Abstracts

Rationale: To present a case of paroxysmal stereotypic episodes attributed to plateau waves, which may be mistaken to be seizures. Although this was previously documented in setting of meningeal pathology and mass lesions, this case is unique by presenting this phenomenon in the setting of ventriculoperitoneal-shunt malfunction.

Methods: 20-year-old woman with Chiari malformation, spina-bifida and ventriculoperitoneal-shunt, presenting with abrupt onset of daily paroxysmal spells concerning for seizure activity, resulting in initiation of anti-seizure medication without amelioration.

Results: During the stereotypic episodes she suffered from paroxysmal headache, drowsiness, poor responsiveness and relative bradycardia. EEG confirmed relative bradycardia and rapid build-up of generalized rhythmic delta activity without ictal features. Intracranial Pressure (ICP) modulating maneuvers and lack of epileptiform activity on EEG, or localizing ictal semiology, prompted obtaining shunt imaging and brain MRI. The patient was subsequently diagnosed with shunt malfunction and underwent shun revision. This resulted in complete resolution of her paroxysmal spells.

Conclusions: Although common differential diagnosis of brief paroxysmal stereotypic spells is usually seizures versus non-epilepsy behavioral spells, this patient’s case demonstrates clinical paroxysms caused by ICP fluctuations (plateau waves), which have to be taken into consideration when treating patients with possible ICP abnormality such as shunt malfunction.

Funding: Please list any funding that was received in support of this abstract.: No funding provided for this study/abstract.