What is focal resection?
Focal resection is surgery to remove the section of the brain responsible for seizures, usually the temporal lobe. Focal resection can be done in children who do not respond to anti-seizure medications if the child’s seizures begin in a single area of the brain.
Why it's done
If a child has a lesion on the MRI and has medically refractory epilepsy, there are high chances of seizure freedom or great reduction in seizures if a resection can be performed. Even in the absence of a brain MRI abnormality, our epileptologists can use other techniques to determine the epileptogenic zone. A complex and multimodality patient selection process ensures the best chance of seizure-free outcomes.
We understand that deciding on brain surgery to treat your child’s epilepsy is not easy. At Cohen Children's, we work closely with you to ensure the best course of treatment for your child. Our epilepsy and neurosurgery team will do an extensive work-up to determine the type of surgery that is necessary. These tests could include:
- Inpatient video EEG monitoring with guided withdrawal of anti-seizure medications to induce and localize patient’s seizures
- 3T magnetic resonance imaging (MRI) with a specialized epilepsy protocol and volumetric studies in select cases
- FDG PET scan
- Neuropsychologic testing
- WADA test
- Functional MRI
- Diffusion tensor imaging
- Visual field evaluations
- MEG study (performed at a collaborating institution)
All the data is then analyzed and presented at our multidisciplinary conference attended by many epileptologists, neuroradiologists, neuropsychologists and neurosurgeons. A consensus as to the best treatment option is reached at this meeting. We specialize in focal resection as a surgical treatment for epilepsy in children, so if this is needed, rest assured your child is in good hands.
Types of focal resections
Single stage focal resections or “lesionectomy”
Based on the findings on the MRI, video EEG and other tests, the team may decide on a single stage resection. An epileptologist often guides the resection using a technique called ECOG (electrocorticography) in the operating room (OR). A thin grid of electrodes is placed directly on the cortical surface, and intracranial EEG monitoring is done before and after the resection of the lesion.
Two-stage focal resection
In the MRI negative cases, the epileptologist may still highly suspect a focal onset based on the non-invasive tests. In these cases, a second stage is needed. The child is taken to the OR and an array of intracranial electrodes is placed either as a combination of strips, grids and depth electrodes or as sEEG (stereo EEG) with the assistance of a highly specialized robotic technique (ROSA). Seizures are captured in a monitored setting in the pediatric ICU and bedside functional mapping (extra-operative cortical mapping) is done to assess if the areas involved in seizure generation also harbor important functions like speech/motor movement. The patient is taken back to the OR to resect the epileptogenic zone.
After undergoing a focal resection, anti-seizure medications will be continued and your child’s epileptologist will decide if and when to decrease the medications. A seizure in the immediate postoperative period usually does not suggest failure of the surgery. The child will be followed closely by our experts as an outpatient until surgical recovery is complete. A second set of neuropsychologic tests will be done six months after the surgery.