Blinking and eyelid myoclonia: Characteristics and correlations of eyelid movements

PURPOSE Eyelid myoclonia (EM) is considered a seizure type and has been described in several epileptic conditions. Previous studies reported that EM are precipitated only by slow eye closure, but little is known about the characteristics of blinking in patients with EM seizures and differences in precipitation of EM by different kinds of eye closure. We analyzed by video-EEG the characteristics of blinking and eye closure in these patients. METHOD Twenty patients with EM had a video-EEG protocol with eyelid sensors. Semiology and rate of blinking and EM were analyzed. Statistical analysis was performed and p-values <0.05 were considered significant. RESULTS Seventeen cases (mean age 20.7, range 3-35) were women, 10 had EM as the main seizure type and between the others, all, but one, had criteria to Juvenile Myoclonic Epilepsy. All patients presented EM, 18 spontaneously during awake, 10 on eye closure and one only during intermittent photic stimulation. EM assumed the form of flicker, flutter or jerk, accompanied by generalized discharges, spiky posterior alpha, theta rhythm or absence of any EEG abnormality. Analysis of the characteristics of blinking had no statistics differences between patients and healthy subjects. The rate of blinks and EM increased during speech and decreased during reading. EM never occurred during blinking or in the dark. CONCLUSIONS Despite normal physiology of blinking, EM can manifest as jerk, flicker or flutter, with or without EEG abnormalities and independently of IPS, suggesting that eye closure sensitivity seems to include both, a motor and a visual component.