Masaki Iwasaki - Profile on Academia.edu (original) (raw)
Papers by Masaki Iwasaki
手術で治癒したてんかん患者における術前脳磁図(MEG)スパイクの局在
Paired‐Pulse Stimulationを用いた局所CCEPによるてんかん皮質興奮性の検討
Initial delta and delayed theta/alpha pattern in the temporal region on ictal EEG suggests purely hippocampal epileptogenicity in patients with mesial temporal lobe epilepsy
Clinical Neurophysiology
OBJECTIVE To determine whether the ictal scalp EEG findings suggest purely hippocampal epileptoge... more OBJECTIVE To determine whether the ictal scalp EEG findings suggest purely hippocampal epileptogenicity in patients with mesial temporal lobe epilepsy (mTLE) associated with hippocampal sclerosis (HS). METHODS Twenty-three patients with mTLE with pathologically confirmed HS were divided into 12 with epileptogenicity only in the hippocampus (HS only group) and 11 with epileptogenicity in both the hippocampus and temporal neocortex or other locations (HS plus group), based on the combination of surgical procedures, postoperative outcome, and pathological findings. Sixteen underwent selective amygdalohippocampectomy (SelAH) and 7 received anterior temporal lobectomy. Ictal scalp EEG findings of 79 focal impaired awareness seizures were compared between the HS only and HS plus groups. We focused on the 1-4 Hz rhythmic delta activity at ictal onset followed by 5-9 Hz rhythmic theta/alpha activity 10-30 s after the onset in the temporal region. RESULTS The initial delta and delayed theta/alpha (ID-DT) pattern was observed in 8 of 12 patients in the HS only group, but in none of 11 patients in the HS plus group (p < 0.01). CONCLUSIONS ID-DT pattern on ictal EEG suggests purely hippocampal epileptogenicity in mTLE with HS. SIGNIFICANCE Patients with the ID-DT pattern are likely to become seizure-free after SelAH.
Neuromagnetic localization of spike discharges correlates with postoperative seizure outcome
Japanese Journal of Neurosurgery, 2000
Optogenetic stimulus-triggered acquisition of seizure resistance
Neurobiology of Disease, 2022
Unlike an electrical circuit, the hardware of the brain is susceptible to change. Repeated electr... more Unlike an electrical circuit, the hardware of the brain is susceptible to change. Repeated electrical brain stimulation mimics epileptogenesis. After such "kindling" process, a moderate stimulus would become sufficient in triggering a severe seizure. Here, we report that optogenetic neuronal stimulation can also convert the rat brain to a hyperexcitable state. However, continued stimulation once again converted the brain to a state that was strongly resistant to seizure induction. Histochemical examinations showed that moderate astrocyte activation was coincident with resilience acquisition. Administration of an adenosine A1 receptor antagonist instantly reverted the brain back to a hyperexcitable state, suggesting that hyperexcitability was suppressed by adenosine. Furthermore, an increase in basal adenosine was confirmed using in vivo microdialysis. Daily neuron-to-astrocyte signaling likely prompted a homeostatic increase in the endogenous actions of adenosine. Our data suggest that a certain stimulation paradigm could convert the brain circuit resilient to epilepsy without exogenous drug administration.
[Ictal Speech Manifesting as Sleep Talking: A Case Report]
Brain and nerve = Shinkei kenkyu no shinpo, 2017
We present a 28-year-old female patient whose epilepsy started at the age of 19. MRI showed right... more We present a 28-year-old female patient whose epilepsy started at the age of 19. MRI showed right perisylvian polymicrogyria. She exhibited various seizure symptoms, such as somatosensory aura involving the left leg, dyscognitive seizures, and amnesic seizures. Her mother indicated that the patient sometimes had "sleep talking", which was associated with presence of epileptic seizures of the next day. Long-term video electroencephalography (EEG) revealed that her episodes of "sleep talking" were epileptic events, specifically ictal speech, originating in the right hemisphere. The present case demonstrates the importance of considering "sleep talk" as an epileptic symptom. Careful history taking is fundamental to carry patients with possibly pathological "sleep talk" to the long-term video EEG, which will contribute correct diagnosis and treatment. (Received August 16, 2016; Accepted September 9, 2016; Published February 1, 2017).
Three patients with posterior quadrant epilepsy showing focal ictal EEG onset during NREM sleep, but not during wakefulness
Sleep Medicine, 2015
Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, Jan 19, 2016
To investigate whether seizure lateralization affects sleep macrostructure in patients with left ... more To investigate whether seizure lateralization affects sleep macrostructure in patients with left and right temporal lobe epilepsy (TLE), as rapid eye movement (REM) sleep is shorter in patients with right hemispheric cerebral infarction than with left. We retrospectively analyzed data from 16 patients with TLE (6 men and 10 women aged 34.9 ± 11.4 years) who underwent polysomnography as well as long-term video electroencephalography. Ten patients were diagnosed with left TLE and six patients with right TLE. Sleep stages and respiratory events were scored based on the American Academy of Sleep Medicine criteria. Sleep and respiratory parameters were compared between the patient groups. Percentage of REM stage sleep was significantly (p < 0.05) lower in patients with left TLE (median 8.8 %, interquartile range 5.5-13.8 %) than in patients with right TLE (median 17.0 %, interquartile range 14.1-18.3 %). The other parameters showed no significant differences. Shorter REM sleep in pati...
Epilepsy Research, 2016
Object: The use of T2 relaxometry was investigated to detect non-sclerotic epileptogenic abnormal... more Object: The use of T2 relaxometry was investigated to detect non-sclerotic epileptogenic abnormality of the hippocampus in presurgical evaluation of temporal lobe epilepsy (TLE). Methods: This prospective study included 30 patients who underwent hippocampectomy as part of surgical treatment of refractory TLE. Ten patients had structural epileptogenic lesions in the extra-hippocampal temporal lobe. Twelve patients underwent intracranial electroencephalography (iEEG) study before surgery. Visual assessment of atrophy and increased T2 signal intensity, volumetry, and T2 relaxometry of hippocampus were performed pre-operatively using 3 T magnetic resonance imaging, and compared with the neuropathological findings and iEEG findings. Magnetic resonance imaging of 30 age-and sexmatched healthy controls was used to establish normal values, which were defined as z score within 2. Results: Visual assessment, volumetry, and T2 relaxometry detected hippocampal abnormalities on the surgical side in 16 (53%), 16 (53%), and 26 (87%) patients, respectively. Hippocampal volume loss was always associated with prolonged T2 relaxation time, and supported by histopathological diagnosis of HS in all cases except one. Hippocampal abnormality was detected only by T2 relaxometry in nine patients (30%). Pathological diagnosis of these cases included mild HS in one, microdysgenesis in one, and granule cell pathology in three. Four patients with normal hippocampal volume and T2 relaxation time had no HS or granule cell pathology. Prolonged T2 relaxation time was associated with medial temporal seizure onset in iEEG (p < 0.05). Conclusions: T2 relaxometry improves the detection of non-sclerotic epileptogenic abnormality of the hippocampus.
Surgecal Implications of Neuromagnetic Spike Localization in Temporal Lobe Epilepsy
Epilepsia Journal of the International League Against Epilepsy, Apr 1, 2002
Clinical Neurophysiology, 2015
Introduction. -La dysplasie de trochlée est un des éléments majeurs de l'instabilité fémoropatell... more Introduction. -La dysplasie de trochlée est un des éléments majeurs de l'instabilité fémoropatellaire. Si sa correction par trochléoplastie apparaît logique, le résultat à long terme de cette intervention n'est pas connu et il persiste une incertitude sur l'évolution arthrosique. Aussi, nous avons mené une étude rétrospective d'une série de trochléoplasties de creusement au recul de 15 ans avec pour objectifs : ( ) d'évaluer à long terme les résultats cliniques et le taux radiologique d'arthrose ; (2) de préciser les résultats en fonction du type d'instabilité et du grade de la dysplasie. Hypothèse. -La trochléoplastie de creusement est une intervention efficace sur la stabilisation de l'articulation fémoropatellaire sans augmenter le risque d'arthrose. Patients et méthodes. -Cette étude analyse rétrospectivement 34 trochléoplasties de creusement au moyen de scores cliniques (scores IKS, Lillois, Kujala et Oxford) et leurs résultats radiologiques (stade d'arthrose selon Iwano) au recul moyen de 15 ans (12-19 ans). Une plastie d'Insall était associée systématiquement et une transposition de la tubérosité tibiale antérieure dans 17 cas (7 transpositions préalables). Résultats. -Aucune récidive d'instabilité objective n'a été observée. Six genoux ont été repris par prothèse pour arthrose et un par transposition de la tubérosité tibiale pour douleur et dérobements au recul moyen de 7 ans (2-16). Les scores moyens Lillois, Kujala et IKS passaient respectivement de 53,3 (30-92), 55 (13-75) et 127 (54-184) en préopératoire à 61,5 (25-93), 76 (51-94) et 152,4 (66-200) au recul (p < 0,05) (reprises incluses). Les résultats fonctionnels étaient significativement meilleurs pour les dysplasies avec éperon versus 153 et Kujula 81, versus 76 [51-94] [p < 0,05]). Les patients étaient satisfaits dans 65 % des cas et le score Oxford total moyen étaient de 24,1 points/60 (12-45 points). La douleur était occasionnelle ou nulle dans 53 % des cas. La saillie de la trochlée passait de 4,9 mm (3-9 mm) à -1,2 mm (-7-4 mm). L'arthrose fémoropatellaire, 10 cas en préopératoire mais aucune > Iwano 2, était présente dans 33/34 cas avec 20 cas > Iwano 2 (65 %) au recul. Discussion. -La trochléoplastie de creusement permet la stabilité fémoropatellaire même en cas de dysplasie sévère pour lesquelles elle donne de meilleurs résultats fonctionnels à long terme. En revanche, elle ne prévient pas l'arthrose fémoropatellaire. Elle doit être réservée aux dysplasies sévères avec éperon en l'associant à des gestes de réalignement de l'appareil extenseur. Niveau de preuve. -IV, étude rétrospective de cohorte.
1-A-D-22. Sleep stages affect the occurrence of high frequency oscillations (HFOs) differently between hippocampus and neocortical areas
Clinical Neurophysiology, 2015
This study was aimed to reveal that influence of sleep stages on the occurrence of HFOs was diffe... more This study was aimed to reveal that influence of sleep stages on the occurrence of HFOs was different between anatomical areas. Nine patients underwent extraoperative intracranial EEG monitoring from both hippocampal depth and neocortical subdural electrodes. Interictal HFOs were detected semi-automatically on EEGs taken during different sleep stages. The difference in the occurrence rate of HFOs between NREM3 and REM sleep stages was normalized per patient, and compared between hippocampus and neocortical electrodes. Number of electrodes showing HFOs at higher rate than standard range was compared between sleep stages and anatomical sites. Hippocampal electrodes ( n = 57) showed higher rate of HFOs during NREM3 sleep than neocortical electrodes ( n = 638) ( p p
1-A-D-26. Pre-operative magnetoencephalographic spike localization in patients with surgically-cured epilepsy
Clinical Neurophysiology, 2015
This study investigated the characteristic localization of magnetoencephalographic (MEG) “green” ... more This study investigated the characteristic localization of magnetoencephalographic (MEG) “green” spikes unrelated to epileptogenicity. Preoperative interictal MEG spike localization was compared with surgical resection areas in 17 patients, who achieved complete seizure freedom after withdrawal from antiepileptic medications. No MEG spikes were detected in two patients. In three patients, all MEG spike-areas were resected. Eleven patients had MEG spikes in both resection and other areas. Spike localization remote from resection-area was classified into three types: (1) antero-mesial temporal spikes ( n = 4); (2) contralateral temporal spikes ( n = 3); and (3) posterior temporo-parietal spikes ( n = 5). Both the antero-mesial and contralateral temporal spikes were found only in patients with mesial temporal lobe epilepsy (TLE). The posterior temporo-parietal spikes were found in patients with mesial TLE, as well as other epilepsies. Mesial temporal spikes generated from the hippocampus can propagate to the anterior temporal neocortex and contralateral temporal lobe. Since these temporal neocortical spikes did not reflect epileptogenicity, seizure freedom was achieved after amygdalohippocampectomy. Temporo-parietal spikes found in TLE and other epilepsies can be a “green” MEG spikes. MEG has high sensitivity to activity in the temporo-parietal area, to where spikes propagate easily.
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, Jan 30, 2015
We hypothesized that high frequency oscillations (HFOs) are differently suppressed during rapid e... more We hypothesized that high frequency oscillations (HFOs) are differently suppressed during rapid eye movement sleep (REM) between epileptogenic and less epileptogenic cortices, and that the suppressive effect can serve as a specific marker of epileptogenicity. Intracranial electroencephalography (EEG) was recorded in 13 patients with drug-resistant epilepsy. HFOs between 80 and 200Hz were semi-automatically detected from total 15-min EEG epochs each for REM and slow wave sleep (SWS). z-Score of HFO occurrence rate was calculated from the baseline rate derived from non-epileptogenic cortex. Intracranial electrodes were labeled as REM dominant HFO (RdH) if REM z-score was greater than SWS z-score or as SWS dominant HFO (SdH) if SWS z-score was greater than REM z-score. Relationship of electrode location to the area of surgical resection was compared between RdH and SdH electrodes. Out of 1070 electrodes, 101 were defined as RdH electrodes and 115 as SdH electrodes. RdH electrodes were ...
Occult dual pathology in mesial temporal lobe epilepsy
Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, Jan 30, 2015
Keywords Dual pathology ´Temporal lobe epilepsy Ganglioglioma Negative magnetic resonance imaging... more Keywords Dual pathology ´Temporal lobe epilepsy Ganglioglioma Negative magnetic resonance imagingDear Sir,Hippocampal sclerosis (HS) can appear secondary to neo-cortical epileptogenic lesion in medically refractoryepilepsy, called dual pathology. In the dual pathology, re-moval of both the primary lesion and HS is necessary toachieve better seizure outcome. However, if the primarylesion is not apparent in pre-operative imaging studies,selective surgery to hippocampus may be performed andfollowed by inadequate seizure control. Here, we report acase of dual pathology which was not diagnosed pre-operatively.A 50-year-old man with drug-resistant temporal lobeepilepsy (TLE) was referred to our department forevaluation of surgical treatment. Seizures had started atage 10 years and had become intractable to multiplemedications at age 22 years. He had aura of fear or deja`-vu followed by complex partial seizures 2–3 times amonth despite antiepileptic medications including carba-mazepine and lamotrigine. Previously, he was treatedwith valproic acid, levetiracetam and zonisamide. Com-prehensive presurgical evaluation including video-elec-troencephalography (EEG), ‘‘epilepsy protocol’’ high-fieldmagnetic resonance imaging (MRI), fluoro-deoxy-glucosepositron emission tomography (FDG-PET), neuropsycho-logical testing, was performed. 3.0-T MRI revealed in-creased T2 signal intensity and volume loss of the righthippocampus (Fig. 1). No cystic lesions or other neo-cortical abnormalities were observed by neuroradi-ologists. Gadolinium enhancement was not performed. Nocalcifying lesions were seen in computed tomographyscans. Video-EEG monitoring revealed that complexpartial seizures with automatisms were associated withrhythmic EEG changes in the right anterior temporalregion. FDG-PET showed glucose hypometabolism in theright antero-basal temporal region. Neuropsychologically,mild impairment of verbal memory function was noted.Under a diagnosis of right TLE with hippocampal scle-rosis, trans-sylvian selective amygdalo-hippocampectomywas performed. Histological examination revealed bothType 1b HS (Fig. 2a) and ganglioglioma in the subiculum(Fig. 2b, c) [1]. He has suffered no additional neuro-logical deficits post-operatively. The patient was seizurefree for 2 years with continuing medication. Follow-upMRI at 1 year showed no evidence for recurrence oftumor.Neocortical epileptogenic lesion occasionally coexistswith HS, and is called ‘‘dual pathology.’’ Surgical re-moval of both neocortical lesion and hippocampus isbetter for the achievement of seizure freedom [2]. In thepresent case, the subicular tumor was not identified pre-
[Corpus callosotomy for children with intractable generalized epilepsy: factors for long-term seizure remission]
No to hattatsu. Brain and development, 2013
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, 2014
Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) im... more Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) imaging. Source localization of EEG and magnetoencephalography (MEG) spikes was evaluated to confirm the diagnosis of small FCD. This study included 6 epilepsy patients with a single small lesion on MR imaging suggesting FCD within a single gyrus among 181 consecutive epilepsy patients admitted to our epilepsy monitoring unit over 27 months. Stereotypical interictal spikes were detected on simultaneous EEG and MEG recordings and the onset-related source of averaged spikes was estimated. All 6 patients had unique clinical characteristics as follows: leg sensori-motor seizures in 5 patients and eye version in 1 patient; a small MR imaging lesion suggesting FCD in the dorsal peri-rolandic region, which had been overlooked until our evaluation; and both EEG and MEG dipoles were estimated adjacent to the MR imaging lesion. Source localization of EEG and MEG spikes can confirm the diagnosis of F...
[A case of focal epilepsy manifesting multiple psychiatric auras]
Brain and nerve = Shinkei kenkyū no shinpo, 2015
We present a case of epilepsy with multiple types of focal seizures that were misdiagnosed as psy... more We present a case of epilepsy with multiple types of focal seizures that were misdiagnosed as psychiatric disorders. A 20-year-old female patient presented with a variety of episodes, including loss of consciousness, deja vu, fear, delusion of possession, violent movements, and generalized convulsions. Each of these symptoms appeared in a stereotypic manner. She was initially diagnosed with a psychiatric disorder and treated with psychoactive medications, which had no effect. Long-term video electroencephalography revealed that her episodes of violent movement with impaired consciousness and secondarily generalized seizure were epileptic events originating in the right hemisphere. High-field brain magnetic resonance imaging for detecting subtle lesions revealed bilateral lesions from periventricular nodular heterotopia. Her final diagnosis was right hemispheric focal epilepsy. Carbamazepine administration was started, which successfully controlled all seizures. The present case demo...
Obsessive-Compulsive Behavior Induced by Levetiracetam
Journal of Child Neurology, 2014
A novel antiepileptic drug, levetiracetam, has been reported to cause several psychiatric adverse... more A novel antiepileptic drug, levetiracetam, has been reported to cause several psychiatric adverse effects in spite of its effectiveness on epilepsy. However, a possible relationship between levetiracetam and obsessive-compulsive behavior has only been reported in a few studies with adult epilepsy patients. We treated a pediatric patient with epilepsy without past or family history of psychiatric disorder. Levetiracetam was started to control generalized tonic-clonic seizure. Two months after initiation of levetiracetam with favorable seizure control, she started to show an obsessive-compulsive behavior such as repetitive checking of her back, pants, and chair. Based on the course of its appearance, levetiracetam administration was identified as a possible cause. After termination of levetiracetam, her obsessive-compulsive behavior completely disappeared with reappearance of seizures. This case provides clear evidence that levetiracetam may cause obsessive-compulsive behavior even in...
Clinical Neurophysiology, 2014
variants on the EEG. Recently, some genes or genetic polymorphisms have been associated with brai... more variants on the EEG. Recently, some genes or genetic polymorphisms have been associated with brain development and eventually with epilepsies associated with structural brain lesions. Thus, it is plausible that some of these genes might also influence epileptogenicity in patients with epilepsy. Accordingly, genes coding Discoidin Domain Receptor Tyrosine Kinase 2 (DDR2), Tescalcin (TESC), and High Mobility Group A Protein (HMGA2) were associated with brain volume, and might influence epileptogenicity. Objective: Investigate the association between DDR2, TESC and HMGA2 genes and interictal spike activity in temporal lobe epilepsy (TLE). Methods: Case-control study of 76 patients with TLE exploring the influence of polymorphisms rs10494373 of DDR2, rs7294919 of TESC and rs10784502 of HGMA2 on the incidence, distribution and lateralization of interictal epileptiform EEG of these patients. All individuals had an awake and asleep standard EEG recordings, and tracings were analyzed by experienced and certified electroencephalographers. Results: No association between rs10494373 of DDR2, and rs7294919 of TESC polymorphisms with EEG spike rates was found in TLE, regarding the EEG variables studied. However, presence of C allele in homozygosis in rs10784502 variant of HGMA2 was associated with significant less interictal discharges (p=0.008), in other words, presence of T allele in this specific polymorphism was associated with a doubling of discharges per minute, when compared with C allele in homozygosis (OR: 2.15±2.99 × 1.01±0.65). Our data allow us to hypothesize that variability in the HMGA2 gene might influence EEG interictal epileptiform activity and epileptogenicity in patients with TLE. We believe that further studies will shed some light on molecular mechanisms involved in the generation of EEG epileptiform activity.
手術で治癒したてんかん患者における術前脳磁図(MEG)スパイクの局在
Paired‐Pulse Stimulationを用いた局所CCEPによるてんかん皮質興奮性の検討
Initial delta and delayed theta/alpha pattern in the temporal region on ictal EEG suggests purely hippocampal epileptogenicity in patients with mesial temporal lobe epilepsy
Clinical Neurophysiology
OBJECTIVE To determine whether the ictal scalp EEG findings suggest purely hippocampal epileptoge... more OBJECTIVE To determine whether the ictal scalp EEG findings suggest purely hippocampal epileptogenicity in patients with mesial temporal lobe epilepsy (mTLE) associated with hippocampal sclerosis (HS). METHODS Twenty-three patients with mTLE with pathologically confirmed HS were divided into 12 with epileptogenicity only in the hippocampus (HS only group) and 11 with epileptogenicity in both the hippocampus and temporal neocortex or other locations (HS plus group), based on the combination of surgical procedures, postoperative outcome, and pathological findings. Sixteen underwent selective amygdalohippocampectomy (SelAH) and 7 received anterior temporal lobectomy. Ictal scalp EEG findings of 79 focal impaired awareness seizures were compared between the HS only and HS plus groups. We focused on the 1-4 Hz rhythmic delta activity at ictal onset followed by 5-9 Hz rhythmic theta/alpha activity 10-30 s after the onset in the temporal region. RESULTS The initial delta and delayed theta/alpha (ID-DT) pattern was observed in 8 of 12 patients in the HS only group, but in none of 11 patients in the HS plus group (p < 0.01). CONCLUSIONS ID-DT pattern on ictal EEG suggests purely hippocampal epileptogenicity in mTLE with HS. SIGNIFICANCE Patients with the ID-DT pattern are likely to become seizure-free after SelAH.
Neuromagnetic localization of spike discharges correlates with postoperative seizure outcome
Japanese Journal of Neurosurgery, 2000
Optogenetic stimulus-triggered acquisition of seizure resistance
Neurobiology of Disease, 2022
Unlike an electrical circuit, the hardware of the brain is susceptible to change. Repeated electr... more Unlike an electrical circuit, the hardware of the brain is susceptible to change. Repeated electrical brain stimulation mimics epileptogenesis. After such "kindling" process, a moderate stimulus would become sufficient in triggering a severe seizure. Here, we report that optogenetic neuronal stimulation can also convert the rat brain to a hyperexcitable state. However, continued stimulation once again converted the brain to a state that was strongly resistant to seizure induction. Histochemical examinations showed that moderate astrocyte activation was coincident with resilience acquisition. Administration of an adenosine A1 receptor antagonist instantly reverted the brain back to a hyperexcitable state, suggesting that hyperexcitability was suppressed by adenosine. Furthermore, an increase in basal adenosine was confirmed using in vivo microdialysis. Daily neuron-to-astrocyte signaling likely prompted a homeostatic increase in the endogenous actions of adenosine. Our data suggest that a certain stimulation paradigm could convert the brain circuit resilient to epilepsy without exogenous drug administration.
[Ictal Speech Manifesting as Sleep Talking: A Case Report]
Brain and nerve = Shinkei kenkyu no shinpo, 2017
We present a 28-year-old female patient whose epilepsy started at the age of 19. MRI showed right... more We present a 28-year-old female patient whose epilepsy started at the age of 19. MRI showed right perisylvian polymicrogyria. She exhibited various seizure symptoms, such as somatosensory aura involving the left leg, dyscognitive seizures, and amnesic seizures. Her mother indicated that the patient sometimes had "sleep talking", which was associated with presence of epileptic seizures of the next day. Long-term video electroencephalography (EEG) revealed that her episodes of "sleep talking" were epileptic events, specifically ictal speech, originating in the right hemisphere. The present case demonstrates the importance of considering "sleep talk" as an epileptic symptom. Careful history taking is fundamental to carry patients with possibly pathological "sleep talk" to the long-term video EEG, which will contribute correct diagnosis and treatment. (Received August 16, 2016; Accepted September 9, 2016; Published February 1, 2017).
Three patients with posterior quadrant epilepsy showing focal ictal EEG onset during NREM sleep, but not during wakefulness
Sleep Medicine, 2015
Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, Jan 19, 2016
To investigate whether seizure lateralization affects sleep macrostructure in patients with left ... more To investigate whether seizure lateralization affects sleep macrostructure in patients with left and right temporal lobe epilepsy (TLE), as rapid eye movement (REM) sleep is shorter in patients with right hemispheric cerebral infarction than with left. We retrospectively analyzed data from 16 patients with TLE (6 men and 10 women aged 34.9 ± 11.4 years) who underwent polysomnography as well as long-term video electroencephalography. Ten patients were diagnosed with left TLE and six patients with right TLE. Sleep stages and respiratory events were scored based on the American Academy of Sleep Medicine criteria. Sleep and respiratory parameters were compared between the patient groups. Percentage of REM stage sleep was significantly (p < 0.05) lower in patients with left TLE (median 8.8 %, interquartile range 5.5-13.8 %) than in patients with right TLE (median 17.0 %, interquartile range 14.1-18.3 %). The other parameters showed no significant differences. Shorter REM sleep in pati...
Epilepsy Research, 2016
Object: The use of T2 relaxometry was investigated to detect non-sclerotic epileptogenic abnormal... more Object: The use of T2 relaxometry was investigated to detect non-sclerotic epileptogenic abnormality of the hippocampus in presurgical evaluation of temporal lobe epilepsy (TLE). Methods: This prospective study included 30 patients who underwent hippocampectomy as part of surgical treatment of refractory TLE. Ten patients had structural epileptogenic lesions in the extra-hippocampal temporal lobe. Twelve patients underwent intracranial electroencephalography (iEEG) study before surgery. Visual assessment of atrophy and increased T2 signal intensity, volumetry, and T2 relaxometry of hippocampus were performed pre-operatively using 3 T magnetic resonance imaging, and compared with the neuropathological findings and iEEG findings. Magnetic resonance imaging of 30 age-and sexmatched healthy controls was used to establish normal values, which were defined as z score within 2. Results: Visual assessment, volumetry, and T2 relaxometry detected hippocampal abnormalities on the surgical side in 16 (53%), 16 (53%), and 26 (87%) patients, respectively. Hippocampal volume loss was always associated with prolonged T2 relaxation time, and supported by histopathological diagnosis of HS in all cases except one. Hippocampal abnormality was detected only by T2 relaxometry in nine patients (30%). Pathological diagnosis of these cases included mild HS in one, microdysgenesis in one, and granule cell pathology in three. Four patients with normal hippocampal volume and T2 relaxation time had no HS or granule cell pathology. Prolonged T2 relaxation time was associated with medial temporal seizure onset in iEEG (p < 0.05). Conclusions: T2 relaxometry improves the detection of non-sclerotic epileptogenic abnormality of the hippocampus.
Surgecal Implications of Neuromagnetic Spike Localization in Temporal Lobe Epilepsy
Epilepsia Journal of the International League Against Epilepsy, Apr 1, 2002
Clinical Neurophysiology, 2015
Introduction. -La dysplasie de trochlée est un des éléments majeurs de l'instabilité fémoropatell... more Introduction. -La dysplasie de trochlée est un des éléments majeurs de l'instabilité fémoropatellaire. Si sa correction par trochléoplastie apparaît logique, le résultat à long terme de cette intervention n'est pas connu et il persiste une incertitude sur l'évolution arthrosique. Aussi, nous avons mené une étude rétrospective d'une série de trochléoplasties de creusement au recul de 15 ans avec pour objectifs : ( ) d'évaluer à long terme les résultats cliniques et le taux radiologique d'arthrose ; (2) de préciser les résultats en fonction du type d'instabilité et du grade de la dysplasie. Hypothèse. -La trochléoplastie de creusement est une intervention efficace sur la stabilisation de l'articulation fémoropatellaire sans augmenter le risque d'arthrose. Patients et méthodes. -Cette étude analyse rétrospectivement 34 trochléoplasties de creusement au moyen de scores cliniques (scores IKS, Lillois, Kujala et Oxford) et leurs résultats radiologiques (stade d'arthrose selon Iwano) au recul moyen de 15 ans (12-19 ans). Une plastie d'Insall était associée systématiquement et une transposition de la tubérosité tibiale antérieure dans 17 cas (7 transpositions préalables). Résultats. -Aucune récidive d'instabilité objective n'a été observée. Six genoux ont été repris par prothèse pour arthrose et un par transposition de la tubérosité tibiale pour douleur et dérobements au recul moyen de 7 ans (2-16). Les scores moyens Lillois, Kujala et IKS passaient respectivement de 53,3 (30-92), 55 (13-75) et 127 (54-184) en préopératoire à 61,5 (25-93), 76 (51-94) et 152,4 (66-200) au recul (p < 0,05) (reprises incluses). Les résultats fonctionnels étaient significativement meilleurs pour les dysplasies avec éperon versus 153 et Kujula 81, versus 76 [51-94] [p < 0,05]). Les patients étaient satisfaits dans 65 % des cas et le score Oxford total moyen étaient de 24,1 points/60 (12-45 points). La douleur était occasionnelle ou nulle dans 53 % des cas. La saillie de la trochlée passait de 4,9 mm (3-9 mm) à -1,2 mm (-7-4 mm). L'arthrose fémoropatellaire, 10 cas en préopératoire mais aucune > Iwano 2, était présente dans 33/34 cas avec 20 cas > Iwano 2 (65 %) au recul. Discussion. -La trochléoplastie de creusement permet la stabilité fémoropatellaire même en cas de dysplasie sévère pour lesquelles elle donne de meilleurs résultats fonctionnels à long terme. En revanche, elle ne prévient pas l'arthrose fémoropatellaire. Elle doit être réservée aux dysplasies sévères avec éperon en l'associant à des gestes de réalignement de l'appareil extenseur. Niveau de preuve. -IV, étude rétrospective de cohorte.
1-A-D-22. Sleep stages affect the occurrence of high frequency oscillations (HFOs) differently between hippocampus and neocortical areas
Clinical Neurophysiology, 2015
This study was aimed to reveal that influence of sleep stages on the occurrence of HFOs was diffe... more This study was aimed to reveal that influence of sleep stages on the occurrence of HFOs was different between anatomical areas. Nine patients underwent extraoperative intracranial EEG monitoring from both hippocampal depth and neocortical subdural electrodes. Interictal HFOs were detected semi-automatically on EEGs taken during different sleep stages. The difference in the occurrence rate of HFOs between NREM3 and REM sleep stages was normalized per patient, and compared between hippocampus and neocortical electrodes. Number of electrodes showing HFOs at higher rate than standard range was compared between sleep stages and anatomical sites. Hippocampal electrodes ( n = 57) showed higher rate of HFOs during NREM3 sleep than neocortical electrodes ( n = 638) ( p p
1-A-D-26. Pre-operative magnetoencephalographic spike localization in patients with surgically-cured epilepsy
Clinical Neurophysiology, 2015
This study investigated the characteristic localization of magnetoencephalographic (MEG) “green” ... more This study investigated the characteristic localization of magnetoencephalographic (MEG) “green” spikes unrelated to epileptogenicity. Preoperative interictal MEG spike localization was compared with surgical resection areas in 17 patients, who achieved complete seizure freedom after withdrawal from antiepileptic medications. No MEG spikes were detected in two patients. In three patients, all MEG spike-areas were resected. Eleven patients had MEG spikes in both resection and other areas. Spike localization remote from resection-area was classified into three types: (1) antero-mesial temporal spikes ( n = 4); (2) contralateral temporal spikes ( n = 3); and (3) posterior temporo-parietal spikes ( n = 5). Both the antero-mesial and contralateral temporal spikes were found only in patients with mesial temporal lobe epilepsy (TLE). The posterior temporo-parietal spikes were found in patients with mesial TLE, as well as other epilepsies. Mesial temporal spikes generated from the hippocampus can propagate to the anterior temporal neocortex and contralateral temporal lobe. Since these temporal neocortical spikes did not reflect epileptogenicity, seizure freedom was achieved after amygdalohippocampectomy. Temporo-parietal spikes found in TLE and other epilepsies can be a “green” MEG spikes. MEG has high sensitivity to activity in the temporo-parietal area, to where spikes propagate easily.
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, Jan 30, 2015
We hypothesized that high frequency oscillations (HFOs) are differently suppressed during rapid e... more We hypothesized that high frequency oscillations (HFOs) are differently suppressed during rapid eye movement sleep (REM) between epileptogenic and less epileptogenic cortices, and that the suppressive effect can serve as a specific marker of epileptogenicity. Intracranial electroencephalography (EEG) was recorded in 13 patients with drug-resistant epilepsy. HFOs between 80 and 200Hz were semi-automatically detected from total 15-min EEG epochs each for REM and slow wave sleep (SWS). z-Score of HFO occurrence rate was calculated from the baseline rate derived from non-epileptogenic cortex. Intracranial electrodes were labeled as REM dominant HFO (RdH) if REM z-score was greater than SWS z-score or as SWS dominant HFO (SdH) if SWS z-score was greater than REM z-score. Relationship of electrode location to the area of surgical resection was compared between RdH and SdH electrodes. Out of 1070 electrodes, 101 were defined as RdH electrodes and 115 as SdH electrodes. RdH electrodes were ...
Occult dual pathology in mesial temporal lobe epilepsy
Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, Jan 30, 2015
Keywords Dual pathology ´Temporal lobe epilepsy Ganglioglioma Negative magnetic resonance imaging... more Keywords Dual pathology ´Temporal lobe epilepsy Ganglioglioma Negative magnetic resonance imagingDear Sir,Hippocampal sclerosis (HS) can appear secondary to neo-cortical epileptogenic lesion in medically refractoryepilepsy, called dual pathology. In the dual pathology, re-moval of both the primary lesion and HS is necessary toachieve better seizure outcome. However, if the primarylesion is not apparent in pre-operative imaging studies,selective surgery to hippocampus may be performed andfollowed by inadequate seizure control. Here, we report acase of dual pathology which was not diagnosed pre-operatively.A 50-year-old man with drug-resistant temporal lobeepilepsy (TLE) was referred to our department forevaluation of surgical treatment. Seizures had started atage 10 years and had become intractable to multiplemedications at age 22 years. He had aura of fear or deja`-vu followed by complex partial seizures 2–3 times amonth despite antiepileptic medications including carba-mazepine and lamotrigine. Previously, he was treatedwith valproic acid, levetiracetam and zonisamide. Com-prehensive presurgical evaluation including video-elec-troencephalography (EEG), ‘‘epilepsy protocol’’ high-fieldmagnetic resonance imaging (MRI), fluoro-deoxy-glucosepositron emission tomography (FDG-PET), neuropsycho-logical testing, was performed. 3.0-T MRI revealed in-creased T2 signal intensity and volume loss of the righthippocampus (Fig. 1). No cystic lesions or other neo-cortical abnormalities were observed by neuroradi-ologists. Gadolinium enhancement was not performed. Nocalcifying lesions were seen in computed tomographyscans. Video-EEG monitoring revealed that complexpartial seizures with automatisms were associated withrhythmic EEG changes in the right anterior temporalregion. FDG-PET showed glucose hypometabolism in theright antero-basal temporal region. Neuropsychologically,mild impairment of verbal memory function was noted.Under a diagnosis of right TLE with hippocampal scle-rosis, trans-sylvian selective amygdalo-hippocampectomywas performed. Histological examination revealed bothType 1b HS (Fig. 2a) and ganglioglioma in the subiculum(Fig. 2b, c) [1]. He has suffered no additional neuro-logical deficits post-operatively. The patient was seizurefree for 2 years with continuing medication. Follow-upMRI at 1 year showed no evidence for recurrence oftumor.Neocortical epileptogenic lesion occasionally coexistswith HS, and is called ‘‘dual pathology.’’ Surgical re-moval of both neocortical lesion and hippocampus isbetter for the achievement of seizure freedom [2]. In thepresent case, the subicular tumor was not identified pre-
[Corpus callosotomy for children with intractable generalized epilepsy: factors for long-term seizure remission]
No to hattatsu. Brain and development, 2013
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, 2014
Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) im... more Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) imaging. Source localization of EEG and magnetoencephalography (MEG) spikes was evaluated to confirm the diagnosis of small FCD. This study included 6 epilepsy patients with a single small lesion on MR imaging suggesting FCD within a single gyrus among 181 consecutive epilepsy patients admitted to our epilepsy monitoring unit over 27 months. Stereotypical interictal spikes were detected on simultaneous EEG and MEG recordings and the onset-related source of averaged spikes was estimated. All 6 patients had unique clinical characteristics as follows: leg sensori-motor seizures in 5 patients and eye version in 1 patient; a small MR imaging lesion suggesting FCD in the dorsal peri-rolandic region, which had been overlooked until our evaluation; and both EEG and MEG dipoles were estimated adjacent to the MR imaging lesion. Source localization of EEG and MEG spikes can confirm the diagnosis of F...
[A case of focal epilepsy manifesting multiple psychiatric auras]
Brain and nerve = Shinkei kenkyū no shinpo, 2015
We present a case of epilepsy with multiple types of focal seizures that were misdiagnosed as psy... more We present a case of epilepsy with multiple types of focal seizures that were misdiagnosed as psychiatric disorders. A 20-year-old female patient presented with a variety of episodes, including loss of consciousness, deja vu, fear, delusion of possession, violent movements, and generalized convulsions. Each of these symptoms appeared in a stereotypic manner. She was initially diagnosed with a psychiatric disorder and treated with psychoactive medications, which had no effect. Long-term video electroencephalography revealed that her episodes of violent movement with impaired consciousness and secondarily generalized seizure were epileptic events originating in the right hemisphere. High-field brain magnetic resonance imaging for detecting subtle lesions revealed bilateral lesions from periventricular nodular heterotopia. Her final diagnosis was right hemispheric focal epilepsy. Carbamazepine administration was started, which successfully controlled all seizures. The present case demo...
Obsessive-Compulsive Behavior Induced by Levetiracetam
Journal of Child Neurology, 2014
A novel antiepileptic drug, levetiracetam, has been reported to cause several psychiatric adverse... more A novel antiepileptic drug, levetiracetam, has been reported to cause several psychiatric adverse effects in spite of its effectiveness on epilepsy. However, a possible relationship between levetiracetam and obsessive-compulsive behavior has only been reported in a few studies with adult epilepsy patients. We treated a pediatric patient with epilepsy without past or family history of psychiatric disorder. Levetiracetam was started to control generalized tonic-clonic seizure. Two months after initiation of levetiracetam with favorable seizure control, she started to show an obsessive-compulsive behavior such as repetitive checking of her back, pants, and chair. Based on the course of its appearance, levetiracetam administration was identified as a possible cause. After termination of levetiracetam, her obsessive-compulsive behavior completely disappeared with reappearance of seizures. This case provides clear evidence that levetiracetam may cause obsessive-compulsive behavior even in...
Clinical Neurophysiology, 2014
variants on the EEG. Recently, some genes or genetic polymorphisms have been associated with brai... more variants on the EEG. Recently, some genes or genetic polymorphisms have been associated with brain development and eventually with epilepsies associated with structural brain lesions. Thus, it is plausible that some of these genes might also influence epileptogenicity in patients with epilepsy. Accordingly, genes coding Discoidin Domain Receptor Tyrosine Kinase 2 (DDR2), Tescalcin (TESC), and High Mobility Group A Protein (HMGA2) were associated with brain volume, and might influence epileptogenicity. Objective: Investigate the association between DDR2, TESC and HMGA2 genes and interictal spike activity in temporal lobe epilepsy (TLE). Methods: Case-control study of 76 patients with TLE exploring the influence of polymorphisms rs10494373 of DDR2, rs7294919 of TESC and rs10784502 of HGMA2 on the incidence, distribution and lateralization of interictal epileptiform EEG of these patients. All individuals had an awake and asleep standard EEG recordings, and tracings were analyzed by experienced and certified electroencephalographers. Results: No association between rs10494373 of DDR2, and rs7294919 of TESC polymorphisms with EEG spike rates was found in TLE, regarding the EEG variables studied. However, presence of C allele in homozygosis in rs10784502 variant of HGMA2 was associated with significant less interictal discharges (p=0.008), in other words, presence of T allele in this specific polymorphism was associated with a doubling of discharges per minute, when compared with C allele in homozygosis (OR: 2.15±2.99 × 1.01±0.65). Our data allow us to hypothesize that variability in the HMGA2 gene might influence EEG interictal epileptiform activity and epileptogenicity in patients with TLE. We believe that further studies will shed some light on molecular mechanisms involved in the generation of EEG epileptiform activity.