Corpus callosotomy outcomes in paediatric patients

Abstract

Corpus callosotomy is a palliative disconnective neurosurgical treatment that is typically employed for patients with medically refractory epilepsy characterised by injurious drop attacks. This thesis describes the 20 year experience with corpus callosotomy at Great Ormond Street Hospital for Children (GOSH) in London and the Children’s Hospital at Westmead (CHW) in Sydney. Between January 1995 and December 2015, 76 patients underwent corpus callosotomy at GOSH (n=47) and CHW (n=29); 55 patients met inclusion criteria. Patient records were analysed for changes in seizure type and frequency, changes in injuries, changes in use of antiepileptic drugs, and neurological and surgical complications. Rare or no drop attacks was analysed using Kaplan–Meier event-free survival curves using right-censoring of data. Multivariable regression analysis was used to assess the effect of clinical characteristics on outcome at last follow up. Median follow up was 36 months (interquartile range 34 months). Overall 26/55 patients (47.3%) had rare or no drop attacks at last follow up. Of the children who had drop attacks at last follow up, 26/29 of these patients (89.7%) had a return of drop attacks within 12 months of surgery. There were no significant predictors of developing drop attacks post-surgery. Neurological complications occurred in 11/55 operations (20.0%) and resolved within 6 weeks in all patients. Surgical complications occurred in 6/55 operations (10.9%), with only one major complication (hydrocephalus) and no deaths. Corpus callosotomy was a well-tolerated palliative procedure that was effective at reducing the severity of drop attacks in this case series. In patients for whom drop attacks return, they are likely to do so within 12 months of surgery. Several other case series and systematic reviews provide evidence to support the hypothesis that corpus callosotomy is a safe and effective palliative treatment for patients with medically refractory generalised seizures that is typically characterised by injurious drop attacks. But there is no strong evidence to demonstrate the validity of that hypothesis. A case study is presented to highlight some of the bioethical issues of corpus callosotomy in children. Parental resistance to epilepsy surgery is a well-known barrier to access for all epilepsy surgery. While earlier intervention has demonstrable benefits on quality of life, some parents find the prospect of disconnection syndrome challenging and resist corpus callosotomy. The case study is then used to frame issues relating to consent and the best interests of children undergoing corpus callosotomy, highlighting the shortcomings of the concept of autonomy.