How a craniectomy is performed

During a craniectomy, a section of the skull is removed, but it's not replaced right away. This allows the brain room to swell without being squeezed.

A second surgery, called a cranioplasty, may be needed later to repair the skull. This involves replacing the missing bone with the original bone or with an artificial material. At Mayo Clinic, the neurosurgery and plastic surgery teams often work together when artificial materials are used to create a custom implant that fits the shape of the skull.

Cranioplasty typically is done after brain swelling has gone down, usually several weeks to months later.

After surgery, CT scans are used to check results. These scans show a visible area where the skull bone is missing.