Child ; Epilepsy ; pathology ; surgery ; Humans ; Male ; Treatment Outcome ; Tuberous Sclerosis ; pathology ; surgery

Focal cortical dysplasia (FCD) is one of the most common causes of drug-resistant epilepsy. Dysmorphic neurons are the major histopathological feature of type II FCD, but their role in seizure genesis in FCD is unclear. Here we performed whole-cell patch-clamp recording and morphological reconstruction of cortical principal neurons in postsurgical brain tissue from drug-resistant epilepsy patients. Quantitative analyses revealed distinct morphological and electrophysiological characteristics of the upper layer dysmorphic neurons in type II FCD, including an enlarged soma, aberrant dendritic arbors, increased current injection for rheobase action potential firing, and reduced action potential firing frequency. Intriguingly, the upper layer dysmorphic neurons received decreased glutamatergic and increased GABAergic synaptic inputs that were coupled with upregulation of the Na⁺-K⁺-Cl^- cotransporter. In addition, we found a depolarizing shift of the GABA reversal potential in the CamKII-cre::PTEN^flox/flox mouse model of drug-resistant epilepsy, suggesting that enhanced GABAergic inputs might depolarize dysmorphic neurons. Thus, imbalance of synaptic excitation and inhibition of dysmorphic neurons may contribute to seizure genesis in type II FCD.
Animals ; Drug Resistant Epilepsy/surgery* ; Epilepsy/pathology* ; Malformations of Cortical Development/pathology* ; Malformations of Cortical Development, Group I ; Mice ; Neurons/pathology* ; Seizures/pathology*

Cerebral Cortex ; physiology ; Electric Stimulation Therapy ; Electroencephalography ; Epilepsy ; pathology ; physiopathology ; surgery ; Female ; Glioma ; pathology ; physiopathology ; surgery ; Humans ; Middle Aged

Brain ; abnormalities ; pathology ; surgery ; Child, Preschool ; Epilepsy ; etiology ; Humans ; Magnetic Resonance Imaging ; Male

We evaluated the surgical effects of the callosotomy, particularly with respect to the effect of callosotomy in some seizure types and the extent of surgery. Twenty-one patients with a minimum follow-up of two year were enrolled. The most significant effect of callosotomy was the complete suppression of the generalized seizures associated with drop attack in 12 of 21 patients and seizure reduction of more than 75% in 6 of 21 patients. The surgical effect on the partial seizures was very variable. Transient disconnection syndrome appeared in 4 patients after anterior callosotomy. Total callosotomy by staged operation significantly suppressed generalized seizures associated with drop attack without any disconnection syndrome. Our data show that callosotomy is quite a good approach to the surgical treatment of drop attacks accompanied by disabling generalized seizures.
Adolescent ; Adult ; Child ; Corpus Callosum/*surgery ; Electroencephalography ; Epilepsy, Generalized/pathology/*surgery ; Female ; Human ; Magnetic Resonance Imaging ; Male ; Prognosis ; Treatment Outcome

OBJECTIVETo study the immunohistochemical expression and diagnostic significance of CD34 in brain tumors of patients with refractory epilepsy.

METHODSImmunohistochemical study for CD34 was performed on formalin-fixed paraffin-embedded tissue blocks of 54 cases of brain tumors occurring in patients with refractory epilepsy. The tumor types included ganglioglioma (GG, number = 21), dysembryoplastic neuroepithelial tumor (DNT, number = 8), tumors/lesions which had the transitional features that between glioneuronal hamartia and mixed neuronal-glial tumor (number = 21) and pleomorphic xanthoastrocytoma (PXA, number = 4). Cases of glioblastoma (number = 4) and oligoastrocytoma (number = 5) were used as controls.

RESULTSTwenty of the 21 cases of GG, 1 of the 8 cases of DNT, 16 of the 21 cases of tumors/lesions which had the transitional features and 3 of the 4 cases of PXA showed cytoplasmic and membranous positivity for CD34. The adjoining brain tissues in 9 of the 18 cases of GG, 6 of the 16 cases of tumors/lesions which had the transitional features and 1 of the 3 cases of PXA also expressed CD34. In contrast, only 1 case of glioblastoma showed membranous positivity for CD34.

CONCLUSIONSCD34 preferred to staining for GG and PXA. Which represent a valuable tool for distinguishing GG, PXA and DNT, oligoastrocytoma, glioblastoma.

Antigens, CD34 ; metabolism ; Astrocytoma ; complications ; metabolism ; pathology ; surgery ; Brain Neoplasms ; complications ; metabolism ; pathology ; surgery ; Diagnosis, Differential ; Epilepsy ; etiology ; Ganglioglioma ; complications ; metabolism ; pathology ; surgery ; Glioblastoma ; complications ; metabolism ; pathology ; Humans ; Neoplasms, Neuroepithelial ; complications ; metabolism ; pathology ; surgery

OBJECTIVETo investigate pathological changes in the epileptogenic foci of children with intractable epilepsy and their clinical significance.

METHODSThirty children with intractable epilepsy were included in the study. The epileptogenic foci were surgically resected and pathological changes in the obtained specimens were observed under a light microscope (LM) and a transmission electron microscope (TEM).

RESULTSUnder the LM, cortical dysplasia was found in 14 cases (47%), hippocampal sclerosis in 11 cases (37%), dysembryoplastic neuroepithelial tumor in 1 case (3%), ganglioglioma in 1 case (3%), and encephalomalacia in 3 cases (10%). The TEM observation revealed pathological changes in the ultrastructure of the hippocampus and extra-hippocampal cortex, such as changes in the number of synapses and synaptic structure, decrease in neurons and karyopyknosis, swelling and degeneration of astrocytes, and changes in mitochondrial structures.

CONCLUSIONSPathological changes in the hippocampus and extra-hippocampal cortex, especially synaptic remodeling, may be the morphological basis for spontaneous recurrent seizures in children with intractable epilepsy. The pathological changes and epileptiform activity are related to an imbalance between excitatory and inhibitory neurotransmission.

Adolescent ; Brain ; pathology ; ultrastructure ; Cerebral Cortex ; pathology ; ultrastructure ; Child ; Child, Preschool ; Epilepsy ; pathology ; surgery ; Female ; Hippocampus ; pathology ; ultrastructure ; Humans ; Infant ; Intelligence ; Male ; Microscopy, Electron, Transmission

PURPOSE: This study was conducted to assess the clinical relevance of diffusion tensor tractography (DTT) in pre- and post-operative evaluations of childhood epilepsy surgery. MATERIALS AND METHODS: Seventy-two patients who received epilepsy surgery between March 2004 and July 2008 were retrospectively analyzed (M : F=40 : 32, ages of 3 months to 24 years, mean age=8.9 years). DTT was performed using a 3.0 T scanner and single-shot spin-echo echo-planar imaging with 32-different diffusion gradient directions. We reviewed the data focusing on the type of surgery, final pathological diagnosis, and how the DTT data were clinically used. RESULTS: The most common form of childhood epilepsy surgery was complete resection of an epileptogenic lesion (n=52, 72.2%). The reported etiologies included cortical dysplasia (n=32, 44.4%), hippocampal sclerosis (n=9, 12.5%), brain tumors (n=7, 9.7%), and non-pathologic lesions (n=4, 5.6%) in the final diagnoses. Twenty-one dysplastic cortexes and four brain tumors involved an approximal relationship with the corticospinal tract (n=18), optic radiation (n=2), and arcuate fasciculus (n=5). Additionally, although DTT demonstrated white matter tracts clearly, DTT in the hippocampal sclerosis did not provide any additional information. In cases of callosotomy (n=18, 25%), post-operative DTT was utilized for the evaluation of complete resection in all patients. DTT information was not used in functional hemispherectomy (n=2, 2.8%). CONCLUSION: Preoperatively, DTT was a useful technique in cases of cortical dysplasia and brain tumors, and in cases with callosotomy, postoperatively. DTT should be included among the routine procedures performed in management of epilepsy.
Adolescent ; Adult ; Brain Neoplasms/pathology/surgery ; Child ; Child, Preschool ; Diffusion Tensor Imaging/*methods ; Epilepsy/*pathology/*surgery ; Female ; Hippocampus/pathology ; Humans ; Infant ; Male ; Retrospective Studies ; Sclerosis/pathology/surgery ; Seizures/surgery ; Treatment Outcome ; Young Adult

OBJECTIVETo discuss the presurgical evaluation and surgical treatment of lesional temporal lobe epilepsy (LTLE).

METHODSWe retrospectively studied the patients whose MRI or CT showed lesions on one of the temporal lobes among patients who underwent epilepsy surgeries in our institute. All patients were divided into satisfactory and unsatisfactory group according to outcomes after operation. The characteristics of the lesions, neurophysiological features and results of pathologies were analyzed statistically.

RESULTFavorable surgical outcome was obtained in 24 patients, the satisfactory rate was 75%. The lesions of 17 patients were cortical malformations and the satisfactory rate of this group was 65%, which was less favorable than that of tumor group, (87%). 21 patients with their lesions located within the border of standard temporal lobectomy, had better surgical outcome than the others whose lesions were beyond the border (P<0.05). The satisfactory rate of 8 patients with lesions located within mesial structure of temporal lobe was no different compared with that of the others who had lesions outside the mesial structure (P>0.05). There were 19 patients who had consistency of the location of the lesion on MRI with the focal interictal epileptiform discharges on scalp EEG in satisfactory group, while there were only 3 patients in unsatisfactory group (P<0.05).

CONCLUSIONFor a LTLE patient, epilepsy surgery should be the first choice to be considered. Careful presurgical studies of the lesion, including its location, pathological property and neurophysiological characteristics, were very helpful for improving the surgical outcome.

Adolescent ; Adult ; Child ; Child, Preschool ; Epilepsy, Temporal Lobe ; pathology ; surgery ; Female ; Humans ; Male ; Middle Aged ; Psychosurgery ; methods ; Retrospective Studies ; Temporal Lobe ; pathology ; surgery ; Treatment Outcome

BACKGROUNDThe aim of this study is to explore the treatment and outcome of epileptogenic temporal lobe cavernous malformations (CMs).

METHODSWe analyzed retrospectively the profiles of 52 patients diagnosed as temporal lobe CMs associated with epilepsy. Among the 52 cases, 11 underwent a direct resection of CM along with the adjacent zone of hemosiderin rim without electrocorticogram (ECoG) monitoring while the other 41 cases had operations under the guidance of ECoG. Forty-six patients were treated by lesionectomy + hemosiderin rim while the other six were treated by lesionectomy + hemosiderin rim along with extended epileptogenic zone resection. The locations of lesions, the duration of illness, the manifestation, the excision ranges and the outcomes of postoperative follow-up were analyzed, respectively.

RESULTSAll of the 52 patients were treated by microsurgery. There was no neurological deficit through the long-term follow-up. Outcomes of seizure control are as follows: 42 patients (80.8%) belong to Engel Class I, 5 patients (9.6%) belong to Engel Class II, 3 patients (5.8%) belong to Engel Class III and 2 patients (3.8%) belong to Engel Class IV.

CONCLUSIONPatients with epilepsy caused by temporal CMs should be treated as early as possible. Resection of the lesion and the surrounding hemosiderin zone is necessary. Moreover, an extended excision of epileptogenic cortex or cerebral lobes is needed to achieve a better prognosis if the ECoG indicates the existence of an extra epilepsy onset origin outside the lesion itself.

Adolescent ; Adult ; Child ; Electroencephalography ; Epilepsy ; surgery ; Female ; Hemangioma, Cavernous, Central Nervous System ; surgery ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Temporal Lobe ; pathology ; surgery ; Treatment Outcome ; Young Adult