Discontinuation of Anticonvulsant Medication after Epilepsy Surgery in Children

Abstract

Summary:Purpose: To evaluate the long-term outcome of medication-reduction/discontinuation trials after epilepsy surgery in pediatric patients.Methods: Of the total Bonn pediatric surgical sample (1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001); n = 251), we were able to obtain postsurgical follow-up data for 232 patients. We surveyed 140 of these patients by using a standardized telephone interview that addressed medicationreduction/discontinuation trials.Results: Of the 140 surveyed patients, 102 completely discontinued medication. Seven of these patients had recurring seizures that were controlled again after restarting the medication. Of 102 patients, 101 were completely seizure free during the 3 months before the survey. Postsurgical epileptic events before the trial significantly increased the risk for recurring epileptic events after the trial. Two surveyed patients lost postsurgical seizure freedom after medication reduction. We were also able to identify from the records another nine patients with complete medication discontinuation and seven patients with medication reduction. Two of these latter patients lost postsurgical seizure freedom despite restarting their medication. The total rate of patients with medication-reduction/discontinuation trials was 55%. The seizure recurrence rate in these patients was 10%. Recurring seizures could not be controlled by restarted medication in 3% of the trials. Currently, 90% of patients with discontinuation trials were seizure free without medication.Conclusions: The reduction/withdrawal of anticonvulsant medication after successful epilepsy surgery has a low risk of seizure recurrence for pediatric patients in long-term follow-up, particularly in cases of complete postsurgical seizure freedom before the trial. Key Words: Epilepsy surgery in childrenMedication withdrawal-Anticonvulsants.Epilepsy surgery is acknowledged as a highly effective therapeutic intervention for children and adults with pharmacoresistant focal seizures. Earlier studies with relatively short outcome periods are now being compared with long-term outcome (≥5 years seizure free) (1). The postoperative long-term outcome in pediatric and adult samples is similar, with 60-70% (2-6) of patients experiencing a complete relief from seizures. A recent review (7) raised the issue as to whether successful epilepsy surgery may be regarded as "curative" (i.e., sustained seizure freedom without medication). According to Schmidt et al. (7), only 40-60% of the seizure-free adult patients risk a medication-discontinuation trial. About one third of these patients experience a recurrence of epileptic events after the withdrawal trial as compared with 7-17% of postsurgical patients under continued medication. those patients who experience seizure recurrence does not guarantee complete seizure relief. The authors hypothesize as to whether the outcome of the discontinuation trials might be advantageous in pediatric samples. They refer to a preliminary poster abstract (8) [higher...

Long-term outcome of hemispheric surgery at different ages in 61 epilepsy patients

“…Therefore, the advantageous seizure outcome in younger patients provides indirect evidence for the concept of epileptogenic network formation in previously non-epileptogenic tissue during the course of uncontrolled epilepsy 27. Studies on AED withdrawal after successful focal epilepsy surgery similarly suggest a higher rate of seizure freedom with no further need for AEDs in younger patients with shorter epilepsy duration as compared with adult patients 28. Evidently, the obtained age-at-surgery effect on seizures requires confirmation from other groups.…”

How safe is it to withdraw antiepileptic drugs following successful surgery for mesial temporal lobe epilepsy?

“…(2004), we could gather seven studies that primarily addressed AED withdrawal after epilepsy surgery. Three of them addressed epilepsy surgery outcome in the pediatric age group (Hoppe et al., 2006; Sinclair et al., 2007; Lachhwani et al., 2008), and one study comprised patients who underwent temporal and extratemporal resections (Park et al., 2010). The remaining three studies investigated the seizure outcome and the factors that influenced the outcome of patients with temporal lobe epilepsy (Kim et al., 2005; Al‐Kaylani et al., 2007; Lee et al., 2008).…”

Improved outcomes in pediatric epilepsy surgery

“…17,26 The number of reoperations, and eventual seizure-free patients off medications with longer follow-up durations, are similar between our series and the literature. 10,[27][28][29][30] Phase II intracranial EEG studies were used at a lower rate than usually reported. The ILAE survey of 20 pediatric epilepsy surgery centers involving 543 children found that intracranial electrodes were used in 27% of patients.…”