doi:10.1684/epd.2011.0449 4M1 H2L Canada Québec, Montréal, East, Sherbrooke 1560 Notre-Dame), (Hôpital Montréal de Université Hospitalier Centre Nguyen D.K. Correspondence: plpi iod o.1,N.3 etme 2011 September 3, No. 13, Vol. Disord, Epileptic e words: Key epilepsy. lobe frontal sequences] of semi- suggestive other with features associated ologic when potential a particularly as seizures, epilepsy myoclonic fronto-polar of consider cause to clinicians for need empha- the case seizures, Our sizes epilepsy. tonic-clonic fronto-polar left generalised symptomatic postic- a and to myoclonic due associated likely brain her were with as MRI well events and as somatosensory aphasia, days tal patient’s 14 in the for sensations that monitoring abnormal revealed video-EEG of Continuous episodes arms. stereotyped both with presented years 30 ABSTRACT 2 1 Keezer R. Mark epilepsy myoclonic juvenile as masquerading epilepsy Fronto-polar eevdDcme 4 00 cetdJl ,2011 5, July Accepted 2010; 14, December Received Canada Hospital agKo Nguyen Khoa Dang oms ieysfe rmasymp- a epilepsy. fronto-polar from left suffer tomatic likely most to found later was but JME, with con- sistent were investigations and tation presen- clinical a initial present whose patient we value, pos- localising their sible of contribute and seizures understanding to myoclonic evolving effort our an to In (Leppik, 2003). (JME) epilepsy juvenile myoclonic is the which of epilepsies, important most myoclonic of the includ- diseases ing system nervous several central the mani- of important festation an is Myoclonus ezrsta h eeoe tage at developed she refractory that for seizures service epilepsy our to referred was woman 49-year-old A study Case eateto erlg,Cnr optle nvriéd otél Montreal, Montréal, de Université Hospitalier Centre Neurology, of Department and Institute Neurological Montreal Neurosurgery, and Neurology of Department lnclcmetr ihvdosequences video with commentary Clinical plpi iod21;1 3:317-20 (3): 13 2011; Disord Epileptic oa igoe ihjvnl ycoi plpyfrover for epilepsy myoclonic juvenile with diagnosed woman A – ycou,eies,fotllb,jvnl ycoi epilepsy myoclonic juvenile lobe, frontal epilepsy, myoclonus, 1 enMr Saint-Hilaire Jean-Marc , 2 la.Acrigt h ain and patient the to initially the According not clear. although was this GTCS, of the significance her to of prior onset just forward additional running patient the an of history was long-standing There seizure into (GTCS). tonic-clonic evolved generalised invariably a and conscious- of ness level her in a decrease by followed or soon was arms a which legs, trunk the with of jerk began myoclonic seizure convulsive typical patient’s Our adoles- childhood. dur- ing seizures of isolated possibly experienced who end sisters two the and cence at which remitted seizures from epileptic suffered recurrent included who history grandmother a family unremark- develop- Her were able. and histories peri-natal mental Her 14. 2 , Pbihdwt video with [Published 317 M.R. Keezer, et al.

her family, the postictal period was without any local- MRI brain revealed a cystic lesion of the left fronto- ising symptoms or signs. Her seizures recurred as marginal and inferior transverse fronto-polar gyri with frequently as every two months during adolescence surrounding gliosis (figure 2). Ictal SPECT was unre- but eventually waned to a handful per year (includ- markable although the interictal SPECT demonstrated ing a two-year seizure-free period). The patient was a mild hypoperfusion of the left frontal and temporal also known to have isolated myoclonic jerks which lobes. occurred several times per week but without any par- Based on the clinical, EEG and neuroimaging findings, ticular diurnal pattern. Prior routine EEGs had demon- the patient was diagnosed with a left fronto- strated bursts of 4-7-Hz generalised spike-and-wave polar epilepsy syndrome presenting with prominent activity which occasionally had a left temporal predom- myoclonus as well as stereotyped motor agitation and inance. A previous CT scan of the brain was reportedly somatosensory phenomena with postictal aphasia. normal. Given the prominent history of myoclonus and Her seizures were eventually controlled with topira- convulsions, lack of aura, age of onset and initial EEG mate at 200 mg per day. findings, the patient was diagnosed with JME. In 2006 (coinciding with menopause), her seizure Discussion condition worsened with almost monthly convulsions prompting several antiepileptic drug trials (valproate, In the case we have presented, the initial clinical pre- topiramate, clobazam, phenytoin, phenobarbital and sentation, EEG findings and normal brain scan were carbamazepine). She also reported a novel type of strongly suggestive of JME. It was the recent exacerba- spell characterised by abnormal sensations in both tion of her seizure condition along with the develop- arms, extending from the fingers to the elbows without ment of new and atypical somatosensory events which an associated alteration in her level of consciousness. prompted admission to hospital for prolonged video- These were quite rare except for a five-day period dur- EEG telemetry and high-resolution MR imaging. Only ing which she experienced these sensations daily. She then was it suspected that the patient most likely suf- was eventually admitted to our video-EEG telemetry fered from a symptomatic left fronto-polar epilepsy unit to better define these spells as well as her epileptic syndrome. Of course, definitive proof in the form of syndrome. invasive electrographic recordings or seizure freedom Continuous video-EEG monitoring for 14 days revealed following lesionectomy is not available due to the a normal background rhythm but frequent interictal patient’s good response to medical therapy. epileptiform discharges in the form of two-second We consider it unlikely that our patient had simul- bursts of generalised 2-3-Hz spike/polyspike-and-wave taneous JME and symptomatic frontal lobe epilepsy. activity which was increased by hyperventilation and The co-occurrence of the myoclonus, focal semiologic intermittent photic stimulation. Frequent myoclonus features and electrographic discharges strongly sug- of the legs, arms and trunk was observed and elec- gest that they are due to a single epileptic process. trographically associated with two to three-second We also consider it unlikely that all of her findings bursts of 2.5-3-Hz generalised spike-and-wave activity. could be accounted for by an idiopathic generalised On two occasions, this myoclonus was followed by epilepsy. Firstly, while focal electrographic discharges an alteration in the patient’s level of consciousness (Usui et al., 2005), even evolving from an initial gene- and a brief attempt to lunge or run forward which was ralised epileptiform discharge (Williamson et al., quickly interrupted by a GTCS. These seizures lasted 2009), have been described in JME, the observed left approximately 60 seconds and were electrographi- fronto-temporo-central discharges and the postictal cally associated with the same 2.5-3-Hz generalized aphasia corresponded very well with the location of spike-and-wave activity. Towards the end of her hospi- the described lesion. In addition, although focal semi- talisation, and only after the discontinuation of all of ologies have been described in JME, they are typically her antiepileptic medications, a third type of clinical simple versive head movements or posturing (Usui event was observed. On this occasion the patient et al., 2005) and do not include stereotyped motor agi- had a myoclonic jerk of the right leg associated with tation, somatosensory phenomena or postictal apha- a three-second burst of generalised spike-and-wave sia. An alternate hypothesis would be that our patient activity. Seven seconds later, the patient experienced did in fact have JME but that it had been clinically a second myoclonic jerk but also dysesthesias of both and electrographically modified by the fronto-polar hands which was soon followed by an expressive lesion, therefore allowing for the focal semiologic and aphasia. Electrographically, this event was associated electrographic findings. We believe that such network with left fronto-temporo-central sharply contoured plasticity in JME is not well established and there- rhythmic theta activity which soon generalised but fore do not support this hypothesis. Finally, although maintained left hemispheric predominance (figure 1, rare, photoparoxysmal responses have been described see video sequence). in occipital, parietal as well as frontal lobe epilepsy

318 Epileptic Disord, Vol. 13, No. 3, September 2011 Fronto-polar epilepsy with myoclonic seizures

A B C Fp1-F7 F7-T3 T3-T5 T5-O1 Fp1-F3 F3-C3 C3-P3 P3-O1 Fp2-F4 F4-C4 C4-P4 P4-O2 Fp2-F8 F8-T4 T4-T6 T6-O2

V ECG 100 µ 100 1 second * D Fp1-F7 F7-T3 6 seconds 10 seconds T3-T5 T5-O1 Fp1-F3 F3-C3 C3-P3 P3-O1 Fp2-F4 F4-C4 C4-P4 P4-O2 Fp2-F8 F8-T4 T4-T6 T6-O2 ECG

Figure 1. Electroencephalogram with (A) interictal generalised 2-3-Hz spike-and-wave discharges which were increased by hyper- ventilation and intermittent photic stimulation; (B) myoclonus (black arrow) with associated generalised spike-and-wave discharges; (C) the onset of a GTCS preceded by myoclonus (black arrow) and lunging with associated generalised spike-and-wave discharges; (D) an epileptic seizure characterised by recurrent myoclonus with associated generalised spike-and-wave discharges (black arrows) followed by hand dysesthesias (*) and postictal aphasia with associated left fronto-temporo-central sharply contoured rhythmic theta activity. Low and high frequency filters were set at 0.5 and 35 Hz, respectively.

(Seshia and Carmant, 2005) and, therefore, we do not In summary, we present a patient who initially pre- believe that its presence challenges the diagnosis of a sented with a syndrome suggestive of JME but was symptomatic frontal lobe epilepsy. later found to suffer from a symptomatic fronto- There has been only one previous report of myoclonic polar epilepsy. Definitive proof in the form of seizures occurring in the context of a symptomatic invasive electrographic recordings or post-surgical frontal lobe epilepsy (Cho et al., 2010). It is perhaps of seizure freedom is not available. Our case empha- some interest that frontal lobe dysfunction in patients sizes the need for clinicians to consider fronto- with JME has been demonstrated in a number of recent polar epilepsy as a potential cause of myoclonic neuropsychological, FDG-PET and dense array electro- seizures when associated with other semiologic or encephalography studies (Holmes et al., 2010). In fact, electrographic features suggestive of frontal lobe it has been previously suggested that asymmetric epilepsy.
activation via the frontal lobes of the basal ganglia, sup- plementary motor area or prefrontal area can result in Disclosure. myoclonus, although this remains to be proven (Cho None of the authors has any conflict of interest or financial et al., 2010). support to disclose.

Epileptic Disord, Vol. 13, No. 3, September 2011 319 M.R. Keezer, et al.

Figure 2. Brain MRI demonstrating a cystic lesion of the left fronto-marginal and inferior transverse fronto-polar gyri (white arrows).

Legend for video sequence References

Video sequences corresponding to the EEG record- Cho YW, Yi SD, Motamedi GK. Frontal lobe epilepsy may ings illustrated in figure 1, sections (B), (C) and (D). present as myoclonic seizures. Epilepsy Behav 2010; 17: B) Myoclonus with associated generalised spike- 561-4. and-wave discharges. C) Onset of a GTCS preceded by myoclonus Holmes MD, Quiring J, Tucker DM. Evidence that juve- and lunging with associated generalised spike-and- nile myoclonic epilepsy is a disorder of frontotem- wave discharges. poral corticothalamic networks. Neuroimage 2010; 49: 80-93. D) An epileptic seizure characterised by recurrent myoclonus with associated generalised spike-and- Leppik IE. Classification of the myoclonic epilepsies. Epilepsia wave discharges followed by hand dysesthesias 2003; 44: 2-6. and postictal aphasia with associated left fronto- temporo-central sharply contoured rhythmic theta Seshia SS, Carmant L. Visual-sensitive epilepsies: classifica- activity. tion and review. Can J Neurol Sci 2005; 32: 298-305.

Key words for video research Usui N, Kotagal P, Matsumoto R, Kellinghaus C, Lüders HO. on www.epilepticdisorders.com Focal semiologic and electroencephalographic features in Etiology: gliosis patients with juvenile myoclonic epilepsy. Epilepsia 2005; 46: Phenomenology: myoclonic seizure, focal seizure 1668-76. not otherwise specified, tonic-clonic seizure Localization: frontal lobe (left) Williamson R, Hanif S, Mathews GC, Lagrange AH, Abou- Syndrome: focal non-idiopathic frontal (FLE) Khalil B. Generalized-onset seizures with secondary focal evolution. Epilepsia 2009; 50: 1827-32.

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