Search

Background: Paediatric epilepsy surgery reduces seizure burden in drug-refractory epilepsy reducing long-term neurocognitive damage. Methods: Single-centre retrospective audit of pre-surgical evaluations and outcomes of the paediatric epilepsy and epilepsy surgery programme over eleven years at KK Women’s and Children’s Hospital, Singapore. Data were collected based on National Institute of Neurological Disorders and Stroke Common Data Elements guidelines. Outcome was categorized using Engel classification scale, and favourable outcome defined as greater than 50% decrease in seizure frequency or drop attacks. Results: Thirty-three children underwent epilepsy surgery, with mean follow-up 3.8±3.1 years. Median age at surgery was 10.9 years. Twenty-four children with focal epilepsy underwent resection of the epileptogenic focus, including lesionectomy (n=8), anterior temporal lobectomy (n=7), extratemporal lobectomy (n=7) and hemispherectomy (n=2). Nine children underwent corpus callosotomy for Lennox Gastaut Syndrome (n=8) and West Syndrome (n=1). Median hospital stay duration was ten days. All twenty-three focal epilepsy patients with minimum three-month follow-up achieved greater than 50% seizure reduction. Fifteen (65%) focal epilepsy patients achieved seizure-freedom (Engel Class IA) after first surgeries. Four patients required second surgeries, with two achieving seizure-freedom. Intraoperative MRI (iMRI) is beneficial. All nine corpus callosotomy patients (100%) achieved greater than 50% decrease in drop attacks. Number of antiepileptic drugs was weaned for 21/32 (66%) patients. Post-operative complications were low and some patients had anticipated neurological deficits. Outcomes were comparable to current literature. Conclusions: In well-selected candidates with tailored evaluation, paediatric epilepsy surgery is a safe therapeutic option with favourable outcomes and can be performed across the entire paediatric age range.

OBJECTIVE Several small series have described stereotactic MRI-guided laser interstitial thermal therapy for partial callosotomy of astatic and generalized tonic-clonic (GTC) seizures, especially in association with Lennox-Gastaut syndrome. Larger case series and comparison of distinct stereotactic methods for stereotactic laser corpus callosotomy (SLCC), however, are currently lacking. The objective of this study was to report seizure outcomes in a series of adult patients with epilepsy following anterior, posterior, and complete SLCC procedures and to compare the results achieved with a frameless stereotactic surgical robot versus direct MRI guidance frames. METHODS The authors retrospectively reviewed sequential adult epilepsy surgery patients who underwent SLCC procedures at a single institution. They describe workflows, stereotactic errors, percentage disconnection, hospitalization durations, adverse events, and seizure outcomes after performing anterior, posterior, and complete SLCC procedures using a frameless stereotactic surgical robot versus direct MRI guidance platforms. RESULTS Thirteen patients underwent 15 SLCC procedures. The median age at surgery was 29 years (range 20–49 years), the median duration of epilepsy was 21 years (range 9–48 years), and median postablation follow-up was 20 months (range 4–44 months). Ten patients underwent anterior SLCC with a median 73% (range 33%–80%) midsagittal length of callosum acutely ablated. Following anterior SLCC, 6 of 10 patients achieved meaningful (> 50%) reduction of target seizures. Four patients underwent posterior (completion) SLCC following prior anterior callosotomy, and 1 patient underwent complete SLCC as a single procedure; 3 of these 5 patients experienced meaningful reduction of target seizures. Overall, 8 of 10 patients in whom astatic seizures were targeted and treated by anterior and/or posterior SLCC experienced meaningful improvement. SLCC procedures with direct MRI guidance (n = 7) versus a frameless surgical robot (n = 8) yielded median radial accuracies of 1.1 mm (range 0.2–2.0 mm) versus 2.4 mm (range 0.6–6.1 mm; p = 0.0011). The most serious adverse event was a clinically significant intraparenchymal hemorrhage in a patient who underwent the robotic technique. CONCLUSIONS This is the largest reported series of SLCC for epilepsy to date. SLCC provides seizure outcomes comparable to open surgery outcomes reported in the literature. Direct MRI guidance is more accurate, which has the potential to reduce the risks of SLCC. Methodological advancements and larger studies are needed.

Background: Corpus callosotomy for medically intractable epilepsy is an effective ablative procedure traditionally achieved using either standard open craniotomy or with less-invasive approaches. Advances in robotic-assisted stereotactic guidance for neurosurgery can be applied for LITT for corpus callosotomy. Clinical Presentations: Two patients were included in this study. One was a 25-year-old female patient with extensive bi-hemispheric malformations of cortical development and medically refractory epilepsy, and the other was an 18-year-old male with medically refractory epilepsy and atonic seizures, who underwent a complete corpus callosotomy using robotic-assisted stereotactic guidance for LITT. Results: Both patients underwent successful intended corpus callosotomy with volumetric analysis demonstrating a length disconnection of 74% and a volume disconnection of 55% for patient 1 and a length disconnection of 83% and a volume disconnection of 33% for patient 2. Postoperatively, both patients had clinical reductions in seizure. Conclusion: Our experience demonstrates that robotic guidance systems can safely and effectively be adapted for minimally invasive LITT corpus callosotomy.

Epilepsy in children continues to present a major medical and economic burden on society. Left untreated, seizures can present the risk of sudden death and severe cognitive impairment. It is understood that primary care providers having concerns about abnormal movements or behaviors in children will make a prompt referral to a trusted pediatric neurologist. The authors present a brief introduction to seizure types, classification, and management with particular focus on what surgery for epilepsy can offer. Improved seizure control and its attendant improvements in quality of life can be achieved with timely referral and intervention.

Objective Patients with pathogenic cyclin-dependent kinase-like-5 gene (CDKL5) variants are designated CDKL5 deficiency disorder (CDD). This study aimed to delineate the clinical characteristics of Japanese patients with CDD and elucidate possible appropriate treatments. Methods We recruited patients with pathogenic or likely pathogenic CDKL5 variants from a cohort of approximately 1,100 Japanese patients with developmental and epileptic encephalopathies, who underwent genetic analysis. We retrospectively reviewed clinical, electroencephalogram, neuroimaging, and genetic information. Results We identified 29 patients (21 females, eight males). All patients showed severe developmental delay, especially in males. Involuntary movements were observed in 15 patients. No antiepileptic drugs (AEDs) achieved seizure freedom by monotherapy. AEDs achieving ≥ 50% reduction in seizure frequency were sodium valproate in two patients, vigabatrin in one, and lamotrigine in one. Seizure aggravation was observed during the use of lamotrigine, potassium bromide, and levetiracetam. Adrenocorticotrophic hormone (ACTH) was the most effective treatment. The ketogenic diet (KD), corpus callosotomy and vagus nerve stimulation did not improve seizure frequency in most patients, but KD was remarkably effective in one. The degree of brain atrophy on magnetic resonance imaging (MRI) reflected disease severity. Compared with females, males had lower levels of attained motor development and more severe cerebral atrophy on MRI. Conclusion Our patients showed more severe global developmental delay than those in previous studies and had intractable epilepsy, likely because previous studies had lower numbers of males. Further studies are needed to investigate appropriate therapy for CDD, such as AED polytherapy or combination treatment involving ACTH, KD, and AEDs.

OBJECTIVE Corpus callosotomy remains an established surgical treatment for certain types of medically refractory epilepsy in pediatric patients. While the traditional surgical approach is often well tolerated, the advent of MR-guided laser interstitial thermal therapy (LITT) provides a new opportunity to ablate the callosal body in a minimally invasive fashion and minimize the risks associated with an open interhemispheric approach. However, the literature is sparse regarding the comparative efficacy and safety profiles of open corpus callosotomy (OCC) and LITT callosotomy. To this end, the authors present a novel retrospective analysis comparing the efficacy and safety of these methods. METHODS Patients who underwent OCC and LITT callosotomy during the period from 2005 to 2018 were included in a single-center retrospective analysis. Patient demographic and procedural variables were collected, including length of stay, procedural blood loss, corticosteroid requirements, postsurgical complications, and postoperative disposition. Pre- and postoperative seizure frequency (according to seizure type) were recorded. RESULTS In total, 19 patients, who underwent 24 interventions (16 OCC and 8 LITT), were included in the analysis. The mean follow-up durations for the OCC and LITT cohorts were 83.5 months and 12.3 months, respectively. Both groups experienced reduced frequencies of seizure and drop attack frequency postoperatively. Additionally, LITT callosotomy was associated with a significant decrease in estimated blood loss and decreased length of pediatric ICU stay, with a trend of shorter length of hospitalization. CONCLUSIONS Longer-term follow-up and a larger population are required to further delineate the comparative efficacies of LITT callosotomy and OCC for the treatment of pediatric medically refractory epilepsy. However, the authors’ data demonstrate that LITT shows promise as a safe and effective alternative to OCC.

Lennox-Gastaut syndrome (LGS) is a severe form of childhood onset epilepsy in which patients require multiple medications and may be candidates for palliative surgical intervention. In this meta-analysis, we sought to evaluate the impact of palliative vagus nerve stimulation (VNS), corpus callosotomy (CC), and resective surgery (RS) by analyzing their impact on seizure control, antiepileptic drug (AED) usage, quality of life (QOL), behavior, cognition, prognostic factors, and complications. A systematic search of PubMed MEDLINE, Scopus, and Cochrane Database of Systematic Reviews was performed to find articles that met the following criteria: (1) prospective/retrospective study with original data, (2) at least one LGS surgery patient aged less than 18 years, and (3) information on seizure frequency reduction (measured as percentage, Engel class, or qualitative comment). Seizures were analyzed quantitatively in a meta-analysis of proportions and a random-effects model, whereas other outcomes were analyzed qualitatively. Forty studies with 892 LGS patients met the selection criteria, with 19 reporting on CC, 17 on VNS, four on RS, two on RS + CC, one on CC + VNS, and one on deep brain stimulation. CC seizure reduction rate was 74.1% (95% confidence interval [CI] = 64.5%-83.7%), and VNS was 54.6% (95% CI = 42.9%-66.3%), which was significantly different (p < .001). RS seizure reduction was 88.9% (95% CI = 66.1%-99.7%). Many VNS patients reported alertness improvements, and most had no major complications. VNS was most effective for atonic/tonic seizures; higher stimulation settings correlated with better outcomes. CC patients reported moderate cognitive and QOL improvements; disconnection syndrome, transient weakness, and respiratory complications were noted. Greater callosotomy extent correlated with better outcomes. AED usage most often did not change after surgery. RS showed considerable QOL improvements for patients with localized seizure foci. In the reported literature, CC appeared to be more effective than VNS for seizure reduction. VNS may provide a similar or higher level of QOL improvement with lower aggregate risk of complications. Patient selection, anatomy, and seizure type will inform decision-making.

Introduction An alteration in postoperative cognitive function varies according to the patients’ background characteristics, such as etiology, focus, and seizure duration. Accurate prediction and assessment of postoperative cognitive function is difficult in each patient. Adaptive behavior could describe the typical performance of daily activities and represents the ability to translate cognitive potential into real-world skills. We examined the relationship between alterations of executive function (EF) and adaptive behavior in school children undergoing surgery for intractable epilepsy. Methodology We enrolled 31 children with focal resection or corpus callosotomy for intractable epilepsy [mean age at surgery, 12.5 years; 16 boys; mean intellectual quotient, 73.3]. We surveyed answered questionnaires on attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and adaptive behavior using the Vineland Adaptive Behavior Scale, 2nd edition (VABS-II), and performed continuous performance tests (CPTs) on children pre- and postoperatively. Result ADHD and ASD symptoms improved after epilepsy surgery. The omission error (OE) in the CPT variable improved after epilepsy surgery, especially in children with a shorter preoperative period. Improved ASD symptoms led to an increased score of the coping skills subdomain. The reduced OE observed after surgery also increased the score of the community skills subdomain. Conclusion Improvement in EF and ASD symptoms resulted in better adaptive behavior postoperatively. These results were important for the pre- and postoperative evaluation and re-evaluation of children with epilepsy requiring special education and related services.

Intractable epilepsy impacts many children. Surgically resective and palliative treatments have developed to increase seizure freedom or palliate the seizure burden in those with medically refractory epilepsy. However, surgical epilepsy treatment can confer significant morbidity and death. Endoscope-assisted surgical approaches may be helpful in reducing the morbidity related to traditional open surgical approaches while allowing for good visualization of surgical targets. Here, the authors report a case utilizing an endoscope-assisted keyhole approach to perform a posterior quadrantectomy and corpus callosotomy, achieving the surgical goals of disconnection and reducing the need for large craniotomy exposure. They present the case of a 17-year-old male with medically refractory epilepsy treated with endoscope-assisted posterior quadrantectomy and corpus callosotomy through two mini-craniotomies to achieve a functional disconnection. To the authors’ knowledge, this is the first reported case of an endoscope-assisted approach for a posterior quadrantectomy for surgical epilepsy treatment in an adult or a pediatric patient. The case is reported to highlight the technical nuances and benefits of this approach in select patients as well as the expansion of applications of endoscope-assisted epilepsy surgery.

Lennox-Gastaut syndrome (LGS), a childhood-onset severe developmental and epileptic encephalopathy (DEE), is an entity that encompasses a heterogenous group of aetiologies, with no single genetic cause. It is characterised by multiple seizure types, an abnormal EEG with generalised slow spike and wave discharges and cognitive impairment, associated with high morbidity and profound effects on the quality of life of patients and their families. Drug-refractory seizures are a hallmark and treatment is further complicated by its multiple morbidities, which evolve over the patient's lifetime. This review provides a comprehensive overview of the current and future options for the treatment of seizures associated with LGS. Six treatments are specifically indicated as adjunct therapies for the treatment of seizures associated with LGS in the US: lamotrigine, clobazam, rufinamide, topiramate, felbamate and most recently cannabidiol. These therapies have demonstrated reductions in drop seizures in 15%-68% of patients across trials, with responder rates (≥ 50% reduction in drop seizures) of 37%-78%. Valproate is still the preferred first-line treatment, generally in combination with lamotrigine or clobazam. Other treatments frequently used off-label include the broad spectrum anti-epileptic drugs (AED) levetiracetam, zonisamide and perampanel, while recent evidence from observational studies has indicated that a newer AED, the levetiracetam analogue brivaracetam, may be effective and well tolerated in LGS patients. Other treatments in clinical development include fenfluramine in late phase III, perampanel, soticlestat-OV953/TAK-953, carisbamate and ganaxolone. Non-pharmacologic interventions include the ketogenic diet, vagus nerve stimulation and surgical interventions; these are also expanding, with the potential for less invasive techniques for corpus callosotomy that have promise for reducing complications. However, despite these advancements, patients continue to experience a significant burden. Because LGS is not a single entity, tailoring of treatment is needed as opposed to a 'one size fits all' approach. Further research is needed into the underlying aetiologies and pathophysiology of LGS, together with advancements in treatments that encompass the spectrum of seizures associated with this complex syndrome.

OBJECTIVECorpus callosotomy is a palliative procedure that is effective at reducing seizure burden in patients with medically refractory epilepsy. The procedure is traditionally performed via open craniotomy with interhemispheric microdissection to divide the corpus callosum. Concerns for morbidity associated with craniotomy can be a deterrent to patients, families, and referring physicians for surgical treatment of epilepsy. Laser interstitial thermal therapy (LITT) is a less invasive procedure that has been widely adopted in neurosurgery for the treatment of tumors. In this study, the authors investigated LITT as a less invasive approach for corpus callosotomy.METHODSThe authors retrospectively reviewed all patients treated for medically refractory epilepsy by corpus callosotomy, either partial or completion, with LITT. Chart records were analyzed to summarize procedural metrics, length of stay, adverse events, seizure outcomes, and time to follow-up. In select cases, resting-state functional MRI was performed to qualitatively support effective functional disconnection of the cerebral hemispheres.RESULTSTen patients underwent 11 LITT procedures. Five patients received an anterior two-thirds LITT callosotomy as their first procedure. One patient returned after LITT partial callosotomy for completion of callosotomy by LITT. The median hospital stay was 2 days (IQR 1.5–3 days), and the mean follow-up time was 1.0 year (range 1 month to 2.86 years). Functional outcomes are similar to those of open callosotomy, with the greatest effect in patients with a significant component of drop attacks in their seizure semiology. One patient achieved an Engel class II outcome after anterior two-thirds callosotomy resulting in only rare seizures at the 18-month follow-up. Four others were in Engel class III and 5 were Engel class IV. Hemorrhage occurred in 1 patient at the time of removal of the laser fiber, which was placed through the bone flap of a prior open partial callosotomy.CONCLUSIONSLITT appears to be a safe and effective means for performing corpus callosotomy. Additional data are needed to confirm equipoise between open craniotomy and LITT for corpus callosotomy.

Background: Anterior Corpus Callosotomy is a palliative treatment for drug-resistant generalized or multifocal epilepsy patients where focus excision is not an option for management. Callosotomy prevents propagation of epileptic discharge from one cerebral hemisphere to the other. Objective: To describe Al-Azhar University Hospitals experience and clinical outcome of Anterior Corpus Callosotomy for management of drug-resistant generalized epilepsy patients as an inexpensive palliative method. Patients and Methods: In this study, there are 15 patients admitted to Neurosurgery Department in Al-Azhar University Hospitals with drug-resistant generalized epilepsy. These patients were not candidates for lesionectomy. They were managed by anterior two thirds Corpus Callosotomy between February 2017 and December 2019. They were followed at outpatient clinic for at least 14 months. Clinical outcome regarding seizure control was assessed using Engel classification. Results: All 15 patients in this study underwent anterior two thirds corpus callosotomy and followed for at least 14 months. The post-operative improvement of seizure frequency has been evaluated using Engel outcome scale with 12 patients (80%) of the patients becoming Engel class II and 3 patients (20%) becoming Engel class III. Only 3 patients (20%) had minor transient postoperative complications; one patient (6.67%) had contra-lateral lower limb heaviness Grade 4 which was transient, one patient (6.67%) had contra-lateral lower limb Jacksonian focal fits and one patient (6.67%) had behavioral changes for one month. Conclusion: Corpus callosotomy is a palliative procedure and inexpensive method for management of patients with intractable focal with generalization and generalized drug-resistant epilepsy who are not suitable for resective surgery and with good outcome.

Background Microsurgical callosotomy is a procedure still under debate and to best a palliative treatment for drug-resistant epilepsy. Unlike microsurgery, radiosurgical callosotomy is an underpracticed treatment option, with no definite account of its safety and outcome profile. Objective To evaluate the safety, efficacy, and complication profile of radiosurgical callosotomy in the literature. Methods PubMed, SCOPUS, Web of Science, and ResearchGate were reviewed for radiosurgery and callosotomy in the English language following PRISMA guidelines. The patient profile, radiosurgical parameters (dose and isodose), target volume, extent of radiosurgery (anterior third, half, or posterior third callosotomy), and seizure outcome were evaluated. We evaluated the role of radiosurgery as a primary or secondary treatment modality after microsurgery. A literature review was performed to identify the evidence of radiosurgery. Results We identified 7 studies detailing 12 patients of mean age 22.8 years (range, 4–58 years) and a mean of 18.9 years of illness (range, 5–37 years). Five series performed Gamma Knife radiosurgery and 2 performed LINAC radiosurgery. The spectrum of seizures ranged from atonic seizures/drop attack (83%), generalized tonic-clonic seizures (75%), complex partial seizures (67%), absence seizures (50%), myoclonic seizures (33%), to focal seizures (16%). Four patients suffered from Lennox-Gastaut syndrome. The average seizure frequency in 11 patients was 297/month (range, 20/day to 15/month). Three patients became free of drop attacks and 2 free of generalized tonic-clonic seizures, and 1 became completely seizure free. The remaining patients continued to have seizures, albeit at a lower frequency. Complex partial seizures and myoclonic seizures were the least responsive seizure types to radiosurgical corpus callosotomy. All patients tolerated the procedure well. After radiosurgery, 3 patients developed symptomatic edema. The symptoms (headache, nausea, hemiparesis, and transient neurologic deficits) were controlled with a short course of steroids. Two patients needed redo radiosurgery (at the same target in 1 patient and complementary middle third callosotomy to previous anterior third callosotomy in another patient). There were no long-term complications. Conclusions Radiosurgery is a viable alternative to microsurgical callosotomy both as a primary and as a secondary treatment modality. It has a specific advantage of better neuropsychological outcomes with comparable seizure control. The neurosurgical community should adopt a more liberal approach with this indication.

Magnetic resonance imaging–guided laser-induced thermal therapy (MRgLITT) is a minimally invasive surgical approach increasingly employed for precise targeted ablation of epileptogenic brain foci. Recent reports have described corpus callosotomy using MRgLITT, though its application in more extensive functional disconnections has not been documented. Here, the authors detail its use in achieving a palliative hemispherotomy in a 5-year-old with medically refractory hemiclonic seizures following a hemispheric infarction, highlighting a novel use of this surgical technique. In this particular case, open craniotomy was deemed high risk given the multiple medical comorbidities including congenital cardiac disease and end-stage renal failure. MRgLITT was considered an alternative approach with a lower risk for periprocedural hemodynamic perturbations. The patient tolerated the procedure well, attaining an Engel class IB outcome at 16 months’ follow-up. This suggests that MRgLITT may be an alternative approach to an open hemispherectomy, particularly in cases in which multiple comorbidities pose significant risks and preclude an open procedure.

Background The corpus callosotomy (CCT) has been reported as an effective procedure to alleviate drop attacks. However, the extent of CCT remains debatable. Classical studies suggest that motor fibers traverse mainly through the anterior half of the corpus callosum (CC), although recent diffusion tensor imaging studies described that motor fibers crossed the CC in a more posterior location, emphasizing the posterior midbody and the isthmus. Methods Cortical and subcortical structures were examined in 30 hemispheres prepared for white matter fiber dissection. Dissections were carried out under surgical magnification to trace fibers originating from the primary motor cortex and their course through the CC. The distance of the most anterior and posterior motor fibers to the tip of the genu were measured, and the extent of CCT enabling disconnection of all motor fibers was calculated. Results Motor fibers coursed through the posterior half of the CC in the majority of hemispheres, mainly locating in posterior midbody and the isthmus. Callosal fibers should be interrupted to an average of 61% ± 0.07% point of the CC to reach the anterior limit of motor fibers and to an average of 69% ± 0.07% point to include posterior limit of motor fibers. Motor fibers were extending until the posterior one third of the CC in 22 specimens. Conclusions Anterior-half CCT did not include all motor fibers in any specimen. Anterior two thirds CCT disrupted all motor fibers in one fourth of the cases. Our findings suggest that an ideal CCT should extend to the posterior midbody and isthmus of the CC.

Background Stereotactic radiosurgery (SRS) offers a noninvasive technique for division of the corpus callosum, which can confer improved seizure control to patients suffering from frequent atonic seizures due to rapid interhemispheric generalization. This noninvasive approach is well-suited for use in a palliative intervention for improved seizure control in this patient population. To our knowledge, this is the first report of radiosurgical completion corpus callosotomy in an adult in the United States. Case Description A 20-year-old ambidextrous nonverbal man with a history of refractory generalized epilepsy status post open anterior corpus callosotomy at age 10 years, Lennox-Gastaut syndrome, and autism presented after 2 years of incremental, progressive deterioration in seizure control and behavior including 1 year. The family decided to pursue SRS corpus callosotomy. Under general anesthesia, a volume of interest encompassing a full midsagittal plane of the corpus callosum was defined to deliver 60 Gy to the 50% isodose line fully encompassing the target. Gamma Knife was used with 2 isocenters at 90° and 1 at 110° and isodose lines of 60, 20, and 12 Gy. Treatment was carried out without difficulty or complications while the patient remained under close monitoring. The patient was discharged the next day with a 2-week taper of dexamethasone. Conclusions Eight months postradiosurgical corpus callosotomy, the patient is free of atonic seizures and is ambulatory. In carefully selected cases and with protective radiosurgical planning, SRS for completion corpus callosotomy represents an effective option for refractory seizure control.

Anterior callosotomy to about 20 mm has been considered relatively safe empirically. The present study aimed to compare cognitive function before and after resection of tumors in the anterior part of the lateral ventricle. We analyzed 6 patients with intraventricular tumors located in the anterior horn or body of the lateral ventricle who underwent surgical excision via interhemispheric transcallosal approach at Osaka City University Hospital between March 2015 and August 2018. And clinical and imaging studies, neuropsychological function using MMSE, WAIS-III and WMS-R and surgical complications were retrospectively reviewed based on the medical records at our institution. As a result, 4 patients achieved gross total resection of the tumor and 2 patients achieved subtotal resection. 4 patients showed hydrocephalus, which disappeared in each case within 6 months after tumor resection. Mean length of callosotomy was 16.9 mm (range, 15.5–26.1 mm). One patient showed postoperative transient deficits including aphasia, microphonia, ballism in all extremities and hemiplegia, and another patient experienced subjective difficulty when talking. These symptoms disappeared within 3 months after tumor resection. Scores from the MMSE and WAIS-III showed no significant postoperative deterioration. Performance intelligence quotient (P = 0.04), full intelligence quotient (P = 0.04) and perceptual organization (P = 0.03) of WAIS-III were significantly improved after surgery compared with preoperatively. In conclusion, anterior corpus callosotomy of about 20 mm for intraventricular tumor in the anterior horn or body of the lateral ventricle might have little effect on cognitive function in the chronic phase, although the influence of hydrocephalus cannot be ignored.

Atonic seizures are associated with a particularly poor response to medical treatment. We performed a systematic review and meta-analysis to compare the efficacy of corpus callosotomy (CC) and vagus nerve stimulation (VNS) in the management of atonic seizures in the pediatric population. A literature search was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and recommendations, focusing on atonic seizures, CC, and VNS in pediatric populations. Pertinent clinical data were extracted and analyzed. Pooled effects between groups were calculated as standardized error (SE) with 95% confidence intervals (CIs). To assess for statistical significance, the Z-test was performed, using the pooled effect size (ES) and 95% CI for each intervention. A total of 31 studies met the inclusion criteria, with 24 studies encompassing 425 children treated with CC and 7 studies encompassing 108 children treated with VNS. Twenty-four studies were included in a meta-analysis. There was a statistically significant difference in the primary outcome of atonic seizure control in favor of CC (overall effect size (ES) 0.73, 95% CI 0.69–0.77 for CC, ES 0.4, 95% CI 0.28–0.51 for VNS, p = 0.003). There was a higher rate of complications requiring reoperation in the CC cohort (6.6% vs. 3.8%) and a 14% rate of symptomatic disconnection syndrome. While both techniques are safe, CC provides a much higher chance of effectively managing this morbid seizure type albeit with a higher risk of re-operation and disconnection syndrome.

Corpus callosotomy is a palliative surgical option for patients with refractory epilepsy and frequent drop attacks, decreasing seizure frequency and severity by disconnecting the cerebral hemispheres. Though often successful, open surgery is not without risk. Corpus callosotomy by MRI-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to the standard open procedure. This report aims to present an illustrative case and systematically review the current literature on the surgical technique. A systematic review of the English literature through January 2019 was performed. Articles were searched by title utilizing the following key word combinations: “laser” and “callosotomy”, “callosotomy” and “ablation”, “laser” and “corpus”, “callosotomy” and “thermal”, and “stereotactic” and callosotomy”. The articles recovered were then classified by level of evidence and summarized. Fifteen papers were reviewed, of which 6 met inclusion and exclusion criteria. All included studies were classified as level IV evidence. There was a total of 13 patients ranging from 13 months to 44 years old (mean 23.5 years old). The number of laser fibers utilized ranged from 1 to 3. Engel class I was achieved in 5 patients, II in 4, III in 2, IV in 1. Reported patient follow up was 4–39.7 months (mean 15.43). Corpus callosotomy utilizing MRI-guided laser interstitial thermal therapy results in improvement in seizure frequency and severity with minimal complications. Prospective trials are needed to compare its seizure control and long-term outcomes to that of standard open callosotomy.

Objective Corpus callosotomy is an effective palliative treatment for drug-resistant Lennox-Gastaut syndrome (LGS). Laser interstitial thermal therapy has been increasingly used in the treatment of epilepsy. Here, we assess the safety and effectiveness of minimally invasive stereotactic laser anterior corpus callosotomy (SLACC) for drop attacks in LGS. Methods We reviewed sequential cases of patients with medically intractable LGS who underwent SLACC using a two-cannula technique between November 2014 and July 2019. Pre- and postoperative magnetic resonance imaging was used to measure the anteroposterior length of callosal ablation (contrast-enhancing lesion) and estimated disconnection (gap in tract projections on diffusion tensor imaging). Patients were followed longitudinally to assess clinical outcomes. Results Ten patients were included in this study. The median age was 33 (range = 11-52) years, median duration of epilepsy was 26 (range = 10-49) years, and median duration of postoperative follow-up was 19 (range = 6-40) months. In the anteroposterior direction, 53 ± 7% (mean ± SD) of the corpus callosum was ablated and 62 ± 19% of the corpus callosum was estimated to be disconnected. Six (60%) of 10 patients achieved >80% seizure reduction, two (20%) of whom became seizure-free. Eight (80%) patients had >80% reduction in drop attacks, five (50%) of whom became free of drop attacks. Three patients subsequently underwent laser posterior callosotomy with further improvement in drop attacks and/or overall seizure frequency. One patient had an asymptomatic intracerebral hemorrhage along the cannula tract. One patient developed significant aggression after becoming seizure-free. Significance Seizure outcomes following SLACC were comparable to previously reported outcomes of open callosotomy, with reasonable safety profile. SLACC appears to be an effective alternative to open anterior corpus callosotomy with minimal postoperative discomfort and a short recovery period.

Introduction Corpus callosotomy (CCT) is a palliative procedure to treat injurious drop attacks or multifocal/generalized seizures in which resection of the epileptogenic focus is not feasible. We are presenting our experience in treating intractable epilepsy patients by CCT procedures. Methods We observed 16 patients who underwent callosotomy (male to female ratio 7:9; adult to pediatric ratio 3:13). Initial seizure frequency was reported ranged from 1 to 2 attacks daily to very often (more than 20 episodes daily). Results Our observation showed that among patients with drop attacks, complete and >90% seizure freedom was reported by 4 and 6 of 13 patients, respectively (76.9% combined). Conclusion Our observation showed that corpus callosotomy yielded good outcome in patients with intractable epilepsy in Indonesia. Our observation showed total callosotomy achieved complete seizure freedom better compared to partial callosotomy patients.

Background For patients with focal drug-resistant epilepsy (DRE), surgical resection of the epileptogenic zone (EZ) may offer seizure freedom and benefits for quality of life. Yet, concerns remain regarding invasiveness, morbidity, and neurocognitive side effects. Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) has emerged as a less invasive option for stereotactic ablation rather than resection of the EZ. Objective To provide an introduction to MRgLITT for epilepsy, including historical development, surgical technique, and role in therapy. Methods The development of MRgLITT is briefly recounted. A systematic review identified reported techniques and indication-specific outcomes of MRgLITT for DRE in human studies regardless of sample size or follow-up duration. Potential advantages and disadvantages compared to available alternatives for each indication are assessed in an unstructured review. Results Techniques and outcomes are reported for mesial temporal lobe epilepsy, hypothalamic hamartoma, focal cortical dysplasia, nonlesional epilepsy, tuberous sclerosis, periventricular nodular heterotopia, cerebral cavernous malformations, poststroke epilepsy, temporal encephalocele, and corpus callosotomy. Conclusion MRgLITT offers access to foci virtually anywhere in the brain with minimal disruption of the overlying cortex and white matter, promising fewer neurological side effects and less surgical morbidity and pain. Compared to other ablative techniques, MRgLITT offers immediate, discrete lesions with real-time monitoring of temperature beyond the fiber tip for damage estimates and off-target injury prevention. Applications of MRgLITT for epilepsy are growing rapidly and, although more evidence of safety and efficacy is needed, there are potential advantages for some patients.

Background: Epilepsy is a disease of the brain defined by any of the following conditions: At least 2 unprovoked (or reflex) seizures occurring more than 24 hours apart; One unprovoked (or reflex) seizure with relatively high recurrence risk (i.e., ≥60% (, occurring over the next 10 years; or Diagnosis of an Epilepsy syndrome. Objectives: This work aims to review surgical outcome for drug resistant epilepsy of different causes to identify which patient would get the most benefit. Patients and Methods: Prospective and retrospective study on 20 cases with drug resistant epilepsy at Al-Azhar university hospitals.surgical techniques:Lesionectomy Surgery, corpus Callosotomy Conclusion: The objective of epilepsy surgery is complete seizure control without any resulting post-surgical functional deficits, so presurgical evaluation is to determine whether or not epilepsy surgery can be done and to define its chances of risk and benefit. Surgery can be classified to curative procedures which are performed when tests consistently point to a specific area of the brain where the seizures begin, as the Temporal lobectomy which is the most common type of surgery, Cortical excision, Hemispherectomy and Palliative procedures are performed when a specific area in the brain can’t be determined or when the seizure focus overlaps brain areas critical for movement as Vagus nerve stimulation. Not all people who have done epilepsy surgery are seizure free following surgery, but there is usually a significant decrease in seizures. Some people may have some seizures immediately after surgery but this doesn’t mean that the surgery wasn’t successful.

Background When the epileptogenic foci skip the motor area, the epilepsy can be cured by surgery while preserving the motor function. This surgery has been reported as subtotal hemispherectomy. The disconnective variant of this surgery, subtotal hemispherotomy, is described. Objective To demonstrate each step clearly, a cadaveric brain, 3-dimensional reconstruction and simulation model, and intraoperative photographs were used. Methods A formalin-fixed cadaveric brain was dissected to show each step of this surgery. For the 3-dimensional model, several brain structures were reconstructed from preoperative images, and the surgery was simulated. Intraoperative photographs and postoperative magnetic resonance images were taken from the representative cases. Results Temporo-parieto-occipital disconnection is performed to disconnect these lobes and the insula, limbic system, and splenium of the corpus callosum. The postcentral sulcus is the anterior border of the disconnection. Next, prefrontal disconnection is performed to disconnect the frontal lobe and the insula, frontal lobe and basal ganglia, and the anterior part of the corpus callosum. The precentral sulcus is the posterior border of the disconnection. Finally, corpus callosotomy of the central part is performed. After these steps, subtotal hemispherotomy, with preservation of the pre- and postcentral gyrus, is achieved. The 3-dimensional model clearly shows the anatomic relationships between deep brain structures. In the representative cases, postoperative motor deterioration was transient or none, and seizure-free status was achieved after surgery. Conclusion Subtotal hemispherotomy is generally difficult because of the complicated anatomy and narrow and deep surgical corridors. Combined use of these methods facilitates a clearer understanding of this surgery.

Introducción: Los pacientes con convulsiones intratables que no son candidatos para la cirugía de resección focal están indicados para un procedimiento quirúrgico paliativo, la callosotomía. Este procedimiento se basa en la hipótesis de que el cuerpo calloso es una importante vía para la propagación interhemisférica de la actividad epiléptica y, para la epilepsia resistente a fármacos. Presenta relativamente baja morbilidad permanente y una eficacia en el control de las convulsiones. Sobre la base de la literatura, la callostomía mejora la calidad de vida de los pacientes que tiene la indicación para realizar este procedimiento, ya que permite reducir la frecuencia de las crisis, ya sean tónica o átona, tónico-clónicas, ausencia o lóbulo frontal crisis parciales complejas. Objetivo: El objetivo de esta revisión de la literatura es discutir los detalles técnicos, modalidades, riesgos, complicaciones, resultados y de pronóstico de callosotomía basado en la revisión crítica de la literatura y la experiencia de los autores. Casuística y Métodos: Se realizó la consulta bibliográfica, utilizando la base de datos MEDLINE, LILACS, SciELO, que utiliza el lenguaje como criterios de selección, la elección de los artículos recientes preferiblemente en portugués, español o Inglés, con el año de publicación superior a 2000. Conclusión: De acuerdo con la experiencia y las referencias del autor, callosotomía es un procedimiento seguro cuando indicado para casos seleccionados y la tasa de éxito es proporcional a la extensión de la resección del cuerpo calloso. A mayor resección puede reducir la frecuencia de las crisis, sin embargo, la morbilidad puede ser también mayor. No hay ningún estudio que compara la estimulación del nervio vago frente a frente callosotomía VNS más callososotomy, lo que sería la futura necesaria para una importante fuente de datos sobre este tema.

OBJECTIVE Corpus callosotomy is a safe and effective procedure for reducing the frequency of drop attacks. MR-guided laser interstitial thermal therapy (MRgLITT) offers a minimally invasive alternative to conventional open craniotomy for callosotomy. We hypothesized that MRgLITT callosotomy could be safely performed in pediatric patients with similar seizure control. METHODS We present an institutional case series of 11 procedures in 10 patients for the treatment of drop attacks in drug-refractory primary generalized epilepsy. MRgLITT was used for complete callosotomy, anterior two-thirds, posterior, or ablation of residual callosal fibers following prior callosotomy (open or MRgLITT). We retrospectively reviewed clinical course, operative details, radiographic imaging, clinical outcomes, and complications. RESULTS Operative time ranged from 4-8 hours, and median hospitalization was 2 days. No complications were encountered. Among the 7 patients with at least 3 months of follow-up, 71% experienced freedom from drop attacks at longest follow-up and 57% of cases showed improvement in their other seizure semiologies as well (Engel Class II: 28%, Class III: 28%, Class IV: 43%). SIGNIFICANCE MR-guided LITT callosotomy is safe and effective modality in the management of pediatric patients with medically intractable epilepsy characterized by drop attacks. While this is among the largest pediatric series to date, further studies are required to delineate its safety and efficacy among such patients.

Herpes simplex virus (HSV) is a neurotropic pathogen that can invade, replicate, establish latency, and reactivate within the CNS.1 Potential triggers of reactivation include immunosuppression, fever, and direct insult.1–3 HSV reactivation may cause recurrence of an infectious process, herpes simplex encephalitis (HSE), or recurrence of a relatively benign condition, Mollaret meningitis. Here we report the case of a patient with intractable epilepsy following a febrile illness at age 2 thought to be secondary to HSV. She ultimately underwent an anterior corpus callosotomy 2 decades later with a postoperative course complicated by HSV reactivation. Whereas the majority of cases of HSV reactivation occur within the first year of illness, it is important to recognize that this virus may remain dormant for years and later reactivate in the setting of physiologic stress.

A 2-month-old, intact male domestic shorthair cat with dullness, bilateral central blindness, and recurrent epileptic seizures was presented to a local clinic. Seizures were the generalized myoclonic and tonic-clonic type. Phenobarbital was initiated and maintained; however, seizures were not controlled. Other anti-seizure drugs, including levetiracetam, zonisamide, and diazepam, also provided insufficient seizure control with seizures occurring hourly to daily. By 8 months of age, the cat displayed non-ambulatory tetraparesis and deep somnolence. Magnetic resonance imaging (MRI), cerebrospinal fluid analysis, and pre- and post-prandial total bile acid analyses were unremarkable. Scalp electroencephalography (EEG) revealed central dominant but generally synchronized spikes and multiple spikes. The cat was diagnosed with drug-resistant epilepsy of unknown cause and was included in a clinical trial of epilepsy surgery. Given the unremarkable MRI and bilateral synchronized EEG abnormalities, a corpus callosotomy was performed at 12 months of age, and partial desynchronization of spikes was confirmed on EEG. Incomplete transection was found in the genu of the corpus callosum on postoperative MRI. After surgery, the mental status and ambulation clearly improved, and seizure frequency and duration were remarkably reduced. Recheck with follow-up EEG and MRI were performed at 3, 6, and 12 months after surgery. Scores of activities of daily living and visual analog scales including cat's and owner's quality of life had also improved considerably. This case report is the first documentation of the one-year clinical outcome of corpus callosotomy in a clinical feline case with drug-resistant epilepsy.

Magnetic resonance-guided laser interstitial thermal therapy (MR-gLiTT) is a novel minimally invasive treatment approach for drug-resistant focal epilepsy and brain tumors. Using thermal ablation induced by a laser diode implanted intracranially in a stereotactic manner, the technique is highly effective and safe, reducing the risk associated with more traditional open surgical approaches that could lead to increased neurological morbidity. Indications for MR-gLiTT in pediatric epilepsy surgery include hypothalamic hamartoma, tuberous sclerosis complex, cavernoma-related epilepsy, SEEG-guided seizure onset zone ablation, corpus callosotomy, periventricular nodular heterotopia, mesial temporal lobe epilepsy, and insular epilepsy. We review the available literature on the topic and present our series of patients with drug-resistant epilepsy treated by MR-gLiTT. Our experience, represented by six cases of hypothalamic hamartomas, one case of tuberous sclerosis, and one case of dysembryoplastic neuroepithelial tumor, helps to confirm that MR-gLiTT is a highly safe and effective procedure for several epilepsy conditions in children.

Surgical treatment of epilepsy typically focuses on identification of a seizure focus with subsequent resection and/or disconnection to "cure" the patient's epilepsy and achieve seizure freedom. Palliative epilepsy surgery modalities are efficacious in improving seizure frequency, severity, and quality of life. In this paper, we review palliative epilepsy surgical options for children: vagus nerve stimulation, responsive neurostimulation, deep brain stimulation, hemispherotomy, corpus callosotomy, lobectomy and/or lesionectomy and multiple subpial transection. Reoperation after surgical resection should also be considered. If curative resection is not a viable option for seizure freedom, these methods should be considered with equal emphasis and urgency in the treatment of drug-resistant epilepsy.

To study surgical outcomes in pharmaco-resistant epilepsy associated with posterior cortex ulegyria secondary to perinatal insults.A cohort was analysed for clinico-radiological charectaristics, surgical interventions and seizure outcomes.A total of 38 patients underwent surgery, divided as group A - curative surgeries (n = 20) and group B - palliative surgeries (n = 18). Mean age of onset of epilepsy in group A was 5.2 ± 3.4 years against 2.7 ± 2.4 years in group B (p 0.01). Electroclinical Lennox Gastaut Syndrome was encountered in 9/20 patients in group A, against all 18 patients in group B. Disabling reflex epilepsy was seen in 10 (26 %) patients. Interictal electrophysiology localized in the posterior cortex in all patients in group A, but ictal onsets contributed in only 7/20 patients. Nine patients from group A had unilateral parieto-occipital ulegyria while bilateral in 11/20 patients, and 16/18 from group B. Group A patients underwent parieto-occipital resection (n = 10) and temporo-parieto-occipital disconnection (n = 10) while group B underwent complete corpus callosotomy (n = 18). In group A, Engel Ia outcome was achieved in 15/20 patients (75 %) at mean follow up of 23.5 ± 7.9 months. Group B patients experienced cessation of head drops in all 18 patients, with two-third reduction in seizure frequency at 29.2± 12.4 months of mean follow up. Reflex seizures responded completely in both groups.Epilepsy surgeries for posterior cortex ulegyria results in excellent seizure outcomes. Corpus callosotomy appears highly effective as a palliation for head drop as well as disabling reflex seizures in a well selected cohort.

Objective We analyzed the features of fast oscillations (FOs) and connectivity in hypsarrhythmia to identify biomarkers for predicting seizure outcomes after total corpus callosotomy (TCC) in children with pharmacoresistant infantile spasms (IS). We hypothesize that the power of FOs and connectivity of slow waves in hypsarrhythmia would indicate the prognosis of IS. Method We retrospectively identified 42 children with pharmacoresistant IS who underwent TCC from 2009 to 2014 at Nagasaki Medical Center. We collected preoperative hypsarrhythmia for 200 seconds from each child. Children were categorized into three groups with interictal epileptic discharges on EEG at 6 months after TCC: group A, no epileptic discharge; group B, lateralized epileptic discharges; and group C; bilateral epileptic discharges. We analyzed spectral power and phase synchronization in preoperative hypsarrhythmia among the three groups. Results We found 10 children in group A, 10 children in group B, and 22 children in group C. All group A and 1 in group B achieved seizure freedom after TCC. Six (67%) of 9 group B children who underwent further surgeries achieved seizure freedom. Ten (45%) of group C children had seizure reduction >50% after TCC, and 13 (87%) of 15 children who underwent further surgeries had residual seizures. The clinical profiles of the three groups did not differ significantly. The power of FOs (≥45 Hz) in hypsarrhythmia was significantly stronger in group C at the midline and temporal regions than in groups B and A (P = .014). The connectivity of theta (4-9 Hz) and FOs (29-70 Hz) tended to increase in group C, compared with the increased connectivity of 1-2 Hz in group A (P = .08). Significance The increased power and connectivity of FOs in hypsarrhythmia may correlate with pharmacoresistant and surgically resistant seizures in IS. The existence and connectivity of FOs are associated with unilateral/bilateral cortical epileptogenicity in hypsarrhythmia. Prominent slow waves and connectivity without FOs might correlate with seizure freedom after TCC. Modulation of the callosal system with subcortical/cortical epileptic discharges might play a role in generating hypsarrhythmia and IS.

Background Progressive myoclonic epilepsy (PME) is a syndrome characterized by development of progressive myoclonus, cognitive impairment, and other neurologic deficits. Despite major advances in medical treatment of epilepsy, some PME patients remain refractory to antiepileptic drugs. This may further accentuate cognitive impairment and deteriorate functional capacity. Corpus callosotomy (CC) is used in patients with drug-resistant epilepsy who are not candidates for either excisional epilepsy surgery or neurostimulation. We report the application of the standard complete callosotomy to control medically refractory status epilepticus in a patient with PME. Case Description A 16-year-old boy was referred to the emergency department with generalized tonic-clonic seizures. He was known to have PME since 5 years earlier, with frequent generalized seizures requiring hospitalization and reloading of the drugs. The patient was discussed by the epilepsy surgery working group, and corpus callosotomy was considered as a last resort to control the refractory status epilepticus. The patient experienced no generalized seizures during the 3-month postoperative period (Engel class IIIB). Conclusions Inasmuch as surgery was the last resort to control severe disabling status epilepticus, because most of the epileptogenic discharges were originating from the parieto-occipital regions and profound cognitive impairment was present, we decided to perform a complete rather than just an anterior callosotomy. CC may be considered to prevent secondary generalized seizures as the most disabling attacks in patients with certain epilepsy syndromes. Nevertheless, the impact of palliative surgical intervention on the overall disease course of patients with an underlying diffuse pathologic state remains to be determined.

Corpus callosotomy has been used as a form of surgical palliation for patients suffering from medically refractory generalized seizures, including drop attacks. Callosotomy has traditionally been described as involving a craniotomy with microdissection. MR-guided laser interstitial thermal therapy (MRg-LITT) has recently been used as a minimally invasive method for performing surgical ablation of epileptogenic foci and corpus callosotomy. The authors present 3 cases in which MRg-LITT was used to perform a corpus callosotomy as part of a staged surgical procedure for a patient with multiple seizure types and in instances when further ablation of residual corpus callosum is necessary after a prior open surgical procedure. To the authors’ knowledge, this is the first case series of corpus callosotomy performed using the MRg-LITT system with a 3.3-year average follow-up. Although MRg-LITT is not expected to replace the traditional corpus callosotomy in all cases, it is a safe, effective, and durable alternative to the traditional open corpus callosotomy, particularly in the setting of a prior craniotomy.

Background Patients with MECP2 duplication syndrome present with distinct facial anomalies and clinical features such as global developmental delay, recurrent respiratory infections, and epileptic seizures. Approximately half of all patients develop epileptic seizures which are refractory in most cases despite active medical management. Furthermore, no previous reports have discussed the efficacy of surgical treatment for seizures in patients with MECP2 duplication syndrome. Case report In the present report, we describe a case of MECP2 duplication syndrome in a 15-year-old boy who developed epileptic seizures following influenza-associated acute encephalitis. His frequent epileptic spasms, tonic, atonic, and partial seizures were refractory to multiple antiepileptic medications. Electroencephalography revealed continuous diffuse epileptic discharge, resulting in regression. A total corpus callosotomy (CC) was performed at the age of 14 years and 7 months. His seizures markedly decreased following CC, although he continued to experience brief partial seizures approximately once per month. Post-operative examination revealed that his epileptic discharges had disappeared, and that his developmental state had returned to pre-encephalopathy levels. Conclusion Our findings indicate that CC may represent a valuable surgical option for children with medically refractory generalized seizures following acute encephalopathy, irrespective of genetic disorders such as MECP2 duplication syndrome.

Purpose To provide a descriptive analysis on the presurgical evaluation and surgical management of a cohort of patients with stroke related epilepsy (SRE). Methods We retrospectively examined the clinical characteristics, results of non-invasive and invasive presurgical evaluation, surgical management and outcome of consecutive patients with drug-resistant SRE in our institution from January 1, 2013 to January 1, 2020. Results Twenty-one of 420 patients (5%) who underwent intracranial EEG (iEEG), resective epilepsy surgery and/or vagus nerve stimulation (VNS) placement, had SRE. Of 13 patients who had iEEG, the ictal onset (IO) was exclusively within the stroke lesion in only one patient. In five patients the IO was extra-lesional and in the remaining seven patients it included the stroke lesion as well as extra-lesional structures. The IO included the mesial temporal region in 11 of the 13 patients (85%). The posterior margin of the stroke lesion was always involved. Five patients underwent surgery without iEEG. In total, 10 patients underwent resective surgery, four VNS placement and two had both corpus callosotomy and VNS placement. Of the patients who had resective surgery, nine were Engel I or II at last follow up. Conclusion We found that seizures in patients with drug resistant SRE were more frequently originated in the mesial temporal region than in the stroke lesion itself. Despite the complex epileptic network underlying drug-resistant SRE, a thorough presurgical assessment and adequate use of surgical options can lead to excellent surgical outcomes.

Background Alien hand syndrome (AHS) is a disabling condition in which one hand behaves in a way that the person finds "alien". This feeling of alienation is related to the occurrence of movements of the respective hand performed without or against conscious intention. Most information on AHS stems from single case observations in patients with frontal, callosal, or parietal brain damage. Methods Retrospective analysis of distinctive clinical features of three out of 18 epilepsy patients who developed AHS with antagonistic movements of the left hand after corpus callosotomy (CC) (one anterior, two complete) for the control of epileptic seizures, particularly epileptic drop attacks (EDA). Results Remarkably, these three patients, two men and one woman, displayed atypical language dominance with a bilateral, left more than right hemisphere language representation in intracarotidal amobarbital testing before surgery. The overall additional distinctive feature of the target patients was genuine left-handedness, with writing retrained to right-handedness in two patients. After surgery the left hands became alien. The problem was permanent, despite strategies for compensation. Conclusion From this observation we suggest that under the conditions of dissociation of language and motor dominance, loss of both intentional control of contralateral action and physiological inhibition of antagonistic movements lead to post-callosotomy alien-hand-like motor phenomena. The dissociation pattern posing this risk seems rare but needs to be considered when evaluating candidates for callosotomy.

Both corpus callosotomy (CC) and the ketogenic diet (KD) are commonly used in patients with Lennox Gastaut syndrome (LGS), as a significant proportion of these patients develop pharmacoresistant epilepsy. But no systematic review has yet compared the efficacy and safety of these two measures. We conducted a systematic search on various databases to collating all available literature until 30th November 2020 with a primary objective to compare the efficacy of KD and CC in terms of the proportion of patients with complete seizure freedom, at least 75% and 50% reduction in seizure frequency at various time points after the institution of these modalities. We also attempted to compare the proportion and nature of adverse effects, impact on EEG, cognition, and behavior with these modalities. We only included original articles enrolling at least 10 patients with CC or KD for quantitative synthesis to determine a pooled estimate. We used a fixed or random effects model, depending on the degree of heterogeneity. We selected 23 and 7 articles describing the efficacy of CC and KD in 436 and 185 LGS patients out of 217 search items, but none of the studies compared directly these two entities. The indirect comparison between the pooled estimate of all patients with individual modalities revealed more patients with CC had seizure freedom, at least 75% and 50% reduction in seizure frequency (p=0.0001, 0.01, and 0.04 respectively). The proportion of patients with adverse effects was also higher for CC patients (p=0.01), although the proportion with serious adverse effects was not significantly different between the two modalities. Patients selected for CC were older, had higher seizure burden, more lag time after the onset of seizures, and received more number of antiseizure medications previously. Due to the availability of limited data, a firm conclusion could not be determined regarding the effect on EEG, cognition, and behavior with CC and KD. CC is more efficacious than KD in reducing seizure frequency in patients with LGS, although it has relatively more adverse effects during the immediate perioperative period.

Objective: We aimed to clarify the patterns of ictal power and phase lag among bilateral hemispheres on scalp electroencephalography (EEG) recorded pre-operatively during epileptic spasms (ESs) and the correlation with the outcomes following corpus callosotomy.Methods: We enrolled 17 patients who underwent corpus callosotomy for ESs before 20 years of age. After corpus callosotomy, seven patients did not experience further ESs (favorable outcome group), and the remaining 10 patients had ongoing ESs (unfavorable outcome group). We used pre-operative scalp EEG data from monopolar montages using the average reference. The relative power spectrum (PS), ictal power laterality (IPL) among the hemispheres, and phase lag, calculated by the cross-power spectrum (CPS) among symmetrical electrodes (i.e., F3 and F4), were analyzed in the EEG data of ESs from 143 pre-operative scalp video-EEG records. Analyses were conducted separately in each frequency band from the delta, theta, alpha, beta, and gamma range. We compared the means of those data in each patient between favorable and unfavorable outcome groups.Results: Among all frequency bands, no significant differences were seen in the individual mean relative PSs in the favorable and unfavorable outcome group. Although the mean IPLs in each patient tended to be high in the unfavorable outcome group, no significant differences were found. The mean CPSs in the delta, theta, and gamma frequency bands were significantly higher in the unfavorable than in the favorable outcome group. Using the Youden index, the optimal cutoff points of those mean CPS values for unfavorable outcomes were 64.00 in the delta band (sensitivity: 100%, specificity: 80%), 74.20 in the theta band (100, 80%), and 82.05 in the gamma band (100, 80%). Subanalyses indicated that those CPS differences originated from pairs of symmetrical electrodes in the bilateral frontal and temporal areas.Significance: Ictal power and laterality of the ictal power in each frequency band were not associated with the outcomes of CC; however, the phase lags seen in the delta, theta, and gamma frequency bands were larger in the unfavorable than in the favorable outcome group. The phase lags may predict outcomes of CC for ESs on pre-surgical scalp-ictal EEGs.

The exoscope is a new form of optic device that has begun to be used in the last decade. The exoscope provides high-quality magnification and illumination at depth, allowing easy manipulation of surgical instruments even in narrow surgical fields. Exoscopic corpus callosotomy (CC) has not been reported. We report herein our initial experience with the utility of exoscopic CC. A 3-year-old boy diagnosed with West syndrome at 4 months old was referred to our hospital. As the seizure spasms were considered to carry a risk of severe traumatic injury, we performed exoscopic CC as palliative therapy. An EX VITOM 3D exoscope and 4K-3D surgical monitor were used during the procedure. No surgical complications that could be related to exoscope use were noted. Operative time for exoscopic CC was comparable to that for microscopic CC, despite a lack of previous experience with the equipment. Stereoscopic vision was easily obtained. The exoscope was perceived as providing higher quality magnification. We report our first clinical experience of exoscopic CC. The exoscope appears useful in the field of epilepsy surgery.

"General Principles When to Treat Seizures, W. Allen Hauser Pharmacologic Principles, Henn Kutt Fundamentals of Drug Therapy, Roger J. Porter Antiepileptic Drugs in Children, W. Edwin Dodson and James D. Reggin Antiepileptic Drugs in the Elderly, Fletcher H. McDowell Treatment Overview Neonatal Seizures, Cesare T. Lombroso Infantile Spasms, O. Carter Snead III Febrile Seizures, N. Paul Rosman Generalized Epilepsies, Dieter Janz and Walter Christe Partial Seizures, Noel Callaghan Treatment of Nonepileptic Events Presenting as Seizures Psychogenic Nonepileptic Events, John R. Gates Syncope, Douglas L. Wood and Bernard J. Gersh Parasomnias, Neil B. Kavey and Jamie Whyte Paroxysmal Dyskinesias, David A. Bennett When to Consider a Surgical Evaluation Indications for Epilepsy Surgery Evaluation, Prakash Kotagal and Hans Luders Corpus Callosotomy, Alexander G. Reeves Hemispherectomy, Jean-Guy Villemure Cerebral Angiomas Presenting with Seizures, Michael J. Aminoff Antiepileptic Drugs Ethosuximide, Allan L. Sherwin Valproate, J. Christine Dean and J. Kiffin Penry Phenytoin, Ilo E. Leppik Carbamazepine, D. Schmidt and E. Rohrer Oxcarbazepine, Lennart Gram and Peder Klosterskov-Jensen Vigabatrin, Paul J. Schechter Clobazam, Michael R. Trimble Clonazepam and Nitrazepam, Albert L. Larbrisseau Clorazepate Dipotassium, Alan Joseph Wilensky Diazepam, Henn Kutt Intermittent Home Treatment of Epileptic Relapses with Diazepam, Cesare T. Lombroso Lorazepam, Henn Kutt and Stanley R. Resor, Jr. Phenobarbital, Brian B. Gallagher Mephobarbital, W. D. Hooper and M. J. Eadie Primidone, Blaise F. D. Bourgeois Methsuximide, Basim M. Uthman and B. J. Wilder Phensuximide, Michael E. Newmark Phenacemide, Steven B. Coker Progabide, Pierre Loiseau and Bernard Duche Mephenytoin, Allan S. Troupin Ethotoin, Frank J. Ritter Acetazolamide, Stanley R. Resor, Jr. and Louise D. Resor Sulthiame, Wolfgang K. Baier and Herman Doose Other Treatments ACTH and Prednisone: Use in Seizure Disorders Other Than Infantile Spasms, O. Carter Snead III Ketogenic Diets, Douglas R. Nordli, Jr., Dorcas Koenigsberger, Joanne Schroeder, and Darryl C. De Vivo Drugs for Myoclonus L-5-Hydroxytryptophan, Melvin H. van Woert and Eunyong Chung Piracetam, Stephen Q. Shafer Special Problems Brand-Name Antiepileptic Drugs Versus Generics, Hart de Coudres Peterson Drugs That Can Precipitate Seizures, Brian K. Alldredge and Roger P. Simon Psychological Testing, Gregory P. Lee and David W. Loring Genetic Influences on Susceptibility to Seizures, Ruth Ottman Investigational Treatments Felbamate, Ilo E. Leppik and Harvey J. Kupferberg Electrical Stimulation of the Vagus Nerve, J. Kiffin Penry and J. Christine Dean Electrical Stimulation of the Thalamus, Francisco Velasco, Marcos Velasco, and Hilda Alcala Intravenous Immunoglobulins, K. van Rijckevorsel-Harmant and M. Delire Legal and Regulatory Issues"

Introduction Corpus callosotomy (CC) is an established surgical option for palliative treatment of medically intractable epilepsy, especially for seizures with drop attacks. We postulated that specific risk factors for post-CC transient disturbance of consciousness (pCTDC) are associated with CC. The purpose of this study was to review patients with intractable epilepsy who underwent CC and to statistically analyze risk factors for pCTDC. Methods Inclusion criteria for patients who underwent CC between January 2009 and November 2019 were: (1) ≥2 years old and (2) followed up for more than 8 months. The state of consciousness before and after CC was evaluated with the Glasgow coma scale. We statistically assessed predictors for pCTDC as the primary outcome. Results Fifty-six patients (19 females, 37 males) were enrolled, and the age range was 2–57 years old. Thirty-seven (66.1%) patients developed pCTDC. The mean period from the beginning of the state of pCTDC to recovery to their baseline conscious level was 4.9 days (range: 2–25 days). All three (100%) normal intelligence level patients, 13 (81%) of 16 patients with a moderately impaired level of intelligence, and 21 (57%) of 37 patients with a severely impaired level of intelligence exhibited pCTDC. Univariate (p = 0.044) and multivariate (p = 0.006) logistic regression analyses for predictors of pCTDC showed that intellectual function was statistically significant. Conclusion Two-thirds of patients developed pCTDC. One risk factor for pCTDC may be higher intellectual function.

OBJECTIVE The authors present a new “bloodless” technique for minimally invasive robotic thermocoagulative hemispherotomy (ROTCH). Such a method is being described in the literature for the first time. METHODS A robotic system was used to plan five sets of different trajectories: anterior disconnection, middle disconnection, posterior disconnection, corpus callosotomy, and temporal stem and amygdalar disconnection. A special technique, called the “X” technique, allowed planar disconnection. Registration was performed with surface landmarks (n = 5) and bone fiducials (n = 1). Coregistration with O-arm images was performed one or two times to confirm the trajectories (once for middle disconnection, and once for disconnection of the temporal stem and amygdala or body of the corpus callosum). Impedance measured before ablation allowed for minor adjustments. Radiofrequency ablation was performed at 75°C–80°C for 60 seconds. Surgical procedures were performed with multiple twist drills. After removal of the electrode, glue was used to prevent CSF leak, and a single stitch was applied. Follow-up CT and MRI were immediately performed. RESULTS The pathologies included Rasmussen's encephalitis (n = 2), hemispheric cortical dysplasia (n = 2), posttraumatic encephalomalacia (n = 1), and perinatal insult (n = 1). The mean ± SD (range) age was 6.7 ± 3.6 years (5 months to 10.2 years), and the right side was affected in 4 patients. The mean ± SD seizure frequency was 7.4 ± 5.6 seizures per day (1 patient had epilepsia partialis continua). The mean ± SD number of trajectories was 15.3 ± 2.5, and the mean ± SD number of lesions was 108 ± 25.8. The mean ± SD maximum numbers of trajectories and lesions required for middle disconnection were 7.1 ± 1.7 and 57.5 ± 18.4, respectively. All but 1 patient had class 1 outcomes according to the International League Against Epilepsy Outcome Scale at a mean ± SD (range) follow-up of 13.5 ± 1.6 (12–16) months; the remaining patient had a class 2 outcome. The estimated blood loss was < 5 ml for all patients. Complications included repeat surgery (after 2 weeks) for a “skip” area (n = 1) and a small temporal hematoma (n = 1), which resolved. CONCLUSIONS ROTCH seems to be a safe, feasible, and bloodless procedure, with a very low morbidity rate and promising outcomes.

Corpus callosotomy, first used in the management of epilepsy by William P. van Wagenen in 1940, was for years a contentious procedure. Two decades later, Nobel Laureate Roger W. Sperry's split-brain studies inspired surgeons to reexamine the role of corpus callosotomy in the control of epileptic seizures. In 1962, Joseph Bogen and Philip Vogel performed complete corpus callosotomies in patients with a history of generalized seizures. The identification of a set of postsurgical disconnection symptoms and other neurologic deficits begged the improvement of the surgical technique. Modifications to the operation, including anterior callosotomy, posterior callosotomy, partial callosotomy, staged callosotomy, microsurgical techniques, and radiosurgical techniques, continue to refine the procedure.

OBJECTIVE Epileptic spasms (ESs) are classified as focal, generalized, or unknown onset ESs. The classification of ESs and surgery in patients without lesions apparent on MRI is challenging. Total corpus callosotomy (TCC) is a surgical option for diagnosis of the lateralization and possible treatment for ESs. This study investigated phase-amplitude coupling (PAC) of fast activity modulated by slow waves on scalp electroencephalography (EEG) to evaluate the strength of the modulation index (MI) before and after disconnection surgery in children with intractable nonlesional ESs. The authors hypothesize that a decreased MI due to surgery correlates with good seizure outcomes. METHODS The authors studied 10 children with ESs without lesions on MRI who underwent disconnection surgeries. Scalp EEG was obtained before and after surgery. The authors collected 20 epochs of 3 minutes each during non–rapid eye movement sleep. The MI of the gamma (30–70 Hz) amplitude and delta (0.5–4 Hz) phase was obtained in each electrode. MIs for each electrode were averaged in 4 brain areas (left/right, anterior/posterior quadrants) and evaluated to determine the correlation with seizure outcomes. RESULTS The median age at first surgery was 2.3 years (range 10 months–9.1 years). Two patients with focal onset ESs underwent anterior quadrant disconnection (AQD). TCC alone was performed in 5 patients with generalized or unknown onset ESs. Two patients achieved seizure freedom. Three patients had residual generalized onset ESs. Disconnection surgeries in addition to TCC consisted of TCC + posterior quadrant disconnection (PQD) (1 patient); TCC + AQD + PQD (1 patient); and TCC + AQD + hemispherotomy (1 patient). Seven patients became seizure free with a mean follow-up period of 28 months (range 5–54 months). After TCC, MIs in 4 quadrants were significantly lower in the 2 seizure-free patients than in the 6 patients with residual ESs (p < 0.001). After all 15 disconnection surgeries in 10 patients, MIs in the 13 target quadrants for each disconnection surgery that resulted in freedom from seizures were significantly lower than in the 26 target quadrants in patients with residual ESs (p < 0.001). CONCLUSIONS In children with nonlesional ESs, PAC for scalp EEG before and after disconnection surgery may be a surrogate marker for control of ESs. The MI may indicate epileptogenic neuronal modulation of the interhemispheric corpus callosum and intrahemispheric subcortical network for ESs. TCC may be a therapeutic option to disconnect the interhemispheric modulation of epileptic networks.

Background Aicardi syndrome is a severe neurodevelopmental disorder that occurs primarily in females and is characterized by seizures, agenesis of the corpus callosum, and chorioretinal lacunae, which occur together in the majority of affected individuals. Seizures begin in infancy and tend to progress in intensity and are often refractory to standard multimodal medication treatments. Case Description We present here a unique case of a 12-year-old girl with partial agenesis of the corpus callosum who underwent a corpus callosotomy for treatment of medically refractory epilepsy. In so doing, we also review the literature with regard to the neurosurgical management of these unique patients. Conclusions For the subset of children who present with partial, rather than complete, agenesis of the corpus callosum, corpus callosotomy should be considered as a treatment option to reduce seizure burden.

Introduction Corpus callosotomy (CCT) is a palliative procedure to treat injurious drop attacks or multifocal/generalized seizures in which resection of the epileptogenic focus is not feasible. We are presenting our experience in treating intractable epilepsy patients by CCT procedures. Methods We observed 16 patients who underwent callosotomy (male to female ratio 7:9; adult to pediatric ratio 3:13). Initial seizure frequency was reported ranged from 1 to 2 attacks daily to very often (more than 20 episodes daily). Results Our observation showed that among patients with drop attacks, complete and >90% seizure freedom was reported by 4 and 6 of 13 patients, respectively (76.9% combined). Conclusion Our observation showed that corpus callosotomy yielded good outcome in patients with intractable epilepsy in Indonesia. Our observation showed total callosotomy achieved complete seizure freedom better compared to partial callosotomy patients.

Non-resective surgical strategies provide an alternative for drug-resistant patients not amenable to resective surgery due to poorly localized seizure foci, multiple foci, or epileptogenic zones co-localizing with eloquent areas carrying high risks for a resective procedure. They will not replace resective surgery, but rather complement the spectrum of surgical options. Palliative approaches comprising disconnective procedures (corpus callosotomy, CC; multiple subpial transections, MST) and neurostimulation (vagal nerve stimulation, VNS; deep brain stimulation, DBS; responsive neurostimulation, RNS) aim at reducing frequency and severity of most disabling seizures. The goal of curative non-resective surgery including ablative procedures (radiofrequency thermocoagulation, RFTC; laser-induced thermotherapy, LITT) and stereotactic radiosurgery (SRS) is to achieve complete seizure freedom as with resection. CC has been shown to reduce or abolish severe tonic or atonic drop attacks in around 90% of patients. As a stand-alone therapy, results of MST are modest with responder rates (defined as ≥50% decrease in seizure frequency) between 40% and 50%, and seizure-free outcome in 10–15% of patients. More favorable results with seizure control between 40% and 60% and responder rates between 80% and 90% can be achieved when MST are combined with resection. Neurostimulation procedures provide responder rates between 50% and 70%. Long-term assessment demonstrates continuously improving efficacy over many years suggesting a disease-modifying neuromodulation effect. With curative procedures, seizure-free outcome is achieved in 30–60% of patients. Curative stereotactic approaches can be expected to become first-line treatment options for selected patients with circumscribed lesions such as hypothalamic hamartomas, periventricular nodular heterotopias, and deep-seated focal cortical dysplasias. In addition, LITT may be considered as a minimally invasive alternative to resective surgery for mesiotemporal lobe epilepsies.

Magnetic resonance-guided laser interstitial thermal therapy (MRg-LITT) is becoming an increasingly used and more thoroughly understood method for real-time monitored thermal lesioning of tissue. It has found a particular niche in the treatment of medically refractory focal epilepsy for which it provides a less invasive alternative to craniotomy and resection for multiple pathologies such as mesial temporal lobe sclerosis, focal cortical dysplasia, cavernous malformations, hypothalamic hamartoma, and epileptogenic tumors. Stereotactic laser brain ablation is also an alternative to craniotomy for cortical resections in non-lesional epilepsy as well as to disconnection surgery as in corpus callosotomy. Clinical investigations have focused on understanding the advantages as well as limitations of using MRg-LITT in epilepsy surgery, especially for mesial temporal sclerosis (MTS), which has been the most studied etiology. Though laser ablation for MTS shows a good safety and efficacy profile compared to open surgery, the minimally invasive nature of this technique is also an attractive and promising method both for practitioners and patients for surgical treatment of multiple etiologies of focal epilepsy.

MRgLITT was first used for treatment of epilepsy in a child in 2010. Since that initial case, the technique has been applied to many pediatric epileptogenic targets such as tuberous sclerosis, mesial temporal lobe epilepsy, focal cortical dysplasia, periventricular nodular heterotopia, insular epilepsy, cavernous malformation, and, most efficiently, hypothalamic hamartoma. The combination of instant thermal ablation and peri-operative steroids to combat edema has resulted in an 83% 1-year seizure freedom rate with 1.5% rate of memory impairment, making it a profound improvement on open surgery. The technique has also been applied in disconnection, such as in corpus callosotomy, both in de novo and in salvage cases. In the treatment of drop attacks, three to four lasers can be employed to achieve the disconnection minimally invasively, obviating the need for a craniotomy. Outside of hypothalamic hamartoma, there have been few large pathology-based series, and long-term cognitive data is not available. MRgLITT in pediatric epilepsy holds the promise of less morbidity and shorter hospital stays, steps that may narrow the treatment gap in pediatric epilepsy surgery from anxiety and morbidity avoidance.