Seizure outcome after anterior temporal lobectomy and its predictors in patients with apparent temporal lobe epilepsy and normal MRI

Epilepsia. 2004 Jul;45(7):803-8. doi: 10.1111/j.0013-9580.2004.48503.x.


Purpose: Very little reliable information is available regarding the role of anterior temporal lobectomy (ATL), optimal presurgical evaluation strategy, post-ATL seizure outcome, and the factors that predict the outcome in patients with medically refractory temporal lobe epilepsy (TLE) and normal high-resolution magnetic resonance imaging (MRI). To be cost-effective, epilepsy surgery centers in developing countries will have to select candidates for epilepsy surgery by using the locally available technology and expertise.

Methods: We reviewed the electroclinical and pathological characteristics and seizure outcome of 17 patients who underwent ATL for medically refractory TLE after being selected for ATL based on a noninvasive selection protocol without the aid of positron emission tomography (PET) or single-photon emission computed tomography (SPECT), despite a normal preoperative high-resolution MRI.

Results: Seven (41%) patients achieved an excellent seizure outcome; five of them were totally seizure free. An additional five (29%) patients had >75% reduction in seizure frequency. The following pre-ATL factors predicted an excellent outcome: antecedent history of febrile seizures, strictly unilateral anterior temporal interictal epileptiform discharges (IEDs), and concordant type 1 ictal EEG pattern. All the five patients with pathologically verified hippocampal formation neuronal loss were seizure free. The presence of posterior temporal, bilateral temporal, and generalized IEDs portended unfavorable post-ATL seizure outcome.

Conclusions: A subgroup of patients destined to have an excellent post-ATL outcome can be selected from MRI-negative TLE patients by using history and scalp-recorded interictal and ictal EEG data. The attributes of these patients are antecedent history of febrile seizures, strictly unilateral anterior IEDs, and concordant type 1 ictal EEG pattern.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Anterior Temporal Lobectomy / methods*
  • Electroencephalography / statistics & numerical data
  • Epilepsy, Temporal Lobe / diagnosis
  • Epilepsy, Temporal Lobe / mortality
  • Epilepsy, Temporal Lobe / pathology
  • Epilepsy, Temporal Lobe / surgery*
  • Female
  • Follow-Up Studies
  • Hippocampus / pathology
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Prognosis
  • Temporal Lobe / pathology
  • Temporal Lobe / surgery*
  • Treatment Outcome