Incomplete resection of focal cortical dysplasia is the main predictor of poor postsurgical outcome
1Department of Pediatric Neurology, Charles University, Second Medical School, Motol University Hospital, V Uvalu 84, CZ 15006 Prague 5, Czech Republic. pavel.krsek@post.cz
Insights
Complete surgical resection of focal cortical dysplasia (FCD) is key for seizure control in children. Ensuring the entire abnormal area is removed significantly improves epilepsy surgery outcomes.
Area of Science:
- Pediatric Neurology
- Epilepsy Surgery
- Neurodevelopmental Disorders
Background:
- Focal cortical dysplasia (FCD) is a primary cause of intractable childhood epilepsy.
- Understanding factors influencing epilepsy surgery outcomes in pediatric FCD is crucial.
Purpose of the Study:
- Identify prognostic factors for pediatric epilepsy surgery in FCD.
- Analyze variables impacting seizure outcomes post-surgery for FCD.
Main Methods:
- Retrospective study of 149 pediatric patients with FCD and >2 years follow-up.
- Evaluation of 28 clinical, EEG, MRI, neuropsychological, surgical, and histopathologic parameters.
Main Results:
- Complete surgical resection is the sole significant predictor of epilepsy surgery success.
- Incomplete resection due to overlap with eloquent cortex leads to unfavorable outcomes.
- FCD type II, normal intelligence, and hemispherectomy showed non-significant trends toward better outcomes.
Conclusions:
- Complete excision of dysplastic cortex is the most critical factor for successful pediatric FCD epilepsy surgery.
- Accurate definition and complete resection of the FCD region are paramount for optimal seizure control.
Background:
Focal cortical dysplasia (FCD) is recognized as the major cause of focal intractable epilepsy in childhood. Various factors influencing postsurgical seizure outcome in pediatric patients with FCD have been reported.
Objective:
To analyze different variables in relation to seizure outcome in order to identify prognostic factors for selection of pediatric patients with FCD for epilepsy surgery.
Methods:
A cohort of 149 patients with histologically confirmed mild malformations of cortical development or FCD with at least 2 years of postoperative follow-up was retrospectively studied; 113 subjects had at least 5 years of postoperative follow-up. Twenty-eight clinical, EEG, MRI, neuropsychological, surgical, and histopathologic parameters were evaluated.
Results:
The only significant predictor of surgical success was completeness of surgical resection, defined as complete removal of the structural MRI lesion (if present) and the cortical region exhibiting prominent ictal and interictal abnormalities on intracranial EEG. Unfavorable surgical outcomes are mostly caused by overlap of dysplastic and eloquent cortical regions. There were nonsignificant trends toward better outcomes in patients with normal intelligence, after hemispherectomy and with FCD type II. Other factors such as age at seizure onset, duration of epilepsy, seizure frequency, associated pathologies including hippocampal sclerosis, extent of EEG and MRI abnormalities, as well as extent and localization of resections did not influence outcome. Twenty-five percent of patients changed Engel's class of seizure outcome after the second postoperative year.
Conclusions:
The ability to define and fully excise the entire region of dysplastic cortex is the most powerful variable influencing outcome in pediatric patients with focal cortical dysplasia.