Awake Epilepsy Surgery in Patients with Focal Cortical Dysplasia

World Neurosurg. 2021 Jul:151:e257-e264. doi: 10.1016/j.wneu.2021.04.021. Epub 2021 Apr 16.

Abstract

Background: Awake craniotomy (AC) and direct electric stimulation emerged together with epilepsy surgery >80 years ago. The goal of our study was to evaluate the benefits of awake surgery in patients with drug-resistant epilepsy caused by focal cortical dysplasia (FCD) affecting eloquent areas.

Methods: Our material included 95 patients with drug-resistant epilepsy and FCD, who were operated on between January 2009 and December 2018. These 95 patients were assigned into 3 groups: AC; general anesthesia (GA) with intraoperative neuromonitoring; and GA without intraoperative neuromonitoring. We investigated the following variables: age at surgery, lesion side, eloquent cortex involvement, brain mapping success rate, epilepsy surgery success rate, intraoperative complications, postoperative complications, and intraoperative changes of the preoperative resection plan according to results of the brain mapping by direct electric stimulation.

Results: We found statistically significant differences between the AC and GA groups in the mean age at operation, lesion side, eloquent localization, and postoperative transient neurologic deficit. Seizure outcome in the AC was satisfactory (71% complete seizure control) and comparable to the seizure outcome in the GA groups. Our preoperative plan was changed because of functional constraints in 6 patients (43%) operated on during AC.

Conclusions: AC during epilepsy surgery for FCD in eloquent areas may change the preoperative plan. The good rate of postoperative seizure control and the absence of permanent postoperative neurologic deficit in our series is the main proof that AC is a useful tool in patients with FCD involving the eloquent cortex.

Keywords: Awake craniotomy; Brain mapping; Epilepsy surgery; Focal cortical dysplasia.

MeSH terms

  • Adolescent
  • Adult
  • Cerebral Cortex / physiopathology
  • Cerebral Cortex / surgery*
  • Epilepsy / complications
  • Epilepsy / etiology
  • Epilepsy / physiopathology
  • Epilepsy / surgery*
  • Female
  • Humans
  • Intraoperative Neurophysiological Monitoring / methods*
  • Male
  • Malformations of Cortical Development, Group I / complications
  • Malformations of Cortical Development, Group I / physiopathology
  • Malformations of Cortical Development, Group I / surgery*
  • Neurosurgical Procedures / methods*
  • Treatment Outcome
  • Young Adult

Supplementary concepts

  • Focal cortical dysplasia of Taylor