Bernardo Boleaga

Subacute electrical stimulation of the hippocampus blocks intractable temporal lobe seizures and paroxysmal EEG activities.

Summary: Purpose: To investigate the clinical, electroen‐cephalographic (EEG), and histopathologic effects of subacute electrical stimulation of the hippocampal formation or gyms (SAHCS) on 10 patients with intractable temporal lobe seizures.

Neuromodulation of the Centromedian Thalamic Nuclei in the Treatment of Generalized Seizures and the Improvement of the Quality of Life in Patients with Lennox–Gastaut Syndrome

Summary:  Purpose: Our aim was to evaluate the efficacy of ESCM (electrical stimulation of the centromedian thalamic nucleus) in treatment of generalized seizures of the Lennox–Gastaut syndrome (LGS) and improvement of patient disability.

Absolute and Relative Predictor Values of Some Non-Invasive and Invasive Studies for the Outcome of Anterior Temporal Lobectomy

BACKGROUND There is controversy in the literature regarding the strategy used to obtain better outcomes after performing an anterior temporal lobectomy (ATL). Some investigators prefer to reduce the risks and costs of the predictor studies despite the fact that the number of patients cured after ATL (no seizures with no medication) is relatively small. Other investigators prefer to attempt a total cure in all patients by using all available predictor studies regardless of risks and costs. The latter strategy was the aim of the present work. METHODS The absolute (%) and relative (ratio differences) predictor values of non-invasive and invasive studies for the outcome 24 months post-ATL were determined on 22 patients suffering from intractable non-lesional temporal lobe epilepsy. RESULTS Under these conditions, 11 (50%) patients had excellent outcomes (seizure-free, no medication), 8 ( 36%), good outcomes (only auras with medication), and 3 (13.6%), poor ou tcomes (1 with >70%-seizure reduction and two no changes in seizure frequency). Predictors of excellent (vs. poor outcome) include the following: complex partial seizures (CXP) alone or associated with secondary generalized tonic-clonic seizures; ictal motionless stare and postictal amnesia; abnormal bitemporal spikes (prominent ipsilateral to ATL) and secondary bilateral synchrony EEG activities; focal hippocampal ictal EEG activities, and the presence of focal anterior temporal delta EEG activity 3 months after ATL. Predictors of poor (vs. excellent) outcomes include the following: CXP associated with other generalized seizure types; CTS, MRI, and EEG extratemporal abnormalities, and generalized basotemporal ictal EEG activities and the presence of seizures and focal anterior temporal spikes 3 months after ATL. CONCLUSIONS The present study corroborates that no single predictive study (including non-invasive MRI and invasive ictal EEG activity) is predictive of the success or failure of ATL. Rather, a concordant combination of non-invasive and invasive studies is more likely to be predictive of a high probability of success. The high efficiency of ATL (86% of patients seizure-free) was accomplished by using all available predictor studies.

Motor Cortex Stimulation in the Treatment of Deafferentation Pain. I. Localization of the Motor Cortex1

MRI and electrophysiological techniques to localize the primary motor cortex (MC) were performed on patients considered for MC stimulation for the treatment of deafferentation pain. The representation and trajectory of the rolandic fissure (RF) were accurately localized by external cranial landmarks and radiopaque fiducials superimposed on oblique MRI sections. In addition, the scalp distribution of the corticocortical responses elicited by acute epidural stimulation [motor cortex (MC) in frontal and sensory cortex (SC) in parietal scalp regions], and analgesic responses at the topographical representation of the painful periphery elicited by subacute epidural stimulation were found to be simple and reliable procedures to localize MC, SC and RF.

Electroencephalographic and Magnetic Resonance Correlations in Children with Intractable Seizures of Lennox-Gastaut Syndrome and Epilepsia Partialis Continua

Summary: A study was performed of EEG‐magnetic resonance imaging (MRI) abnormalities in 7 Lennox‐Gastaut syndrome (LGS) children and 3 epilepsia partialis continua (EPC) children with intractable generalized and partial motor seizures, respectively. In 4 children with LGS and 3 children with EPC, depth electrodes were implanted in the centromedian thalamic nuclei (CM) for seizure control. In all children with LGS, hyperdense, T2‐weighted MRI signals were observed at the mesencephalic level of the brainstem, whereas none of the 3 children with EPC had this finding. Patients with idiopathic LGS without cerebral hemisphere MRI abnormalities showed generalized bilateral and symmetrical spike‐wave EEG activity. Patients with symptomatic LGS with unilateral hemispheric MRI abnormalities demonstrated asymmetrical EEG activity with higher amplitude spike‐and‐wave over the normal hemisphere. Patients with EPC with unilateral hemispheric lesions had lateralized higher amplitude spike‐wave over the damaged hemisphere. These data suggest that abnormal mesencephalic MRIs are a sign of bad prognosis in patients with LGS but not with EPC. Maximal amplitude paroxysmal EEG activities may indicate the abnormal hemisphere in patients with EPC or the normal hemisphere in those with LGS.