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Objective: This study aims to assess the prognostic value of acute postoperative seizures (APOS) in patients surgically treated for drug-resistant extra-temporal lobe (ET) epilepsy., Methods: We studied 77 consecutive patients with ET epilepsy who underwent epilepsy surgery and were followed up for at least 2 years (mean duration of follow-up 6.2 years, range 2-14). Medical charts were reviewed to identify APOS, defined as ictal events with the exception of auras occurring within the first 7 days after surgery. Seizure outcome was determined at annual intervals. Patients who were in Engel Class I at the last contact were classified as having a favourable outcome., Results: Seizure outcome was favourable in 47 patients (61%). The occurrence of APOS and incompleteness of resection were found to be independently associated with unfavourable outcome in a multiple regression model including all preoperative factors identified as outcome predictors in univariate analysis. Duration of illness was the only independent preoperative predictor of APOS., Conclusions: Our study suggests that APOS may predict long-term outcome in patients undergoing resective surgery for ET epilepsy. Given some study limitations, our findings should be regarded as preliminary and need confirmation from future larger, prospective, multicentre studies., Significance: Caution may be required in the clinical management of patients experiencing APOS., (Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: To assess the prognostic value of postoperative EEG in patients surgically treated for drug-resistant extra-temporal lobe (ET) epilepsy., Methods: We studied 63 consecutive patients with ET epilepsy who underwent epilepsy surgery and were followed up for at least 2 years (mean duration of follow-up 6.2 ± 2.3 years, range 2-12). Follow-up evaluations were performed 2, 12, and 24 months after surgery, and included standard EEG (at 2 months) and long-term video-EEG monitoring during both wakefulness and sleep (at 12 and 24 months). Seizure outcome was determined at each follow-up evaluation, and then at yearly intervals. Patients who were in Engel Class I at the last contact were classified as having a good outcome., Results: Seizure outcome was good in 39 patients (62%). The presence of interictal epileptiform discharges (IED) in postoperative EEG at each time point was found to be associated with poor outcome. The strength of this association was greater for awake plus sleep recording as compared with awake recording alone. In a multiple regression model including all pre- and post-operative factors identified as predictors of outcome in univariate analysis, the presence of early (2 months after surgery) EEG epileptiform abnormalities was found to be independently associated with poor seizure outcome., Conclusions: Postoperative IED may predict long-term outcome in patients undergoing resective surgery for ET epilepsy., Significance: The increase in risk of unfavourable outcome associated with EEG epileptiform abnormalities detected as early as two months after surgery may have substantial practical importance. Serial postoperative EEGs including sleep recording may add further predictive power and help making decision about antiepileptic drug discontinuation., (Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: To assess the prognostic value of scalp electroencephalogram (EEG) after epilepsy surgery, we investigated whether postoperative EEG abnormalities (interictal epileptiform discharges, IED; interictal slow activity, ISA) were associated with seizure outcome and other patient characteristics after resective surgery in patients with temporal lobe epilepsy (TLE)., Methods: Sixty-two patients with medically refractory TLE who underwent surgery were studied. Patients were categorized according to etiology (mesiotemporal sclerosis vs. tumors/cortical dysplasias); extent of surgical resection (extensive vs. limited); and amount of preoperative IED on wake EEG (oligospikers, <1 IED/h, vs. spikers). Patients were also classified as seizure-free (SF) or having persistent seizures/auras (not-SF) during follow up visits 1 month and 1 year after surgery. Preoperative 60-min interictal EEGs were evaluated for IED and ISA, and compared to postoperative wake EEGs., Results: Seizures/auras persisted in 16/62 (25.8%) patients at 1 month and in 8/62 (12.9%) at 1 year follow up. ISA was not significantly related to outcome. Of 42 patients with EEG negative for IED at 1 month, 4 were not-SF; at 1 year, one of 44 such patients was not-SF. IED was significantly associated with seizure/aura persistence in patients categorized as mesiotemporal sclerosis and with extensive surgery. Oligospikers and spikers on preoperative EEG showed no differences in the postoperative seizure outcome, excellent in both cases; moreover, the presence of postoperative IEDs indicated auras/seizures persistence apart from the preoperative EEG spike frequency., Conclusions: Our study showed that the presence of IED of postoperatve EEG strongly indicates seizure/aura persistence. Therefore, serial EEGs should be included in postoperative follow up schedules as a crucial tool in evaluating seizure outcome.

Objective: Heart rate (HR) changes, mainly tachycardia, are often observed during seizures originating from the temporal lobe. The aim of this study was to analyze the role of ictal HR changes in localizing both mesial and lateral temporal lobe epilepsy (TLE) in a group of 68 patients. The influence of the gender and the side of epilepsy on HR modulation was also evaluated., Methods: Ictal HR was recorded during prolonged Video-EEG monitoring performed in 68 patients affected by drug-resistant TLE during a non-invasive pre-surgical protocol. According to the electro-clinical correlation, obtained by video-EEG monitoring, one hundred-thirteen seizures (n=113) and one hundred-forty-four auras (n=144) were identified and included in the study. Furthermore, the electro-clinical correlation allowed the classification of all the epileptic events (seizures and auras) as having mesial or lateral origin, based on the temporal lobe seizure onset zone. Ictal HR was calculated with respect to the R-R waves, and assessed from 15 sec (s) before (T(- 15)) to 15 s after (T(+15)) the time of EEG seizure onset (T(0))., Results: We observed a high incidence (92%) of ictal HR increase in TLE seizures. When the ictal EEG indicated a seizure onset from the mesial temporal structures, the onset of ictal HR increase preceded by about 5 s the EEG ictal onset (SD+/-18.4), whereas the onset of HR increase coincided with the onset of EEG discharges (SD+/-14.8) when the ictal EEG indicated the onset of seizures from the lateral temporal structures. No significant differences were found between male and female patients; and between right and left TLE., Conclusions: Our findings show that ictal HR increase, preceding the onset of the EEG discharge, is associated with ictal EEG seizure pattern defining temporal lobe seizures originating from the mesial temporal lobe structures; this association suggests that the HR changes may be coupled to the functional impairment of neural circuits involved in sympathetic cardiovascular regulation, in the mesial temporal lobe structures. Further studies investigating the relationship between intracranial EEG monitoring and ECG recording are worthwhile, to confirm our results and to give further indications on the pathogenesis of ictal HR abnormalities.

Objective: Temporal intermittent rhythmic delta activity (TIRDA) is an EEG pattern characterized by sinusoidal trains of activity, ranging from 1 to 3.5 Hz, and well localized over the temporal regions. It is considered to be an indicator of temporal lobe epilepsy (TLE), but full agreement between different authors has still not been reached. The aim of this study was therefore to assess the role of TIRDA in localizing the epileptogenic zone, which was estimated using anatomo-electro-clinical correlations obtained from non-invasive pre-surgical investigations, in a large group of patients affected by drug-resistant partial epilepsy., Methods: The occurrence of TIRDA was investigated using a prolonged Video-EEG recording of 129 patients affected by drug-resistant partial epilepsy that underwent a non-invasive pre-surgical protocol. Patients were divided into 3 groups: TLE only, extratemporal epilepsy, and multilobar epilepsy including temporal lobe. According to the epileptogenic zone identified using anatomo-clinical-radiological correlations, 3 different subgroups of TLE were identified: mesial, lateral, and mesio-lateral. Statistical analysis was performed in order to evaluate the relationship between TIRDA and the epileptogenic zone, and neuroradiological, neuropathological, EEG interictal and ictal findings., Results: The pattern of TIRDA was observed in 52 out of the 129 (40.3%) patients studied. Significant correlations were found between TIRDA and: (i) mesial and mesio-lateral TLE; (ii) mesial temporal sclerosis; (iii) interictal epileptiform discharge localized over the anterior temporal regions; and (iv) 5-9 Hz temporal ictal discharge., Conclusions: Our research shows that TIRDA plays a role in localizing the epileptogenic zone, suggesting that this pattern might be considered as an EEG marker of an epileptogenesis that involves the mesial structures of the temporal lobe. However, further studies investigating the relationship between intracranial EEG monitoring and simultaneous scalp EEG recording are needed in order to confirm our findings and improve our understanding of the significance of TIRDA.