A decompressive craniectomy is a surgical procedure that removes a part of the skull, which will be replaced at a later date. Once the patient’s brain swelling has subsided and no other complications have developed, then cranioplasty can be performed whereby either the original piece of bone that had been removed and freeze-stored can be put back in place, or an artificial plate may be attached. 

The goal is to relieve pressure in the brain and allow a swollen brain enough room to expand without causing any further damage. Increased intracranial pressure could cause brain herniation which then compromises cerebral blood flow, which can be fatal. This procedure is sometimes performed on victims of traumatic brain injury or for those who have had a massive stroke.