So, DBS can be performed with the patient awake, meaning that at least through the critical part of the surgery we can test their movement and get them to do things to see if the DBS is optimally positioned. This is why they are kept awake rather than sleeping and sedated most of the time. The surgery can also be done while the patient is completely asleep. We decide based on the patient.
So for patients with a lot of anxiety as their main symptom, we recommend having it done asleep, whereas for patients who are fine being awake then the surgery will be done awake. Patients have told me that they were shocked that it was simple, they thought it would be really really complex, and it turns out to be simple.