Craniectomy is a procedure in which part of the skull is removed to allow a swelling brain room to expand without being squeezed. It is performed on victims of traumatic brain injury and stroke. The surgeon marks a large square flap on the scalp that covers the surgical area with a felt tip pen. Following this mark, the surgeon makes an incision into the skin as far as the thin membrane covering the skull bone. Because the scalp is well supplied with blood, the surgeon will have to seal many small arteries. The surgeon then folds back a skin flap to expose the bone. Using a high speed hand drill or an automatic craniotome, the surgeon makes a circle of holes in the skull, and pushes a soft metal guide under the bone from one hole to the next. The surgeon saws through the bone until the bone flap can be removed to expose the brain.
After the surgery for the underlying cause is completed, the piece of skull is NOT replaced and the surgeon sutures the membrane, muscle, and skin of the scalp. The bone flap is frozen and stored in the bone bank for replacement in the future. It can be stored up to one year.