Introduction: While seizures are uncommon but reported in primary intraventricular hemorrhage (IVH), little evidence is available on the prevalence of hyperexcitable patterns on long term EEG monitoring.
Methods: We sought to determine the prevalence of hyperexcitable patterns and seizures in patients with primary IVH who were extracted from a cohort consisting of patients with spontaneous intracerebral hemorrhage (sICH) who underwent continuous electroencephalogram (cEEG) monitoring between January 2013 and December 2016 at Yale-New Haven Hospital. Indications for cEEG monitoring included fluctuation of or depressed mental status, abnormal movements and a limited clinical exam. We recorded demographics, radiologic hydrocephalus, duration of EEG recording and EEG findings. Hyperexcitable patterns comprised generalized, bilateral independent or lateralized periodic discharges (PDs), lateralized rhythmic delta activity (RDA), brief potentially ictal rhythmic discharges (B(I)RDs), and spike-and-wave discharges (SW).
Results: Of 196 adults with sICH who had cEEG performed, 13 patients (54% female) had primary IVH. Hydrocephalus was present in 9 patients (69%). Patients were monitored for a mean duration of 22.4 (± 14.7) hours. 9 patients had hyperexcitable patterns and/or electrographic seizures (70%): Electrographic seizures and co-existent hyperexcitable patterns were captured in 2 of 13 patients (16%) and hyperexcitable patterns without seizures in 7 of 13 patients (54%). Hyperexcitable patterns included periodic discharges (PDs) (4) (generalized, lateralized and bilateral independent, with and without rhythmicity), rhythmic delta activity (RDA) (5) (both lateralized and generalized, with and without sharps), brief potentially ictal rhythmic discharges(B(I)RDs) (1) and spike-and-wave discharges (SW) (1). There was no significant difference between patients with and without hydrocephalus and hyperexcitability or electrographic seizures (p= 0.76).
Conclusion: Both electrographic seizures and/or patterns of hyperexcitability on EEG are common in our cohort of primary IVH patients. The exclusion or detection of non-convulsive seizures offers an opportunity for therapeutic intervention.