title: Analysis of reoperation in mesial temporal lobe epilepsy with hippocampal sclerosis.
abstract: BACKGROUND
  Most patients do well after epilepsy surgery for mesial temporal lobe sclerosis, and in only 8 to 12% of all operations, the outcome is classified as not improved.
  
  
  OBJECTIVE
  To analyze the outcome of reoperation in cases of incomplete resection of mesial temporal lobe structures in patients with mesial temporal lobe sclerosis in temporal lobe epilepsy.
  
  
  METHODS
  We analyzed 22 consecutive patients who underwent reoperation for mesial temporal lobe sclerosis (follow-up, 23-112 months; mean, 43.18 months) by evaluating noninvasive electroencephalographic/video monitoring before the first and second surgeries (semiology, interictal epileptiform discharges, ictal electroencephalography with special attention to the secondary contralateral evolution of the electroencephalographic seizure pattern after the initial regionalization), and magnetic resonance imaging (resection indices after the first and second surgeries on the amygdala, hippocampus, lateral temporal lobe). In 18 of 22 patients T2 relaxometry of the contralateral hippocampus was performed.
  
  
  RESULTS
  Nine of 22 patients became seizure free; another 4 patients had a decrease in seizures and eventually became seizure free (range, 16-51 months; mean, 30.3). Recurrence of seizures is associated with (1) ictal electroencephalography with later evolution of an independent pattern over the contralateral temporal lobe (0 of 5 patients seizure free vs 5 of 7 patients non-seizure free; P = .046) and (2) a smaller amount of lateral temporal lobe resection in the second surgery (1.06 ± 0.59 cm vs 2.18 ± 1.37 cm; P = .019). No significant correlation with outcome was found for lateralization of interictal epileptiform discharges, change in semiology, other resection indices, T2 relaxometry, onset and duration of epilepsy, duration of follow-up, and side of surgery.
  
  
  CONCLUSIONS
  Patients have a less favorable outcome with a reoperation if they show ictal scalp electroencephalography with secondary contralateral propagation and if only a small second resection of the lateral temporal lobe is performed.
authors.affiliation: Bethel Epilepsy Center, Mara, Bielefeld, Germany. Reinhard.Schulz@mara.de
authors.forename: Reinhard
authors.initials: R
authors.lastname: Schulz
authors.forename: Matthias
authors.initials: M
authors.lastname: Hoppe
authors.forename: Frank
authors.initials: F
authors.lastname: Boesebeck
authors.forename: Csilla
authors.initials: C
authors.lastname: Gyimesi
authors.forename: Heinz W
authors.initials: HW
authors.lastname: Pannek
authors.forename: Friedrich G
authors.initials: FG
authors.lastname: Woermann
authors.forename: Theodor
authors.initials: T
authors.lastname: May
authors.forename: Alois
authors.initials: A
authors.lastname: Ebner
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D012086:Reoperation; D012598:Sclerosis / Q000150:complications / Q000473:pathology; D055815:Young Adult