R Edward Hogan

Washington University in St. Louis, San Luis, Missouri, United States

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Publications (44)169.3 Total impact

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    ABSTRACT: Preclinical and clinical studies have demonstrated the significance of inflammation and autoantibodies in epilepsy, and the use of immunotherapies in certain situations has become an established practice. Temporal lobe epilepsy can follow paraneoplastic or nonparaneoplastic limbic encephalitis associated with antibodies directed against brain antigens. Here, we focus on a patient with worsening confusion and temporal lobe seizures despite treatment with antiepileptic medications. Serial brain MRIs did not conclusively reveal structural abnormalities, so the patient underwent brain PET/MRI to simultaneously evaluate brain structure and function, revealing bitemporal abnormalities. The patient was diagnosed with voltage-gated potassium channel antibody-related limbic encephalitis based on clinical presentation, imaging findings, and antibody testing. Treatment included the addition of a second antiepileptic agent and oral steroids. His seizures and cognitive deficits improved and stabilized.
    12/2015; 4. DOI:10.1016/j.ebcr.2015.02.002
  • Epilepsy & Behavior 05/2015; 46. DOI:10.1016/j.yebeh.2015.02.046 · 2.06 Impact Factor
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    ABSTRACT: Hippocampal atrophy in temporal lobe epilepsy (TLE) can indicate mesial temporal sclerosis and predict surgical success. Yet many patients with TLE do not have significant atrophy (magnetic resonance imaging (MRI) negative), which presents a diagnostic challenge. We used a new variant of high-dimensional large-deformation mapping to assess whether patients with apparently normal hippocampi have local shape changes that mirror those of patients with significant hippocampal atrophy. Forty-seven patients with unilateral TLE and 32 controls underwent structural brain MRI. High-dimensional large-deformation mapping provided hippocampal surface and volume estimates for each participant, dividing patients into low versus high hippocampal atrophy groups. A vertex-level generalized linear model compared local shape changes between groups. Patients with low-atrophy TLE (MRI negative) had significant local hippocampal shape changes compared to controls, similar to those in the contralateral hippocampus of high-atrophy patients. These changes primarily involved the subicular and hilar/dentate regions, instead of the classically affected CA1 region. Disease duration instead co-varied with lateral hippocampal atrophy, co-localizing with the CA1 subfield. These findings show that patients with "MRI-negative" TLE have regions of hippocampal atrophy that cluster medially, sparing the lateral regions (CA1) involved in high-atrophy patients. This suggests an overall effect of temporal lobe seizures manifesting as bilateral medial hippocampal atrophy, and a more selective effect of hippocampal seizures leading to disease-proportional CA1 atrophy, potentially reflecting epileptogenesis. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.
    Epilepsia 03/2015; 56(5). DOI:10.1111/epi.12955 · 4.58 Impact Factor
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    ABSTRACT: Since its introduction to neurosurgery in 2008, laser ablative techniques have been largely confined to the management of unresectable tumors. Application of this technology for the management of focal epilepsy in the adult population has not been fully explored. Given that nearly 1,000,000 Americans live with medically refractory epilepsy and current surgical techniques only address a fraction of epileptic pathologies, additional therapeutic options are needed. We report the successful treatment of dominant insular epilepsy in a 53-year-old male with minimally invasive laser ablation complicated by mild verbal and memory deficits. We also report neuropsychological test data on this patient before surgery and at 8 months after the ablation procedure. This account represents the first reported successful patient outcome of laser ablation as an effective treatment option for medically refractory post-stroke epilepsy in an adult. © 2014 S. Karger AG, Basel.
    Stereotactic and Functional Neurosurgery 10/2014; 92(6):397-404. DOI:10.1159/000366001 · 1.48 Impact Factor
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    ABSTRACT: Results from a previously conducted global phase III study (PREVAIL; NCT01142193) demonstrate the safety and efficacy of once-daily USL255, Qudexy™ XR (topiramate) extended-release capsules, as adjunctive treatment of drug-resistant partial-onset seizures (POSs). In this study, we report a post hoc analysis of PREVAIL data according to patient level of treatment resistance (based upon the number of concomitant antiepileptic drugs [AEDs] and lifetime AEDs) at baseline, with patients defined as either having “highly” drug-resistant seizures (≥ 2 concurrent AEDs and ≥ 4 lifetime AEDs) or having “less” drug-resistant seizures (1 concurrent AED or < 4 lifetime AEDs) at baseline. For each subgroup, median percent reduction in POS frequency (primary endpoint), responder rate, Clinical Global Impression of Change (CGI-C), and Quality of Life in Epilepsy — Problems (QOLIE-31-P) survey were assessed. Of 249 PREVAIL patients, 115 were classified as having highly drug-resistant seizures (USL255: n = 52, placebo: n = 63), and 134 were classified as having less drug-resistant seizures (USL255: n = 72, placebo: n = 62) at baseline. For the primary endpoint, USL255 resulted in significantly better seizure outcomes compared with placebo regardless of drug-resistant status (P = .004 and P = .040 for “highly” and “less”, respectively). Responder rate was also significantly improved in patients with highly drug-resistant group (P = .023). The CGI-C scores indicated significant improvement in both subgroups (P = .003 and P = .013 for “highly” and “less”, respectively). On the QOLIE-31-P, a significant improvement on the seizure worry subscale for the group with less drug-resistant seizures was noted in USL255-treated patients compared with placebo-treated patients (P = .003); the overall score and all other subscales were not significantly different for both subgroups. We conclude that USL255 led to significant improvements across multiple outcomes compared with placebo, including in those patients with highly drug-resistant seizures to prior treatment, making it a valuable treatment option for patients with epilepsy.
    Epilepsy & Behavior 10/2014; 41:136–139. DOI:10.1016/j.yebeh.2014.09.061 · 2.06 Impact Factor
  • R Edward Hogan, Emily D Moseley, Luigi Maccotta
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    ABSTRACT: To demonstrate the accuracy across different acquisition and analysis methods, we evaluated the variability in hippocampal volumetric and surface displacement measurements resulting from two different MRI (magnetic resonance imaging) acquisition protocols.
    Journal of neuroimaging: official journal of the American Society of Neuroimaging 06/2014; 25(3). DOI:10.1111/jon.12135 · 1.82 Impact Factor
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    ABSTRACT: Objective To evaluate the efficacy and safety of USL255, Qudexy™ XR (topiramate) extended-release capsules, as an adjunctive treatment for refractory partial-onset seizures (POS) in adults taking one to three concomitant antiepileptic drugs.Methods In this global phase III study (PREVAIL; NCT01142193), 249 adults with POS were randomized 1:1 to once-daily USL255 (200 mg/day) or placebo. The primary and key secondary efficacy endpoints were median percent reduction in weekly POS frequency and responder rate (proportion of patients with ≥50% reduction in seizure frequency). Seizure freedom was also assessed. Safety (adverse events, clinical and laboratory findings), as well as treatment effects on quality of life (QOLIE-31-P) and clinical global impression of change (CGI-C), were evaluated.ResultsAcross the entire 11-week treatment phase, USL255 significantly reduced the median percent seizure frequency and significantly improved responder rate compared with placebo. Efficacy over placebo was observed early in treatment, in patients with highly refractory POS, and in those with the most debilitating seizure types (i.e., complex partial, partial secondarily generalized). USL255 was safe and generally well tolerated with a low incidence of neurocognitive adverse events. USL255 was associated with significant clinical improvement without adversely affecting quality of life.SignificanceThe PREVAIL phase III clinical study demonstrated that once-daily USL255 (200 mg/day) significantly improved seizure control and was safe and generally well tolerated with few neurocognitive side effects.
    Epilepsia 06/2014; 55(7). DOI:10.1111/epi.12660 · 4.58 Impact Factor
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    ABSTRACT: How epilepsy affects brain functional networks remains poorly understood. Here we investigated resting state functional connectivity of the temporal region in temporal lobe epilepsy. Thirty-two patients with unilateral temporal lobe epilepsy underwent resting state blood-oxygenation level dependent functional magnetic resonance imaging. We defined regions of interest a priori focusing on structures involved, either structurally or metabolically, in temporal lobe epilepsy. These structures were identified in each patient based on their individual anatomy. Our principal findings are decreased local and inter-hemispheric functional connectivity and increased intra-hemispheric functional connectivity ipsilateral to the seizure focus compared to normal controls. Specifically, several regions in the affected temporal lobe showed increased functional coupling with the ipsilateral insula and immediately neighboring subcortical regions. Additionally there was significantly decreased functional connectivity between regions in the affected temporal lobe and their contralateral homologous counterparts. Intriguingly, decreased local and inter-hemispheric connectivity was not limited or even maximal for the hippocampus or medial temporal region, which is the typical seizure onset region. Rather it also involved several regions in temporal neo-cortex, while also retaining specificity, with neighboring regions such as the amygdala remaining unaffected. These findings support a view of temporal lobe epilepsy as a disease of a complex functional network, with alterations that extend well beyond the seizure onset area, and the specificity of the observed connectivity changes suggests the possibility of a functional imaging biomarker for temporal lobe epilepsy.
    12/2013; 2:862-72. DOI:10.1016/j.nicl.2013.06.011
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    ABSTRACT: Recent advances in basic neuroscience research across a wide range of methodologies have contributed significantly to our understanding of human cortical electrophysiology and functional brain imaging. Translation of this research into clinical neurosurgery has opened doors for advanced mapping of functionality that previously was prohibitively difficult, if not impossible. Here we present the case of a unique individual with congenital blindness and medically refractory epilepsy who underwent neurosurgical treatment of her seizures. Pre-operative evaluation presented the challenge of accurately and robustly mapping the cerebral cortex for an individual with a high probability of significant cortical re-organization. Additionally, a blind individual has unique priorities in one's ability to read Braille by touch and sense the environment primarily by sound than the non-vision impaired person. For these reasons we employed additional measures to map sensory, motor, speech, language, and auditory perception by employing a number of cortical electrophysiologic mapping and functional magnetic resonance imaging methods. Our data show promising results in the application of these adjunctive methods in the pre-operative mapping of otherwise difficult to localize, and highly variable, functional cortical areas.
    Frontiers in Human Neuroscience 07/2013; 7:431. DOI:10.3389/fnhum.2013.00431 · 2.90 Impact Factor
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    ABSTRACT: PURPOSE: Posttraumatic epilepsy (PTE) occurs in a proportion of traumatic brain injury (TBI) cases, significantly compounding the disability, and risk of injury and death for sufferers. To date, predictive biomarkers for PTE have not been identified. This study used the lateral fluid percussion injury (LFPI) rat model of TBI to investigate whether structural, functional, and behavioral changes post-TBI relate to the later development of PTE. METHODS: Adult male Wistar rats underwent LFPI or sham injury. Serial magnetic resonance (MR) and positron emission tomography (PET) imaging, and behavioral analyses were performed over 6 months postinjury. Rats were then implanted with recording electrodes and monitored for two consecutive weeks using video-electroencephalography (EEG) to assess for PTE. Of the LFPI rats, 52% (n = 12) displayed spontaneous recurring seizures and/or epileptic discharges on the video-EEG recordings. KEY FINDINGS: MRI volumetric and signal analysis of changes in cortex, hippocampus, thalamus, and amygdala, (18) F-fluorodeoxyglucose (FDG)-PET analysis of metabolic function, and behavioral analysis of cognitive and emotional changes, at 1 week, and 1, 3, and 6 months post-LFPI, all failed to identify significant differences on univariate analysis between the epileptic and nonepileptic groups. However, hippocampal surface shape analysis using large-deformation high-dimensional mapping identified significant changes in the ipsilateral hippocampus at 1 week postinjury relative to baseline that differed between rats that would go onto become epileptic versus those who did not. Furthermore, a multivariate logistic regression model that incorporated the 1 week, and 1 and 3 month (18) F-FDG PET parameters from the ipsilateral hippocampus was able to correctly predict the epileptic outcome in all of the LFPI cases. As such, these subtle changes in the ipsilateral hippocampus at acute phases after LFPI may be related to PTE and require further examination. SIGNIFICANCE: These findings suggest that PTE may be independent of major structural, functional, and behavioral changes induced by TBI, and suggest that more subtle abnormalities are likely involved. However, there are limitations associated with studying acquired epilepsies in animal models that must be considered when interpreting these results, in particular the failure to detect differences between the groups may be related to the limitations of properly identifying/separating the epileptic and nonepileptic animals into the correct group.
    Epilepsia 05/2013; 54(7). DOI:10.1111/epi.12223 · 4.58 Impact Factor
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    ABSTRACT: OBJECTIVE: Selective amygdalohippocampectomy (AHC) has evolved to encompass a variety of techniques to resect the mesial temporal lobe. To date, there have been few large-scale evaluations of trans-middle temporal gyrus selective AHC. The authors examine a large series of patients who have undergone the trans-middle temporal gyrus AHC and assess its clinical and neuropsychological impact. METHODS: A series of 76 adult patients underwent selective AHC via the trans-middle temporal gyrus approach over a 10-year period, 19 of whom underwent pre- and postoperative neuropsychological evaluations. RESULTS: Favorable seizure response rates were achieved (92% Engel class I or II), with very low surgical morbidity and no mortality. Postoperative neuropsychological assessment revealed a decline in verbal memory for the left AHC group. No postoperative memory decline was identified for the right AHC group, but rather some improvements were noted within this group. CONCLUSIONS: The trans-middle temporal gyrus selective AHC is a safe and effective choice for management of medically refractory epilepsy in adults.
    Epilepsy & Behavior 05/2013; 28(1):17-21. DOI:10.1016/j.yebeh.2013.03.020 · 2.06 Impact Factor
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    ABSTRACT: Structural hippocampal magnetic resonance (MR) imaging-based analysis is helpful in the diagnosis and treatment of mesial temporal epileptic seizures. Computational anatomic techniques provide a framework for objective assessment of three-dimensional hippocampal structure. We applied a previously validated technique of deformation-based hippocampal segmentations in 20 subjects with documented unilateral mesial temporal sclerosis (MTS) and temporal lobe epilepsy. Using composite images, we then measured shape differences between the epileptogenic, smaller hippocampus, and contralateral hippocampus. Final shape differences were projected on the contralateral “normal” side. We calculated results for the left MTS group (10 patients) and right MTS group (10 patients) separately. Both groups showed similar regions of maximal inward deformation in the affected hippocampus, which were the medical and lateral aspect of the head, and posterior aspect of the tail. These results suggest that there are specific three-dimensional patterns of volume loss in patients with mesial temporal epilepsy.
    Journal of Digital Imaging 04/2012; 13:39-42. DOI:10.1007/BF03167621 · 1.20 Impact Factor
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    ABSTRACT: The emerging insight into resting-state cortical networks has been important in our understanding of the fundamental architecture of brain organization. These networks, which were originally identified with functional magnetic resonance imaging, are also seen in the correlation topography of the infraslow rhythms of local field potentials. Because of the fundamental nature of these networks and their independence from task-related activations, we posit that, in addition to their neuroscientific relevance, these slow cortical potential networks could play an important role in clinical brain mapping. To assess whether these networks would be useful in identifying eloquent cortex such as sensorimotor cortex in patients both awake and under anesthesia. This study included 9 subjects undergoing surgical treatment for intractable epilepsy. Slow cortical potentials were recorded from the cortical surface in patients while awake and under propofol anesthesia. To test brain-mapping utility, slow cortical potential networks were identified with data-driven (seed-independent) and anatomy-driven (seed-based) approaches. With electrocortical stimulation used as the gold standard for comparison, the sensitivity and specificity of these networks for identifying sensorimotor cortex were calculated. Networks identified with a data-driven approach in patients under anesthesia and awake were 90% and 93% sensitive and 58% and 55% specific for sensorimotor cortex, respectively. Networks identified with systematic seed selection in patients under anesthesia and awake were 78% and 83% sensitive and 67% and 60% specific, respectively. Resting-state networks may be useful for tailoring stimulation mapping and could provide a means of identifying eloquent regions in patients while under anesthesia.
    Neurosurgery 04/2012; 71(2):305-16; discussion 316. DOI:10.1227/NEU.0b013e318258e5d1 · 3.03 Impact Factor
  • R Edward Hogan
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    ABSTRACT: With advances in technological innovation, electroencephalography has remained the gold standard for classification and localization of epileptic seizures. Like other diagnostic modalities, technological advances have opened new avenues for assessment of data, and hold great promise to improve interpretive capabilities. However, proper overall interpretation and application of electroencephalographic findings relies on valid correlations of associated clinical semiology. This article addresses interpretation of clinical signs and symptoms in the context of the diagnostic predictive value of electroencephalographic, clinical, and electrographic definitions of seizures, and upcoming challenges of interpreting intracranial high-frequency electroencephalographic data. This article is part of a Supplemental Special Issue entitled The Future of Automated Seizure Detection and Prediction.
    Epilepsy & Behavior 12/2011; 22 Suppl 1:S4-6. DOI:10.1016/j.yebeh.2011.08.021 · 2.06 Impact Factor
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    ABSTRACT: Controlled-release formulations of Valproate (VPA) reduce side effects by minimizing peak plasma VPA concentrations in patients with epilepsy. However, the impact of this on anti-seizure efficacy has not been thoroughly explored. Here the pharmacokinetics and pharmacodynamics of chronic intermittent (consequently, peak VPA concentrations) and continuous VPA administration were directly compared in two rat models of epilepsy. Genetic Absence Epilepsy Rats from Strasbourg (GAERS) received a single acute bolus of VPA (100 mg/kg intravenously) combined with electroencephalography (EEG) and/or blood sampling for 180 min post-injection. GAERS and epileptic rats post-kainic acid-induced status epilepticus were chronically infused intravenously (3-5 days, respectively) with (i) saline followed by in random order (ii) intermittent and (iii) continuous VPA (42 mg/kg/h), separated by two days of wash-out. Seizures were quantified using video-EEG monitoring and VPA levels measured in brain, cerebrospinal fluid and plasma. Following acute VPA administration seizure suppression in GAERS persisted after plasma VPA levels became very low. Chronic intermittent and continuous VPA significantly suppressed seizures in both models (p<0.01) with no difference between administration regimens. In GAERS, the pattern of seizure suppression during intermittent treatment was constant, in contrast to the fluctuating VPA plasma and brain levels. There was discordance between the temporal pattern of plasma, brain VPA levels and seizure suppression efficacy in GAERS. Administration regimes that result in fluctuating VPA blood levels achieve equivalent sustained seizure suppression as those that maintain steady mid-range concentrations.
    Seizure 01/2011; 20(1):72-9. DOI:10.1016/j.seizure.2010.10.011 · 2.06 Impact Factor
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    ABSTRACT: Traumatic brain injury (TBI) has a high incidence of long-term neurologic and neuropsychiatric morbidity. Metabolic and structural changes in rat brains were assessed after TBI using serial (18)F-FDG PET and 3-dimensional MRI in vivo. Rats underwent lateral fluid percussion injury (FPI; n = 16) or a sham procedure (n = 11). PET and MR images were acquired at 1 wk and at 1, 3, and 6 mo after injury. Morphologic changes were assessed using MRI-based regions of interest, and hippocampal shape changes were assessed with large-deformation high-dimensional mapping. Metabolic changes were assessed using region-of-interest analysis and statistical parametric mapping with the flexible factorial analysis. Anxiety-like behavior and learning were assessed at 1, 3, and 6 mo after injury. PET analyses showed widespread hypometabolism in injured rats, in particular involving the ipsilateral cortex, hippocampus, and amygdalae, present at 1 wk after FPI, most prominent at 1 mo, and then decreasing. Compared with the sham group, rats in the FPI group had decreased structural volume which progressively increased over 3-6 mo, occurring in the ipsilateral cortex, hippocampus, and ventricles after FPI (P < 0.05). Large-deformation high-dimensional mapping showed evolving hippocampal shape changes across the 6 mo after FPI. Injured rats displayed increased anxiety-like behavior (P < 0.05), but there were no direct correlations between the severity of the behavior abnormalities and functional or structural imaging changes. In selected brain structures, FPI induces early hypometabolism and delayed progressive atrophic changes that are dynamic and continue to evolve for months. These findings have implications for the understanding of the pathophysiology and evolution of long-term neurologic morbidity following TBI, and indicate an extended window for targeted neuroprotective interventions.
    Journal of Nuclear Medicine 11/2010; 51(11):1788-95. DOI:10.2967/jnumed.110.078626 · 5.56 Impact Factor
  • Injury 07/2010; 41. DOI:10.1016/j.injury.2010.01.073 · 2.46 Impact Factor
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    ABSTRACT: To report the detection of structural and functional biological changes in living animals using small animal in vivo MRI that complements traditional ex vivo histological techniques. We report the development and validation of the application of large deformation high dimensional mapping (HDM-LD) segmentation for the hippocampus in the rat. High resolution volumetric T2 weighted MRI images were acquired at 4.7 Tesla from six male in-breed nonepileptic Wistar rats. Two HDM-LD segmentations of the hippocampus (automated 1 and automated 2) were compared with the manual segmentations of two investigators who independently segmented the hippocampi (manual 1 and manual 2). The mean overlap for the hippocampi between automated 1 and automated 2 for the right hippocampi was 94.4% (SD 1.0) and for the left hippocampi was 94.3% (SD 2.5), while the mean overlap between automated 1 and manual 1 for the right hippocampi was 91.4% (SD 1.3) and for the left hippocampi was 91.9% (SD 1.4). Mean values for absolute differences for comparisons of all the segmentations were the following: automated 1 versus automated 2, 3.2% (SD 1.0); manual 1 versus manual 2 6.82% (SD 5.22); automated 1 versus manual 1 13.0% (SD 1.8). HDM-LD can be applied to obtain accurate and reproducible three-dimensional segmentations of the hippocampus from rat MR images. HDM-LD will be a useful tool for investigations of hippocampal structural changes in vivo in rat models of human disease.
    Journal of Magnetic Resonance Imaging 05/2009; 29(5):1027-34. DOI:10.1002/jmri.21766 · 2.79 Impact Factor
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    ABSTRACT: Imaging studies of epilepsy patients with comorbid affective disturbance demonstrate morphometric changes in limbic brain regions implicated in psychiatric disease. Genetic Absence Epilepsy Rats from Strasbourg (GAERS), specifically bred for their epilepsy phenotype, also exhibit elevated anxiety-like behaviors suggesting a common causality. Here we examined whether relevant cerebral morphological alterations exist in this rat strain using volumetric measurements and large deformation high dimensional mapping (HDM-LD), a tool recently validated to produce accurate three-dimensional surface representations of the hippocampus. Volumetric MRI and the Open Field test of anxiety were performed in adult female GAERS (n=12) and Non-Epileptic Controls (NEC; n=11). The volumes of selected brain regions, including cortex, hippocampus, amygdala, thalamus, hypothalamus and lateral ventricles, were measured using Region-Of-Interest analysis from the MRI data and total volumes compared between the two strains. GAERS had increased amygdala (right: p=0.003; left p<0.001), cortices (right: p=0.006; left p=0.012) and ventricular volumes (p=0.002) when compared with NEC rats. Further, HDM-LD showed GAERS to have hippocampal volume loss in two regions: the medial hippocampal surface immediately caudal to the hippocampal commissure, and the lateral hippocampal surface over the mid-portion of the septotemporal axis. GAERS exhibited increased anxiety in the Open Field compared with NEC rats: reduced distance traveled (p<0.001) and reduced time in the centre area (p=0.042). Morphometric brain changes in GAERS could be relevant to their hyperanxious and epileptic phenotypes. This model may be useful in illuminating the pathogenesis of affective disorders generally, as well as modeling psychiatric comorbidities of epilepsy.
    NeuroImage 12/2008; 45(2):267-74. DOI:10.1016/j.neuroimage.2008.12.019 · 6.13 Impact Factor
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    ABSTRACT: To compare hippocampal surface structure, using large deformation high dimensional mapping (HDM-LD), in subjects with temporal lobe epilepsy (TLE) with (HS+ve) and without (HS-ve) hippocampal sclerosis. The study included 30 HS-ve subjects matched with 30 HS+ve subjects from the previously reported epilepsy patient cohort. To control for normal right-left asymmetries of hippocampal surface structure, subjects were regrouped based on laterality of onset of epileptic seizures and presence of HS. Gender ratio, age, duration of epilepsy and seizure frequency were calculated for each of the four groups. Final HDM-LD surface maps of the right and left TLE groups were compared to define differences in subregional hippocampal involvement within the groups. There were no significant differences in comparisons of the left TLE (left HS-ve compared with HS+ve) or right TLE (right HS-ve compared with HS+ve) groups with respect to age, duration of epilepsy or seizure severity scores. HDM-LD maps showed accentuated surface changes over the lateral hippocampal surface, in the region of the Sommer sector, in the hippocampi affected by HS. However, HS-ve hippocampi showed maximal surface changes in a different pattern, and did not involve the region of Sommer sector. We conclude that differences in segmental volume loss between the HS-ve and HS+ve groups are suggestive that the underlying pathophysiology of hippocampal changes in the two groups is different, and not related to chronic seizure duration or severity.
    Journal of neurology, neurosurgery, and psychiatry 07/2008; 79(6):636-40. DOI:10.1136/jnnp.2007.123406 · 5.58 Impact Factor

Publication Stats

509 Citations
169.30 Total Impact Points

Institutions

  • 2003–2015
    • Washington University in St. Louis
      • Department of Neurology
      San Luis, Missouri, United States
  • 1999–2012
    • Saint Louis University
      • • Department of Neurosurgery
      • • Division of Nephrology
      Saint Louis, Michigan, United States
  • 2004–2006
    • University of California, San Francisco
      San Francisco, California, United States
  • 1996–1997
    • Royal Melbourne Hospital
      • Department of Radiology
      Melbourne, Victoria, Australia