A craniotomy is a surgical procedure for the removal of that part of the bone from the skull in order to expose the brain. Specialized tools are used to remove the bone flap, which is a part of the bone. The bone flap is temporarily removed, which is then replaced after the brain surgery has been done.

A craniotomy may be performed for the diagnosis, removal or treating of brain tumors. It can be done for the clipping or repairing of an aneurysm or the removal of blood or blood clots from a leaking blood vessel. It can also be performed for the removal of an arteriovenous malformation (AVM). Some other reasons why this procedure is performed are for the draining of a brain abscess, repairing a skull fracture, repairing a tear in the membrane lining of the brain, relieving of pressure within the brain, treatment of epilepsy and several other conditions related to the brain.

 A craniotomy is performed by a neurosurgeon assisted by a multi-disciplinary team of specialists of head-and-neck, otologic, oculoplastic and reconstructive surgeons.

Craniotomy can be classified into several types depending upon the location where the surgery is to be performed. The skull consists of the frontal bone located at the forehead,  the temporal bones located at the temples, the parietal bones on both the sides and the occipital bone at the back of the head.

• A frontal craniotomy is performed through the frontal bone
• A temporal craniotomy is performed through the temporal bone
• A parietal craniotomy is performed through the parietal bone
• An occipital craniotomy is performed through the occipital bone
• A pterional craniotomy is performed at the junction of the frontal, temporal, greater wing of sphenoid and parietal bones. 

Prior to your surgery, a thorough analysis of your medical history is done along with a physical examination. A consent form is taken requesting permission to conduct the procedure. Other diagnostic tests will also be prescribed to determine the right approach of treatment for your condition. A preoperative neurological examination is also conducted for comparative purposes. Any allergies or special conditions must be informed well prior to the surgery. You may be asked to fast before the surgery, generally, post-midnight. Based on your condition, your doctor may request any other conditions.

A craniotomy is a complex procedure which may last for around three to five steps. The entire procedure can be broadly categorized into five main steps  :

• Preparing the patient: The patient is administered with general anesthesia. Once asleep, the skull is placed in a 3-pin skull fixation device in order to hold the head in place for the surgery.
• Make a skin incision: Skin incisions on the scalp are made behind the hairline using a technique which spares the hair, where only one-fourth of the hair is shaved off.
• Perform the craniotomy by opening the skull: The skin and muscles are lifted off and folded back. Small burr holes are made with the help of a drill. The bone flap is replaced at the end of the surgery.
• Expose the brain: The dura is opened to expose the brain. Retractors may be used to gently open a corridor between the skull and the brain.
• Correction of the problem: Once the problem has been rectified, the dura is closed and the retractors are removed with sutures. The bone flap is put back into place and it is secured with titanium plates and screws.

After surgery, you will be taken to the recovery room where vital signs are monitored as you regain consciousness from anesthesia. The breathing tube will be placed until you fully recover from the anesthesia. You will then be moved to the neuroscience intensive care unit (NSICU) for close observation. Your response to various stimuli will be tested. Medication prescribed by your doctor will help in controlling these symptoms. Depending upon the type of brain surgery, steroid medication, and anticonvulsant medication may be given. The length of hospitalization varies according to your surgery and your complications.

Some of the complications arising due to this surgery, which are usually specific to certain parts of the brain are as follows:

• Memory problems
• Speech difficulty
• Paralysis
• Abnormal balance or coordination
• Coma

Some of the risks associated with craniotomy are :

• Infection
• Bleeding or blood clots
• Pneumonia
• Unstable blood pressure
• Seizures
• Muscle weakness
• Brain swelling
• Leakage of cerebrospinal fluid
• Risks associated with the use of general anesthesia

The results of this surgery are that the bony flap of the brain is replaced with titanium plates and screws.

A craniotomy surgery may cost five to six lakhs depending on the hospital amenities and type.