Featured Case - March 2015

Contributed by:
Dragos A. Nita, MD, PhD, FRCPC
The Hospital for Sick Children
Toronto, Canada

Clinical Presentation:

A 14 year-old girl presented with a 3-year history of generalized tonic clonic seizures mainly on awakening. She was also noted to have brief staring episodes during the daytime associated with “her eyes flickering” when she looked at a light. Myoclonic jerks were not observed. Both her GTC seizures and the staring episodes were initially well controlled on valproic acid monotherapy; however, she developed a skin reaction concerning for Stevens-Johnson syndrome and was switched to levetiracetam. Levetiracetam resulted in good control of her GTC seizures, but her daily staring episodes recurred. Her neurologic examination and a high-resolution brain MRI were normal. A routine scalp EEG demonstrated the findings illustrated in Figures 1 & 2.

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Figure 1: Routine EEG in an A-P longitudinal bipolar montage obtained during wakefulness demonstrating 3-4 Hz generalized epileptiform discharges, correlating clinically with a brief staring episode associated with eye blinking. Arrows indicate occipital lead-in prior to the onset of generalized epileptiform discharges. Calibration bars: horizontal 1 second, vertical 100 uV.

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Figure 2. Routine EEG in an A-P longitudinal bipolar montage obtained during wakefulness demonstrating photoparoxysmal responses at 6 Hz and 8 Hz photic stimulation. Calibration bars: horizontal 1 second, vertical 100 uV.

Answer & Discussion:

The patient’s clinical history and electrographic features are consistent with a syndrome of eyelid myoclonia with or without absences, also known as Jeavons syndrome. Although Jeavons syndrome is not recognized as a distinct epilepsy syndrome in the 2010 ILAE classification of seizures it can be classified under “absence with special features – eyelid myoclonia”. Jeavons syndrome is a lesser-known epilepsy syndromes of unknown etiology defined by a triad of eyelid myoclonia, eye-closure induced seizures or occipital paroxysms, and photosensitivity (Jeavons, 1977). A classic EEG feature is the presence of a spiky posterior dominant alpha rhythm induced by active or passive eye-closure that rapidly generalizes evolving into generalized 3-4 Hz spike or polyspike-wave discharges. Eyelid myoclonia often coincides with bi-occipital polyspike and wave epileptiform discharges, with or without generalized polyspike and wave discharges (Viravan, 2011). Although eyelid myoclonia is the most common seizure type in patients with Jeavons syndrome, it has also been reported in other idiopathic generalized epilepsies of both cryptogenic and symptomatic etiology (Panayiotopoulos, 2005). Photosensitivity may decrease with age (Giannakodimos, 1996). It has been hypothesized that the mechanism of seizure generation in Jeavons syndrome involves a focal epileptic occipital cortex that triggers generalized epileptic discharges (Viravan, 2011). Although GTC seizures are usually well controlled by monotherapy with a variety of drugs including valproic acid, ethosuximide and levetiracetam, eyelid myoclonias are usually resistant to treatment, responding only partially to benzodiazepines. Jeavons syndrome may be mistaken for childhood absence epilepsy or juvenile absence epilepsy, other forms of genetic or idiopathic generalized epilepsies, or even facial tics.

References:

Jeavons PM. (1977) Nosological problems of myoclonic epilepsies in child-hood and adolescence. Dev Med Child Neurol 19:3–8.
Berg AT, Berkovic SF, Brodie MJ, Buchhalter J, Cross JH, van Emde Boas W, Engel J, French J, Glauser TA, Mathern GW, Moshé SL, Nordli D, Plouin P, Scheffer IE. (2010) Revised terminology and concepts for organization of seizures and epilepsies: report of the ILAE Commission on Classification and Terminology, 2005-2009. Epilepsia 51(4):676-85.
Panayiotopoulos CP. (2005) Syndromes of idiopathic generalized epilepsies not recognized by the International League Against epilepsy. Epilepsia 46:57–66.
Viravan S, Go C, Ochi A, Akiyama T, Carter Snead O III, Otsubo H. Jeavons syndrome existing as occipital cortex initiating generalized epilepsy. (2011) Epilepsia  52:1273–1279.
Giannakodimos S, Panayiotopoulos CP. Eyelid myoclonia with absences in adults: a clinical and video-EEG study. (1996) Epilepsia 37:36–44.