Gelastic seizures involving the right parietal lobe.

Gelastic seizures have been described in various epilepsies arising from the temporal or frontal lobes, although the most commonly encountered form is related to the presence of an hypothalamic hamartoma. We report a patient with gelastic seizures involving the right parietal lobe. Our patient, a 32-year-old man, underwent video-EEG monitoring, interictal and ictal brain SPECTs during gelastic seizures. Subtraction ictal SPECT co-registered to MRI (SISCOM), was performed to localize any ictal hyperperfusion during these gelastic seizures. The seizures consisted of brief staring followed by smiling and laughing. Electroencephalography during the gelastic seizures showed rhythmic sharp waves in the right parietal lobe. SISCOM showed ictal hyperperfusion in the right parietal lobe and medial portions of right cerebellum. Our findings suggest that the right parietal lobe may actively participate in the particular epileptogenic network generating gelastic seizures.     

Eating seizures associated with focal cortical dysplasia.

A 15-year-old boy in whom seizures were precipitated by drinking is described. Ictal EEG showed biparietal slow-wave discharges of greater amplitude over the right parietal lobe. Cerebral MRI disclosed right parieto-occipital cortical dysplasia. The mechanism which may be responsible for the seizures is briefly discussed.     

Gelastic seizures due to hypothalamic hamartoma: Rapid resolution after endoscopic tumor disconnection

Gelastic epilepsy are focal seizures manifesting as recurrent brief seizures starting as laughter or grimaces. They are most commonly associated with other types of seizures and can be secondary to infectious, malformative, metabolic, or neoplastic processes involving the central nervous system. We report on an 18-month-old girl who presented since the age of 2 months with multiple, recurrent, unprovoked episodes of stereotypical laughter. Brain magnetic resonance study revealed an hypothalamic hamartoma. Endoscopic tumor disconnection of the hamartoma resulted in rapid resolution of neurological symptomatology.     

Gelastic epilepsy and dysprosodia in a case of late-onset right frontal seizures

Gelastic epilepsy (GE) is an uncommon type of seizure disorder characterized by stereotyped, unprovoked, inappropriate ictal laughter. GE is most frequently associated with hypothalamic hamartoma, with onset almost invariably occurring during childhood. GE also occurs occasionally with temporal and frontal cortical seizure foci. We describe an unusual case of senescent-onset GE with a right frontal seizure focus. In addition to laughter, dysprosodia was a clinical feature. Clinical and electroencephalographic evidence of seizure activity ceased on levetiracetam, and the patient showed concurrent improvement in cognitive function. We review the evidence for the cerebral representation of laughter and prosody, and discuss issues bearing on the differential diagnosis and management of GE.     

Gelastic seizures: not always hypothalamic hamartoma.

Gelastic seizures are often associated with hypothalamic hamartomas. However, focal cortical dysplasias can also cause "laughing seizures", and such cases can be difficult to localize with EEG. This case report presents a 29-year-old woman who was successfully rendered free of gelastic seizures after resection of a frontal cortical dysplasia, localized through MRI and SPECT imaging.[Published with video sequences].     

局限性脑皮质发育不良继发顽固性癫痫的手术治疗

目的 探讨局限性脑皮质发育不良（FCD）的诊断、影像学和电生理学特点，以及手术治疗的策略与方法。方法 1996年6月至2003年12月在意大利米兰NiguardaCa’Granda医院手术治疗的442例癫痫患者中，根据该中心提出的FCD病理学分类标准，对81例诊断为FCD的病例进行回顾性研究。其中皮层组织结构发育异常（AD）42例、细胞组织结构发育异常（CD）12例、Taylor脑皮质发育不良（TFCD）27例。患者术前均行MRI、VEEG检查，61％的患者还接受了立体脑电图检查（SEEG）。结果 术前MRI检查阳性率65％。癫痫术后随访1年以上总治愈率为54％（Engle Ia），其中AD组为49％、CD组45％、TFCD组69％。FCD病理分型的不同与癫痫发作频率、致痫灶部位以及手术效果有关。AD组致痫灶常见于颞叶，癫痫发作次数少于CD和TFCD组。而TFCD常发生于颞叶以外的部位，SEEG发作间期显示有典型的放电节律，且手术愈后较好。结论 该分类标准简单且易于操作，对分析临床表现与判定手术效果有指导意义。SEEG技术在研究FCD，特别是TFCD电生理特征有独特的优势，并为术前准确定位致痫灶范围、保证手术效果提供了重要保障。     

Ictal asomatognosia due to dominant superior parietal cortical dysplasia

We report a 23-year-old man with left dominant parietal cortical dysplasia manifesting as ictal asomatognosia. The man had experienced seizures, during which he underwent ictal asomatognosia as a feeling of loss of his right extremities. Scalp electroencephalography (EEG) showed interictal discharges in the left parietal region of his brain. Magnetic resonance fluid-attenuated inversion recovery (FLAIR) imaging revealed a hyperintense lesion in the left superior parietal lobule. A [¹²³I]-iomazenil (IMZ) single-photon-emission CT scan demonstrated an area of low IMZ binding coincident with the lesion observed in the MRI scan. Invasive EEG monitoring showed ictal discharges in the cortex posterior to the postcentral sulcus. High-frequency electrical stimulation of the same area of the cortex also induced asomatognosia of the patient’s right forearm. We performed a corticectomy of the anterior part of the superior parietal lobule, which resulted in no new neurological deficits. The seizures disappeared after surgery with the maintenance of preoperative medication. Therefore, the anterior part of the superior parietal lobule may be a symptomatogenic zone for ictal asomatognosia.     

Seizure outcome after temporal lobectomy in temporal lobe cortical dysplasia

PURPOSE: To identify the temporal lobe cortical dysplasia (CD) histopathology classification subtype and determine the seizure outcome of patients who underwent temporal lobectomy with coincident CD. METHODS: We reviewed the data of 28 patients with temporal lobe epilepsy who underwent surgery with pathologically verified CD at our institution from 1990 to 2000. The seizure outcome was assessed at a minimum of 1 year after surgery according to Engel's classification. RESULTS: Of 28 patients who underwent surgery, nine (32.1%) had isolated CD, and 19 (67.9%) had CD and hippocampal sclerosis (CD&HS). Twenty-six (92.9%) patients had histopathology subtype Ia (architectural abnormalities). Twenty (71.4%) patients were seizure free (Engel class I). Favorable seizure outcome (Engel class I, II) was achieved in 26 (92.9%) patients. No difference in seizure outcome was noted between patients with CD and CD&HS. CONCLUSIONS: The most common histopathologic subtype in patients with temporal lobe CD is type Ia (architectural abnormalities). Temporal lobectomy in temporal lobe epilepsy patients with CD can achieve favorable seizure outcome.     

Gelastic seizures involving the left parietal lobe

Gelastic seizures have been described in various epilepsies arising from the temporal or frontal lobes, although the most commonly encountered form is related to the presence of a hypothalamic hamartoma. We describe a patient with gelastic seizures involving the left parietal lobe. Our patient, an 8-year-old girl, underwent interictal video/EEG monitoring and MRI. The seizures consisted of brief staring followed by smiling and laughing. Electroencephalography during the gelastic seizures showed rhythmic spikes and waves in the left parietal lobe. MRI revealed the characteristic features of focal cortical dysplasia. Our findings suggest that the left parietal lobe may actively participate in the particular epileptogenic network generating gelastic seizures.     

Infantile partial seizures due to temporal lesions--analysis of 4 cases

We studied 4 cases of complex partial seizures due to temporal lesions presenting with benign partial epilepsy in infancy. None of them had neurologic abnormalities. All cases had complex partial seizures, and two had lateralizing signs. All cases had temporal lesions. One of them was detected only by fluid-attenuated inversion recovery (FLAIR) imaging. Histopathologically they were astrocytomas (grade 2 and 3), glio neuronal hamartoma and focal cortical dysplasia. The present cases suggest that patient with infantile complex partial seizures should be carefully followed up, even after the disappearance of seizures, by serial MRI examination including FLAIR imaging and by clinical observation.     

Co-existence of cavernoma and cortical dysplasia in temporal lobe epilepsy.

Cavernomas and cortical dysplasia are well-known causes of partial epilepsy. The association between cavernoma and cortical dysplasia in an epileptic patient has not yet been sufficiently documented. We report a case of long-term, drug-resistant, partial left temporal epilepsy associated with a cavernoma. According to the neurophysiological non-invasive presurgical study, the patient was submitted to a tailored left temporal resection. The histopathological study showed the coexistence of cavernoma and cortical dysplasia. This is an interesting combination of epilepsy-related pathologies that have so far not been documented.     

Recurrent intractable seizures in children with cortical dysplasia adjacent to dysembryoplastic neuroepithelial tumor

The purpose of this study was to identify the pathologic features that predict postoperative outcome in children with cortical dysplasia adjacent to dysembryoplastic neuroepithelial tumors. We reviewed the records of children with dysembryoplastic neuroepithelial tumor who underwent epilepsy surgery and who had at least 1 year of surgical follow-up. We divided the dysembryoplastic neuroepithelial tumors into three pathology classes (simple, complex, and nonspecific), categorized adjunctive cortical dysplasia into four types, and compared histopathology with seizure outcomes. We identified 26 children with dysembryoplastic neuroepithelial tumors. Dysembryoplastic neuroepithelial tumors were complex in 19 patients (73%), simple in 6 (23%), and nonspecific in 1 (4%). Cortical dysplasia was adjacent to dysembryoplastic neuroepithelial tumors in 18 patients. Six patients had type IA cortical dysplasia, 5 had type IB, 3 had type IIA, and 1 had type IIB. The 3 remaining patients had repeated surgeries; of these, 2 patients had cortical dysplasias of type IA/IB and 1 was type IIA/IIB. Eight (39%) of 18 patients with dysembryoplastic neuroepithelial tumors and cortical dysplasia required further surgery for recurrent intractable seizures (P < .05), whereas none of 8 patients without cortical dysplasia required additional surgery. Of 13 patients with type I cortical dysplasia, only 4 had a poor seizure outcome, whereas all 5 patients with type II had a poor seizure outcome postoperatively (P < .05). Children with dysembryoplastic neuroepithelial tumor and cortical dysplasia often had recurrent intractable seizures postoperatively and required further epilepsy surgery. Cortical dysplasia adjacent to dysembryoplastic neuroepithelial tumor can play a role in the epileptogenicity of dysembryoplastic neuroepithelial tumor. Complete resection of a dysembryoplastic neuroepithelial tumor and its adjacent cortical dysplasia should be considered.     

Surgical treatment of epilepsy due to cortical dysplasia: clinical and EEG findings.

Seventeen patients with cortical dysplasia who had surgical resection for medically intractable partial epilepsy were studied. Compared with two groups of surgically treated patients with intractable epilepsy due to tumour (n = 20) and mesial temporal sclerosis (n = 40), patients with cortical dysplasia showed significantly more frequent extratemporal lesions, more frequent non-epileptiform EEG abnormalities and less favourable surgical outcome for seizure control. Patients with cortical dysplasia were younger at onset of seizures and had a lower detection rate of CT abnormalities compared with the tumour group, and lower IQ compared with the mesial temporal sclerosis group. MRI was abnormal in five of seven patients. Six patients became seizure-free or almost seizure-free but eight did not experience relief of seizures. Surgical outcome related to the extent of pathology but not to the histological abnormality. Lesions outside the temporal and frontal lobes were correlated with poor surgical outcome, as were generalised interictal EEG abnormalities, which may reflect extensive or multiple lesions. Ictal intracranial recordings were not useful for presurgical evaluation of cortical dysplasia.     

Paroxysmal alien limb phenomena due to epileptic seizures and electrical cortical stimulation

Alien limb phenomena (ALPs) are characterized by limb movements, which are subjectively experienced as involuntary or alien induced. ALPs regularly remain unchanged and occur as a consequence of frontal, callosal, or posterior cerebral lesions. The authors present two patients with paroxysmal ALP proved to be focal seizures by using video-EEG monitoring. In another two patients, ALP could experimentally be induced by electrical cortical stimulation. Based on the stimulation results, the authors suspect a functional disconnection of 1) sensory cortical areas providing information about the extrapersonal space; and 2) areas of the frontal and/or limbic cortex that are regularly involved in the processing and executing of intentional motor activity as a pathophysiologic substrate for ictal ALP.     

Freeze lesion-induced focal cortical dysplasia predisposes to atypical hyperthermic seizures in the immature rat

Summary: Purpose: To determine the effects of focal cortical dysplasia on the behavioral and electrographic features of hyperthermia‐induced seizures (HSs) in rats. Methods: A right sensorimotor cortex freeze lesion was induced in postnatal day 1 (P1) rat pups, and HSs were provoked at P10 under continuous monitoring of core temperature; EEGs were recorded from the right amygdala during and after hyperthermia. Controls included both sham‐operated at P1 and naïve rats. Results: HSs began with jaw myoclonus, followed by hindlimb clonus and generalized convulsions (GCs), and terminated by a period of posthyperthermia depression. The threshold temperature and latency of jaw myoclonus were similar across the groups. However, both the threshold temperature and latency of GCs were significantly lower in lesioned pups than in controls (40.5 ± 0.5°C, n = 24, vs. 42.0 ± 0.2°C, n = 21; p < 0.001; 6.7 ± 0.6 min, n = 20, vs. 8.4 ± 0.6 min, n = 22; p < 0.05). In lesioned pups, the threshold and latencies for jaw myoclonus and hindlimb clonus were similar, whereas in controls, the progression from one to the other was marked by significant differences in both parameters. Posthyperthermia depression was longer in lesioned (13.3 ± 1.2 min, n = 21) than in control (8.0 ± 0.8 min, n = 20; p < 0.0001) pups. Ictal EEG activity was recorded during both behavioral seizures and posthyperthermia depression. Conclusions: An HS in rats with a localized freeze lesion results in lower threshold GC and prolonged ictal manifestations, thus supporting a pathophysiologic link between focal cortical dysplasia and atypical febrile seizures, conditions that have a high prevalence in children with mesial temporal lobe epilepsy.     

Ictal SPECT in children with partial epilepsy due to focal cortical dysplasia

We studied the usefulness of ictal single-photon emission computed tomography in the presurgical evaluation of children with partial epilepsy resulting from focal cortical dysplasia. Fifteen children, age 1-18 years, were identified with partial epilepsy caused by focal cortical dysplasia (confirmed by histology) who underwent subtraction ictal single-photon emission computed tomography during presurgical evaluation. All children later underwent surgery at the Cleveland Clinic Epilepsy Center between 1996 and 2000. The findings of ictal single-photon emission computed tomography and brain positron emission tomography were classified as localized when "localizing and concordant" with the surgical resection site, nonconcordant when "localizing but not concordant" with the surgical resection, or nonlocalized when "no well-localized region of ictal hyperperfusion was observed on the difference image". In 15 patients, age 1.5-18 years (median age 8 years), epilepsy was classified as frontal in 7, posterior temporal/occipital in 3, temporal in 2, multilobar in 2, and parietal in 1. Of 15 patients, preoperative magnetic resonance imaging revealed focal cortical dysplasia in 11, positron emission tomography was localized in 9, and ictal single-photon emission computed tomography was localized in 8 patients. In 4 patients with normal magnetic resonance imaging but scalp electroencephalographic findings of partial epilepsy, ictal single-photon emission computed tomography and positron emission tomography were localized in 3 each. Fourteen patients were monitored for 6-39 months (mean 20 months). Six of 7 patients (85%) with localized ictal single-photon emission computed tomography compared with 4 of 7 (57%) with nonconcordant/nonlocalized ictal single-photon emission computed tomography had no seizures at follow-up. In 4 patients with normal magnetic resonance imaging, 3 patients with localized ictal single-photon emission computed tomography were free of seizures compared with 1 with nonconcordant ictal single-photon emission computed tomography who continued to have seizures. Ictal single-photon emission computed tomography is a useful adjunctive test in presurgical evaluation of children with refractory partial epilepsy due to focal cortical dysplasia, especially when brain magnetic resonance imaging is normal.     

Low-frequency transcranial magnetic stimulation for epilepsia partialis continua due to cortical dysplasia

The potential therapeutic role of repetitive transcranial magnetic stimulation (rTMS) in epilepsy has been increasingly recognized. We investigated the effects of low-frequency rTMS in a patient with epilepsia partialis continua (EPC) due to cortical dysplasia. A 31-year-old female patient experienced EPC in the right upper and lower extremities, which had lasted for 15 years without generalized seizures. MRI showed focal megaencephaly around the motor cortex suggestive of cortical dysplasia. A figure of eight magnetic coil was placed over the hand motor area, and 100 stimuli with an intensity at 90% of motor threshold were given at 0.5 Hz. Immediately after rTMS, EPC was nearly abolished. The effects had continued approximately for 2 months, and the second trial resulted in the similar effects and time-course. Low-frequency rTMS was safe and well tolerated in this patient. These findings support the concept that rTMS decreases cortical excitability, and may be an effective treatment for focal partial seizures.