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Objective:To analyze the characteristics of stereoelectroencephalography (SEEG) in children with drug-resistant epileptic spasms (ES), and to explore the surgical strategy of children with spastic seizure under the guidance of SEEG.Methods:The clinical data of 156 children with ES who were preoperatively evaluated in the Department of Neurosurgery Ward 3, Tsinghua University Yuquan Hospital from January 2014 to December 2021 were retrospectively reviewed.All children were evaluated in the second stage of stereotactic electrode placement after a non-invasive preoperative evaluation.The characteristics of intracranial EEG, surgical strategy and prognosis were analyzed.Results:A total of 19 eligible children were included, involving 13 boys and 6 girls.The age of first onset and surgical age of them ranged 1 month to 4 years, and 2 years to 13 years, respectively.The SEEG was divided into 3 types in children with ES at the onset.Five children were SEEG type A, presenting with the focal seizure discharges at the beginning and a gradual propagation to widespread fast-wave bursts.Ten children were SEEG type B, presenting a focal leading spike followed by diffused fast-wave bursts.Four children were SEEG type C, presenting a diffuse fast wave rhythm onset.Although some electrode discharges appeared slightly " leading", they covered more than one brain region.After focal resection or thermocoagulation, 13/19 patients did not have the onset of seizures, and 5/19 and 8/19 were graded as SEEG type A, and B, respectively.During the intermittent period of SEEG attacks in children with SEEG type A and B, a significant phenomenon of focal epileptic discharge consistent with the onset of the attack was observed, and surgical removal of these areas effectively controlled spastic seizures.Conclusions:Epileptic spasms may be triggered by a focal neocortical discharge.Intracranial EEG showed that the focal seizure onset evolves into spasm or a focal " leading spike" is a good indicator of surgical prognosis.
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Objective To propose a novel stereo-electroencephalography(SEEG) quantitative measure analyzing ictal high frequency (60-90 Hz) and calculating high frequency epileptogenicity index (HFEI) to localize epileptogenic zone and evaluate epileptogenic network. Methods The clinical presurgical evaluation and SEEG data of 15 patients who were performed SEEG electrodes implantation from April 2015 to March 2016 were analyzed retrospectively. Post-implantation head CT images and 3D MRI data were fused for accurately identifying and locating each electrode contact. Ictal SEEG quantitative measure HFEI was calculated and threshold was set. The epileptogenic network was divided into focal, regional, multiple regional and bilateral ones and the results were compared with the pathological results.Results The epileptogenic network was focal for four patients, regional for four patients, multiple regional for six patients and bilateral for one patient (7/15). In terms of the pathology,two cases with hippocampal sclerosis both showed regional network. In four cases with cerebral malacia, two cases showed multiple regional network and the other two cases showed focal network. In six cases with cortical malformation, three cases showed multiple regional network, the other three cases showed focal, regional and bilateral networks respectively. Conclusions We explored a novel SEEG quantitative measure based on the high frequency power analysis,which is objective and could localize epileptogenic zone and evaluate the epileptic network.
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Objective To study the diversities of imaging, symptoms, electrophysiology and clinical value of the stereoelectroencephalography(SEEG) in patients with mesial temporal lobe epilepsy.Methods Eight patients with intractable epilepsy in Epilepsy Center of Yuquan Hospital of Tsinghua University who underwent mesial temporal lobectomy were recruited in this study, and their epileptic foci could not be accurately positioned.Therefore stereotactic brain electrodes were implanted, and their usual attack originated from mesial temporal lobe structure were confirmed.There was no seizure in the one year follow-up.Results Symptoms of the eight patients behaved differently, and the onset of the seizures in scalp electroencephalograph or SEEG showed diversities.Epileptic discharges were found originated from the mesial temporal lobe after implanting electrodes: in the early stage of discharges, four cases had the conduction to insular lobe structure;two cases had the conduction to contralateral mesial temporal lobe;one case had the conduction to retrosplenial cortex;one case had the conduction to parietal lobe;one case had the conduction to frontal lobe and rapid generalization (one case had the conduction to insular lobe and contralateral mesial temporal lobe meanwhile).Conclusions There is difference in clinic, imaging and electrophysiology of the patients with mesial temporal lobe epilepsy The non-specificity can be explained by the evolution of the intracranial electroencephalography, which can help us know its network conduction pattern Insular lobe is the most common conduction approach of mesial temporal lobe epilepsy in early stage SEEG can be used as a microinvasive, accurate preoperative localization method, which can help us to locate accurately and understand the discharges and conduction mode.
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BACKGROUND: Some cases of paradoxical mesial temporal lobe epilepsy (MTLE) are shown to be bilateral MTLE (BMTLE) by intracranial electrodes. The treatment for BMTLE is difficult, which poses several questions. Can corticoamygdalohippocampectomy (CAH) be applied to treat BMTLE? What are the long-term therapeutic effects if CAH is performed in BMTLE patients? METHODS: Four patients were shown to have BMTLE through bilateral intracranial electrode implantation. CAH was performed on the side with relatively more seizure originations. These patients were followed-up at 6 months, 1 year, 2 years and longer, in some cases, after the CAH. The postoperative seizure frequency was recorded. Preoperative and postoperative clinical memory tests and a postoperative 4-hour video electroencephalography (EEG) were conducted in the hospital at different follow-up times. The average seizure frequencies and memory quotient scores were analyzed. RESULTS: The average seizure frequency significantly decreased by 80.8%, 83.5%, and 84.3% at different postoperative times. Although no patient was seizure free, the intensity of the seizures was reduced in all cases. The postoperative average memory quotient score was moderately decreased by 15.8%, 11.7%, and 16.6% at different postoperative times. Both the average values of the postoperative seizure frequency (5.5, 4.75, and 4.5 per month) and the average values of the postoperative memory quotient (73.7, 77.3, and 73) at different postoperative times were approximately the same. CONCLUSIONS: CAH reduced the seizure frequency and intensity in these BMTLE patients. Mild hypomnesis occurred in every case. We observed the long-term treatment effects at 6 months after the CAH and showed that the effects did not change at that time or over the next few years.
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ObjectiveTo investigate the clinic and pathologic features of one patient diagnosed with neurocutaneous melanosis ( NCM ) by biopsy.MethodsA 21-year-old woman presented with a 2-month history of tinnitus,headache,vomiting and 1-month history of impaired vision.At birth,a massive nevus covering most of the posterior abdomen had been noted as well as the presence of multiple smaller lesions all over the body.Magnetic resonance imaging demonstrated a posterior fossa cyst compatible with the Dandy-Walker syndrome and extensive leptomeningeal enhancement. Surgery was performed to cystectomy and to obtain pathologic specimens from the leptomeninges. Biopsy and immunohistochemical study was performed.ResultsAt surgery,diffuse black pigmentation of the leptomeninges and the cyst was found.Under microscope,the cyst and leptomeninges were composed with melanocytes with variable pigmentation.Those cells positive for HMB45,MelanA,S100 and vimentin.Ki-67 positive cells ＜ 1％.The pathologic diagnosis wasleptomeningeal diffusemelanocytosis. Thepatientdied 2months after thesurgery.ConclusionsNCM is characterized by a focal or diffuse proliferation of melanin-producing cells in both the skin and the leptomeninges.NCM could be compatible with the Dandy-Walker syndrome.Definite diagnosis relies upon the histological data obtained by mean of biopsy.
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PURPOSE: To explore the diagnostic value of intracranial electrodes in highly suspected temporal lobe epilepsy (TLE) and the value of sphenoid electrodes (PG) and the propagation patterns of ictal discharges in focus lateralization. METHODS: Intracranial electrodes were implanted in 22 probable TLE patients through bilateral temporal burr holes. Extracranial electrodes included the 10-20 international EEG system and bilateral PGs. Intracranial and extracranial EEGs (IEEG, EEEG) were synchronously recorded. The interictal epileptic discharges (IEDs) were counted for 3h of interictal preoperative long-playing video EEG. Time intervals between electrodes recording the ictus and ictus occurring were measured and the propagation patterns were deduced. RESULTS: By IEEG, 18 patients with confirmed TLE had surgery; 14 were seizure-free. 3 had FLE, and 1, uncertain localization. Of the 14 TLE and postoperative seizure-free patients, the ratio (left:right) of IEDs in the 3h interictal EEG was 483:211 in the 6 left TLE and 263:654 in the 8 right TLE. In 12 of the 14 cases, the side with more IEDs at PG was the epileptic focus side. In 11 of the 14 cases the earlier PG recording side was focus side. We found that the propagation sequence of ictus followed certain rules in most attacks. CONCLUSIONS: The results indicated that IEEG was useful for final diagnosis of highly suspected TLE and that PG was helpful in focus lateralization. The propagation patterns of ictus might provide a new tool in focus lateralization and localization.
