Home video prediction of epileptic vs. nonepileptic seizures in US veterans.

OBJECTIVE: Using video-EEG (v-EEG) diagnosis as a gold standard, we assessed the predictive diagnostic value of home videos of spells with or without additional limited demographic data in US veterans referred for evaluation of epilepsy. Veterans, in particular, stand to benefit from improved diagnostic tools given higher rates of PNES and limited accessibility to care. METHODS: This was a prospective, blinded diagnostic accuracy study in adults conducted at the Houston VA Medical Center from 12/2015-06/2019. Patients with a definitive diagnosis of epileptic seizures (ES), psychogenic nonepileptic seizures (PNES), or physiologic nonepileptic events (PhysNEE) from v-EEG monitoring were asked to submit home videos. Four board-certified epileptologists blinded to the original diagnosis formulated a diagnostic impression based upon the home video review alone and video plus limited demographic data. RESULTS: Fifty patients (30 males; mean age 47.7 years) submitted home videos. Of these, 14 had ES, 33 had PNES, and three had PhysNEE diagnosed by v-EEG. The diagnostic accuracy by video alone was 88.0%, with a sensitivity of 83.9% and specificity of 89.6%. Providing raters with basic patient demographic information in addition to the home videos did not significantly improve diagnostic accuracy when comparing to reviewing the videos alone. Inter-rater agreement between four raters based on video was moderate with both videos alone (kappa = 0.59) and video plus limited demographic data (kappa = 0.60). SIGNIFICANCE: This study demonstrated that home videos of paroxysmal events could be an important tool in reliably diagnosing ES vs. PNES in veterans referred for evaluation of epilepsy when interpreted by experts. A moderate inter-rater reliability was observed in this study.

Accuracy and Workflow Improvements for Responsive Neurostimulation Hippocampal Depth Electrode Placement Using Robotic Stereotaxy.

Background: Robotic stereotaxy is increasingly common in epilepsy surgery for the implantation of stereo-electroencephalography (sEEG) electrodes for intracranial seizure monitoring. The use of robots is also gaining popularity for permanent stereotactic lead implantation applications such as in deep brain stimulation and responsive neurostimulation (RNS) procedures. Objective: We describe the evolution of our robotic stereotactic implantation technique for placement of occipital-approach hippocampal RNS depth leads. Methods: We performed a retrospective review of 10 consecutive patients who underwent robotic RNS hippocampal depth electrode implantation. Accuracy of depth lead implantation was measured by registering intraoperative post-implantation fluoroscopic CT images and post-operative CT scans with the stereotactic plan to measure implantation accuracy. Seizure data were also collected from the RNS devices and analyzed to obtain initial seizure control outcome estimates. Results: Ten patients underwent occipital-approach hippocampal RNS depth electrode placement for medically refractory epilepsy. A total of 18 depth electrodes were included in the analysis. Six patients (10 electrodes) were implanted in the supine position, with mean target radial error of 1.9 ± 0.9 mm (mean ± SD). Four patients (8 electrodes) were implanted in the prone position, with mean radial error of 0.8 ± 0.3 mm. The radial error was significantly smaller when electrodes were implanted in the prone position compared to the supine position (p = 0.002). Early results (median follow-up time 7.4 months) demonstrate mean seizure frequency reduction of 26% (n = 8), with 37.5% achieving ≥50% reduction in seizure frequency as measured by RNS long episode counts. Conclusion: Prone positioning for robotic implantation of occipital-approach hippocampal RNS depth electrodes led to lower radial target error compared to supine positioning. The robotic platform offers a number of workflow advantages over traditional frame-based approaches, including parallel rather than serial operation in a bilateral case, decreased concern regarding human error in setting frame coordinates, and surgeon comfort.

A somatic mutation in MEN1 gene detected in periventricular nodular heterotopia tissue obtained from depth electrodes.

Periventricular nodular heterotopia (PNH) is a common structural malformation of cortical development. Mutations in the filamin A gene are frequent in familial cases with X-linked PNH. However, many cases with sporadic PNH remain genetically unexplained. Although medically refractory epilepsy often brings attention to the underlying PNH, patients are often not candidates for surgical resection. This limits access to neuronal tissue harboring causal mutations. We evaluated a patient with PNH and medically refractory focal epilepsy who underwent a presurgical evaluation with stereotactically placed electroencephalographic (SEEG) depth electrodes. Following SEEG explantation, we collected trace tissue adherent to the electrodes and extracted the DNA. Whole-exome sequencing performed in a Clinical Laboratory Improvement Amendments-approved genetic diagnostic laboratory uncovered a de novo heterozygous pathogenic variant in novel candidate PNH gene MEN1 (multiple endocrine neoplasia type 1; c.1546dupC, p.R516PfsX15). The variant was absent in an earlier exome profiling of the venous blood-derived DNA. The MEN1 gene encodes the ubiquitously expressed, nuclear scaffold protein menin, a known tumor suppressor gene with an established role in the regulation of transcription, proliferation, differentiation, and genomic integrity. Our study contributes a novel candidate gene in PNH generation and a novel practical approach that integrates electrophysiological and genetic explorations of epilepsy.

Treatment of drug-resistant epilepsy in patients with periventricular nodular heterotopia using RNS® System: Efficacy and description of chronic electrophysiological recordings.

OBJECTIVES: Describe changes in clinical seizure frequency and electrophysiological data recorded in patients with medically-intractable seizures and periventricular nodular heterotopias (PVNH) treated with the RNS® System (NeuroPace, Inc., Mountain View, CA). METHODS: Clinical seizures from eight patients (mean follow-up of 10.1 years) were analyzed pre- and post-treatment. Chronic ambulatory electrocorticograms (ECoGs) recorded from PVNHs, hippocampus and neocortex were evaluated to identify the earliest electrographic seizure onset type, pattern of spread, and interictal characteristics. RESULTS: Mean reduction in disabling seizures was 85.7 % (n = 8); seven patients had >50% seizure reduction and two were seizure-free in the final year of analysis. Seizure rate showed a progressive reduction over the course of the study with the highest rate of improvement in the first two to three years after implantation. Four of seven patients with one PVNH lead and a second lead in the hippocampus or neocortex had some electrographic seizures first recorded at either lead location, suggesting two foci or seizure propagation patterns. Low voltage fast type activity was the prominent seizure onset pattern. Interictal ECoG power was lower in PVNH than hippocampus. CONCLUSIONS: RNS® System treatment substantially reduced clinical seizure frequency in patients with PVNH. Analysis of ictal ECoG records suggests PVNH may be involved in seizure generation. SIGNIFICANCE: Chronic ECoG recordings suggest PVNH tissue can actively participate in epileptogenic networks. Direct brain-responsive neurostimulation is a safe and effective treatment option in such patients, progressively reducing seizure rate over a period of years.

Are Seizure Detection Devices Ready for Prime Time?

Standards for testing and clinical validation of seizure detection Beniczky S, Ryvlin P. Epilepsia. 2018;59(S1):9-13. https://doi.org/10.1111/epi.14049 To increase the quality of studies on seizure detection devices, we propose standards for testing and clinical validation of such devices. We identified 4 key features that are important for studies on seizure detection devices: subjects, recordings, data analysis and alarms, and reference standard. For each of these features, we list the specific aspects that need to be addressed in the studies, and depending on these, studies are classified into 5 phases (0-4). We propose a set of outcome measures that need to be reported, and we propose standards for reporting the results. These standards will help in designing and reporting studies on seizure detection devices, they will give readers clear information on the level of evidence provided by the studies, and they will help regulatory bodies in assessing the quality of the validation studies. These standards are flexible, allowing classification of the studies into one of the 5 phases. We propose actions that can facilitate development of novel methods and devices. User-based evaluation of applicability and usability of a wearable accelerometer device for detecting bilateral tonic-clonic seizures: a field study Meritam P, Ryvlin P, Beniczky S. Epilepsia. 2018;59(S1):48-52. https://doi.org/10.1111/epi.14051 Clinical validation studies of seizure detection devices conducted in epilepsy monitoring units (EMUs) can be biased by the artificial environment. We report a field (phase 4) study of a wearable accelerometer device (Epi-Care) that has previously been validated in EMUs for detecting bilateral tonic-clonic seizures (BTCS). Seventy-one patients using the device (or their caregivers) completed the modified Post-Study System Usability Questionnaire. Median time patients had been using the device was 15 months (range = 24 days to 6 years). In 10% of cases, patients stopped using the device due to reasons related to the device. The median sensitivity (90%) and false alarm rate (0.1/day) were similar to what had been determined in EMUs. Patients and caregivers were overall satisfied with the device (median = 5.5 on the 7-point Likert scale), considered the technical aspects satisfactory, and considered the device comfortable and efficient. Adverse effects occurred in 11% but were only mild: skin irritation at the wrist and interference with home electronic appliances. In 55%, the device influenced the number of seizures logged into the seizure diary, and in 40%, it contributed to fewer seizure-related injuries. This field study demonstrates the applicability and usability of the wearable accelerometer device for detecting BTCS. Wearable devices for sudden unexpected death in epilepsy prevention Ryvlin P, Ciumas C, Wisniewski I, Beniczky S. Epilepsia. 2018;59(S1):61-66. https://doi.org/10.1111/epi.14054 Sudden unexpected death in epilepsy (SUDEP) is most often associated with the occurrence of generalized tonic-clonic seizures (GTCS), a seizure type that can now be detected with high sensitivity and specificity by wearable or bed devices. The recent development in such devices and their performance offer multiple opportunities to tackle SUDEP and its prevention. Reliable GTCS detection might help physicians optimize antiepileptic treatment, which could in turn reduce the risk of SUDEP. Generalized tonic-clonic seizures-triggered alarms can lead to immediate intervention by caregivers that are also likely to decrease the odd of SUDEP. The biosignals used to detect GTCS might provide novel SUDEP biomarkers, in particular, by informing on several important characteristics of the ictal and postictal periods (type of GTCS, duration of tonic phase, rotation in the prone position, presence and duration of postictal immobility and bradycardia, rise in electrodermal activity). Other biosensors not yet used for detecting GTCS might provide complementary information, such as the presence and intensity of ictal/postictal hypoxemia. The above biomarkers, if strongly predictive, could help identify patients at very high risk of SUDEP, enabling better assessment of individual risk, as well as selection of appropriate patients for clinical studies aiming at preventing SUDEP. The same biosignals could also be used as ancillary biomarkers to test the impact of various interventions before moving to highly challenging randomized controlled trials with SUDEP as a primary outcome.

Sudden unexpected death in epilepsy in patients treated with brain-responsive neurostimulation.

OBJECTIVE: To study the incidence and clinical features of sudden unexpected death in epilepsy (SUDEP) in patients treated with direct brain-responsive stimulation with the RNS System. METHODS: All deaths in patients treated in clinical trials (N = 256) or following U.S. Food and Drug Administration (FDA) approval (N = 451) through May 5, 2016, were adjudicated for SUDEP. RESULTS: There were 14 deaths among 707 patients (2208 postimplantation years), including 2 possible, 1 probable, and 4 definite SUDEP events. The rate of probable or definite SUDEP was 2.0/1000 (95% confidence interval [CI] 0.7-5.2) over 2036 patient stimulation years and 2.3/1000 (95% CI 0.9-5.4) over 2208 patient implant years. Stored electrocorticograms around the time of death were available for 4 patients with probable/definite SUDEP and revealed the following: frequent epileptiform activity ending abruptly (n = 2), no epileptiform activity or seizures (n = 1), and an electrographic and witnessed seizure with cessation of postictal electrocorticography (ECoG) activity associated with apnea and pulselessness (n = 1). SIGNIFICANCE: The SUDEP rate of 2.0/1000 patient stimulation years among patients treated with the RNS System is favorable relative to treatment-resistant epilepsy patients randomized to the placebo arm of add-on drug studies or with seizures after resective surgery. Our findings support that treatments that reduce seizures reduce SUDEP risk and that not all SUDEPs follow seizures.

Brain-responsive neurostimulation in patients with medically intractable mesial temporal lobe epilepsy.

OBJECTIVE: Evaluate the seizure-reduction response and safety of mesial temporal lobe (MTL) brain-responsive stimulation in adults with medically intractable partial-onset seizures of mesial temporal lobe origin. METHODS: Subjects with mesial temporal lobe epilepsy (MTLE) were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline. Safety was assessed based on reported adverse events. RESULTS: There were 111 subjects with MTLE; 72% of subjects had bilateral MTL onsets and 28% had unilateral onsets. Subjects had one to four leads placed; only two leads could be connected to the device. Seventy-six subjects had depth leads only, 29 had both depth and strip leads, and 6 had only strip leads. The mean follow-up was 6.1 ± (standard deviation) 2.2 years. The median percent seizure reduction was 70% (last observation carried forward). Twenty-nine percent of subjects experienced at least one seizure-free period of 6 months or longer, and 15% experienced at least one seizure-free period of 1 year or longer. There was no difference in seizure reduction in subjects with and without mesial temporal sclerosis (MTS), bilateral MTL onsets, prior resection, prior intracranial monitoring, and prior vagus nerve stimulation. In addition, seizure reduction was not dependent on the location of depth leads relative to the hippocampus. The most frequent serious device-related adverse event was soft tissue implant-site infection (overall rate, including events categorized as device-related, uncertain, or not device-related: 0.03 per implant year, which is not greater than with other neurostimulation devices). SIGNIFICANCE: Brain-responsive stimulation represents a safe and effective treatment option for patients with medically intractable epilepsy, including patients with unilateral or bilateral MTLE who are not candidates for temporal lobectomy or who have failed a prior MTL resection.

Predictors of Postoperative Seizure Recurrence: A Longitudinal Study of Temporal and Extratemporal Resections.

Objective. We investigated the longitudinal outcome of resective epilepsy surgery to identify the predictors of seizure recurrence. Materials and Methods. We retrospectively analyzed patients who underwent resections for intractable epilepsy over a period of 7 years. Multiple variables were investigated as potential predictors of seizure recurrence. The time to first postoperative seizure was evaluated using survival analysis and univariate analysis at annual intervals. Results. Among 70 patients, 54 (77%) had temporal and 16 (23%) had extratemporal resections. At last follow-up (mean 48 months; range 24-87 months), the outcome was Engel class I in 84% (n = 59) of patients. Seizure recurrence followed two patterns: recurrence was "early" (within 2 years) in 82% of patients, of whom 83% continued to have seizures despite optimum medical therapy; recurrence was "late" (after 2 years) in 18%, of whom 25% continued to have seizures subsequently. Among the variables of interest, only resection site and ictal EEG remained as independent predictors of seizure recurrence over the long term (p < 0.05). Extratemporal resection and discordance between ictal EEG and resection area were associated with 4.2-fold and 5.6-fold higher risk of seizure recurrence, respectively. Conclusions. Extratemporal epilepsy and uncertainty in ictal EEG localization are independent predictors of unfavorable outcome. Seizure recurrence within two years of surgery indicates poor long-term outcome.

Retrospective case series of the clinical features, management and outcomes of patients with autoimmune epilepsy.

PURPOSE: Analyze clinical and electrographic characteristics of patients with autoimmune epilepsy, and evaluate the effect of early diagnosis and treatment on reduction of seizure frequency. METHODS: Observational retrospective case series, conducted using electronic medical data from two teaching hospitals. Clinical data was collected from 2008 to 2013. Cases of new onset seizures were selected based on the presence of laboratory evidence of autoimmunity. RESULTS: 34 hospitalized patients who presented predominantly due to seizures with concern for autoimmune etiology were identified. Mean age of patients was 44.94 years and 64.7% were males. Autoimmune antibodies were detected in 76.5% (26) of patients as follows: VGKc (8); NMDA-R (7); anti-thyroid (5); GAD (4); GABAB (2). 22 patients had unilateral temporal lobe onset and 4 had bilateral temporal lobe onset, while 8 had extra-temporal onset/multiple ictal foci. Median number of seizures during initial prolonged vEEG monitoring was 8 (range 0-48); median number of anti-seizure medications used was 2 (range 1-5). 9 patients had an underlying malignancy. 94.1% (32) patients received immunomodulation, as follows: high dose corticosteroids (96.8%), plasmapheresis (62.5%), IVIG (34.4%), rituximab (21.8%), mycophenolate (15.6%), cyclophosphamide (12.5%). 63.3% (19) participants achieved ≥ 50% seizure reduction (Responder Rate) at first clinic visit. Patients without malignancy had better seizure control (p < 0.05). Time from symptom onset to diagnosis (p < 0.005) and symptom onset to immunomodulation (p < 0.005) was significantly lower among patients who achieved responder rate (RR). CONCLUSION: This study highlights certain important clinical and electrographic aspects of autoimmune epilepsy, and the significance of early diagnosis and initiation of immunomodulatory therapy.

Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography.

OBJECTIVE: Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. METHODS: Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. RESULTS: Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. SIGNIFICANCE: About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions.

Subtypes of post-traumatic epilepsy: clinical, electrophysiological, and imaging features.

Post-traumatic epilepsy (PTE) is a consequence of traumatic brain injury (TBI), occurring in 10-25% of patients with moderate to severe injuries. The development of animal models for testing antiepileptogenic therapies and validation of biomarkers to follow epileptogenesis in humans necessitates sophisticated understanding of the subtypes of PTE, which is the objective of this study. In this study, retrospective review was performed of patients with moderate to severe TBI with subsequent development of medically refractory epilepsy referred for video-electroencephalography (EEG) monitoring at a single center over a 10-year period. Information regarding details of injury, neuroimaging studies, seizures, video-EEG, and surgery outcomes were collected and analyzed. There were 123 patients with PTE identified, representing 4.3% of all patients evaluated in the epilepsy monitoring unit. Most of them had localization-related epilepsy, of which 57% had temporal lobe epilepsy (TLE), 35% had frontal lobe epilepsy (FLE), and 3% each had parietal and occipital lobe epilepsy. Of patients with TLE, 44% had mesial temporal sclerosis (MTS), 26% had temporal neocortical lesions, and 30% were nonlesional. There was no difference in age at injury between the different PTE subtypes. Twenty-two patients, 13 of whom had MTS, proceeded to surgical resection. At a mean follow-up of 2.5 years, Engel Class I outcomes were seen in 69% of those with TLE and 33% of those with FLE. Our findings suggest PTE is a heterogeneous condition, and careful evaluation with video-EEG monitoring and high resolution MRI can identify distinct syndromes. These results have implications for the design of clinical trials of antiepileptogenic therapies for PTE.

Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial.

OBJECTIVE: To demonstrate the safety and effectiveness of responsive stimulation at the seizure focus as an adjunctive therapy to reduce the frequency of seizures in adults with medically intractable partial onset seizures arising from one or two seizure foci. METHODS: Randomized multicenter double-blinded controlled trial of responsive focal cortical stimulation (RNS System). Subjects with medically intractable partial onset seizures from one or two foci were implanted, and 1 month postimplant were randomized 1:1 to active or sham stimulation. After the fifth postimplant month, all subjects received responsive stimulation in an open label period (OLP) to complete 2 years of postimplant follow-up. RESULTS: All 191 subjects were randomized. The percent change in seizures at the end of the blinded period was -37.9% in the active and -17.3% in the sham stimulation group (p = 0.012, Generalized Estimating Equations). The median percent reduction in seizures in the OLP was 44% at 1 year and 53% at 2 years, which represents a progressive and significant improvement with time (p < 0.0001). The serious adverse event rate was not different between subjects receiving active and sham stimulation. Adverse events were consistent with the known risks of an implanted medical device, seizures, and of other epilepsy treatments. There were no adverse effects on neuropsychological function or mood. SIGNIFICANCE: Responsive stimulation to the seizure focus reduced the frequency of partial-onset seizures acutely, showed improving seizure reduction over time, was well tolerated, and was acceptably safe. The RNS System provides an additional treatment option for patients with medically intractable partial-onset seizures.

Cingulate epilepsy: report of 3 electroclinical subtypes with surgical outcomes.

IMPORTANCE: The literature on cingulate gyrus epilepsy in the magnetic resonance imaging era is limited to case reports and small case series. To our knowledge, this is the largest study of surgically confirmed epilepsy arising from the anterior or posterior cingulate region. OBJECTIVE: To characterize the clinical and electrophysiological findings of epilepsies arising from the anterior and posterior cingulate gyrus. DESIGN, SETTING, AND PARTICIPANTS: We studied consecutive cingulate gyrus epilepsy cases identified retrospectively from the Cleveland Clinic and University of Texas Southwestern Medical Center epilepsy databases from 1992 to 2009. Participants included 14 consecutive cases of cingulate gyrus epilepsies confirmed by restricted magnetic resonance image lesions and seizure freedom or marked improvement following lesionectomy. MAIN OUTCOMES AND MEASURES: The main outcome measure was improvement in seizure frequency following surgery. The clinical, video electroencephalography, neuroimaging, pathology, and surgical outcome data were reviewed. RESULTS: All 14 patients had cingulate epilepsy confirmed by restricted magnetic resonance image lesions and seizure freedom or marked improvement following lesionectomy. They were divided into 3 groups based on anatomical location of the lesion and corresponding seizure semiology. In the posterior cingulate group, all 4 patients had electroclinical findings suggestive of temporal origin of the epilepsy. The anterior cingulate cases were divided into a typical (Bancaud) group (6 cases with hypermotor seizures and infrequent generalization with the presence of fear, laughter, or severe interictal personality changes) and an atypical group (4 cases presenting with simple motor seizures and a tendency for more frequent generalization and less-favorable long-term surgical outcome). All atypical cases were associated with an underlying infiltrative astrocytoma. CONCLUSIONS AND RELEVANCE: Posterior cingulate gyrus epilepsy may present with electroclinical findings that are suggestive of temporal lobe epilepsy and can be considered as another example of pseudotemporal epilepsies. The electroclinical presentation and surgical outcome of lesional anterior cingulate epilepsy is possibly influenced by the underlying pathology. This study highlights the difficulty in localizing seizures arising from the cingulate gyrus in the absence of a magnetic resonance image lesion.

Cingulate gyrus epilepsy: clinical and behavioral aspects, with surgical outcomes.

BACKGROUND: Cingulate gyrus epilepsy is controversial because it may overlap with other frontal lobe epilepsy syndromes. Reported cases are rare in the pre-magnetic resonance imaging literature but are more common thereafter. Information about peri-ictal and ictal behaviors is scarce. OBJECTIVES: To characterize epilepsy originating from the cingulate gyrus and to report surgical outcomes. DESIGN: Case studies. SETTING: Academic research. PATIENTS: We report 3 surgically treated cases of cingulate gyrus epilepsy, with seizure-free or almost seizure-free outcomes. The cases were identified from a database of 4201 consecutive epilepsy monitoring unit admissions since October 1998 through September 2008. All 3 cases involved cingulate lesions. MAIN OUTCOME MEASURES: Neuroimaging, video electroencephalographic, pathologic, and surgical outcome data were reviewed. RESULTS: All 3 patients had lesional left anterocingulate seizures confirmed by magnetic resonance imaging and experienced cessation of seizures after lesionectomy. Two patients had auras (fear and laughter) previously associated with cingulate gyrus epilepsy. All patients had clinical features consistent with frontal lobe epilepsy, including hyperkinetic behavior and ictal vocalization. Two patients had behavioral changes with aggression, personality disorder, and poor judgment; some behavioral episodes lasted for days and were socially devastating. One patient, a commercial pilot, showed behavior as a passenger that resulted in a diversionary landing. The other patient demonstrated behavior that led to his arrest, and he was almost arrested again in the hospital for threatening security officers. Aberrant behaviors in all 3 patients completely resolved after lesionectomy. CONCLUSIONS: Lesional cingulate gyrus epilepsy is uncommon. Our 3 confirmed cases included 2 patients with unique and severe behavioral changes that resolved with lesionectomy.

Nephrolithiasis in topiramate users.

Topiramate is a neuromodulatory agent increasingly prescribed for a number of neurological and non-neurological indications. Topiramate-treated patients are at risk for nephrolithiasis due to hypocitraturia and high urine pH. However, the prevalence of symptomatic stone disease in TPM users is generally perceived to be low. This study was undertaken to assess in topiramate-treated patients the prevalence of symptomatic nephrolithiasis (by history) and of asymptomatic nephrolithiasis by computed tomography (CT) scan. Topiramate users were identified from a database of patients with neurological disorders at a single university hospital. Among 75 topiramate-treated adult patients with a median daily dose of 300 mg and median treatment duration of 48 months, the prevalence of symptomatic nephrolithiasis was 10.7%. In a subset of topiramate-treated patients and no history of symptomatic stone disease, the prevalence of asymptomatic nephrolithiasis detected by CT scan was 20%. The prevalence of symptomatic nephrolithiasis with long-term topiramate use is higher than reported in short-term studies. Furthermore, clinical prevalence is underestimated due to asymptomatic nephrolithiasis.

Posttraumatic epilepsy: the endophenotypes of a human model of epileptogenesis.

Posttraumatic epilepsy is a common complication of traumatic brain injury (TBI), occurring in up to 15-20% of patients with severe brain trauma. Trauma accounts for approximately 5% of chronic epilepsy in the community. Because it is a common condition, and because of the relatively short latency period between injury and onset of chronic seizures, posttraumatic epilepsy represents a good model to test antiepileptogenic therapies. However, several well-conducted clinical trials have failed to demonstrate antiepileptogenic efficacy for several common anticonvulsants. Posttraumatic epilepsy can arise through a number of mechanisms, which often coexist within a single patient. Penetrating brain injury produces a cicatrix in the cortex and is associated with a risk of posttraumatic epilepsy of approximately 50%, whereas nonpenetrating head injury may produce focal contusions and intracranial hemorrhages, and is associated with a risk of posttraumatic epilepsy of up to 30%. Furthermore, closed head injury often produces diffuse concussive injury, with shearing of axons and selective damage to vulnerable brain regions, such as the hippocampus. The clinical, neurophysiologic, imaging, and neuropathologic features or epileptogenicity differ between these alternate mechanisms. It is likely that better understanding of the subtypes of epilepsy resulting from brain trauma will be required to successfully identify antiepileptogenic therapies.