A craniotomy is a type of brain surgery that includes opening the skull, most often to remove a brain tumor. The patient’s head is shaved for the procedure, and the surgeon cuts out a piece of bone from the skull in order to gain access to the brain. Once all or part of the tumor has been removed, the opening in the skull is covered, typically with the same piece of bone. Wire mesh or screw plates may be used to hold the bone in place, and the skin is closed with either stitches or staples.

If blood or fluid remain in the brain tissue, the surgeon may place a drain through one of the surgical openings. Typically, the drain is only in place for a few days.