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. Then 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 )
• Abnormal blood vessels (arteriovenous malformations; AVM)
• 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
• Some forms of seizure disorders (epilepsy )

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 on the disease being treated, the person's general health, the extent of the procedure, and the surgical techniques used.

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