Epileptic Disorders


7th Mediterranean Epilepsy Conference ; November 22-25, 2001, Athens, Greece - Video sessions Volume 4, numéro 1, March 2002

Video sessions

V 01

Video-EEG combined with EEG mapping

M.M.* Radionova, D.B. Chavdarov, R.S. Velizarova, I.G. Kojuharov, Medical University-Sofia, Bulgaria

Purpose: To avoid the difficulties of the simultaneous observation of the flowing multichannel EEG and the patients behavior on video EEG, and to present the EEG data as time series maps corresponding to the dynamics of the clinical manifestation.

Methods: In patients with different ictal phenomena, the EEG recording is divided in time series corresponding to the succeeding episodes of the ictal evolution. After artifact are eliminated, different techniques for signal processing and mapping presentation (series of momentary potential field maps, successive power maps, maps series of the field maximum, etc.) are applied. The simultaneous presentation of EEG and patient behavior is compared with the picture of the processed signal.

Results: The diagnostic importance of the video-EEG is in the simultaneous examination of the ictal EEG pattern and the clinical manifestation. The limitations of the technique are in the assessment of the EEG finding for the ictal evolution and the difficult correlation of EEG topography with the clinical manifestation. The EEG mapping analyses give the opportunity for different data processing and mapping presentations, according to duration and characteristic of the successive episodes of seizure evolution. The advantages of the video EEG mapping are: the opportunity to detect focal findings masked by the diffuse permanent or transient activity; to reveal any discrepancy between the suspected (according to the clinical evolution) and the real focus found with the EEG mapping; correlation between the movements' succession and the propagation of the discharges. The disadvantages of the technique are that it is an off-line and time-consuming processing, artifacts disturb the analyses, choice of an adequate mapping analysis.

Conclusions: Video-EEG combined with EEG mapping analyses makes the comparison between the epileptiform EEG phenomena and the patient's behavior easier, and provides an opportunity for a better understanding of the clinical-EEG relationships.

V 02

Stereotypical behavior of a patient with Williams syndrome

Derya Uluduz*, Veysi Demirbilek*, Aysin Dervent*. * Department of Neurology, Cerrahpasa University, Istanbul, Turkey

We present aspects of long-lasting stereotypical behaviour of a patient with Williams syndrome.

The patient is the second son, born in Nov., 1997, from a non-consanguinous, healthy couple. The first son was normal until he died at ten months of age, and diagnosed as having SIDS. There is a healthy sister, 11 years old. There are no other medical problems in the family. The patient developed normally until 6 months of age when he started to present the following behaviour (paroxsysmal, long-lasting, stereotypical events). His development then, has started to slow down and was regressing by the end of the first year of life. His vocabulary decreased from 20-25 words to 3-4 after that time, and his attention to the environment and toys was minimized and he no longer took any interest in independant walking. Sterotypes as turning around, preoccupation with turning objects became manifest. The condition was diagnosed as epilepsy and autism based upon on the parents' reports and an EEG, at 16 months of age. Behavioral therapy, in addition to VPA was started. The patient has started to present a slow improvement since then, in both motor and cognitive/psychosocial development, and the paroxsysmal events progressively decreased in frequency and severity. VPA was continued for a few months. The patient was referred to us a year ago. He had typical features of Williams syndrome. Genetic tests revealed missing material on chromosome 7, including the gene that makes the protein elastine. He has no autistic stereotypes now. He has moderate motor and mental deficiency which is improving and has good social contact. The present video-clip was recorded during his referral to our laboratory for a video-EEG in March 1999, when the patient was 16 months old. (Video): the episodes were about half to an hour's duration. They would be precipitated by frustration, following painful stimuli or during times of physical disturbances such as gastro-intestinal distress with nausea, vomiting and diarrhoea. He would become inattentive but conscious, would sterotypically flex his legs, squeeze his hand in between the legs, strain, hold his breath, utter some screaming sounds, perform bizarre mimics. He would pay interest to toys given but not sufficient to be distracted from the ongoing behaviour. His synchronized EEG was normal during these events. His inter-ictal EEG was normal during waking, it had some asynchronous and asymmetrical vertex-sharp-like activity in both fronto-central leads.

The patient was considered as having atypical masturbatory episodes which had been previously misdiagnosed as epilepsy. This case seems a good example of the wide-range variability of the abnormal paroxsysmal behaviour during infancy.

V 03

Epileptic negative myoclonus as a parodoxical effect of carbamazepine in benign rolandic epilepsy

M.A. Perez-Jimenez*, M.L. Ruiz-Falco f, M.C. Fournier del Castillc #. * Clinical Neurophysiology, f Neuropediatric, and # Neuropsychology Units. "Nifio Jesus" Hospital, Madrid, Spain

Introduction: We have documented the reversible worsening of the electroclinical picture in a little girl with an unusual presentation of benign epilepsy with centro-temporal spikes (BECTS) related to carbamazepine (CBZ) administration.

Case record: The patient is a 4 year and 3 month-old girl, studied by means of clinical observation, video-EEG map studies, neuropsychology and neuroimaging evaluations. At the age of 2 years and 9 months, she began to suffer from occasional, very brief diurnal, clustered, focal motor seizures (tonic/clonic), affecting her left hand and arm, eventually spreading to the mouth. Epileptiform activity was observed on the right central region, and CBZ was introduced. With middle-range serum CBZ levels, she experienced an increase of her usual seizures and the appearance of focal akinetic seizures lasting a few minutes. After further increasing the CBZ dosage, the clinical picture worsened, with appearance of transitory paresis of the left arm after awakening and sudden, intermittent left arm drops during the day. The video-EEG study revealed almost continuous benign epileptiform discharges of childhood, and slow-waves on the right hemisphere, at a maximum over the centro-parietal region, and repetitive epileptic negative myoclonus of the left arm. After CBZ tapering, and VPA introduction, the whole clinical picture reversed, without relapse after a follow-up of 1.8 year. Neurological, neuropsychological and MRI examinations were normal.

Conclusions: The recognition of unusual BECTS presentations, as well as the detection of a paradoxical effect of CBZ in these children, are critical to avoid erroneous therapeutic strategies. The early withdrawal of CBZ may prevent a more serious, atypical evolution.

V 04

A case presentation: alternating hemiplegia of childhood

Sema Saltik*, Turkan Uslu*, Aysun Kayaci*, Aysin Dervent*. *Department of Neurology, Cerrahpasa Medical Faculty, Istanbul, Turkey

A scene from a long-lasting episode characterized by bizarre movements in an infant with alternating hemiplegia of childhood will be presented here. Symptoms of increasing severity will be highlighted and they will be discussed with regard to the involvement of different modalities of nerve functioning.

V 05

Psychogenic status epilepticus in children and adolescents

M. Savani*, Vassilakin, C. Kotsalis, H. Bazigou, E. Paraskevoulakos, A. Papavasiliou. Department of Neurology, Pendeli Children, Hospital Athens, Greece

The aim of the study was to examine epilepsy features, psychiatric profile and social risk factors in children and adolescents with psychogenic status epilepticus (PSE). We present six patients with prolonged psychogenic seizures (PCS) >= 30 min or repetitive PCS simulating status epilepticus. They were three boys and three girls with mean age of 12.1 (5 to 15) years old. All had epilepsy and, in addition, one patient had right hemiplegia, one had speech delay and two had pervasive development disorder. There were three with symptomatic partial epilepsy, two with cryptogenic generalized and one with idiopathic generalized. They were all on anticonvulsants (ACVs). The EEGs prior to the PSE were abnormal. Some showed generalized slowing, others had lateralized slowing, and most of them had epileptic discharges. The brain MRIs were abnormal in two patients, one with left hemisphere atrophy and one with celebellar atrophy. Psychiatric assesment after PSE demonstrated the following profiles: three with pervasive development disorder, two with depression-anxiety disorder and one with obsessive-compulsive disorder. All patients received IV and/or rectal ACVs prior to the diagnosis of PSE. The diagnosis was confirmed via prolonged video-EEG monitoring, which established the absence of epileptogenic activity during alleged seizures. Provocation and placebo therapy techniques were used in some patients for confirmation of seizures under video-EEG. There were no adverse reactions with IV ACVs. In conclusion, we stress the occurrence of PSE in children and adolescents even in those cases with well established neurological and epilepsy syndromes, and the necessity of prompt diagnosis. Although psycogenic status epilepticus is unusual and less frequent in younger age groups compared to adults, the possibility of iatrogenic complications and delay in psychiatric management are the main risks of late diagnosis.

V 06

The significance of video-electroencephalography monitoring in differentiating epileptic and non-epileptic events

V. Kapitzoglou-Logothetis*, K. Garganis, J. Mylonas B'department of Neurology, Aristotelian University, Thessaloniki, Greece

The primary objective of the study was the differential diagnosis between epileptic seizures (ES) and non-epileptic events (NEE) in the era of long-term video-electroencephalography (EEG) monitoring. We studied 23 patients (8 males and 15 females) with ES and 25 patients (10 males and 15 females) with NEE, which included 16 patients with psychogenic and 9 patients with somatic events. Comparing the two groups, a younger age was observed for seizure onset in the ES group as opposed to the NEE group. Risk factors (febrile convulsions, perinatal injuries, head trauma) were present in the ES group. Clinical features of the epileptic seizures were simple or complex partial seizures, often with preceding aura, with or without secondary generalization. In the NEE group there was no aura. In this group, 64% of the events were psychogenic, manifesting as conversion reaction or other episodic behavioral disorders, and 36% were physiological or somatic, manifesting as somatic complaints. There was loss of consciousness in the epileptic event group (26%), while mild confusion was found in both groups. Postictal confusion was found in the ES group. Psychiatric disorders occurred prior to seizure onset in the NEE group, while in the ES group, the psychiatric disorders were observed after seizure onset. The event onset in the psychogenic NEE group was gradual, the termination was rather abrupt and the event duration variable, in contrast to the ES group. There was increased event frequency in the NEE group despite the antiepileptic drugs used, in contrast to the ES group. Neuroimaging findings were seen in 40% of the ES group, mainly in the hippocampal regions (30%), while in the NEE group the findings were of undetermined significance (33%). Interictal video-EEG abnormalities were seen in 87% of the ES patients and in none of the NEE patients. There were ictal-EEG abnormalities in all patients with epileptic seizures, in contrast with the NEE patients. In conclusion, in our study the contribution of the long term video-EEG monitoring was essential in confirming the diagnosis of non-epileptic events.

V 07

Non-epileptic seizures amongst patients referred for "intractable epilepsy": a video-EEG study

S. Giannakodimos*, F. Sekeri, G. Hatzidaki, C.E. Karageorgiou. Epilepsy Clinic, Neurology Department, General Hospital of Athens "G. Gennimatas", Athens, Greece

Objective: Non-epileptic seizures (NES) may account for considerable misdiagnosis of paroxysmal events. It is well known even from studies of candidates for epilepsy surgery that a small proportion of them in fact turns out to suffer from NES and not epilepsy. The increased use of video-EEG in the evaluation of patients with intractable epilepsies has helped the identification of NES amongst them. We present our video-EEG study regarding NES in patients referred to our center as "uncontrolled epilepsy".

Methods: Over the last three years, we have perform prolonged video-EEG monitoring in patients referred a diagnosis of uncontrolled epilepsy in order to capture seizures either for diagnostic reasons or as a part of presurgical evaluation. We tried to apply specific stimuli if seizures were provoked or we perform prolonged monitoring sessions with parallel AED reduction.

Results: Amongst those patients undergoing video-EEGs, there were 50 patients with uncontrolled seizures, including 6 surgical candidates. Nine patients (3 female) had non-epileptic seizures captured on video-EEG (none of them was a candidate for surgery). Their mean (range) age was 23.9 (17-30) years. Six patients had psychogenic seizures, two had sleep disorders, and one hypoglycemic episodes. None of these patients had concomitant epileptic seizures and in all, AED were successfully discontinued and appropriate treatment administered instead.

Conclusion: Non-epileptic seizures are a significant reason for intractability in patients seen in outpatient epilepsy clinics. Video-EEG must be performed in every case where there is suspicion of NES, because appropriate diagnosis has crucial therapeutic and prognostic consequences.

V 08

Temporal lobectomy for intractable epilepsy: surgical technique

E. Martin, M.D. Weinand. Division of Neurosurgery, Department of Surgery, Arizona Comprehensive Epilepsy Program, University of Arizona College of Medicine, Tucson, Arizona, USA

The operative technique as performed at the University of Arizona, for temporal lobectomy in intractable epilepsy may be divided into four main parts. Firstly, a frontal-temporal craniotomy is performed. The dura is opened in a cruciate fashion and the lateral temporal cortex is resected as a single specimen. From the anterior middle fossa, the lateral cortical specimen measuring 4.5 cm and 6.0 cm, in the hemispheres dominant and non dominant for language function, respectively. Secondly, the temporal horn is exposed along the trajectory of the Sylvian fissure and in the white matter in the plane of the sulcus, separating the superior and middle temporal gyri. The temporal horn is unroofed from posterior to anterior and the choroidal fissure is identified. Thirdly, further medial and lateral cortical dissection is performed. The operating microscope is introduced and the superior temporal gyrus white matter is removed from the Sylvian fissure using subpial dissection. The parahippocampal gyrus is resected. Fourthly, a complete amygdalohippocampectomy is performed. The amygdala is resected, during which the third cranial nerve is identified. With the choroidal fissure as the superior-most boundary, the hippocampus is resected en bloc and posteriorly with the CUSA (Cavitron Ultrasonic Surgical Aspirator), during which the posterior cerebral artery and cerebral peduncle are identified. The lateral temporal cortex and hippocampus are routinely preserved for basic neuroscience research in accordance with the institutional Human Subjects Committee protocol. The dura is closed and covered with biological collagen to facilitate dural healing. The bone flap is replaced using nylon suture. The temporlis fascia, galea and scalp are closed in layers. The patient is admitted to the intensive care unit overnight and is routinely discharged home within 1 to 3 days post-operatively. Anticonvulsant medication is maintained throughout the hospitalization and post-operatively for at least 2 years, even in seizure-free patients.

V 09

Ictal epileptogenic manifestation provoked by video-games

Stefano Ricci, Marta Piccioli, Dorothee Kasteleijn-Nolst Trenite Federico Vigevano. Epilepsy center, Neurol. Sciences, University of Rome la Sapienza, Italy, Neurology, MCA, Alkmaar, the Netherlands, Child Neurology, Bambino Gesu' Childrens' Hospital IRCCS, Roma, Italy

Objectives: Seizures provoked by video-games (VG) are frequently reported, but the precise clinical and electroencephalographic features are not yet well known. Furthermore, it is unknown whether these ictal manifestations are similar to the ones evoked by intermittent photic stimulation (IPS).

Methods: Out of a total of 29 children (12 M, 17 F) investigated with IPS and VG provocation, 16 (8 M, 8 F) showed generalised epileptiform activity (EA) during VG provocation. IPS and a total series of twelve video-games were tested in 13 of the 16 patients (5 M, 8 F). Simultaneous 3-way video-EEG recording, while playing each game for 5 minutes at a distance of 1 metre from a 50-Hz screen, made it possible to detect and compare signs and symptoms related to EA evoked by video-games and IPS.

Results: Seven patients had a history of partial seizures (idiopathic occipital lobe epilepsy) and 8 migrainous complaints. All patients presented ictal manifestations during both IPS and VG playing. Overall, the maximum duration of the EA during play was longer than during IPS. The vast majority of evoked EA was related to clinical signs. Three types of ictal events could be detected: absences, myoclonic jerks and focal seizures. The same signs, seen during IPS, could also be detected during VG playing; the EA lasting > 14 sec was always evoked by VG playing and clearly focal in origin.

Conclusions: Ictal manifestations during VG playing are basically similar to the ones evoked by IPS. VG playing, in addition, provokes longer lasting, focal seizures.

V 10

The clinical phenotype of typical absence seizures and absence epilepsies in childhood

A. Covanis

Aim: The purpose of this video presentation is to improve classification of absence seizures and add to their prognosis by using appropriate clinical and EEG criteria.

Methods: All children had prolonged sleep-wake video-EEG recordings after partial or complete overnight sleep deprivation. Hyperventilation was encouraged appropriately, according to the age group. Photosensitivity was assessed using a GRASS PS33 photostimulator and correct methodology.

Material: The video presentation will start with typical absence seizures in childhood and subsequently present cases, which are not "childhood absence epilepsy". These are: A. Absences in early infancy (< 3 years) and their characteristics: myoclonic versus non-myoclonic.

B. Myoclonic absence epilepsy (facial or other jerks).

C. Eyelid myoclonia with absences (Jeavon's syndrome).

D. Absences induced by photic stimulation.

E. Phantom absences.

F. Absences in juvenile myoclonic epilepsy.

G. Absences in self-induced photosensitive patients.

Conclusion: Lumping typical absence seizures under the heading "childhood absence epilepsy" discourages diagnostic precision and does not help geneticists to elucidate the molecular basis of «typical» absence epilepsy and syndromes. The prognosis of the above absence-spectrum varies and some of the absence syndromes are not expected to remit early.

V 11

Impairment of consciousness during hyperventilation in children: is it epileptic?

A. Covanis, A. loannidou, K. Skiadas, A. Vassou, N. Loli, V. Theodorou

In children, hyperventilation-induced high amplitude rhythmic delta activity (HIHADA) is considered normal if spikes are not intermixed.

Purpose: To evaluate the significance of absence-like episodes observed during HIHADA in some epileptic and non-epileptic children, normal or subnormal and to discuss possible underlying mechanisms.

Methods: Absence-like episodes were observed in 17 non-epileptic and 14 epileptic children (77% girls), aged 2 to 13 years. Of the 17 non-epileptic children, 14 were evaluated for headaches, "Tummy aches": and "vague looks". Family history was positive for epilepsy in four children. The 14 epileptic children had idiopathic generalized or partial epileptic syndromes/epilepsies and exhibited unresponsive behavior during hyperventilation (HV), at different stages of their assessment. All children had video-EEG recordings. Hyperventilation was encouraged for 3 minutes or longer. Blood samples for glucose, acid-base balance and ionized calcium (Ca2+) were taken in 19 children, prior to HV and during HIHADA.

Results: In all children, HIHADA was recorded in 5 to 20 second bursts. The associated absence-like episodes consisted of cessation of over-breathing, restlessness, automatisms, yawning, unresponsiveness to verbal recall, or inability to recall a word or a sequence of words after the event. Five non-epileptic children received valproate (VPA) for 3 months and the EEG became normal in three children. The ionized Ca2+ in 12 epileptic and in 7 non-epileptic children, was 0.82 ± 0.35 versus 0.94 ± 0.30 mmol/l during HIHADA and 1.01 ± 0.30 versus 1.09 ± 0.20 mmol/l prior to HV respectively (Normal: 1.10-1.35 mmol/l).

Conclusions: Absence-like episodes are considered a borderline epileptic phenomenon, related to typical absences, which do not occur spontaneously and have a benign course. Treatment is not needed. The underlying trigger factor may be the low ionized Ca2+, induced by hyperventilation.

V 12

West Syndrome and autism

A. Dervent

Istanbul Univ., Cerrahpasa Med. Fac., Neurology Dept, Child Neurology Unit

The majority of the studies on West Syndrome (WS) are oriented towards the clinical, imaging and EEG expressions of spasms and partial seizures, as well as types of hypsarrhythmia, with regard to etiological, therapeutic and prognostic implications. Non-epileptic manifestations such as behavioral disturbances and cognitive problems, that are frequently encountered in these patients, are, however, commonly overlooked by the epileptologist, and are often referred to related specialties for consultation of either the etiology, or more, the management Yet, there are some patients with WS whose spasms are either preceeded or immediately followed by either apparently non-epileptic motor manifestations such as dyskinesias, simple repetitive acts, trans-like states mimicking atypical absence seizures, and/or ritualistic, complicated behavioral changes. These events may take place within a cluster of epileptic spasms. Sometimes, partial seizures may also be present and increase the complexity of interpretation. Minor spasms during such an episode may be subtle and go unnoticed if the video-EEC is not carefully analyzed.

Whatever the nature of the motor and psychological phenomena accompanying the spasms, they seem to be closely time-linked to the inter-spasm period. While some patients may outgrow such behavioural patterns after infancy, others may develop established autism in addition to their epilepsy.

This subject seems to deserve further attention from a pathophysiological point of view, and possible cortico-subcortical circuits may be questioned in the relation of seizures, spasms and stereotypes.

A video-display of some such episodes occurring in our patients with WS is presented here.