So one of the most common type of epilepsy surgery is resective surgery. So that's where we find out where the seizures come from in the brain. So first we will do a routine EEG, then we will do a video EEG which is a more extended EEG that lasts for several days so we can see exactly where on the brain the seizures are coming from or on the skull where that seizures are coming from. Once we've decided which side they are coming from and which area, we are going to the next step. In the next step we would say okay its time to have the epilepsy surgery we know the seizures come from one side of the brain and this is where the neurosurgeon will open up the skull, places the electrodes directly on the brain, then we will put the skull back on, wrap the patient up, wake the patient up, put them in the ICU, and let them have seizures; we capture a bunch of seizures using our computers and our fancy electrodes to help mark out where the seizures are coming from, what exactly, which gyri, which electrodes are the seizures coming from. Once we know where the seizures are coming from we can then go back and tickle each electrode to make sure that is not important area, it does not control an arm, a leg, speech. Once we know that the area is safe to resect then the neurosurgeon go in with the area that we allocated, where the seizures are coming from, take it out safely, and hopefully cure the epilepsy. So what we do is when we put them on we cover the area that we think the seizures are most likely to come from. But you can cover almost the whole side of the brain. You can cover underneath, under the temporal lobe, and you can cover between the two hemispheres that ou get really good localization and you feel really confident about the area where the seizures comes from, and equally as confident that you are not going to take anything out that's very important. So epilepsy surgery, resective surgery, the goal is to define which lobe it is coming from, use the grids and the strips to basically in a three dimensional manner, localize out which gyri where exactly is coming from, and double check that you are not taking out any important territory you need to exist with, right to talk and walk and your arms, and create that safety margin and then to get the best cure to stopping the seizures from happening, and that's what a resection surgery is.