One-Stage, Limited-Resection Epilepsy Surgery for Bottom-of-Sulcus Dysplasia.

OBJECTIVE: To determine whether 1-stage, limited corticectomy controls seizures in patients with MRI-positive, bottom-of-sulcus dysplasia (BOSD). METHODS: We reviewed clinical, neuroimaging, electrocorticography (ECoG), operative, and histopathology findings in consecutively operated patients with drug-resistant focal epilepsy and MRI-positive BOSD, all of whom underwent corticectomy guided by MRI and ECoG. RESULTS: Thirty-eight patients with a median age at surgery of 10.2 (interquartile range [IQR] 6.0-14.1) years were included. BOSDs involved eloquent cortex in 15 patients. Eighty-seven percent of patients had rhythmic spiking on preresection ECoG. Rhythmic spiking was present in 22 of 24 patients studied with combined depth and surface electrodes, being limited to the dysplastic sulcus in 7 and involving the dysplastic sulcus and gyral crown in 15. Sixty-eight percent of resections were limited to the dysplastic sulcus, leaving the gyral crown. Histopathology was focal cortical dysplasia (FCD) type IIb in 29 patients and FCDIIa in 9. Dysmorphic neurons were present in the bottom of the sulcus but not the top or the gyral crown in 17 of 22 patients. Six (16%) patients required reoperation for postoperative seizures and residual dysplasia; reoperation was not correlated with ECoG, neuroimaging, or histologic abnormalities in the gyral crown. At a median 6.3 (IQR 4.8-9.9) years of follow-up, 33 (87%) patients are seizure-free, 31 off antiseizure medication. CONCLUSION: BOSD can be safely and effectively resected with MRI and ECoG guidance, corticectomy potentially being limited to the dysplastic sulcus, without need for intracranial EEG monitoring and functional mapping. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that 1-stage, limited corticectomy for BOSD is safe and effective for control of seizures.

Clinical seizure manifestations in the absence of synaptic connections.

We report a child with a history of temporal-parietal-occipital disconnection for epilepsy secondary to posterior quadrantic dysplasia who developed recurrent and prolonged bouts of distress and autonomic disturbance associated with EEG and PET evidence of status epilepticus confined to his disconnected cortex. These bouts were refractory to antiseizure medications but resolved following resection of the disconnected cortex. In the absence of synaptic connections, we hypothesise that his seizure-related symptoms were mediated either by neurochemical transmission in preserved vascular and lymphatic channels or by ephaptic transmission to trigeminal nerve fibres in overlying dura, producing symptoms akin to migraine. The case highlights potential means by which seizures may manifest clinically, without synaptic connections, and adds to the differential for symptoms post-disconnection surgery.

Focal cortical hypermetabolism in atypical benign rolandic epilepsy.

OBJECTIVE: Atypical benign rolandic epilepsy (BRE) is an underrecognized and poorly understood manifestation of a common epileptic syndrome. Most consider it a focal epileptic encephalopathy in which frequent, interictal, centrotemporal spikes lead to negative motor seizures and interfere with motor and sometimes speech and cognitive abilities. We observed focal cortical hypermetabolism on PET in three children with atypical BRE and investigated the spatial and temporal relationship with their centrotemporal spikes. METHODS: EEG, MRI and PET were performed clinically in three children with atypical BRE. The frequency and source localization of centrotemporal spikes was determined and compared with the location of maximal metabolic activity on PET. RESULTS: Cortical hypermetabolism on thresholded PET t-maps and current density reconstructions of centrotemporal spikes overlapped in each child, in the central sulcus region, the distances between the "centers of maxima" being 2 cm or less. Hypermetabolism was not due to recent seizures or frequent centrotemporal spikes at the time of FDG uptake. SIGNIFICANCE: The findings suggest that localized, increased cortical activity, in the region of the EEG focus, underlies the negative clinical manifestations of atypical BRE. Similar findings are reported in the broader group of epileptic encephalopathies associated with electrical status epilepticus in sleep.

Intrinsic epileptogenicity of cortical tubers revealed by intracranial EEG monitoring.

OBJECTIVE: We sought to identify intracranial EEG patterns characteristic of epileptogenic tubers and to understand the contribution of perituberal cortex. METHODS: Twenty-three intracranial EEG monitoring studies were reviewed from 17 children aged 1.3-7.7 years with tuberous sclerosis complex and intractable multifocal epilepsy, 14 with a history of epileptic spasms. Interictal epileptiform discharges and ictal rhythms for 60 electroclinically distinct seizures (EDS) were analyzed in relation to 162 sampled tubers. RESULTS: Localized, tuber-related, ictal rhythms were seen in 49/60 EDS, most commonly as low-voltage fast activity recruiting to rhythmic spiking, then diffuse slowing or bursts of ripple range activity. Ictal onset in localized EDS involved only tubers in 57% and tubers with perituberal cortex in 31%. Ictal fast ripples (FR) noted at seizure onset in 15/38 localized EDS were confined to tubers in 73% and involved tuber with perituberal cortex in 27%. Intraictal activation occurred during seizure propagation in 19 localized EDS, being to tubers in 63% and to tubers with perituberal cortex in 37%; 63% of activated tubers generated independent EDS. Trains of periodic sharp waves on an attenuated background were seen interictally at 36/162 tubers, with 67% of those tubers generating EDS (p = 0.0001). Interictal FR, when present, involved tubers more commonly than perituberal cortex but were not associated with EDS. CONCLUSION: The study demonstrates interictal and ictal intracranial EEG findings characteristic of epileptogenic tubers, suggests that tubers play a greater role in seizure genesis than perituberal cortex, and suggests tuberectomy may be a sufficient surgical approach in a number of patients.

Preventing hospital-associated infection: MRSA.

By understanding the preventive strategies associated with reducing HA-MRSA transmission, the medical-surgical nurse can impact mortality rates and health care costs. He or she should model and enforce adherence to prevention strategies, such as hand hygiene, contact isolation, and other evidence-based strategies.

Long-term follow-up of febrile infection-related epilepsy syndrome.

PURPOSE: Febrile infection-related epilepsy syndrome (FIRES) is an increasingly recognized epileptic syndrome that presents with multifocal refractory status epilepticus in previously normal children and evolves into a chronic, refractory, focal epilepsy with associated cognitive and behavioral difficulties. Herein we describe the features of the chronic epilepsy and critically review evidence for the etiology of this syndrome. METHODS: Seven patients with FIRES were studied. The duration of follow-up in six survivors was 5-17 years. Clinical, electroencephalography (EEG), neuroimaging, and other investigative findings during the acute and chronic phases were reviewed. KEY FINDINGS: These previously normal children presented with a febrile illness and status epilepticus that was refractory to antiepileptic medications in all children, to immunotherapies (including immunoglobulin, corticosteroids, plasma exchange, and rituximab) in four, and to acute vagus nerve stimulation in one. Markers of cerebral inflammation were few and response to antiepileptic and immunomodulatory therapies was poor. Evolution to chronic epilepsy occurred without a silent period. Seizure characteristics in the chronic phase were strikingly stereotyped and similar to the acute phase, with head and eye version, unilateral facial jerking, asymmetric tonic posturing, and unilateral limb jerking in all patients. Electrographic ictal onset was lateralized in all recorded seizures, unilateral in one patient, and independent bilateral in three. Seizures were refractory to multiple antiepileptic medications in all patients and partly responsive to chronic vagus nerve stimulation in two patients. Moderate to severe intellectual impairment was noted in four patients, and borderline intellectual abilities were noted in two. Magnetic resonance imaging (MRI) in the chronic phase was normal in three patients and showed mild diffuse cortical atrophy and/or mild hippocampal atrophy or sclerosis in three. SIGNIFICANCE: The similar perirolandic and perisylvian features of acute and chronic seizures, the lack of a silent period, the absence of evidence of cerebral inflammation, and the poor response to immunotherapies suggest FIRES is best conceptualized as a chronic epilepsy with explosive onset, not a remote-symptomatic epilepsy with an acute inflammatory antecedent.

Temporoparietooccipital disconnection in children with intractable epilepsy.

OBJECT: Temporoparietooccipital (TPO) disconnection is described mainly in children with diffuse posterior quadrant lesions and concordant electroencephalography (EEG) findings. The authors report on 16 children who underwent TPO surgery, including 4 with no definite epileptogenic lesion and 8 with generalized electroclinical manifestations. METHODS: The authors conducted a retrospective review of clinical, neuropsychological, EEG, imaging, and histopathological data in 16 children with intractable epilepsy who underwent TPO disconnection and/or resection at their center between December 1998 and March 2010. RESULTS: Seizure onset occurred between the ages of 1 and 24 months, and TPO surgery was performed between the ages of 0.2 and 17 years. All children had refractory seizures, including epileptic spasms in 10 and tonic seizures in 7, and all had developmental delay. Twelve children had epileptogenic lesions on MR imaging, including 6 with posterior quadrant dysplasia. Four children had only subtle white matter signal change or unusual sulcation on MR imaging, associated with subtle but concordant EEG and functional imaging abnormalities. After a mean follow-up of 52 months (range 12-114 months), 9 children (56%) are seizure-free and 5 (31%) experienced seizure reduction of greater than 50%. Focal or regional background slowing on EEG was correlated with favorable seizure outcome. Five children showed developmental progress and 3 had acceleration in development following surgery. None of the children developed new motor deficits postoperatively. CONCLUSIONS: Temporoparietooccipital disconnection is an effective, motor-sparing epilepsy surgery procedure for selected children with refractory focal or generalized seizures with localization to the posterior quadrant on 1 side, with or without a discrete lesion on MR imaging.