To evaluate the possibility of detecting fast ripples (FRs) on the surface EEG of patients with focal pharmacoresistant epilepsy, and to investigate the relationship between scalp FRs and ...localization of the seizure onset zone (SOZ). We included 10 patients undergoing combined surface–intracranial EEG with ≥10 spikes in the surface EEG during the first 30 consecutive minutes of N3 sleep. FRs (≥4 consecutive oscillations above 250 Hz with an amplitude clearly exceeding that of the background) on the surface EEG (F3-C3, C3-P3, Fz-Cz, Cz-Pz, F4-C4, C4-P4) were visually marked, and verified by two EEG experts. FRs were categorized as related to the SOZ, if localized in the brain lobe of the SOZ. Low-amplitude FRs with a rate of 0.09/min were found in 6/10 patients: two exhibited events related to the SOZ, three showed no relationship with the SOZ, and in one patient the SOZ was not identified. It may be possible to detect FRs with surface EEG using subdermal electrodes in patients with focal epilepsy. The relationship between surface FRs and the SOZ remains unclear. Future studies aiming at a higher spatial EEG coverage are needed to elucidate their significance.
Abstract Purpose We analyzed the association of granule cell dispersion (GCD) with memory performance, clinical data and surgical outcome in a series of patients with mesial temporal lobe epilepsy ...(MTLE) and mesial temporal sclerosis (MTS). Method Hippocampal specimens from 54 patients with MTLE (27 patients with right MTLE and 27 with left MTLE) and unilateral MTS, who were separated into GCD and no-GCD groups and thirteen controls were studied. Quantitative neuropathological evaluation was performed using hippocampal sections stained with NeuN. Patients’ neuropsychological measures, clinical data, type of MTS and surgical outcome were reviewed. Results GCD occurred in 28 (51.9%) patients. No correlation between GCD and MTS pattern, clinical data or surgical outcome was found. The presence of GCD was correlated with worse visuospatial memory performance in right MTLE, but not with memory performance in left MTLE. Conclusion GCD may be related to memory impairment in right MTLE-MTS patients. However, the role of GCD in memory function is not precisely defined.
Abstract We examined the relationship between presence and frequency of different types of auras and side of lesion and post surgical outcomes in 205 patients with medically intractable mesial ...temporal lobe epilepsy (MTLE) with unilateral hippocampal sclerosis (HS). With respect to the number of auras, multiple auras were not associated with side of lesion (p = 0.551). The side of HS was not associated with the type of auras reported. One hundred fifty-seven patients were operated. The occurrence of multiple auras was not associated with post-surgical outcome (p = 0.740). The presence of extratemporal auras was significantly higher in patients with poor outcome. In conclusion, this study suggests that the presence of extratemporal auras in patients with MTLE-HS possibly reflects extratemporal epileptogenicity in these patients, who otherwise showed features suggestive of TLE. Therefore, TLE-HS patients undergoing pre-surgical evaluation and presenting clinical symptoms suggestive of extratemporal involvement should be more extensively evaluated to avoid incomplete resection of the epileptogenic zone.
Purpose
Self-limited epilepsy with centrotemporal spikes, formerly called benign epilepsy with centrotemporal spikes, or rolandic epilepsy, is an age-related and well-defined epileptic syndrome. ...Since seizures associated with rolandic spikes are infrequent and usually occur during sleep, and repetitive or prolonged EEG recording for diagnostic purposes is not necessary for diagnosis, reports of ictal video-electroencephalographic seizures in this syndrome are rare. We aimed to show ictal video-EEG of typical rolandic seizures.
Methods
We report the ictal video-EEG recordings of two children with rolandic epilepsy who presented typical rolandic seizures during routine recording.
Results
Case 1: A 9-year-old boy, with normal development, had his first seizure at 8 years old, characterized by paresthesia in his left face, blocking of speech, and drooling. Carbamazepine was started with seizure control. Case 2: A 10-year-old boy, with normal development, started with focal seizures during sleep, characterized by eye and perioral deviation, and speech arrest at age of 7. He started using oxcarbazepine. Both patients underwent routine electroencephalography for electroclinical diagnosis and presented a seizure.
Conclusion
Although self-limited epilepsy with centrotemporal spikes is a very common epileptic syndrome, seizure visualization is very difficult, and these videos may bring didactical information for recognition of this usual presentation of benign childhood focal epilepsy.
•Scalp ripples can be used as an additional tool to lateralize the epileptic focus in secondary bilateral synchrony.•In idiopathic generalized epilepsy scalp ripples are recordable and show an ...anterior dominance.•To differentiate focal patients with secondary bilateral synchrony from patients with idiopathic generalized epilepsy scalp ripples are not useful.
To evaluate scalp ripples distribution in secondary bilateral synchrony as a tool to lateralize the epileptic focus and to differentiate focal from generalized epilepsy.
Seventeen EEG recordings with bilateral synchronous discharges of focal (focal group-FG: 10) and generalized (generalized group-GG: 7) epilepsy patients were selected for spikes and ripples marking; the spike-normalized ripple rate was calculated in each hemisphere (right/left – anterior/posterior) and a ripple-dominant hemisphere (the one with the highest rate) was identified. Concordance in FG between the ripple dominant hemisphere and the hemisphere of clinical lateralization was evaluated. The ripple-dominant/ripple-nondominant spike-normalized ripple rate ratio was studied to compare groups.
In FG the hemisphere of clinical lateralization and the ripple-dominant hemisphere were 100% concordant. In GG only 3/7 patients showed ripples (vs 10/10 FG), all with anterior dominance. No difference in hemisphere ripple dominance between groups was found.
Ripples in secondary bilateral synchrony help to lateralize the epileptic focus but do not help to differentiate between focal and generalized epilepsy. This is the first report of visually identified ripples in idiopathic generalized epilepsy.
Ripples confirm the clinical lateralization of the epileptic focus in secondary bilateral synchrony but cannot distinguish between focal and generalized epilepsy.
Abstract Morphological variations of hippocampal formation (MVHF) are observed in patients with epilepsy but also in asymptomatic individuals. The precise role of these findings in epilepsy is not ...yet fully understood. This study analyzes the hippocampal formation (HF) morphology of asymptomatic individuals (n = 30) and of patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) (n = 68), patients with malformations of cortical development (MCD) (n = 34), or patients with pure morphological variations of hippocampal formation (pure MVHF) (n = 12). Main clinical and electrophysiological data of patients with MVHF were also analyzed. Morphological variations of hippocampal formation are more frequently observed in patients with MCD than in patients with MTLE-HS or in asymptomatic individuals. Patients with pure morphological variations of hippocampal formation showed higher incidence of extratemporal seizure onset. Refractoriness seems to be more associated with other abnormalities, like HS or MCD, than with the HF variation itself. Thus, although morphological HF abnormalities might play a role in epileptogenicity, they seem to contribute less to refractoriness.
The aim of this retrospective study of a series of patients with mesial temporal lobe epilepsy (MTLE) and mesial temporal sclerosis (MTS) was to analyze the association of granule cell dispersion ...(GCD) with surgical prognosis, patterns of MTS and clinical data. Hippocampal specimens from 66 patients with MTLE and unilateral MTS and from 13 controls were studied. Quantitative neuropathological evaluation was performed on NeuN-stained hippocampal sections. Patients' clinical data, types of MTS and surgical outcome were reviewed. GCD occurred in 45.5% of cases and was not correlated with clinical variable. More severe neuronal loss was observed in patients with GCD. Except for MTS Type 2 - observed only in four no- GCD patients - groups did not differ with respect to the types of MTS. Surgical outcome was similar in both groups. In conclusion, GCD was associated with the degree of hippocampal cell loss, but was not a predictor of surgical outcome.
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