Paroxysmal eyelid movements in patients with visual-sensitive reflex seizures.

Abstract

Paroxysmal eyelid movements (PEM) are non-epileptic episodes characterized by eyelid closure, upturning of the eyes, and rapid eyelid flutter. The aim of this study was to report clinical and EEG data of patients with PEM and its relationship with visual sensitivity. We studied 26 patients with epilepsy (12 males and 14 females; mean age: 14.0±6.9 years) who presented PEM. The epilepsy was idiopathic generalized (eight cases), idiopathic focal (six cases), symptomatic focal (five cases), and reflex epilepsy (seven cases). PEM and blinking were analysed by video-EEG recordings at rest and during intermittent photic stimulation, pattern stimulation, and TV watching. Blink rate was evaluated during three different conditions: at rest, during a TV-viewing period, and at the occurrence of PEM. Analysis of variance (ANOVA) was used for statistical comparisons. Repeated episodes of PEM were recorded in all patients. The frequency of PEM ranged from 8 to 12.5 Hz (average: 9.6±1.5). PEM were accompanied by a significant increase in blinking compared to the rest condition and TV watching (blink rate: 56.5±21.1 vs 25.0±16.2 vs 11.3±11.8, respectively; p<0.0001). Photoparoxysmal EEG responses (measured as sensitivity to photic stimulation) were found in 25 cases, associated with pattern sensitivity in 22; only one patient was sensitive to pattern but not photic stimulation. Visually-induced seizures were recorded in 20 cases, triggered by both stimuli (photic and pattern stimulation) in 11 patients; seizures were triggered by pattern stimulation (but not photic stimulation) in five, photic stimulation (but not pattern stimulation) in three, and TV watching (but not photic or pattern stimulation) in one. Epileptic eyelid myoclonia was noted in 17 patients. The coexistence of PEM, photoparoxysmal EEG responses, increased blinking, and epileptic eyelid myoclonia suggests an underlying dysfunction involving cortical-subcortical neural networks, according to the recent concept of system epilepsies. [Published with video sequences].