T20. EEG characteristics affecting response to therapy in selected patients with infantile spasms and hypsarrhythmia

Abstract

Introduction The presence of hypsarrhythmia and occurrence of infantile spasms constitute a severe form of epilepsy in infants that warrants early identification and treatment. The aim of this study is to evaluate the EEG patterns in such patients that may predict a more favorable response to therapy.

Methods The charts and EEG recordings of 4 patients with infantile spasms and hypsarrhythmia who were seen in our academic center at the Lebanese American University Medical Center between January 1, 2017 and October 20, 2017 were reviewed. EEG characteristics collected included focality of the hypsarrhythmia (generalized, multifocal, bihemispheric), prevalence of the hypsarrhythmia and presence of sleep architecture as well as documentation of the therapies attempted and the response to these therapies.

Results Four patients with new onset infantile spasms with associated hypsarrythmia were studied. In only one case, prompt response to starting VGB was seen whereas all other cases required the use of high dose prednisone after a trial of VGB failed to achieve clinical remission. In all 4 cases, spasm cessation was achieved within 2 months of clinical spasm onset. The most notable EEG characteristic of the case that responded promptly to VGB was focality of the hypsarrhythmia. In 2 of the 3 cases that required high dose steroids, the initial hysarrythmia pattern was seen predominantly during sleep and precluded presence of any sleep architecture.

Conclusion The presence of focal hypsarrhythmia and the persistent presence of normal sleep architecture predicted a more favorable response to therapy in patients with infantile spasms.