Clinical profiles for seizure remission and developmental gains after total corpus callosotomy

Applications of magnetic resonance-guided laser interstitial thermal therapy in disconnective epilepsy surgery

Minimally invasive surgical techniques, such as MR-guided laser interstitial thermal therapy (LITT), have emerged as promising alternatives to open disconnective surgeries in drug-resistant epilepsy (DRE). This review synthesizes current literature on the application of LITT for corpus callosal disconnection and functional hemispheric disconnection. Studies highlight LITT's effectiveness for achieving seizure control and functional outcomes, often with reduced complications compared to traditional open procedures. Challenges include technical limitations to achieving total disconnection and adequate assessment of disconnection postoperatively. The literature is largely composed of observational studies and there is a need for rigorous, multi-center trials to establish robust guidelines and improve generalizability in clinical practice. There is also a need for a more robust exploration of how patient-specific factors contribute to response or nonresponse to intervention.

Corpus callosotomy for refractory epileptic spasms: Systematic review and meta-analysis

OBJECTIVE

We systematically reviewed the existing literature on the efficacy of corpus callosotomy (CC) in children and adults with refractory epileptic spasms (ES) and analyzed clinical determinants of seizure outcomes.

METHODS

The Preferred Report Items for Systematic Reviews and Meta-Analysis Guidelines (PRISMA) were followed. We systematically searched MEDLINE, EMBASE and Cochrane databases up to December 2023 for original research articles on using CC to treat refractory ES. The primary outcome measure was the proportion of study participants who achieved seizure freedom following initial CC at the last follow-up. Meta-regression using mixed-effects models was performed to obtain clinical determinants of seizure outcomes.

RESULTS

A total of 12 studies were included (253 individuals). Initial complete total CC was most common (n = 218/253, 86%), followed by anterior CC (n = 29/253, 12%) and other forms of CC (i.e., anterior to posterior, posterior, staged total) (n = 6/253, 2%). The pooled proportion of patients achieving spasm freedom following CC was 0.31 (95% CI: 0.22, 0.42) (mean follow-up 47 months). Meta-regression showed that structural etiology and mean age at the time of CC were significant moderators of the pooled effect. For every 1% increase in the proportion of structural etiology, the proportion of spasm-free outcome was found to reduce by 0.45 (95% CI: -0.86, -0.03, p < 0.0001). In addition, increasing the mean age by 1 month led to a reduction in the proportion of spasms-free patients by 0.003 (95% CI: -0.005, -0.0006, p = 0.01). Sixty-two individuals (24%) from seven studies underwent further surgery for residual ES; 34 became spasm free (55%).

CONCLUSIONS

Corpus callosotomy may be an effective treatment option in selected individuals with refractory epileptic spasms. Structural aetiologies and increased age at the time of corpus callosotomy are important clinical determinants. In some cases, CC may lead to further epilepsy surgery.

The clinical features of patients with seizure freedom and failure after total corpus callosotomy for childhood-onset refractory epilepsy

BACKGROUND

Corpus callosotomy is a palliative surgery for medically refractory epilepsy. We aim to analyze the clinical features of patients with seizure freedom and failure after total corpus callosotomy for childhood-onset refractory epilepsy.

METHODS

We retrospectively reviewed the clinical courses of patients with childhood-onset refractory epilepsy undergoing total corpus callosotomy between May 2009 and March 2019. Seizure outcome at the last follow-up was the primary outcome. The clinical features of patients with seizure freedom and failure after callosotomy were compared.

RESULTS

Eighty patients with childhood-onset refractory epilepsy underwent total corpus callosotomy; 15 (18.8%) obtained freedom from all seizures and 19 (23.8%) had unworthwhile improvement and failure. The mean ages at seizure onset in patients with seizure freedom and failure after callosotomy were 5.7 and 5.9 years; and mean seizure durations were 9.4 and 11.5 years, respectively. Univariate analysis found epilepsy syndrome (p = 0.047), mental retardation (p = 0.007), previous medical history (p = 0.004), ≥10 seizures per day (p = 0.024), theta waves in the background electroencephalogram (p = 0.024), and acute postoperative seizure (p = 0.000) were associated with failure after callosotomy. Seizure freedom after callosotomy was more common among patients with less than 10 seizures per day.

CONCLUSIONS

Total corpus callosotomy is an effective palliative procedure for childhood-onset refractory epilepsy, particularly for patients with specific clinical characteristics. Callosotomy has a high seizure-free rate in well-selected patients.

Long-term follow-up seizure outcomes after corpus callosotomy: A systematic review with meta-analysis

BACKGROUND

Corpus callosotomy (CC) is appropriate for patients with seizures of a bilateral or diffuse origin, or those with seizures of a unilateral origin with rapid spread to the contralateral cerebral hemisphere. The efficiency of CC in patients with drug-resistant epilepsy is a long-term concern because most articles reporting the surgical results of CC arise from small case series, and the durations of follow-up vary.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were searched to identify papers published before November 8, 2021. The systematic review was completed following PRISMA guidelines. Outcomes were analyzed by meta-analysis of the proportions.

RESULTS

A total of 1644 patients with drug-resistant epilepsy (49 retrospective or prospective case series studies) underwent CC, and the follow-up time of all patients was at least 1 year. The rate of complete seizure freedom (SF) was 12.38% (95% confidence interval [CI], 8.17%-17.21%). Meanwhile, the rate of complete SF from drop attacks was 61.86% (95% CI, 51.87%-71.41%). The rates of complete SF after total corpus callosotomy (TCC) and anterior corpus callosotomy (ACC) were 11.41% (95% CI, 5.33%-18.91%) and 6.75% (95% CI, 2.76%-11.85%), respectively. Additionally, the rate of complete SF from drop attacks after TCC was significantly higher than that after ACC (71.52%, 95% CI, 54.22%-86.35% vs. 57.11%, 95% CI, 42.17%-71.49%). The quality of evidence for the three outcomes by GRADE assessment was low to moderate.

CONCLUSION

There was no significant difference in the rate of complete SF between TCC and ACC. TCC had a significantly higher rate of complete SF from drop attacks than did ACC. Furthermore, CC for the treatment of drug-resistant epilepsy remains an important problem for further investigation because there are no universally accepted standardized guidelines for the extent of CC and its benefit to patients. In future research, we will focus on this issue.

Re-appraisal of callosotomy: rates and predictors of short-term seizure outcome in pediatric epileptic encephalopathy

Background

Epilepsy is a chronic debilitating disease especially in pediatric population. Most of reported studies for corpus callosotomy as a palliative surgery in drug-resistant cases are on limited number of cases and there is scarcity in literature for outcomes reported from developing countries. Here, we present our study on a large series of cases with analysis of potential predicators outcomes in the era of more expensive devices like vagal nerve stimulation to give a litany on a universal epilepsy surgery procedure which had been missed in the literature through the last decade.

Results

An observational retrospective study was done reviewing 129 patients with PEE underwent open microscopic corpus callosotomy. Total and drop attack seizure outcomes were studied after surgery. Potential outcomes predictors studied are: preoperative EEG and MRI. Preoperative IQ impairment epilepsy duration, age at diagnosis, MRI finding, IQ score, EEG findings, history of infantile spasm and extent of callosotomy done. All the recorded outcomes were substantially improved after callosotomy in our study population of 129 pediatric patients. The median (IQR) preoperative drop attack frequency was 70 (21–140) which decreased to 3 (0–14) postoperatively. Similarly, the number of anti-epileptics used by patients had a median of 3 (2–4) which decreased to 2 (2–3) after the surgery. All patients were experiencing status epilepticus which disappeared in 72% of the patients after callosotomy. Preoperative normal MRI was a predictor for drop attack favorable outcome and mild preoperative impairment of IQ was a predictor of favorable total seizure and drop attack outcome.

Conclusions

Corpus callosotomy is a well-tolerated palliative procedure for drug-resistant generalized epilepsy notably, drop attacks which had its notorious effect on quality of life of pediatric patients and their families, no appreciable prognostic factors for favorable outcome were clearly observed except for normal preoperative MRI, mild preoperative IQ affection, and complete callosotomy.

Callosotomy vs Vagus Nerve Stimulation in the Treatment of Lennox-Gastaut Syndrome: A Systematic Review With Meta-Analysis

BACKGROUND

Lennox-Gastaut syndrome (LGS) is a severe drug-resistant epileptic syndrome. Palliative treatments such as corpus callosotomy (CC) and vagus nerve stimulation (VNS) have emerged as treatments to reduce the number of seizures in patients. The aim of this study is to compare the effectiveness of CC and VNS in patients with LGS studied in the last 30 years.

MATERIALS AND METHODS

We conducted a systematic review with meta-analysis and collected papers from PubMed (MEDLINE), Ovidsp, Web of Science, and Cochrane Library data bases. The articles analyzed were published between January 1990 and December 2020. Keywords were chosen based on internal and external validation in the PubMed data base (the analysis is available in the Supplementary Data Supplementary Appendix). Prospective or retrospective case reports (n ≥ 2), case series, cohort studies, or case-control studies involving patients with LGS were included in the analysis. We selected studies that had no age or sex restriction and that provided data on seizures before and after treatments. Studies not written in English, published without peer review, or not indexed in the data bases were excluded. Other exclusion criteria were the absence of seizure data and the impossibility of extracting this information from the studies. To analyze the results, we used the random-effects model based on the assessment of heterogeneity (I² statistics) in two scenarios. In scenario 1, we assessed the incidence of patients with a seizure reduction ≥ 50%; in scenario 2, we assessed the incidence of patients with a seizure reduction > 0%.

RESULTS

Of the 7418 articles found using the keywords, 32 were considered eligible. Of these, 18 articles were on VNS (175 patients) and 14 on CC (107 patients). For scenario 1 (seizure reduction ≥ 50%), CC had an incidence of 65% (95% CI, 37%-94%), with an I² value of 82.7%; VNS had an incidence of 34% (95% CI, 11%-57%), with an I² value of 80.7%. For scenario 2 (seizure reduction > 0%), CC had an incidence of 80% (95% CI, 58%-100%), with an I² value of 84.7%; VNS had an incidence of 64% (95% CI, 38%-89%), with an I² value of 90.8%. There was an overlap of confidence intervals, with no statistical difference between the treatments in both scenarios.

DISCUSSION

Our analysis of LGS showed that the CC and VNS treatments are significantly beneficial to reducing seizures, without superiority between them.

The role of neurosurgery in the management of tuberous sclerosis complex–associated epilepsy: a systematic review

OBJECTIVE

Tuberous sclerosis complex (TSC) is an autosomal dominant, multisystem neurocutaneous disorder associated with cortical tubers, brain lesions seen in nearly all patients with TSC, which are frequently epileptogenic. Seizures are often the earliest clinical manifestation of TSC, leading to epilepsy in over 70% of patients. Medical management with antiepileptic drugs constitutes early therapy, but over 50% develop medically refractory epilepsy, necessitating surgical evaluation and treatment. The objective of this study was to summarize the literature and report seizure outcomes following surgical treatment for TSC-associated epilepsy.

METHODS

A systematic literature review was performed in accordance with the PRISMA guidelines. The PubMed and Embase databases were searched for journal articles reporting seizure outcomes following epilepsy surgery in TSC patients. Included studies were placed into one of two groups based on the surgical technique used. Excellent and worthwhile seizure reductions were defined for each group as outcomes and extracted from each study.

RESULTS

A total of 46 studies were included. Forty of these studies reported seizure outcomes following any combination of resection, disconnection, and ablation on a collective 1157 patients. Excellent and worthwhile seizure reductions were achieved in 59% (683/1157) and 85% (450/528) of patients, respectively. Six of these studies reported seizure outcomes following treatment with neuromodulation. Excellent and worthwhile seizure reductions were achieved in 34% (24/70) and 76% (53/70) of patients, respectively.

CONCLUSIONS

Surgery effectively controls seizures in select patients with TSC-associated epilepsy, but outcomes vary. Further understanding of TSC-associated epilepsy, improving localization strategies, and emerging surgical techniques represent promising avenues for improving surgical outcomes.

Corpus Callosotomy in the Modern Era: Origins, Efficacy, Technical Variations, Complications, and Indications

Corpus callosotomy is among the oldest surgeries performed for drug-resistant epilepsy (DRE). First performed in 1940, various studies have since assessed its outcomes in various patient populations in addition to describing different extents of sectioning and emerging technologies (i.e. endoscopic, laser interstitial thermal therapy, and radiosurgery). In order to capture the current state and offer a reappraisal, we comprehensively review corpus callosotomy's origins, efficacy for various seizure types, technical variations, complications, and indications and compare the procedure to vagus nerve stimulation therapy which has similar indications. We consider corpus callosotomy to be a safe and efficacious procedure that should be considered by clinicians when appropriate. Furthermore, it can also play an important role in treating patients with DRE in low-to-middle-income countries where resources are limited.

Corpus Callosotomy for Controlling Epileptic Spasms: A Proposal for Surgical Selection

In 1940, van Wagenen and Herren first proposed the corpus callosotomy (CC) as a surgical procedure for epilepsy. CC has been mainly used to treat drop attacks, which are classified as generalized tonic or atonic seizures. Epileptic spasms (ESs) are a type of epileptic seizure characterized as brief muscle contractions with ictal polyphasic slow waves on an electroencephalogram and a main feature of West syndrome. Resection surgeries, including frontal/posterior disconnections and hemispherotomy, have been established for the treatment of medically intractable ES in patients with unilaterally localized epileptogenic regions. However, CC has also been adopted for ES treatment, with studies involving CC to treat ES having increased since 2010. In those studies, patients without lesions observed on magnetic resonance imaging or equally bilateral lesions predominated, in contrast to studies on resection surgeries. Here, we present a review of relevant literature concerning CC and relevant adaptations. We discuss history and adaptations of CC, and patient selection for epilepsy surgeries due to medically intractable ES, and compared resection surgeries with CC. We propose a surgical selection flow involving resection surgery or CC as first-line treatment for patients with ES who have been assessed as suitable candidates for surgery.

Developmental outcome after corpus callosotomy for infants and young children with drug-resistant epilepsy

AIM

To examine the developmental and seizure outcomes after corpus callosotomy (CC) in early childhood.

METHODS

We retrospectively identified 106 patients who underwent CC for drug-resistant epilepsy before the age of 6 years, at the Nagasaki Medical Center, between July 2002 and July 2016. Patients' developmental outcomes were evaluated one year after CC using the Kinder Infant Development Scale.

RESULTS

The mean preoperative developmental quotient (DQ) was 25.0 (standard deviation [SD], 20.8), and the mean difference between preoperative DQ and one-year postoperative DQ was -1.6 points (SD, 11.6). However, 42.5% of patients had a mean DQ increase of 6.5 points (SD, 6.4), one year after CC from that before surgery. Factors related to the improvement in postoperative DQ were 'low preoperative DQ', 'developmental gain 1 month postoperatively', and 'postoperative seizure-free state'. Approximately 21.7% of patients were seizure-free 1 year after CC.

INTERPRETATION

Performing CC, in infancy and early childhood for patients with drug-resistant epilepsy and severe developmental impairment, was associated with improved development in 42.5% of patients. Remission of seizures, even if only for a short period, contributed to developmental improvement. From a developmental perspective, CC for drug-resistant epilepsy in early childhood is an effective treatment.

Phase Lag Analyses on Ictal Scalp Electroencephalography May Predict Outcomes of Corpus Callosotomy for Epileptic Spasms

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.

Alteration of the anatomical covariance network after corpus callosotomy in pediatric intractable epilepsy

PURPOSE

This study aimed to use graph theoretical analysis of anatomical covariance derived from structural MRI to reveal how the gray matter connectivity pattern is altered after corpus callosotomy (CC).

MATERIALS AND METHODS

We recruited 21 patients with epilepsy who had undergone CC. Enrollment criteria were applied: (1) no lesion identified on brain MRI; (2) no history of other brain surgery; and (3) age not younger than 3 years and not older than 18 years at preoperative MRI evaluation. The most common epilepsy syndrome was Lennox-Gastaut syndrome (11 patients). For voxel-based morphometry, the normalized gray matter images of pre-CC and post-CC patients were analyzed with SPM12 (voxel-level threshold of p<0.05 [familywise error-corrected]). Secondly, the images of both groups were subjected to graph theoretical analysis using the Graph Analysis Toolbox with SPM8. Each group was also compared with 32 age- and sex-matched control patients without brain diseases.

RESULTS

Comparisons between the pre- and post-CC groups revealed a significant reduction in seizure frequency with no change in mean intelligence quotient/developmental quotient levels. There was no relationship among the three groups in global network metrics or in targeted attack. A regional comparison of betweenness centrality revealed decreased connectivity to and from the right middle cingulate gyri and medial side of the right superior frontal gyrus and a partial shift in the distribution of betweenness centrality hubs to the normal location. Significantly lower resilience to random failure was found after versus before CC and versus controls (p = 0.0450 and p = 0.0200, respectively).

CONCLUSION

Graph theoretical analysis of anatomical covariance derived from structural imaging revealed two neural network effects of resection associated with seizure reduction: the reappearance of a structural network comparable to that in healthy children and reduced connectivity along the median line, including the middle cingulate gyrus.

Analysis for the Association Between Corpus Callosum Thickness and Corpus Callosotomy Outcomes for Patients With Epileptic Spasms or Tonic Spasms

BACKGROUND

This retrospective study is designed to determine whether the thickness of the corpus callosum can predict corpus callosotomy outcome in pediatric patients with epileptic or tonic spasms.

METHODS

We retrospectively studied 25 patients (18 boys) with intractable childhood-onset epileptic or tonic spasms who underwent corpus callosotomy between March 2008 and January 2017. Seizure outcomes were classified as favorable (class I and II of Engel's outcome classification) or unfavorable (class III and IV of Engel's outcome classification) at 12 months postoperatively. We measured the corpus callosum area on the midline and maximum cerebral area on the para-midline in sagittal magnetic resonance images just before surgery. We statistically analyzed the associations between surgical outcomes and corpus callosum area, corpus callosum area/maximum cerebral area (corpus callosum/cerebrum ratio), or age at magnetic resonance imaging just before surgery, using univariate and multivariate logistic regression analyses.

RESULTS

Age at surgery ranged from six to 237 months (mean: 119). Main seizure types were epileptic spasms in 17 patients and tonic spasms in eight. Favorable outcomes occurred in 10 (40%) patients and unfavorable outcomes in 15 (60%). Both corpus callosum area and corpus callosum/cerebrum ratio did not show significant associations with the outcomes in the univariate and multivariate analyses. The 95% confidence intervals of corpus callosum/cerebrum ratio strongly overlapped between the favorable and unfavorable outcome groups.

CONCLUSIONS

Our data failed to support that corpus callosum thickness on the sagittal image is associated with corpus callosotomy outcomes in pediatric patients with epileptic spasms or tonic spasms.

Rates and predictors of seizure outcome after corpus callosotomy for drug-resistant epilepsy: a meta-analysis

OBJECTIVE

Corpus callosotomy is a palliative surgery for drug-resistant epilepsy that reduces the severity and frequency of generalized seizures by disconnecting the two cerebral hemispheres. Unlike with resection, seizure outcomes remain poorly understood. The authors systematically reviewed the literature and performed a meta-analysis to investigate rates and predictors of complete seizure freedom and freedom from drop attacks after corpus callosotomy.

METHODS

PubMed, Web of Science, and Scopus were queried for primary studies examining seizure outcomes after corpus callosotomy published over 30 years. Rates of complete seizure freedom or drop attack freedom were recorded. Variables showing a potential relationship to seizure outcome on preliminary analysis were subjected to formal meta-analysis.

RESULTS

The authors identified 1742 eligible patients from 58 included studies. Overall, the rates of complete seizure freedom and drop attack freedom after corpus callosotomy were 18.8% and 55.3%, respectively. Complete seizure freedom was significantly predicted by the presence of infantile spasms (OR 3.86, 95% CI 1.13-13.23), normal MRI findings (OR 4.63, 95% CI 1.75-12.25), and shorter epilepsy duration (OR 2.57, 95% CI 1.23-5.38). Freedom from drop attacks was predicted by complete over partial callosotomy (OR 2.90, 95% CI 1.07-7.83) and idiopathic over known epilepsy etiology (OR 2.84, 95% CI 1.35-5.99).

CONCLUSIONS

The authors report the first systematic review and meta-analysis of seizure outcomes in both adults and children after corpus callosotomy for epilepsy. Approximately one-half of patients become free from drop attacks, and one-fifth achieve complete seizure freedom after surgery. Some predictors of favorable outcome differ from those in resective epilepsy surgery.

Safety and effectiveness of surgery for epilepsy in children. Experience of a tertiary hospital in Ecuador

INTRODUCTION

There is sufficient evidence on the usefulness of surgery as a therapeutic alternative for patients with drug-resistant epilepsy; however this treatment is underutilized, especially in developing countries.

METHODS

We describe the outcomes of epilepsy surgery in 27 paediatric patients at Hospital Baca Ortiz in Quito, Ecuador. Our analysis considered the following variables: reduction in seizure frequency, surgery outcome according to the Engel classification, improvement in quality of life, and serious complications due to surgery.

RESULTS

21 corpus callosotomies and 6 resective surgeries were performed. The mean seizure frequency decreased from 465 per month before surgery to 37.2 per month thereafter (p<.001); quality of life scale scores increased from 12.6 to 37.2 (p<.001), and quality of life improved in 72.7% of patients. Regarding resective surgery, 2 patients with temporal lobe epilepsy and one with posterior quadrant epilepsy achieved Engel class IA, and one patient undergoing hemispherotomy due to Rasmussen encephalitis achieved Engel class IIA. Two patients underwent surgery for hypothalamic hamartoma: one achieved Engel III and the other, Engel IA; however, the latter patient died in the medium term due to a postoperative complication. The other major complication was a case of hydrocephalus, which led to the death of a patient with refractory infantile spasms who underwent corpus callosotomy.

CONCLUSIONS

Favourable outcomes were observed in 92.5% of patients.

Seizure outcome after corpus callosotomy in a large paediatric series

AIM

To describe 20 years of experience with corpus callosotomy at Great Ormond Street Hospital for Children, London and the Children's Hospital at Westmead, Sydney.

METHOD

Records of patients who underwent corpus callosotomy between January 1995 and December 2015 were reviewed. Complications of surgery and changes in seizure type and frequency, injuries, and use of antiepileptic drugs were recorded. Drop attacks were analysed using Kaplan-Meier event-free survival curves. Multivariable regression analysis was used to assess the effect of clinical characteristics on outcome at last follow-up.

RESULTS

Inclusion criteria were met for 55 patients younger than 18 years of age. Median follow-up length was 36 months. At the last follow-up, 26 out of 55 patients (47%) had rare or no drop attacks. In those without a good outcome at final follow-up, 26 out of 29 (90%) had drop attacks return within 12 months of surgery. There were no preoperative predictors of developing drop attacks postoperatively. The median number of antiepileptic drugs significantly reduced from three to two. Transient neurological complications were experienced by 11 out of 55 patients (20%) and 6 out of 55 patients had surgical complications (11%).

INTERPRETATION

Corpus callosotomy is a well-tolerated procedure that is effective at reducing the severity of drop attacks in paediatric patients. Drop attacks that do return are likely to do so within 12 months and the number of antiepileptic drugs can be significantly reduced.

WHAT THIS PAPER ADDS

Corpus callosotomy is an effective palliative treatment and well tolerated in children. Good outcomes for the first 12 months after surgery were likely to continue. The number of antiepileptic drugs can be significantly reduced after corpus callosotomy. Patients with fewer than three types of seizure had better outcomes. There were fewer injuries from drop attacks after surgery.