Phase 3A: Follow-up research with GRID monitoring

In some cases, we need more information to determine whether epilepsy surgery is possible. We must precisely identify the location of the epileptic focus in the brain to see if a neurosurgeon can remove part of the brain in that area without affecting or damaging important brain functions. In Phase 3, two types of tests are involved. Your doctor will inform you about which test is applicable to you. For these tests, you will be admitted to MUMC+ for a procedure. This is special because the purpose of this surgery is not to treat, but to further diagnose.

During a GRID monitoring, a small grid with electrodes is placed on the brain during surgery. This allows us to observe a broader area of the brain, identifying what is located where and which functions are near the epileptic focus. Once the grid is placed, the recording begins. The goal is for you to have a seizure. In this test, the seizure must occur naturally. In previous tests, seizures are sometimes induced, but this doesn't always provide enough information about exactly where the seizure originates. We aim to find that with this test. Once we have enough seizures recorded, we stop the monitoring. This can take a few days or sometimes a few weeks. On average, it takes just under two weeks to gather sufficient information. You will be admitted to the Epilepsy Monitoring Unit (EMU) at MUMC+ during this time.

The removal of the grid placed on the brain is quite a significant surgery. If possible, we try to combine it with the surgery in Phase 4 to remove the source of the epilepsy, for those eligible for an epilepsy surgery.