title: Discontinuation of antiepileptic drugs after successful epilepsy surgery.
abstract: OBJECTIVE
  To evaluate the frequency and risk factors for seizure recurrence subsequent to antiepileptic drug (AED) withdrawal in patients who underwent surgical treatment for intractable partial epilepsy and were rendered seizure-free.
  
  
  METHODS
  The outcome of discontinuation of AED medication was studied retrospectively in 210 consecutive patients who were rendered seizure-free after epilepsy surgery performed between 1989 and 1993.
  
  
  RESULTS
  Medical therapy was reduced in 96 patients and discontinued in 84 patients. The seizure recurrence rate after complete AED withdrawal was 14% and 36% at 2 and 5 years. In contrast, only 3% and 7% of the 30 patients who did not alter AED treatment after surgery had recurrent seizures in the same time intervals. After AED discontinuation, seizures tended to recur more often in patients with normal preoperative MRI studies compared with those with focal pathology. However, this difference did not reach significance. Intraoperative electrocorticography, extent of surgical resection, postoperative EEG, and seizure-free duration after surgery were not predictive of seizure outcome after AED withdrawal.
  
  
  CONCLUSIONS
  AED withdrawal was associated with seizure recurrence in a significant portion of patients rendered seizure-free by epilepsy surgery. Patients with a normal preoperative MRI study showed a tendency for higher seizure recurrence, whereas the duration of seizure-free postoperative AED treatment interval did not significantly influence the seizure recurrence rate. These results will prove useful in counseling patients about discontinuing AED treatment after successful epilepsy surgery.
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Schiller
authors.forename: G D
authors.initials: GD
authors.lastname: Cascino
authors.forename: E L
authors.initials: EL
authors.lastname: So
authors.forename: W R
authors.initials: WR
authors.lastname: Marsh
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000139:chemically induced / Q000188:drug therapy* / Q000601:surgery*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D018570:Risk Assessment; D012640:Seizures / Q000139:chemically induced / Q000188:drug therapy / Q000601:surgery; D013375:Substance Withdrawal Syndrome
chemical_list: D000927:Anticonvulsants