Table 2.

Continuous EEG features

Overall prevalence of EEG patterns	N (% of 143)
Electrographic seizures	24(16.8%)
Lateralized periodic discharges (LPDs)	33 (23.1%)
Bilateral independent periodic discharges (BIPDs)	6 (4.2%)
Generalized periodic discharges (GPDs)	17 (11.9%)
Lateralized rhythmic delta activity (LRDA)	23 (16.1%)
Generalized rhythmic delta activity (GRDA)	34(23.8%)
Sporadic discharges	81(56.7%)
Isolated vs. Multiple overlapping patterns	N (% of 67)
Isolated electrographic seizures	4 (6.0%)
Isolated LPDs	10 (14.9%)
Isolated BIPDs	2 (3.0%)
Isolated GPDs	9 (13.4%)
Isolated LRDA	3 (4.5%)
Isolated GRDA	13 (19.4%)
Multiple patterns	39 (58.2%)
Maximum daily burden a	N (% of 67)
Rare (<1%)	4 (6.0%)
Occasional (1–9%)	7 (10.4%)
Frequent (10–49%)	16 (23.9%)
Abundant (50–89%)	27 (40.3%)
Continuous (>90%)	13 (19.4%)
Maximum frequency	N (% of 67)
≥ 1.5 Hz	49 (73.1%)
< 1.5 Hz	18 (26.9%)

^a)18–24 hour epoch with the maximum daily burden of EAs.

EAs: epileptiform abnormalities