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***EPILEPSY
Journal of the Neurological Sciences
Article in Press, Corrected Proof - Note to users
1H-MR spectroscopy: a promising method in
distinguishing subgroups in temporal lobe epilepsy?
Hammena, H. Stefana, , , E. Paulia,
Proton MR
spectroscopy offers an additional noninvasive method
of supporting focus lateralization in patients with intractable temporal lobe
epilepsy. In this study involving 57 patients, the ability of multivoxel 1H-MRS to differentiate between mesial and lateral TLE was investigated in addition to its
ability to lateralize the epileptogenic focus.
Temporal lobe epilepsy (TLE) was classified into mesiobasal
or lateral temporal lobe epilepsy according to the results of preoperative
diagnostics including neurological and neuropsychological examinations,
video-EEG monitoring and high resolution MRI. 1H-MR-spectroscopy (1H-MRS)
showed that pathological changes in the mesial
temporal lobes indicate a predominance in different
parts of the ipsilateral temporal lobe (hippocampal and parahippocampal
areas) correlating to the clinically defined groups. In addition, mesiobasal TLE tends to have higher concomitant contralateral abnormalities. Our results reveal that
1H-MRS is able to distinguish between mesiobasal and
lateral pathologies in patients with TLE and represents a useful tool for
noninvasive TLE classification.
Clinical Neurophysiology, In Press
Callosal role in
generation of epileptiform discharges: quantitative
analysis of EEGs recorded in patients undergoing corpus callosotomy
Atsuko Matsuo, Tomonori Ono, Hiroshi Baba and Kenji Ono
Objective:
Corpus callosotomy tends to decrease seizure
frequency and severity rather than transforming the seizure pattern from a
generalized form into a lateralized or a partial one. The finding implies that
bisection of the corpus callosum (CC) disrupts the epileptogenicity itself. In order to gain further insight
into the possible role played by the CC in intractable generalized epilepsy,
quantitative analyses of long-term EEGs were performed. Methods: Analyses were made of epileptiform discharges contained in the pre- and
postoperative long-term EEGs in 7 patients who had an anterior callosotomy for intractable epilepsy. The duration, number,
and amplitude of all epileptiform burst activities
were measured and statistically analyzed.
Results: After callosotomy, the total number
of epileptiform burst activities, mean duration, and
the total number of spike discharges decreased significantly. The two
hemispheres could be divided into dominant and non-dominant ones as to the
quantity of the residual epileptiform
discharges. Conclusions: Corpus callosotomy unevenly reduced preoperative epileptiform discharges in both hemispheres, suggesting a facilitatory role played by the callosal
neurons that enables the asymmetrical epileptogenic
susceptible state of the two hemispheres to develop bisynchronous and
bisymmetrical epileptiform discharges. Significance: Corpus
callosotomy decreased the quantity of the epileptiform discharges, suggesting the transhemispheric
facilitation of seizure mechanisms.
NeuroImage
Volume 19, Issue 3 , July 2003,
Pages 1228-1232
Language lateralization in patients with temporal lobe
epilepsy: a comparison of functional transcranial
Doppler sonography and the Wada test
Susanne Knake,
, a, Anja Haaga, Hajo M. Hamera, Christine Dittmera, Siegfried Bienb,
Wolfgang H. Oertela and Felix Rosenowa
This
study prospectively investigates whether noninvasive functional transcranial Doppler sonography (fTCD) is a useful tool to determine hemispheric language
lateralization in the presurgical evaluation of
patients with medically intractable temporal lobe epilepsy (TLE). fTCD results were compared with
the Wada test as the gold standard. Wada test and fTCD
were performed in 13 patients suffering from TLE. fTCD continuously measured blood flow velocities in
both middle cerebral arteries, while the patient was performing a cued word
generation task. During the Wada test, spontaneous speech, comprehension,
reading, naming, and repetition were investigated. A laterality index (LI) was
obtained by both procedures. Due to a lack of an acoustic temporal bone window,
fTCD could not be performed in two patients (15%). In
9 of the remaining 11 patients hemispheric language dominance was found on the
left side, in 1 patient on the right side, and 1 patient showed bihemispheric language representation. In all patients fTCD and the Wada test were in good agreement regarding
hemispheric language lateralization, and the LI of both techniques were highly
correlated (r = 0.776, P = 0.005). fTCD
gives predictions of hemispheric language dominance consistent with the Wada
test results even in children, patients with low IQ, and nonnative speakers. It
is an alternative to the Wada test in determining language lateralization in patients
with temporal lobe epilepsy.
Barkley, Gregory L. *+; Baumgartner, Christoph
++
MEG and EEG in Epilepsy.[Review]
Journal of Clinical Neurophysiology.
20(3):163-178, May/June 2003.
Summary:
Both EEG and magnetoencephalogram (MEG), with a time
resolution of 1 ms or less, provide unique neurophysiologic data not obtainable
by other neuroimaging techniques. MEG has now emerged
as a mature clinical technology. While both EEG and MEG can be performed with
more than 100 channels, MEG recordings with 100 to 300 channels are more easily
done because of the time needed to apply a large number of EEG electrodes. EEG
has the advantage of the long-term video EEG recordings, which facilitates
extensive temporal sampling across all periods of the sleep/wake cycle. MEG and
EEG seem to complement each other for the detection of interictal
epileptiform discharges, because some spikes can be
recorded only on MEG but not on EEG and vice versa. Most studies indicate that
MEG seems to be more sensitive for neocortical spike sources. Both EEG and MEG
source localizations show excellent agreement with invasive electrical
recordings, clarify the spatial relationship between the irritative
zone and structural lesions, and finally, attribute epileptic activity to lobar
subcompartments in temporal lobe and to a lesser
extent in extratemporal epilepsies. In temporal lobe
epilepsy, EEG and MEG can differentiate between patients with mesial, lateral, and diffuse seizure onsets. MEG
selectively detects tangential sources. EEG measures both radial and tangential
activity, although the radial components dominate the EEG signals at the scalp.
Thus, while EEG provides more comprehensive information, it is more complicated
to model due to considerable influences of the shape and conductivity of the
volume conductor. Dipole localization techniques favor MEG due to the higher
accuracy of MEG source localization compared to EEG when using the standard
spherical head shape model. However, if special care is taken to address the
above issues and enhance the EEG, the localization accuracy of EEG and MEG
actually are comparable, although these surface EEG analytic techniques are not
typically approved for clinical use in the
Epilepsia
Volume 44 Issue s7 Page 26 - September 2003
Assessing the Efficacy of Antiepileptic Treatments: The
Ketogenic Diet
Elizabeth A. Thiele
Summary: Purpose: To evaluate the evidence for
determining if the ketogenic diet is an effective
treatment for epilepsy. Methods: A
literature review of published data over the past 80 years concerning the ketogenic diet was performed, focusing on efficacy,
Journal of Clinical Psychology
Volume 59, Issue 9 , Pages 933 -
942
Minimal model to document psychometric change after
standard anterior temporal lobectomy for intractable
seizure disorder
Raymond M. Costello *, Bruce Mayes, C. Akos
Szabo, Dennis G. Vollmer
University of
*Correspondence to Raymond M. Costello, University of
Texas Health Science Center at San Antonio, Mail Code 7792, 7703 Floyd Curl
Drive, San Antonio, TX 78229-3900; e-mail: costello@uthscsa.edu
Neuropsychological
assessment of persons with epilepsy is recommended whenever neurosurgery is
considered as an alternative therapy for seizure disorders refractory to
ordinary medical management. Although psychological assessment is common in
centers specialized in the care of epilepsy patients, standardized protocols
are not common. This study addresses the question of the optimal minimal test
battery necessary to differentiate groups of right-handed patients with
refractory, complex partial seizure disorder who receive either right or left
anterior temporal lobectomy or no surgery. No
variable differentiated the groups before surgery. Only Logical
Memory-Immediate of the Wechsler Memory Scale differentiated the groups
following surgery. This finding is consistent with the literature.
Mayo Clin Proc. 2003 Jun;78(6):781-7.
Neuropsychiatric and memory issues in epilepsy.
Bortz JJ.
Department of Psychiatry and Psychology,
Mayo Clinic,
Epilepsy
is an extremely complex disorder characterized by marked variability in
clinical presentation, etiology, diagnostic certainty, and therapeutic options.
Neuropsychiatric and cognitive concomitant disorders
are equally diverse and complex. Depression and anxiety, for example, may be
preexisting conditions, occur only in peri-ictal or ictal states, or persist as constant interictal
phenomena; both place additional burden on memory functions, which are further
taxed by the effects of recurrent seizures, temporal lobe insult, and antiseizure medications. Such factors present considerable
clinical challenges, particularly in outpatient settings. This article provides
an overview of major psychiatric features of epilepsy and of issues regarding
the nature of memory deficits in this neurologic
population. The importance of identifying and treating potentially reversible
causes of memory impairment and related forms of cognitive impairment is
emphasized.
Neurosurg Rev. 2003 Aug 22 [Epub ahead of print].
Advances in neuroimaging:
management of partial epileptic syndromes.
Schauble B, Cascino
GD.
Division of Epilepsy, Department of Neurology, Mayo Clinic
Foundation, 200 First Street SW, Rochester, MN 55905, USA.
Structural
and functional neuroimaging studies are essential in
the evaluation of individuals with partial epilepsy syndromes. Magnetic
resonance imaging (MRI) is important to delineate structural abnormalities
underlying seizure disorders, commonly including hippocampal
sclerosis or cortical dysplasias. Identification of a
structural lesion is often a reliable indicator of the site of seizure onset.
Magnetic resonance spectroscopy (MRS) allows us to investigate cerebral
metabolites and some neurotransmitters. Reduction in various metabolite
concentrations has proven to be prognostically
valuable when no structural abnormality is identified. Positron emission
tomography (PET) using deoxyglucose demonstrates
areas of reduced glucose metabolism, which are the hallmark of epileptogenic zones and usually extend beyond the
underlying anatomical region. It is useful in temporal lobe epilepsy for
lateralization; however, results in extratemporal
lobe epilepsy have been less favorable. More promising is the use of
benzodiazepine receptor ligands, which are reduced in
the epileptogenic zone in a more restricted
distribution. This appears to be helpful in the localization of extratemporal seizure foci. Peri-ictal
single photon emission computed tomography measures increased blood flow during
the ictal event and is beneficial in patients with
normal MRI studies to determine lateralization and localization of the ictal onset zone. All imaging modalities should be
correlated with clinical and neurophysiological data.
Journal of the Neurological Sciences Volume 213, Issues
1-2, Pages
77-82
Complex partial status epilepticus
associated with anti-Hu paraneoplastic
syndrome
Dina A. Jacobs, Kar-Ming Fung, Noah M. Cook, William W. Schalepfer,
Herbert I. Goldberg and Mark M. Stecker
Although
seizures can be a manifestation of paraneoplastic
disorders, there are few descriptions of the association between the anti-Hu paraneoplastic syndrome and epilepsia partialis continua. A
new case of refractory complex partial status epilepticus
in a patient with a paraneoplastic syndrome
associated with a poorly differentiated mediastinal
tumor that expressed Hu antigen is described
clinically, pathologically, and electrographically. We discuss the presentation
of focal seizures in a disease that is characterized by diffuse pathologic
involvement of the brain. The progression of EEG, MRI, and clinical findings
during the course of the illness is also discussed. To our knowledge, this is
the first description of paraneoplastic epilepsia partialis continua
associated with diffuse pathologic abnormalities.
Epilepsia
Volume 44 Issue 9 Page 1241 - September 2003
Increased Frequency of Rolandic
Spikes in ADHD Children
Martin Holtmann, Katja Becker, Beate Kentner-Figura, and Martin H. Schmidt
Summary:
Purpose: Some children with rolandic epilepsy have
associated neuropsychiatric deficits resembling
symptoms of attention deficit-hyperactivity disorder (ADHD), the most common
neurobehavioral disorder of childhood. The clinical overlap between both
syndromes has received relatively little attention. The study examines the
frequency of rolandic spikes in nonepileptic
children with ADHD and compares it with a historic control group of 3,726
normal school-aged children. ADHD patients with and without discharges are
compared regarding age at admission, sex, global functioning, and distribution
of ADHD subtypes. Methods: The EEGs of 483 ADHD outpatients between 2 and 16
years meeting diagnostic criteria for ADHD according to Diagnostic and
Statistical Manual of Mental Disorders (DSM-IV) were evaluated prospectively.
If rolandic spikes were present, separate sleep EEGs
were performed to exclude a bioelectrical status epilepticus
during slow-wave sleep. Results: Rolandic spikes were
detected in the EEGs of 27 children (5.6%; 22 boys and five girls). Seizure
rate during follow-up tended to be larger in children with rolandic
spikes. No significant differences were found between ADHD patients with and
without spikes regarding sex and global functioning. ADHD children with rolandic spikes came to our attention significantly earlier
than did children without discharges and tended to exhibit more
hyperactive-impulsive symptoms, evidenced in a larger proportion of the
diagnosis of ADHD combined type than ADHD inattentive type. Conclusions: The
frequency of rolandic spikes in children with ADHD is
significantly higher than expected from epidemiologic studies. The question
arises how ADHD symptoms are related to rolandic
spikes in this ADHD subgroup. Possibly rolandic
discharges or underlying, not fully understood mechanisms of epileptogenesis decrease the vulnerability threshold,
advance the onset, or aggravate the course of ADHD.
Epilepsia
Volume 44 Issue 8 Page 1122 - August 2003
Confirmation of Nonconvulsive
Limbic Status Epilepticus with the Sodium Amytal Test
*Jorge G. Burneo, *
Summary: Is it a seizure? This question can be
difficult for a clinician to answer, and it may be more critical if the
possible seizure lasts >30 min. Long-duration questionable seizure activity
changes the question to, "Is it status epilepticus?"
Status epilepticus (SE) can be divided into
convulsive and nonconvulsive types. Convulsive SE is
the most easily recognized, whereas nonconvulsive SE
is more clinically variable and controversial. The term nonconvulsive
SE is more often applied to patients who are severely obtunded or comatose with
minimal or no motor movements, or in a stupor of altered consciousness reflecting
generalized ictal activity. Nonconvulsive
SE also can be caused by focal seizure activity, sometimes restricted to deep
small volumes of brain in which scalp EEG may not be diagnostic. We present
the case of a patient who had dominant limbic hippocampal
SE, but in whom the diagnosis could not be confirmed until a modified novel use
of the sodium amytal test was performed.
Journal of the Neurological Sciences Volume 213, Issues
1-2, Pages
83-86
Bilateral frontal polymicrogyria
and epilepsy in a patient with Turner mosaicism: a
case report
M. Tombini, M. G. Marciani, A. Romigi, F. Izzi, F. Sperli, A. Bozzao, R. Floris, R. De Simone
and F. Placidi
Turner's
syndrome (TS) is rarely associated with serious abnormalities of brain
structure or malformations of cortical development. We report a 17-year-old
girl with TS and 45,XO/46,XX mosaicism
presenting bilateral frontal polymicrogyria (BFP) and
epilepsy. To our knowledge, the association between TS and BFP has never been
reported to date. Our observation confirms that in humans the X-chromosome
plays an important role in the development and specialization of brain
structure and function. We hypothesize that the absence or abnormalities of
developmental genes localized on the X-chromosome could be involved in the
pathogenesis of BFP observed in our patient.
Seizure. 2003 Oct;12(7):519-521.
Caffeinated beverages and decreased seizure control.
KAUFMAN KR, SACHDEO RC.
Department of Psychiatry, UMDNJ-
Seizure
control is often affected by seizure threshold lowering behaviours.
In this case report, the authors address excessive caffeine ingestion from tea
with increased seizure frequency. When decaffeinated beverages were substituted
for the tea, seizure frequency returned to baseline. Similar findings occurred
when the patient was re-challenged. The authors recommend avoidance of
excessive caffeine in patients with epilepsy.
Seizure. 2003 Oct;12(7):448-455.
Magnetoencephalographic analysis of bilaterally synchronous discharges in benign rolandic epilepsy of childhood.
LIN YY, CHANG KP, HSIEH JC, YEH TC, Yu HY, KWAN SY, YEN
DJ, YIU CH, HARI R.
The
purpose of this study was to examine the spatial and temporal relationship
between bilateral foci of bilaterally synchronous discharges in benign rolandic epilepsy of childhood (BREC) using a whole-scalp neuromagnetometer. We simultaneously recorded interictal magnetoencephalographic
(MEG) and electroencephalographic (EEG) signals in six children with BREC. Interictal spikes were classified into three groups:
bilaterally synchronous discharges (BSDs), unilateral
discharges on right side (UD-R), and unilateral discharges on left side (UD-L).
We used equivalent current dipole (ECD) modelling to analyse the cortical sources of interictal
spikes. Both BSDs and UDs
were found in Patients 1-4, whereas only UDs were
identified in Patients 5 and 6. The ECDs of interictal spikes were located in rolandic
regions, 10-20mm anterior and lateral to hand somatosensory
cortices. Multi-dipole analysis of BSDs showed two ECDs in homotopic motor areas of
the hemispheres. During BSDs, the right-sided
activation preceded the left-sided activation by 15-21milliseconds in Patients
1 and 2. In Patients 3 and 4, the activation occurred 17-20milliseconds earlier
in the left than the right hemisphere. Within the same hemisphere, the sources
of BSDs and UDs were
located in similar areas. In conclusion, our results imply the cortical epileptogenicity in bilateral perirolandic
areas in BREC. The sequential activation during BSDs
in both hemispheres suggest the existence of synaptic
connections, possibly via the corpus callosum,
between bilateral irritative foci.
Seizure. 2003 Oct;12(7):502-507.
Understanding the information needs
of women with epilepsy at different lifestages:
results of the 'Ideal World' survey.
CRAWFORD P, HUDSON S.
Department of Neurosciences,
The
impact of some commonly prescribed anti-epilepsy drugs (AEDs)
on female health is well documented. Yet many women continue to experience side
effects such as menstrual irregularities, interactions with hormonal
contraception/HRT and teratogenicity [Seizure 8
(1999) 201] through lack of awareness or opportunity to discuss problems with a
health professional on a regular basis.The 'Ideal
World' survey aimed to:assess quality of current
treatment information provision to women with epilepsy at different life stages
(childbearing age, pre-conception/pregnancy, menopause);identify information
needs and wants with a view to ensuring that all women with epilepsy are counselled appropriately, in a timely manner and able to
make informed choices about their treatment.The
survey content was developed with a steering group of epilepsy specialists
during 2001 (see 'ACKNOWLEDGEMENTS') and mailed to Epilepsy Action (formerly
the British Epilepsy Association) UK female membership aged 19+ (approximately
12000) during the period of January 2002. A sample of 2000 randomly selected
responses was analysed by the Planning Shop International.The survey shows that women are not receiving
important information about their condition and possible adverse effects of
treatment, which could have profound implications for their health and the
health of their unborn child. One third (33%) of women of childbearing age were
not considering having children because of their epilepsy.Women
with epilepsy need regular review and should receive appropriate information about
the impact of their treatment in a timely manner.
Epilepsia
Volume 44 Issue s10 Page 27 - October 2003
Prevention of Epilepsy After Head Trauma: Do We Need
New Drugs or a New Approach?
Larry S. Benardo:
lbenardo@downstate.edu
Summary:
Annually in the
Kim, Hongkeun; Yi, Sangdoe ;
Son, Eun Ik ; Kim, Jieun
Differential Effects of Left Versus
Right Mesial Temporal Lobe Epilepsy on Wechsler
Intelligence Factors.
This
study investigates the effects of left versus right mesial
temporal lobe epilepsy (MTLE) on Wechsler intelligence factors. In the left
MTLE group, the Verbal Comprehension (VC) factor score was significantly lower
than the Perceptual Organization (PO) factor score,
whereas in the right MTLE group, the
Epilepsia Volume 44 Issue s10
Page
Epidemiology of Posttraumatic Epilepsy: A Critical
Review
Lauren C. Frey; laurencfrey@hotmail.com
Summary:
Problem: Traumatic brain injury (TBI) is a major cause of epilepsy. We need to
understand its frequency and its contribution to the total spectrum of the
convulsive disorders.
Methods: A review of selected articles dealing with
epilepsy after brain trauma was undertaken.
Results: The number of epidemiologic studies of
posttraumatic seizures has increased substantially over the past 40-50 years,
offering steadily increasing knowledge of the frequency, natural history, and
risk factors of this well-recognized complication of TBI. In general, the
incidence of posttraumatic seizures varies with the time period after injury
and population age range under study, as well as the spectrum of severity of
the inciting injuries, and has been reported to be anywhere from 4 to 53%. As high as 86% of patients with one seizure after TBI will have a
second in the next 2 years. Longer-term remission rates of 25-40% have
been reported. Significant risk factors for the development of seizures in the
first week after injury include acute intracerebral hematoma (especially subdural hematoma), younger age, increased injury severity, and
chronic alcoholism. Significant risk factors for the development of seizures
>1 week after TBI include seizures within the first week, acute
intra-cerebral hematoma (especially subdural hematoma), brain
contusion, increased injury severity, and age >65 years at the time of
injury.
Conclusions: Epilepsy is a frequent consequence of brain
injury in both civilian and military populations. We understand some factors
associated with its development, but there remain many unanswered questions.
Epilepsia Volume 44 Issue s10 Page
Risk Factors for Posttraumatic Seizures in Adults
Nancy R. Temkin;
temkin@u.washington.edu
Summary:
Purpose: Traumatic brain injury has long been known to be a cause of epilepsy.
Most information on risk factors for developing posttraumatic seizures is from
before computed tomography (CT) scanning became universal. This article looks
at factors about the injury or individual that put people at especially high
risk of developing posttraumatic seizures.
Methods: We considered 783 cases at high risk of
developing seizures, followed up for 2 years as part of seizure prophylaxis
studies. Cumulative incidence of seizures in subgroups and standardized
incidence ratios were used to identify factors related to unprovoked seizure
risk.
Results: Subgroups with significantly elevated risk
include those with evacuation of a subdural hematoma; surgery for an intracerebral
hematoma; Glasgow Coma Scale in the severe range of 3
to 8; early seizures, especially delayed early seizures; time to following
commands of a week or more; depressed skull fracture that was not surgically
elevated; dural penetration by injury; at least one nonreactive pupil; and parietal lesions on CT scan.
Conclusions: Both the risk factors and the time course of
the risk are important for designing seizure-prophylaxis studies and, if an
effective prophylactic regimen is identified, for deciding on appropriate
candidates for prophylaxis.
Epilepsia Volume 44 Issue s10
Page
doi:10.1046/j.1528-1157.44.s10.1.x
Overview of Studies to Prevent Posttraumatic Epilepsy
Ettore Beghi;
beghi@marionegri.it
Summary:
Purpose: Prevention of posttraumatic epilepsy (PTE) is of primary importance to
reduce the degree of functional morbidity following traumatic brain injury
(TBI). However, the effects of antiepileptic drugs (AEDs)
in patients with TBI must be assessed separately in terms of prevention and
control of provoked seizures (which include immediate and early posttraumatic
seizures) and prevention of subsequent unprovoked seizures (late posttraumatic
seizures or PTE).
Methods: Potential mechanisms for prevention of epileptogenesis as well as reports and systematic reviews
were evaluated to determine strategies and results of attempts to reduce or
prevent the development of epilepsy following TBI.
Results: In observational studies, after a period ranging
from 6 months to 13 years, the proportion of cases developing seizures was
0-10% in patients receiving treatment compared to 2-50% in those who were left
untreated. In randomized clinical trials, the difference between active
treatment [phenytoin (PHT), phenobarbital,
or carbamazepine (CBZ)] and placebo was less
remarkable after a follow-up ranging from
Conclusions: The failure to influence the risk of PTE in
studies of patients with TBI are similar to findings of meta-analysis of
randomized clinical trials on seizure prevention in other conditions, such as
febrile seizures, cerebral malaria, craniotomy, and excessive alcohol intake. For
these reasons, the prophylactic use of AEDs should be
short-lasting and limited to the prevention of immediate and early seizures.
Chronic treatment should be considered only after a diagnosis of PTE.
Annual Review of Neuroscience
Jul 2003, Vol. 26, pp. 599-625
THE BIOLOGY OF EPILEPSY GENES
Jeffrey L. NoebelsDepartment of
Neurology, Baylor Coll of Med: jnoebels@bcm.tmc.edu
Mutations
in over 70 genes now define biological pathways leading to epilepsy, an
episodic dysrhythmia of the cerebral cortex marked by
abnormal network synchronization. Some of the inherited errors destabilize
neuronal signaling by inflicting primary disorders of membrane excitability and
synaptic transmission, whereas others do so indirectly by perturbing critical
control points that balance the developmental assembly of inhibitory and
excitatory circuits. The genetic diversity is now sufficient to discern short-
and long-range functional convergence of epileptogenic
molecular pathways, reducing the broad spectrum of primary molecular defects to
a few common processes regulating cortical synchronization. Synaptic inhibition
appears to be the most frequent target; however, each gene mutation retains
unique phenotypic features. This review selects exemplary members of several
gene families to illustrate principal categories of the disease and trace the
biological pathways to epileptogenesis in the
developing brain.
Epilepsia, Volume 44 Issue s10
Page
The Epidemiology of Traumatic Brain Injury: A Review
John Bruns, Jr., and W. Allen
Hauser; wahauser@optonline.net
Summary:
Purpose: Traumatic brain injury (TBI) not only has considerable morbidity and
mortality, but it is a major cause of epilepsy. We wish to determine the
frequency of TBI, special groups at risk for TBI, and mortality from TBI.
Methods: We reviewed studies of TBI that are either
population based or derived from definable catchment
areas that allow determination of incidence, identification of risk groups, and
mortality. We review methodology used in epidemiologic studies of TBI and try
to distinguish this data from that of head injury not necessarily affecting the
brain. We report epidemiologic characteristics of TBI, including incidence,
differences by age, gender, race and ethnic group, and geographic variation,
and mortality.
Results: Population-based studies in the
Conclusions: TBI is a major public health problem as well
as a major cause of epilepsy. If primary prevention is to be undertaken, we
must understand the epidemiology of the condition. The primary causes of TBI
vary by age, socioeconomic factors, and geographic region, so any planned
interventions must be tailored accordingly.
Nature Neuroscience
October 2003 Volume 6 Number 10 pp 1079 - 1085
In vitro formation of a secondary epileptogenic
mirror focus by interhippocampal propagation of
seizures
Ilgam Khalilov,
Gregory L Holmes & Yehezkel Ben-Ari; ben-ari@inmed.univ-mrs.fr
We have
determined whether seizures generate an epileptogenic
focus in distal structures using an in vitro preparation composed of three
independent chambers that accommodate two intact hippocampi
and their connecting commissures. This enabled us to
apply a convulsive agent to one hippocampus, allow the propagation of a given
number of seizures to the other side and block the connections reversibly by
applying tetrodotoxin (TTX) to the commissural
chamber. The propagation of seizures from the kainate-treated
side to the naive side transformed the latter into an independent epileptogenic focus that was capable of generating
spontaneous and evoked seizures. The induction mechanism required activation of
NMDA receptors and the epileptogenic transformation
was associated with long-term alterations in GABAergic
synapses, which became excitatory because of a shift in the chloride reversal
potential, ECl. These
data indicate that the excitatory actions of GABA may be a fundamental property
of epileptogenic structures.
Journal of Neurology, Neurosurgery and Psychiatry, Sept
2003 v74 i9 p1240(5)
Contralateral medial
temporal lobe damage in right but not left temporal lobe epilepsy: a [sup.1]H magnetic resonance spectroscopy study.
F Zubler; M Seeck; T Landis; F Henry; F Lazeyras.
Background:
Proton magnetic resonance spectroscopy (MRS) of the hippocampus is useful in lateralising the epileptic focus in temporal lobe epilepsy
for subsequent surgical resection. Previous studies have reported abnormal contralateral MRS values in up to 50% of the patients. Objective: To identify the contributing
factors to contralateral damage, as determined by
MRS, and its extension in patients with temporal lobe epilepsy. Methods: Single voxel
MRS was carried out in the hippocampus and lateral temporal neocortex
of both hemispheres in 13 patients with left temporal lobe epilepsy (LTLE) and
16 patients with right temporal lobe epilepsy (RTLE). All patients had mesial temporal lobe epilepsy with hippocampal
sclerosis. Controls were 21 healthy volunteers of comparable age. Results: Consistent with previous studies,
the NAA/(Cho+Cr) ratio was
abnormally low in the hippocampus ipsilateral to the
focus (p < 0.0001), and there were lower values in both patient groups in
the ipsilateral temporal neocortex
(p < 0.0001). Patients with RTLE had left hippocampal
MRS anomalies (p = 0.0018), whereas the right hippocampus seemed to be
undamaged in LTLE patients. Conclusions: Unilateral mesial
temporal lobe epilepsy is associated with widespread metabolic abnormalities
which involve contralateral mesial
and neocortical temporal lobe structures. These abnormalities appear to be more
pronounced in patients with RTLE.
Journal of Neurology, Neurosurgery and Psychiatry, Sept
2003 v74 i9 p1245(5)
Amygdala volumetry in
"imaging-negative" temporal lobe epilepsy.
SPC Bower; SJ Vogrin; K Morris;
I Cox; M Murphy; CJ Kilpatrick; MJ Cook.
Objective:
Although amygdala abnormalities are sometimes
suspected in "imaging-negative" patients with video EEG confirmed
unilateral focal epilepsy suggestive of temporal lobe epilepsy (TLE), amygdala asymmetry is difficult to assess visually. This
study examined a group of "imaging-negative" TLE patients, estimating
amygdala volumes, to determine whether cryptic amygdala lesions might be detected. Methods: Review of video EEG monitoring data
yielded 11 patients with EEG lateralised TLE and
normal structural imaging. Amygdala volumes were
estimated in this group, in 77 patients with pathologically verified hippocampal sclerosis (HS), and in 77 controls. Results: Seven of 11
"imaging-negative" cases had both significant amygdala
asymmetry and amygdala enlargement, concordant with
seizure lateralisation. Although significant amygdala asymmetry occurred in 35 of 77 HS patients, it was
never attributable to an abnormally large ipsilateral
amygdala. Compared with patients with HS, patients
with amygdala enlargement were less likely to have
suffered secondarily generalised seizures
(p<0.05), and had an older age of seizure onset (p<0.01). Conclusion: Abnormal amygdala
enlargement is reported in seven cases of "imaging-negative" TLE.
Such abnormalities are not observed in patients with HS. It is postulated that amygdala enlargement may be attributable to a developmental
abnormality or low grade tumour. It is suggested that
amygdala volumetry is
indicated in the investigation and diagnosis of "imaging-negative"
TLE.
Cochrane Database Syst Rev. 2003;4:CD002029.
Psychological treatments for
epilepsy.
Ramaratnam S, Baker G, Goldstein
L.
BACKGROUND:
Psychological interventions such as relaxation therapy, cognitive behaviour therapy, electroencephalogram (EEG) bio-feedback
and educational interventions have been used alone or in combination in the
treatment of epilepsy, to reduce the seizure frequency and improve the quality
of life. OBJECTIVES: To assess whether the treatment of epilepsy with
psychological methods is effective in reducing seizure frequency and/or leads
to a better quality of life. SEARCH STRATEGY: We searched the Cochrane Epilepsy
Group trial register (
J Neuropsychiatry Clin Neurosci 15:450-452, November 2003
Mesial Temporal
Structures and Comorbid Anxiety in Refractory Partial
Epilepsy
Parthasarathy Satishchandra, D.M., Ennapadam S.
Krishnamoorthy, M.D., Ludger
Tebartz van Elst, M.D.,
Louis Lemieux, Ph.D., Mathias Koepp,
Ph.D., Richard J. Brown, Ph.D. and Michael R. Trimble, M.D.;
m.trimble@ion.ucl.ac.uk (E-mail).
We used
quantitative magnetic resonance imaging (MRI) to examine the mesial temporal structures in subjects with refractory
partial epilepsy and comorbid anxiety and found
preservation with a right-sided preponderance. The findings indicate a role for
this brain region in the genesis of anxiety.
We
have shown that the volume of the amygdala and
hippocampus is preserved in subjects with refractory partial epilepsy and
anxiety, in contrast to patients with epilepsy and no associated
psychopathology. This is despite the significantly earlier seizure onset and
longer duration of epilepsy in this group. Our findings are in line with recent
literature linking these structures, the amygdala in
particular, to generalized anxiety disorder11 and subjective anxiety in social
phobia12 and are unlikely therefore to be specific to refractory epilepsy.
Epilepsia. 2004 Jan;45(1):64-70.
Depression and altered quality of life in
women with epilepsy of childbearing age.
Beghi E, Roncolato M, Visona G.
Purpose: To
calculate the prevalence of depression in a referral population of women of
childbearing age, to define the factors associated with depression, and to
assess health-related quality of life (HRQOL) in the same population.
Methods: The 642 consecutive women with epilepsy aged 18-55 years were enrolled
by 40 neurologists over an 8-month period and asked to give details on selected
demographic and clinical features regarding the disease,
any associated clinical condition, and any drug treatment. Depression was
diagnosed by using the
Epilepsy Behav.
2003 Dec;4(6):674-9.
Antidepressive
treatment in patients with temporal lobe epilepsy and major depression: a
prospective study with three different antidepressants.
Kuhn KU, Quednow BB, Thiel M, Falkai P, Maier W, Elger CE.
Major
depression (MD) is underdiagnosed and undertreated in patients with temporal lobe epilepsy (TLE).
Side effects of some antidepressants, like increased risk of seizures and
drug-drug interactions with anticonvulsants, contribute to undertreatment
of MD in patients with TLE. We analyzed post hoc the data from 2 years of
treatment of inpatients with MD and TLE. Seventy-five patients received
standard treatment with citalopram, mirtazapine, or reboxetine,
respectively, at recommended dosage. Examinations were done with the Hamilton
Rating Scale for Depression at admission and after 4 and 20-30 weeks. Plasma
levels of anticonvulsants were examined at admission and discharge. Seizures
were documented. The antidepressive treatment was
efficacious in all antidepressant groups. No case of serious adverse event or
drug interaction occurred. There was no increase in frequency or severity of
seizures. At endpoint the dropout rate for mirtazapine
was significantly higher than that for reboxetine or citalopram. Reboxetine showed a
trend to be more efficacious than citalopram but not mirtazapine at Week 4.
Confirmatory Factor Analysis of the
James H. Baños, David L. Roth,
Cheryl Palmer, Richard Morawetz,
Latent
constructs involved in California Verbal Learning Test (D. C. Delis, J. H.
Kramer, E. Kaplan, & B. A. Ober, 1987)
performance were examined using confirmatory factor analysis in 388 epilepsy
surgery candidates. Eight factor models were compared. A single-factor model
was examined, along with 7 models accommodating constructs of auditory
attention, inaccurate recall, and delayed recall in different combinations. The
retained model consisted of 3 correlated factors: Auditory Attention, Verbal
Learning, and Inaccurate Recall. Validity of this factor structure was examined
in a subsample of patients with left and right
temporal lobe epilepsy. All 3 factors were related to seizure focus and
magnetic resonance imaging hippocampal volume. Only
Verbal Learning was related to hippocampal
neuropathology, supporting the distinction between learning and attention in
the factor structure.
Lateralization of Epileptic Foci by Neuropsychological Testingin Mesial Temporal Lobe
Epilepsy
Hongkeun Kim, Sangdoe Yi and Eun Ik Son, Jieun Kim
This
study investigated the lateralizing value of neuropsychological testing in presurgical evaluation of mesial
temporal lobe epilepsy (MTLE). This study differed from previous ones in that
the cutoff values were determined to yield high positive predictive values (PPVs), multiple neuropsychological predictors were
considered in combination, and patients with atypical language dominance or low
intelligence were not excluded from the sample. The participants were 92
patients with MTLE (left, n = 47; right, n = 45) who showed good postoperative
seizure control. With a stringent cutoff criterion, the multiple
neuropsychological predictors considered in combination yielded a sensitivity
of 15% and a PPV of 93%, and with a less stringent cutoff criterion, a
sensitivity of 37% and a PPV of 83%.
A
systematic review of the contribution of qualitative research to the study of
quality of life in children and adolescents with epilepsy.
Mcewan,
KJ,
Seizure.
2004 Jan;13(1):3-14.
A sizeable literature focusing on QOL in children and
adolescents with epilepsy has been produced over the last few years. However,
relatively little emphasis has been placed on defining these issues from direct
exploration of children's and adolescents' views. Qualitative methodologies are
proposed in this review as an appropriate means of eliciting such information.This review systematically investigated the
extent to which studies of QOL in children and adolescents with epilepsy have
used recognised qualitative methodology. Articles for
inclusion were identified by searching the term 'epilepsy', combined with
'adolescent(s) and/or child(ren)'
and 'psychosocial and/or quality of life'. Selected articles were reviewed and
rated using CASP Guidelines for qualitative research by two independent raters.Seventeen studies were retrieved through literature
search. Of these six used some form of qualitative methodology either
individually or combined with quantitative methods. However, only one study met
quality criteria for selection in this systematic review.A
summary of both selected and excluded studies is presented and methodological
limitations discussed. Recommendations for appropriate methodology for
investigation of QOL issues in children and adolescents are given
***Non-Epiletic Seizures (NES), including Psychogenic Seizures
…many
more coming…
Salmon, Peter DPhil; Al-Marzooqi, Suad M. PhD; Baker, Gus
PhD; Reilly, James PhD
Childhood Family Dysfunction and Associated Abuse in
Patients With Nonepileptic Seizures: Towards a Causal
Model.[Article]
Psychosomatic Medicine.
65(4):695-700, July/August 2003.
Objective:
A history of childhood sexual abuse is thought to characterize patients with nonepileptic seizures (NES). We tested the hypotheses: 1)
that history of sexual abuse is more prevalent in patients with NES than in
controls with epilepsy; 2) that such abuse is associated with NES, not directly
but because it is a marker of family dysfunction; and 3) that family
dysfunction and abuse are, in turn, linked to NES because they increase a
general tendency to somatize. Methods: We compared 81
patients with NES with 81 case-matched epilepsy patients, using questionnaires
to elicit recollections of sexual, physical, and psychological abuse and family
atmosphere and to quantify current somatization.
Results: Although each form of abuse was more prevalent in NES patients, only
child psychological abuse uniquely distinguished NES from epilepsy. However,
its association with NES was explained by family dysfunction. A general tendency to somatize
explained part of the relationship of abuse to NES. Conclusions:
Abuse therefore seems to be a marker for aspects of family dysfunction that are
associated with - and may therefore cause - somatization
and, specifically, NES.
(***Problem: NES assumed homogenous, psychogenic, when
it is not – hence, sample is diluted)