The hair on part of the scalp is shaved. The scalp is cleansed and prepared for surgery. An incision is made through the scalp and a hole is drilled through the skull. A piece of the skull is removed (usually temporarily) and the surgery is performed, after which the bone is replaced and secured in place.

Brain surgery may be needed to treat:

• brain tumors
• bleeding (hemorrhage) or blood clots (hematomas) from injuries (subdural hematoma or epidural hematomas)
• weaknesses in blood vessels (cerebral aneurysms)
• arteriovenous malformations (AVM; abnormal blood vessels)
• damage to tissues covering the brain (dura)
• pockets of infection in the brain (brain abscesses)
• severe nerve or facial pain (such as trigeminal neuralgia or tic douloureux)
• trauma to the skull and repair of skull fractures

Risks for any anesthesia are:

• reactions to medications
• problems breathing

• bleeding
• infection

• injury to brain tissue
• injury to blood vessels
• nerve or muscle paralysis or weakness
• loss of mental functions (memory, speech, understanding)

The results depend greatly on the underlying disease being treated, the general health of the patient, the extent of the procedure and the surgical techniques employed.

The recovery time varies from 1 to 4 weeks. Full recovery may take up to 8 weeks.