P.011 Not just for babies: positive rolandic sharp waves in adult post-hypoxic myoclonus

Abstract

Background: Post-hypoxic myoclonus is broadly divided into myoclonic status epilepticus (MSE) and Lance-Adams syndrome (LAS), where diagnosis depends on clinical and electroencephalographic (EEG) findings. Positive rolandic sharp waves (PRS) are a classic EEG finding in pre-term infants with white matter necrosis, but they are not known to be epileptogenic and have never been described in adults. Methods: We report a unique case of PRS correlated with myoclonic seizures in a post-hypoxic adult patient. Results: Shortly after cardiac arrest, a 21-year-old woman developed multifocal post-hypoxic myoclonus. Early development of myoclonus suggested MSE, but her EEG findings were atypical for MSE; initially, the only notable feature on EEG were subtle PRS. LAS did not fit the clinical picture or EEG findings. As myoclonus persisted over the following weeks, PRS evolved on EEG into positive rolandic predominant generalized polyspike-wave complexes that became definitively time-locked to each myoclonic jerk. PRS were diagnosed as epileptogenic and frequent myoclonic jerks were diagnosed as continuous myoclonic seizure. Myoclonus resolved to medication and mental status returned to baseline. Conclusions: We report for the first time that PRS can appear in adult patients and be epileptogenic, and produce a non-classical variant of post-hypoxic myoclonus that carries good prognosis.