To the Editor I read with interest the article by Yoo et al1 on brief potentially ictal rhythmic discharges visualized in continuous electroencephalography recordings of critically ill patients. Periodic patterns, such as atypical triphasic waves, and lateralized epileptiform discharges are not so uncommonly seen in the electroencephalograms of critically ill patients. Current understanding is that they lie on the continuum of interictal-ictal and most experienced electroencephalographers choose not to treat the electroencephalography unless there is some added rhythmicity to these discharges or accompanying subtle clinical correlate such as facial twitching or myoclonic jerks. Brief potentially ictal rhythmic discharges seem to lie in the same category too. Their presence in a record certainly indicates the potential for epileptogenicity but their mere presence should not warrant anticonvulsant treatment. On the other hand, if brief potentially ictal rhythmic discharges coexist with electrographic or electroclinical seizures in the same record, aggressive anticonvulsant treatment is justified.
Sethi NK. Brief Rhythmic Discharges in Electroencephalography on an Interictal to Ictal Continuum. JAMA Neurol. 2014;71(9):1193. doi:10.1001/jamaneurol.2014.1862