Skip to 0 minutes and 13 seconds Dr. Absalom talked you through the steps of finishing up a successful surgery, but let’s go back for a moment to what the clinical neurophysiology is taking care of during the whole procedure. When we stimulate a brain, it is important to see how the brain reacts on that. More explicitly, firstly, we want to prevent that an epileptic seizure occurs. The other reason to measure electrical activity of the brain in mapping procedure is to detect afterdischarges. After discharges are local epileptic phenomena that may occur after ending the four-second stimulation. They interfere with the correct interpretation of language testing. The surgeon is informed when they occur. He knows not to base his decision on them. [DUTCH] This is a hatstand.
Skip to 1 minute and 14 seconds This is a chameleol [SIC] Phonological paraphrase.
Skip to 1 minute and 21 seconds This is a mask.
Skip to 1 minute and 27 seconds We monitor the electrical brain activity but putting a strip electrode on the brain in the proximity of the stimulation.
Skip to 1 minute and 44 seconds This is what I see on my monitor. The broad lines on the left show the activity due to electrical stimulation. Directly after that, normal brain activity resumes. This is a technically good stimulation without after discharges. They occur if the stimulation intensity is too high, but sometimes after discharges appear without any apparent reason. This is an example of epileptic activity after stimulation. These sharp slow waves are typical for that. When this phenomenon does not disappear after a few seconds. The neurosurgeons sprays ice water on the epileptic brain area to avoid a seizure. Often, we can continue mapping after that. Nowadays, before surgery, we give a low-dose of anti-epileptic drugs to prevent epileptic activity.
Skip to 2 minutes and 48 seconds Most seizures appear in the face of stimulation on the still open brain. However, here we have a clip of what happened with our patient.
Skip to 3 minutes and 18 seconds In this rare case, the epileptic seizure occurred directly after surgery. Because the wound was already closed, we could not use ice water. Therefore, we used anti-epileptic drugs to stop the epileptic attack. You can see the surgical team reacting immediately to ensure the patient is stabilised as fast as possible. He woke up after the surgery without any major effects of the seizure.
Seizures and other complications
Complications can occur during different stages of an operation. In this video, we can observe how the surgical team deals with them during an awake brain surgery.
Warning - viewer discretion is advised. This video contains moving images of open brain surgery. This may be upsetting to some people.
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