Table 2.
American Clinical Neurophysiology Society Research Criteria for Nonconvulsive Seizures [and, if > 30 min, Nonconvulsive Status Epilepticus]
| (1) | Repetitive generalized or focal spikes, poly-spikes, sharp waves, spike-and-wave or sharp-and-slow wave complexes, or other rhythmic waveforms at > 2.5/s, lasting longer than 10 s, or |
| (2) | The same waveforms as above, with discharges < 2.5/s, but with ….. |
| (a) | Clear clinical ictal phenomena, such as facial twitching, nystagmus, or limb myoclonus. |
| (b) | An unequivocal evolution of the rhythmic pattern, including increase or decrease in frequency (by > 1 Hz), change in discharge morphology, or in location (gradual spread of rhythmic activity into or out of a region involving at least 2 electrodes). Changes in discharge amplitude or “sharpness” alone are not sufficient, or |
| (c) | Rhythmic delta waves at > 1/s, with the additional criterion of unequivocal clinical improvement, or improvement on EEG [such as resolution of epileptiform discharges and reappearance of previously-absent normal background rhythms and reactivity] or both, following quickly after acute administration of rapid- acting ASDs, typically BZDs. (Resolution of discharges leaving a slow background alone, without clinical improvement, would not suffice.) |