Seizure Disorders Following Periodic Lateralized Epileptiform Discharges

Abstract

We reviewed 3,436 EEGs and found 24 patients with periodic lateralized epileptiform discharges (PLEDS). The etiology was unknown in 7, cerebrovascular occlusion in 7, tumor in 3, intracerebral hematoma in 2, and subdural hematoma, neonatal asphyxia, electrolyte imbalance, subarachnoid hemorrhage, and hypoglycemia in each of the remaining cases. We were successful in contacting 18 patients and/or their families for follow-up. Twenty of the 24 patients with PLEDS had seizures. Seven had focal motor alone, 10 had focal motor with secondary generalization, and 3 had generalized seizures without any observed focal features. Four patients had no seizures. Twelve patients had their first seizure at the time PLEDS were found. Fifteen adults and 3 infants were reevaluated. Only 1 adult was functionally independent. The 3 infants evidenced developmental delay. Six adults had seizures prior to observation of PLEDS, and 5 (83%) of them reported seizures after hospitalization. Nine of the 15 adults had their first seizure associated with PLEDS, 6 of whom (67%) also reported seizures after hospitalization. In 9 patients with serial EEGs during their hospitalization, PLEDS disappeared within 22 days. We concluded that most patients with PLEDS and concomitant seizures continue having seizures after hospitalization and need antiepileptic medication.

Neuronal Sodium Channels in Neurodegeneration and Neuroprotection

“…Most surprisingly, we found a highly significant association between the occurrence of PLEDs before NCS and prolonged NCS series. This is in agreement with previous findings of an association between severe seizure activity and PLEDs (34,37,38,53,57). For instance, Snodgrass et al (41) found that over 50% of all patients they catalogued with PLEDs exhibited electrographic status epilepticus.…”

“…The normally functioning brain is solely dependent upon induced, including traumatic brain injury, hemorrhage, or blood-delivered glucose as an energy source for the stroke [15,29,37]. Anticonvulsant therapy with agents production of adenosine-triphosphate (ATP).…”

Periodic electroencephalographic patterns: usefulness of definition and classification

“…The importance of EEG timing in the detection of epileptiform abnormalities has not been generally appreciated, despite the fact that at least one study has clearly demonstrated that the incidence of periodic EEG patterns increases when they are performed earlier in the course of the disease process 8,9 .…”

“…Among the clinical manifestations, seizures are the most important and striking feature associated with PLEDs, occurring with a frequency from 58 to 100% 2,[8][9][10][11] . This wide range probably reflects the heterogeneity of patient selection and study design.…”

“…This wide range probably reflects the heterogeneity of patient selection and study design. Focal motor seizures are usually seen in this clinical setting, often presenting as status epilepticus (epilepsia partialis continua) or as repetitive focal motor seizures 2,[8][9][10][11] .…”