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Taherpour J, Jaber M, Voges B, Apostolova I, Sauvigny T, House PM, Lanz M, Lindenau M, Klutmann S, Martens T, Stodieck S, Buchert R. Predicting the outcome of epilepsy surgery by covariance pattern analysis of ictal perfusion SPECT. J Nucl Med 2021; 63:925-930. [PMID: 34593599 DOI: 10.2967/jnumed.121.262702] [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: 06/07/2021] [Revised: 09/09/2021] [Indexed: 11/16/2022] Open
Abstract
Previous studies on the utility of specific perfusion patterns in ictal brain perfusion SPECT for predicting the outcome of temporal lobe epilepsy surgery used qualitative visual pattern classification, semi-quantitative region-of-interest analysis or conventional univariate voxel-based testing, which are limited by intra- and inter-rater variability and/or low sensitivity to capture functional interactions among brain regions. The present study performed covariance pattern analysis of ictal perfusion SPECT using the Scaled Subprofile Model for unbiased identification of predictive covariance patterns. Methods: The study retrospectively included 18 responders to temporal lobe epilepsy surgery (Engel I-A at 12 months follow-up) and 18 non-responders (≥ Engel I-B). Ictal SPECT images were analyzed with the Scaled Subprofile Model blinded to group membership for unbiased identification of the 16 covariance patterns explaining the highest proportion of variance in the whole data set. Individual expression scores of the covariance patterns were evaluated for predicting seizure freedom after temporal lobe surgery by ROC analysis. Kaplan-Meier analysis including all available follow-up data (up to 60 months after surgery) was also performed. Results: Amongst the 16 covariance patterns only one showed a different expression between responders and non-responders (P = 0.03). This 'favorable ictal perfusion pattern' resembled the typical ictal perfusion pattern in temporomesial epilepsy. The expression score of the pattern provided an area of 0.744 (95%-confidence interval 0.577-0.911, P = 0.004) under the ROC curve. Kaplan-Meier analysis revealed a statistical trend towards longer seizure freedom in patients with positive expression score (P = 0.06). The median estimated seizure free time was 48 months in patients with positive expression score versus 6 months in patients with negative expression score. Conclusion: The expression of the 'favorable ictal perfusion pattern' identified by covariance analysis of ictal brain perfusion SPECT provides independent (from demographical and clinical variables) information for the prediction of seizure freedom after temporal lobe epilepsy surgery. The expression of this pattern is easily computed for new ictal SPECT images and, therefore, might be used to support the decision for or against temporal lobe surgery in clinical patient care.
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Affiliation(s)
| | - Marian Jaber
- University Medical Center Hamburg-Eppendorf, Germany
| | | | | | | | | | | | | | | | | | | | - Ralph Buchert
- University Medical Center Hamburg-Eppendorf, Germany
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Morgan VL, Rogers BP, Anderson AW, Landman BA, Englot DJ. Divergent network properties that predict early surgical failure versus late recurrence in temporal lobe epilepsy. J Neurosurg 2020; 132:1324-1333. [PMID: 30952126 PMCID: PMC6778487 DOI: 10.3171/2019.1.jns182875] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 01/14/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The objectives of this study were to identify functional and structural network properties that are associated with early versus long-term seizure outcomes after mesial temporal lobe epilepsy (mTLE) surgery and to determine how these compare to current clinically used methods for seizure outcome prediction. METHODS In this case-control study, 26 presurgical mTLE patients and 44 healthy controls were enrolled to undergo 3-T MRI for functional and structural connectivity mapping across an 8-region network of mTLE seizure propagation, including the hippocampus (left and right), insula (left and right), thalamus (left and right), one midline precuneus, and one midline mid-cingulate. Seizure outcome was assessed annually for up to 3 years. Network properties and current outcome prediction methods related to early and long-term seizure outcome were investigated. RESULTS A network model was previously identified across 8 patients with seizure-free mTLE. Results confirmed that whole-network propagation connectivity patterns inconsistent with the mTLE model predict early surgical failure. In those patients with networks consistent with the mTLE network, specific bilateral within-network hippocampal to precuneus impairment (rather than unilateral impairment ipsilateral to the seizure focus) was associated with mild seizure recurrence. No currently used clinical variables offered the same ability to predict long-term outcome. CONCLUSIONS It is known that there are important clinical differences between early surgical failure that lead to frequent disabling seizures and late recurrence of less frequent mild seizures. This study demonstrated that divergent network connectivity variability, whole-network versus within-network properties, were uniquely associated with these disparate outcomes.
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Affiliation(s)
- Victoria L. Morgan
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Baxter P. Rogers
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Adam W. Anderson
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Bennett A. Landman
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, USA
| | - Dario J. Englot
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
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Chaudhari RM, Dash D, Ramanujam B, Rana MK, Appukuttan R, Sharma A, Kunwar Y, Tejaniya G, Padma V, Chandra SP, Tripathi M. Evaluation of Ictal Consciousness in Temporal and Extra Temporal Epilepsy: Observations from a Tertiary Care Hospital in India. J Epilepsy Res 2017; 6:93-96. [PMID: 28101481 PMCID: PMC5206106 DOI: 10.14581/jer.16017] [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: 04/21/2016] [Accepted: 11/25/2016] [Indexed: 11/09/2022] Open
Abstract
Background and Purpose Differences in consciousness during seizures depend on the location of the seizure onset. Methods The present study evaluates ictal consciousness using the ictal consciousness inventory (ICI) in drug refractory mesial temporal (MTLE), neocortical temporal (NTLE) and extra temporal epilepsy (ETLE). This was a cross sectional cohort study with 45 patients with mesial temporal epilepsy, 47 with extra temporal and 11 patients with neocortical temporal epilepsy. The ICI a 20 item questionnaire was used to calculate the scores for level (L, question 1–10) and content (C, question 11–20) of consciousness. Results The patients in mesial temporal group had higher ICI-L scores, p = 0.0129 as compared to the extra temporal group, but no difference was observed in the content of consciousness. The ICI-L and C scores were not different in the mesial temporal and the neocortical temporal group (p = 0.53 and 0.65) respectively. Conclusions Patients with mesial temporal epilepsy had a higher level of consciousness than the extra temporal group but there was no difference in the content. Also there was no difference in the level and content of consciousness between mesial and the neocortical temporal group.
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Affiliation(s)
- Rima M Chaudhari
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Deepa Dash
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Bhargavi Ramanujam
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Manit K Rana
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Renjith Appukuttan
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Anubha Sharma
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Yuvraj Kunwar
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Gaurav Tejaniya
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Vasantha Padma
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
| | - Sarat P Chandra
- Department of Neurosurgery, All India Institute of Medical sciences, New Delhi, India
| | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical sciences, New Delhi, India
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Morgan VL, Rogers BP, Abou-Khalil B. Segmentation of the thalamus based on BOLD frequencies affected in temporal lobe epilepsy. Epilepsia 2015; 56:1819-27. [PMID: 26360535 DOI: 10.1111/epi.13186] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Temporal lobe epilepsy is associated with functional changes throughout the brain, particularly including a putative seizure propagation network involving the hippocampus, insula, and thalamus. We identified a specified frequency range where functional connectivity in this network was related to duration of disease. Then, to identify specific thalamic nuclei involved in seizure propagation, we determined the subregions of the thalamus that have increased resting functional oscillations in this frequency range. METHODS Resting-state functional magnetic resonance imaging (fMRI) was acquired from 20 patients with unilateral temporal lobe epilepsy (TLE; 14 right and 6 left) and 20 healthy controls who were each age and gender matched to a specific patient. Wavelet-based fMRI connectivity mapping across the network was computed at each frequency to determine those frequencies where connectivity significantly decreases with duration of disease consistent with impairment due to repeated seizures. The voxel-wise power of the spontaneous blood oxygenation fluctuations of this frequency band was computed in the thalamus of each subject. RESULTS Functional connectivity was impaired in the proposed seizure propagation network over a specific range (0.0067-0.013 Hz and 0.024-0.032 Hz) of blood oxygenation oscillations. Increased power in this frequency band (<0.032 Hz) was detected bilaterally in the pulvinar and anterior nucleus of the thalamus of healthy controls, and was increased over the ipsilateral thalamus compared to the contralateral thalamus in TLE. SIGNIFICANCE This study identified frequencies of impaired connectivity in a TLE seizure propagation network and used them to localize the anterior nucleus and pulvinar of the thalamus as subregions most susceptible to TLE seizures. Further examinations of these frequencies in healthy and TLE subjects may provide unique information relating to the mechanism of seizure propagation and potential treatment using electrical stimulation.
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Affiliation(s)
- Victoria L Morgan
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Baxter P Rogers
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Bassel Abou-Khalil
- Department of Neurology, Vanderbilt University, Nashville, Tennessee, U.S.A
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Morgan VL, Conrad BN, Abou-Khalil B, Rogers BP, Kang H. Increasing structural atrophy and functional isolation of the temporal lobe with duration of disease in temporal lobe epilepsy. Epilepsy Res 2014; 110:171-8. [PMID: 25616470 DOI: 10.1016/j.eplepsyres.2014.12.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/21/2014] [Accepted: 12/04/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Due to pharmacoresistant seizures and the underutilization of surgical treatments, a large number of temporal lobe epilepsy (TLE) patients experience seizures for years or decades. The goal of this study was to generate a predictive model of duration of disease with the least number of parameters possible in order to identify and quantify the significant volumetric and functional indicators of TLE progression. METHODS Two cohorts of subjects including 12 left TLE, 21 right TLE and 20 healthy controls (duration = 0) were imaged on a 3T MRI scanner using high resolution T1-weighted structural MRI and 20 min of resting functional MRI scanning. Multivariate linear regression methods were used to compute a predictive model of duration of disease using 49 predictors including functional connectivity and gray matter volumes computed from these images. RESULTS No model developed from the full set of data accurately predicted the duration of disease across the entire range from 3 to 50 years. We then performed the regression on 35 subjects with durations of disease in the range 10 to 35 years. The resulting predictive model showed that longer durations were associated with reductions in functional connectivity from the ipsilateral temporal lobe to the contralateral temporal lobe, precuneus and mid cingulate, and with decreases in volume of the ipsilateral hippocampus and pallidum. CONCLUSIONS Functional and volumetric parameters accurately predicted duration of disease in TLE. The findings suggest that TLE is associated with a gradual functional isolation and significant progressive structural atrophy of the ipsilateral temporal lobe over years of duration in the range of 10-35 years. Furthermore, these changes can also be detected in the contralateral hemisphere in these patients, but to a lesser degree.
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Affiliation(s)
- Victoria L Morgan
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA.
| | - Benjamin N Conrad
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
| | | | - Baxter P Rogers
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University, Nashville, TN, USA
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Tepmongkol S, Tangtrairattanakul K, Lerdlum S, Desudchit T. Comparison of brain perfusion SPECT parameters accuracy for seizure localization in extratemporal lobe epilepsy with discordant pre-surgical data. Ann Nucl Med 2014; 29:21-8. [PMID: 25212388 DOI: 10.1007/s12149-014-0905-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 09/04/2014] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Extratemporal lobe epilepsy is difficult to localize. We aimed to define the best parameter(s) of SPECT for confirmation of seizure origin among the region of maximum cerebral perfusion in ictal phase (MP), maximum change of cerebral perfusion from interictal to ictal phase (MC), and maximum extent of hyperperfusion in ictal phase (ME) of (99m)Tc ECD brain perfusion SPECT as well as combined SPECT parameters, and combined SPECT and MRI for seizure localization in extratemporal lobe epilepsy. MATERIALS AND METHODS Twenty intractable extratemporal lobe epilepsy patients who had (99m)Tc-ECD brain SPECT were reviewed. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of single SPECT parameter, combined SPECT parameters, and combined SPECT and MRI parameters for localization of seizure origin were calculated using pathology and surgical outcomes (Engel class I and II) as gold standards. RESULTS Combined SPECT parameters provided more specificity, PPV and accuracy than single SPECT parameters. The best combined SPECT parameters was MP+MC with 80.6 % accuracy, 92.4 % specificity and 43.8 % PPV. Combination of SPECT parameter with MRI (ME+MRI) was the most sensitive (41.7 %), specific (97.5 %), accurate (88.2 %) parameter and had highest PPV (76.9 %) and NPV (89.3 %) for seizure localization. It improved specificity and PPV when compared to MRI alone. CONCLUSION Combined SPECT parameters improved the specificity and accuracy in seizure localization. The most specific and accurate SPECT combination is MP+MC. The combined SPECT parameter with MRI further improved sensitivity, specificity, accuracy, PPV and NPV. The authors recommend using SPECT combination, MP+MC, when MRI is negative and ME+MRI when there is MRI lesion.
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Affiliation(s)
- Supatporn Tepmongkol
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Rama 4 Road, Pathumwan, Bangkok, 10330, Thailand,
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Xu Q, Zhang Z, Liao W, Xiang L, Yang F, Wang Z, Chen G, Tan Q, Jiao Q, Lu G. Time-shift homotopic connectivity in mesial temporal lobe epilepsy. AJNR Am J Neuroradiol 2014; 35:1746-52. [PMID: 24742802 DOI: 10.3174/ajnr.a3934] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND AND PURPOSE Voxel-mirrored intrinsic functional connectivity allows the depiction of interhemispheric homotopic connections in the human brain, whereas time-shift intrinsic functional connectivity allows the detection of the extent of brain injury by measuring hemodynamic properties. We combined time-shift voxel-mirrored homotopic connectivity analyses to investigate the alterations in homotopic connectivity in mesial temporal lobe epilepsy and assessed the value of applying this approach to epilepsy lateralization and the prediction of surgical outcomes in mesial temporal lobe epilepsy. MATERIALS AND METHODS Resting-state functional MR imaging data were acquired from patients with unilateral mesial temporal lobe epilepsy (n=62) (31 left- and 31 right-side) and healthy controls (n=33). Dynamic interhemispheric homotopic architecture seeding from each hemisphere was individually calculated by 0, 1, 2, and 3 repetition time time-shift voxel-mirrored homotopic connectivity. Voxel-mirrored homotopic connectivity maps were compared between the patient and control groups by using 1-way ANOVA for each time-shift condition, separately. Group comparisons were further performed on the laterality of voxel-mirrored homotopic connectivity in each time-shift condition. Finally, we correlated the interhemispheric homotopic connection to the surgical outcomes in a portion of the patients (n=20). RESULTS The patients with mesial temporal lobe epilepsy showed decreased homotopic connectivity in the mesial temporal structures, temporal pole, and striatum. Alterations of the bihemispheric homotopic connectivity were lateralized along with delays in the time-shift in mesial temporal lobe epilepsy. The patients with unsuccessful surgical outcomes presented larger interhemispheric voxel-mirrored homotopic connectivity differences. CONCLUSIONS This study showed whole patterns of dynamic alterations of interhemispheric homotopic connectivity in mesial temporal lobe epilepsy, extending the knowledge of abnormalities in interhemispheric connectivity in this condition. Time-shift voxel-mirrored homotopic connectivity has the potential for lateralization of unilateral mesial temporal lobe epilepsy and may have the capability of predicting surgical outcomes in this condition.
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Affiliation(s)
- Q Xu
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.)
| | - Z Zhang
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.)
| | - W Liao
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.) Center for Cognition and Brain Disorders and the Affiliated Hospital (W.L.), Hangzhou Normal University, Hangzhou, China Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments (W.L.), Hangzhou, China
| | - L Xiang
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.)
| | | | - Z Wang
- Department of Medical Imaging (Z.W.), Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | | | - Q Tan
- Neurosurgery (Q.T.), Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Q Jiao
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.) Department of Medical Imaging (Q.J.), Taishan Medical College, TaiAn, China
| | - G Lu
- From the Departments of Medical Imaging (Q.X., Z.Z., W.L., L.X., Q.J., G.L.)
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Morgan VL, Abou-Khalil B, Rogers BP. Evolution of functional connectivity of brain networks and their dynamic interaction in temporal lobe epilepsy. Brain Connect 2014; 5:35-44. [PMID: 24901036 DOI: 10.1089/brain.2014.0251] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study presents a cross-sectional investigation of functional networks in temporal lobe epilepsy (TLE) as they evolve over years of disease. Networks of interest were identified based on a priori hypotheses: the network of seizure propagation ipsilateral to the seizure focus, the same regions contralateral to seizure focus, the cross hemisphere network of the same regions, and a cingulate midline network. Resting functional magnetic resonance imaging data were acquired for 20 min in 12 unilateral TLE patients, and 12 age- and gender-matched healthy controls. Functional changes within and between the four networks as they evolve over years of disease were quantified by standard measures of static functional connectivity and novel measures of dynamic functional connectivity. The results suggest an initial disruption of cross-hemispheric networks and an increase in static functional connectivity in the ipsilateral temporal network accompanying the onset of TLE seizures. As seizures progress over years, the static functional connectivity across the ipsilateral network diminishes, while dynamic functional connectivity measures show the functional independence of this ipsilateral network from the network of midline regions of the cingulate declines. This implies a gradual breakdown of the seizure onset and early propagation network involving the ipsilateral hippocampus and temporal lobe as it becomes more synchronous with the network of regions responsible for secondary generalization of the seizures, a process that may facilitate the spread of seizures across the brain. Ultimately, the significance of this evolution may be realized in relating it to symptoms and treatment outcomes of TLE.
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Affiliation(s)
- Victoria L Morgan
- 1 Department of Radiology, Vanderbilt University , Nashville, Tennessee
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Morgan VL, Gore JC, Abou-Khalil B. Functional epileptic network in left mesial temporal lobe epilepsy detected using resting fMRI. Epilepsy Res 2009; 88:168-78. [PMID: 19945255 DOI: 10.1016/j.eplepsyres.2009.10.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 10/26/2009] [Accepted: 10/29/2009] [Indexed: 10/20/2022]
Abstract
The purpose of this study was to determine transient functional signal activity in a small, homogeneous group of left temporal lobe epilepsy (TLE) patients, without the use of EEG; and to use one of these activated regions to identify a possible epileptogenic network across the whole brain in this group. Resting functional MRI scanning was performed on five left TLE patients who underwent selective amygdalohippocampectomy resulting in seizure control and 10 healthy control subjects. Activation maps of functional signal peaks were calculated using a data-driven analysis, 2dTCA, across the group of patients. In addition to the expected region of activation in the left anterior hippocampus, the results of the 2dTCA analysis revealed activity in the bilateral insular cortex and default-mode network which are not commonly reported using fMRI, but are supported by other electrical and functional changes. The region of activation corresponding to the anterior hippocampal region of resection (presumably the epileptogenic region) was used as a seed region for fMRI functional connectivity analysis. This revealed increased negative connectivity in the patients as compared to controls across a network including thalamic, brainstem, frontal and parietal regions consistent with theories of inhibited function in subcortical and cortical structures during ictal propagation.
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Affiliation(s)
- Victoria L Morgan
- AA 1105 MCN, Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232-2310, USA.
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Dynamic perfusion patterns in temporal lobe epilepsy. Eur J Nucl Med Mol Imaging 2009; 36:823-30. [DOI: 10.1007/s00259-008-1040-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 11/28/2008] [Indexed: 11/26/2022]
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