A Craniotomy is a surgical procedure, where a portion of the skull is removed with a special cutting tool (craniotome) in order to gain access to the brain and it's surrounding structures. The resulting "bone flap" is usually replaced at the end of the procedure, secured with wires or reconstruction plates. In this fashion the patient is not left with a "soft spot" in the skull.

This procedure is used for resection of brain tumors, clipping of aneurysms, evacuation of cerebral hematomas and other lesions where a wider exposure is needed.

After a craniotomy has healed, avoidance of contact sports and the use of protective headgear in situations of increased exposure to head trauma is recommended.

MRI scans can be done after craniotomies, since the hardware (titanium) used is MRI compatible.  It also does not set off metal detectors.

A Craniectomy is a surgical procedure where a portion of the skull is removed, but not replaced. This is sometimes necessary in order to provide decompression of the brain. There are also times that a "bone flap" cannot be replaced, such as in cases of infection and trauma. In those instances patients are left with a "soft spot" in the skull which may require reconstruction with a "skull plate" (cranioplasty) at a later date .

This procedure is used when leaving "a soft spot" is acceptable  and making a "bone flap" is very difficult  (posterior fossa), when the bone is infected (osteomyelitis) or to provide decompression of the brain (malignant brain swelling, pseudotumor).

Protective headgear is recommended to protect the brain in situations where there is a risk of head trauma (falling tendency, uncontrolled seizures, non-contact sports, bicycling) and contact sports should be avoided.