on underlying WM abnormalities with regard to functional hemispheric specialization.
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Affiliation(s)
- Irena Buksakowska
- Department of Radiology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Nikoletta Szabó
- Department of Neurology, Faculty of General Medicine, University of Szeged, Szeged, Hungary
| | - Lukáš Martinkovič
- Department of Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Péter Faragó
- Department of Neurology, Faculty of General Medicine, University of Szeged, Szeged, Hungary
| | - András Király
- Department of Neurology, Faculty of General Medicine, University of Szeged, Szeged, Hungary
| | - Jiří Vrána
- Department of Radiodiagnostics, University Central Military Hospital, Prague, Czechia
| | - Zsigmond Tamás Kincses
- Department of Neurology, Faculty of General Medicine, University of Szeged, Szeged, Hungary
| | - Jan Meluzín
- Department of Radiology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Vlastimil Šulc
- Department of Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Martin Kynčl
- Department of Radiology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Miloslav Roček
- Department of Radiology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Michal Tichý
- Department of Neurosurgery, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - František Charvát
- Department of Radiodiagnostics, University Central Military Hospital, Prague, Czechia
| | - Daniel Hořínek
- Department of Neurosurgery, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
| | - Petr Marusič
- Department of Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia
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