Abstracts

Rationale: To retrospectively evaluate the frequency of occurrence, the relevant clinical features, and the EEG evolution of combinations of generalized spike wave discharges (GSWD) and benign focal discharges of childhood (BFDC) in patients at the University of Rochester's Strong Epilepsy Center (SEC) between 2000 and 2009. Methods: The archival EEG database and URMC's Allscripts database were the data sources and reviewed for this study. Inclusion criteria: 1) Males and females 1-20 years old, inclusive, who have been identified as having benign focal discharges and generalized spike discharges with normal EEG background 2) Normal neurological status 3) Normal brain imaging Results: A total of 489 cases were identified. We eliminated 388 patients with benign focal discharges of childhood with centro-temporal spikes (BCECT) and 54 with benign focal discharges of childhood with occipital spike/paroxysmal (BEOP) alone. The remaining 47 patients had combined diagnoses. Age range was 2-18.5 years, average age was 8.2 years. Of these, 39 (83%) had BCECT+GSWD and 8 (17%) had BEOP+GSWD. The average age of seizure onset was 6.1 years. There were generalized seizure in 34 patients (72.3%) which included 28 BCECT+GSWD and 6 BEOP+GSW patients. There were focal seizures in 8 patients (17%) 6 of which had BCECT+GSWD and 2 had BEOP+GSWD. Three patients (6.4%) with BCECT+GSWD had both generalized and focal seizures while the 2 BCECT+GSWD patients (4.3%) had no seizures. A photoparoxysmal response was present in 8 (17.2%), with 1 BEOP+GSWD and 7 BCECT+GSWD patients. There was a positive family history of seizures in 17 (36.2%), negative in 25 (53.2%) and unknown in 5 (10.6%). Imaging was done in 27.7%. Normalization of the EEG during the 10 year period was 25.5% and average age to normalization 11.8 years. 10.6% resolved to only GSWD and 17 % to only BCECT or BEOP. Age of first EEG with combined discharges was 8 for BCECT+GSWD and 11.6 for EOP+GSWD. On first diagnostic study, 4.26% had a normal first EEG, 12.8% had BCECT and 8.5% had GSWD. The majority of first EEGs (74.5%) had combined discharges Conclusions: We found the frequency of GSWD was higher in the BCECT group than in those with BEOP. However, the number of patients with BEOP was significantly smaller than that with BCECT, therefore the occurrence of BEOP in combination with GSWD was notably higher than BCECT combined with GSWD. The onset of BCECT, BEOP or GSWD can be first, followed by the second type, however, we often found a combination in the majority of first EEGs (74.47%). Interestingly, the age of appearance of BEOP with GSWD was older than BCECT with GSWD. Clinical manifestation was categorized as generalized seizure more than focal seizure, in both groups. The few patients who had both seizure types were only in the BCECT+GSWD group, as were the few who had no detectable seizures. During the 10 years covered by the data, normalization of EEG occurred 25.53% and revealed changes in epileptiform discharges in both directions, i.e., combinations resolved to a single discharge type.