WS is a rare epileptiform
encephalopathy, and a high index of suspicion is needed for identification.
In 2013, a prospective study[sup] in China including 162 cases with MCHI demonstrated that a lack of EEG reaction, regional attenuation without delta mode, burst suppression pattern, alpha/theta coma pattern, and epileptiform
discharges (no burst suppression) and an extensive mode of inhibition also indicate poor prognosis (Evidence Class Ib).
Periodic lateralized epileptiform
discharge (PLED): Lateralized means that unilateral and bilateral synchronous but asymmetric; includes focal, regional, and hemispheric patterns.
1) Preoperative depression, interictal psychosis, and epileptiform
discharges contralateral to the epileptogenic zone are the most frequent predictors of postoperative psychosis.
disconnection procedures (disconnecting the epileptiform
cortex from the rest of the brain by sectioning white matter tracts)
reported that the epileptiform
discharge propagated from the seizure onset zone to different cortical areas with different time delays .
Since sleep is as a rule electroencephalographically expressed as synchronization, the electrophysiological pattern probably favors epileptogenesis (BAZIL; WALCZACK, 1997), while desynchronized sleep suppresses generalized epileptiform
discharges and shows variable effects on focal discharges (NEGRILLO, 2013).
The risk of recurrence was doubled for patients who had a predisposing clinical factor: a prior brain lesion, abnormal structural imaging of the brain, an EEG with epileptiform
waves, or a nocturnal seizure.
They discuss its cellular basis; cortical generators and EEG voltage fields; engineering principles; recording techniques; normal adult and pediatric EEG; generalized encephalopathy; EEG in cerebrovascular disease, neoplasms, and infections; progressive childhood encephalopathy; pediatric epilepsy syndromes; EEG in adult epilepsy; EEG voltage topography and dipole source modeling of epileptiform
potentials; subdural electrode corticography; intracerebral depth electrode electroencephalography; evoked potentials (EP); and sleep disorders.
Electrodes positioned on the surface of the head (scalp EEG) or inside the brain (intracranial EEG) can be used to study the various epilepsy hallmarks, such as seizures and interictal (between seizures) epileptiform
discharges (spikes or spike-and-wave complexes).
Electroencephalography in 30 cases demonstrated findings consistent with generalized encephalopathy in 22 (73%); seven demonstrated epileptiform
Interictal electroencephalography (EEG) in JME shows interictal epileptiform
discharges such as generalized spikes, polyspikes, bilateral-synchronous 4-6/s spike-wave complexes, or combinations of these [6, 7].
Serial electroencephalograms (EEGs) were interpreted as having general alterations of moderate severity: the presence of generalized delta and theta waves, mainly in the right hemisphere, typical epileptiform
waves, indicative of seizure activity, originating in the right fronto-temporal lobe, all in all, an increased cerebral excitability.
The device includes an implantable generator that is placed in the skull and deep brain stimulation leads that detect epileptiform
activity if placed near the seizure focus.
1,2) The patient in this case report had evidence of epileptiform
activity probably due to focal ischemia.