A burr
hole is a hole that is produced in a modern surgical procedure somewhat akin to
trepanning. A special
drill, with a rounded tip is used to carefully drill through the skull, until the brain is exposed.
The benefits of of having a burr hole include reduced pressure on the brain. Burr holes are often created as an emergency measure, when there is a build up of blood in the head, so that the blood can be drained. In cases in which there is a blood buildup at an unknown location, exploratory burr holes may be drilled to find the physical problem.
Another way in which burr holes are used is in the process of a craniostomy, in which part of the skull is removed. These form one of the earlier stages of the operation.