Abstracts

The gold standard of diagnosis of nonconvulsive status epilepticus (NCSE) is EEG. Studies on NCSE and the literature often imply that the EEG diagnosis of NCSE is straightforward, but NCSE has several different EEG presentations. In particular, generalized periodic patterns or [quot]GPEDS[quot] can be seen in NCSE but also in non-epileptic encephalopathies such as anoxic or metabolic disturbances. This study sought to evaluate whether GPEDS patterns are usually read as suggestive of status epilepticus., We sent a single 10-second epoch of EEG by e-mail, and we reviewed the interpretations of the readers. We were specifically interested whether the possiblity of NCSE would be raised based on this EEG pattern. Two groups of reviewers were surveyed: 1) Epileptologists or electroencephalographers (EEGers) at tertiary epilepsy centers or EEG laboratories (N=14) and 2) General practicing board-certified neurologists (N=12). The sample is shown in the figure. The history was limited and read as follows: 60 year-old male found down and admitted [quot]altered mental status[quot] or [quot]coma.[quot] History was intentionally limited, as we were interested in the impression of the EEG sample prior to integrating it with the history., In the epileptologists or EEGers sample, 100% mentioned NCSE (along with metabolic and other encephalopathies).
In the general neurologist sample, 42% mentioned NCSE while 58% did not and limited the interpretation to severe diffuse encephalopathy., There was a significant difference between epileptologists/EEGers and general neurologists regarding whether GPEDS should suggest a diagnosis of NCSE.[figure1],