Nosological Problems of Myoclonic Epilepsies in Childhood and Adolescence

Abstract

SUMMARY An attempt is made to clarify the confusion over the classification of the myoclonic epilepsies of childhood. Six types of seizure are described, the classification being based on clinical and electroencephalographic findings. The types of myoclonic epilepsy are infantile spasms, myoclonic astatic epilepsy, myoclonic absence, myoclonic epilepsy of childhood, myoclonic epilepsy of adolescence and photomyoclonic epilepsy, the last being subdivided into myoclonic jerks and eyelid myoclonia. Synonyms are given for all types, based on the major papers in the literature over the last 16 years. The similarity of infantile spasms and myoclonic astatic epilepsy is discussed, as are the so‐called ‘Lennox’ and ‘Lennox‐Gastaut’ syndromes. RÉSUMÉ Problèmes nosologiques des épilepsies myocloniques de l'enfance et de l'adolescence Une tentative est faite de clarifier la classification des épilepsies myocloniques de l'enfance. Six types de crises sont décrites, la classification étant basée sur les données cliniques et électroencéphalographiques. Les types d'épilepsies myocloniques sont les spasmes infancies, l'épilepsie myoclonique astatique, l'absence myoclonique, l'épilepsie myoclonique de l'enfance, l'épilepsie myoclonique de l'adolescence et l'épilepsie photomyoclonique, cette dernière étant subdivisée en secousses myocloniques et myoclonic des paupiéres. Des synonymes sont indiqués pour tous les types à partir des articles principaux de la littérature des 16 dernières années. L'identification des spasmes infantiles et de l'épilepsie myoclonique astatique est discutée comme le sont les syndromes dits de ‘Lennox’ et de ‘Lennox‐Gastaut’. ZUSAMMENFASSUNG Nosologische Probleme myoklonischer Epilepsie bei Kindern und Heranwachsenden Es wird der Versuch unternommen, die Unklarheiten bei der Klassifizierung der myo‐klonischen Epilepsien des Kindesalters zu beseitigen. Sechs Anfallstypen werden beschrieben, wobei die Klassifizierung auf klinischen und elektroencephalographischen Befunden basiert. Die Typen der myoklonischen Epilepsie sind: BNS‐Krämpfe, myoklonisch‐astatisches Anfallsleiden, myoklonische Absencen, myoklonische Epilepsie im Kindesalter, myoklonische Epilepsie im frühen Erwachsenenalter und photosensible myoklonische Epilepsie, die letztere wird noch unterteilt in myoklonische Anfälle und Augenlidmyo‐klonien. Für alle Typen werden Synonyma angegeben, die der einschlägigen Literatur der letzten 16 Jahre entnommen wurden. Es wird über die Ähnlichkeit der BNS‐Krämpfe mit den myoklonisch‐astatischen Anfällen diskutiert, sowie über die sogenannten ‘Lennox’ und ‘Lennox‐Gastaut’ Syndrome. RESUMEN Problemas nosológicos de las epilepsias mioclónicas de la infancia y adolescencia Se hace un intento para clarificar la confusión sobre la clasificación de las epilepsias mioclónicas en la infancia. Se describen seis tipos de crisis, cuya clasificación está basada en los hallazgos clínicos y electroencefalográficos. Los tipos de epilepsia mioclónica son espasmos infantiles, epilepsia mioclónica astática, ausencia mioclónic...

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

“…(7), M (6), PNESs (7) GTCSs (14), MM (12), As (15), PNESs (4) GTCSs (2), MM (4), FSs (4) Refractory to AED GTCSs (11), EMs (17) GTCSs (9), EMs (2) GTCSs (4) We identified 31 patients (in group 1) with EMs with or without absences associated with GTCSs and mild myoclonias that were limited to the upper body, neck, or head. They had well-defined electroclinical features similar to those first described by Jeavons and then a few other authors [2,3,9,11,25].…”

“…Eyelid myoclonia without or with absences (EMA) was first documented in 1937 by Radovici and colleagues as a case report [1], and, subsequently, the main features of this condition were described by Jeavons in 1977 [2]. Although EMA is considered well defined with its clinical and electrophysiological features described by several authors [3][4][5][6][7][8][9][10][11], its place in the epilepsy classifications is still debated.…”

“…It is associated with a brief 3-6 Hz generalized discharges of spike-and-wave activity in the electroencephalogram (EEG). Eyelid myoclonias (EMs) are provoked by photic stimulation and are completely abolished when the eyes are closed in total darkness [2,[15][16][17][18].…”

Eyelid myoclonia with absences (Jeavons syndrome): still an overlooked epilepsy syndrome. Comments to Covanis review in this issue of Journal of Epileptology

“…T he epileptic phenotype featuring eyelid myoclonia (EM) and absences at eye closure plus photosensitivity (EMA or ELMA) was first reported more than 80 years ago by Radovici et al (1932) and then fully described by Jeavons in 1977. EMA typically starts in childhood with long-lasting and often drugresistant course with high risk of recurrence of generalized tonic-clonic seizures (GTCS).…”

Outcome of pediatric epilepsies in adulthood

“…These publications comprised several methodological problems or bias: (1) some encompassed different epileptic syndromes behind the terms "absence seizures" and "petit mal" and included without clear distinction a mixture of individuals with CAE and other disorders (Lees and Liversedge, 1962;Charlton and Yahr, 1967;Bouma et al, 1996); (2) in other studies, although they have well distinguished different syndromes with absences, the inclusion criteria were either variable from one study to another, or too inaccurate (Bouma et al, 1996;Giannakodimos and Panayiotopoulos, 1996). Another example is the syndrome of "absence epilepsy of early childhood" characterized by an onset before the age of 5 years and that covers a heterogeneous group of epileptic disorders (Doose, 1994); (3) newly described epileptic syndromes such as eyelid myoclonia with absences and perioral myoclonia with absences (Jeavons, 1977;Panayiotopoulos et al, 1995) were not individualized in older studies; (4) the duration of follow-up in many studies was often insufficient after cessation of absence seizures as generalized tonic-clonic seizures or myoclonic jerks may appear later in life (Currier et al, 1963;Gibberd, 1966;Gastaut et al, 1986;Bouma et al, 1996;Wirrell et al, 1996); and (5) therapeutic advances have also probably contributed to this heterogeneity, particularly when old and more recent series were mixed (Bouma et al, 1996). Another example is the syndrome of "absence epilepsy of early childhood" characterized by an onset before the age of 5 years and that covers a heterogeneous group of epileptic disorders (Doose, 1994); (3) newly described epileptic syndromes such as eyelid myoclonia with absences and perioral myoclonia with absences (Jeavons, 1977;Panayiotopoulos et al, 1995) were not individualized in older studies; (4) the duration of follow-up in many studies was often insufficient after cessation of absence seizures as generalized tonic-clonic seizures or myoclonic jerks may appear later in life (Currier et al, 1963;Gibberd, 1966;Gastaut et al, 1986;Bouma et al, 1996;Wirrell et al, 1996); and (5) therapeutic advances have also probably contributed to this heterogeneity, particularly when old and more recent series were mixed (Bouma et al, 1996).…”