Jeavons syndrome existing as occipital cortex initiating generalized epilepsy

Abstract

Summary Purpose: Jeavons syndrome (JS) is one of the underreported epileptic syndromes characterized by eyelid myoclonia (EM), eye closure–induced seizures/electroencephalography (EEG) paroxysms, and photosensitivity. JS has been proposed as idiopathic generalized epilepsy (IGE) because of normal posterior dominant background activity and paroxysmal generalized ictal epileptiform discharges (EDs). However, we noticed subtle occipital EDs preceding EM and interictal posterior EDs using digital video‐EEG. We studied clinical and EEG findings in JS to determine the specific occipital lobe relation to this “eye closure–induced” reflex IGE. Methods: We identified 12 children who met the diagnostic criteria of JS from January 2004 to April 2009 at the Hospital for Sick Children, Toronto, Canada. All patients had EM captured by video‐EEG. We reviewed and described ictal EEG patterns, interictal abnormalities, and demographics, clinical, and neuroimaging findings. Key Findings: All patients but one were female (92%). Age at seizure onset ranged from 1.5 to 9 years, with a mean age of 4.9 years. Six patients (50%) were previously diagnosed as having absence epilepsy and 10 patients were on antiepileptic medications. All 12 patients had normal posterior dominant alpha rhythm, reactive to eye opening and closure. Spiky posterior alpha activity was noted with sustained eye closure in six patients (50%). Interictally, there were generalized EDs found in 10 patients (83%); four of them also had focal interictal EDs over the posterior head region. Eleven patients (92%) had evidence of focal posterior ictal EDs. EM and/or paroxysmal EDs were induced by photic stimulation in 9 (75%) and hyperventilation in 7 (58%). Significance: We observed two neurophysiologic findings in JS: (1) focal interictal EDs from posterior head region; and (2) predominant focal posterior ictal EDs preceding generalized EDs. Further clinical observations of seizures induced by eye closure, photic stimulation, and hyperventilation along with EEG paroxysms would raise the possibility of the occipital cortex initiating generalized epilepsy network involving the brainstem, and thalamocortical and transcortical pathways in JS.

Eyelid myoclonia seizures in adults: An alternate look at the syndrome paradox

“…Sharp alpha rhythms and isolated occipital spikes can be seen in EMA [35]. As shown in recent studies, the occipital cortex plays a role in pathophysiology of some epilepsies in which ECLS, fixation-off sensitivity (FOS), and photosensitivity are the initiating factors [36][37][38]. However, interestingly, we also saw frontal focal abnormalities in 4 patients with pure EMA (Fig.…”

Prevalence and characteristics of visual aura in idiopathic generalized epilepsy

“…Although focal EEG abnormalities in posterior regions have recently been reported [9], their possible clinical counterpart, namely visual aura, was not reported in association with the EMA syndrome, which is a unique syndrome. We found that EMA is common among the IGE patients having visual aura.…”

Reflex epileptic mechanisms in humans: Lessons about natural ictogenesis

“…In the vast majority of cases, ECS is only seen with lights on, and it has, therefore, been suggested that the response is generated in the visual cortex, supported by the EEG [14]. However, the eyelid myocloni of ECS are not invariably accompanied by SW discharges [15].…”