A craniotomy is a surgical procedure to remove a section of bone (bone flap) from the skull to provide access to the brain. The bone flap is then replaced at the end of the procedure. A craniotomy is the main treatment for subdural hematomas that happen after a traumatic skull injury. Other conditions, like intracranial hypertension, sometimes call for this procedure.
Cranionotomies are done in order to:
-Diagnose or remove brain tumors.
-Clip or repair aneurysms.
-Remove blood or blood clots from a leaking blood vessel under the skull.
-Remove an arteriovenous malformation (AVM).
-Drain brain abscesses.
-Repair a tear in the membrane lining the brain.
-Relieve intracranial pressure by removing damaged or swollen areas of the brain caused by traumatic injury or stroke.
The procedure may vary from one person to another, depending on the condition treated. Craniotomy is generally performed under general anesthesia. The surgeon will make an incision (cut) in the scalp, a skin flap is peeled back, burr holes are drilled in the skull, and then a piece of bone (“bone flap”) is cut out to reveal the brain underneath. The bone flap will be removed and saved. The thick outer covering of the brain directly underneath the bone (dura mater) will be separated from the bone and carefully cut to open it to expose the brain, securing it with retractors. Once the brain surgery is performed, the retractors are removed and the dura is closed with sutures. The bone flap is replaced and secured with plates and screws, which remain permanently to provide support. The muscles and skin are replaced and sutured; a drain may be inserted to prevent fluid retention. A soft adhesive bandage is placed over the incision. The procedure may take about 4-6 hours. After the completion of the procedure, patients will be taken to the recovery room wherein their vital signs will be clearly monitored. Depending on the type of surgery performed, patients may be given steroid medications (to control swelling) and anticonvulsant medications (to prevent seizures).
The surgeon and anaesthetist will ask you about your general health and any medical conditions that could increase the risks of surgery before deciding when to do the operation. The operation is usually carried out under a general anaesthetic which means you will be asleep throughout the procedure. A small horseshoe-shaped area of your scalp is shaved over the point at which the surgeon needs to operate.
Immediately after the procedure, patients will be taken to a recovery room for observation before being taken to the intensive care unit (ICU) to be closely monitored. Medications will be given to reduce swelling. The recovery period will vary depending upon the type of procedure done and the type of anesthesia given. However, it is important for patients to carefully follow the recovery guidelines. Most patients are instructed to avoid engaging in strenuous activities, consuming alcohol and tobacco products and driving until cleared for these activities by their treatment team.
As any surgical procedure will have its own set of complications, brain surgery risk may depend upon the specific location of the brain that the operation will affect. Some of the general complications include – bleeding, infection of the lungs (pneumonia), unstable blood pressure, seizures, muscle weakness, leakage of the cerebrospinal fluid, brain swelling, blood clots and the risks of general anesthesia. In addition, there may be some other rare complications like – memory problems, paralysis, speech difficulty, coma and abnormal balance or coordination that directly relate to the specific places in the brain.
What are the different types of craniotomies?
There are different types of craniotomies that vary in size and complexity and these include: 1.Extended bi-frontal craniotomy – This is a traditional skull base approach used to target difficult tumors toward the front of the brain. 2.Minimally invasive supra-orbital “Eyebrow” craniotomy – In this type, neurosurgeons make a small incision within the eyebrow to access tumors in the front of the brain or pituitary tumors. This minimally-invasive procedure may be part of the treatment for Rathke’s cleft cysts, skull base tumors and some pituitary tumors. 3. Retro-Sigmoid “Keyhole” craniotomy – Neurosurgeons may use this approach to remove tumors like meningiomas and acoustic neuromas (vestibular schwannomas). 4. Orbitozygomatic craniotomy – This type is typically used to treat lesions that are too complex for removal by more minimally invasive approaches. 5. Translabyrinthine craniotomy–This procedure involves making an incision in the scalp behind the ear, then removing the mastoid bone and some of the inner ear bone (specifically the semicircular canals which contain receptors for balance).
What Is the Difference Between a Craniotomy and a Craniectomy?
Craniotomy: During this procedure: a small piece of skull is removed so that a surgeon can access the brain. Once the tumor has been removed, the bone fragment is put back in place. Sometimes, the bone fragment is secured with small plates or screws, and heals like a bone fracture. Craniectomy : A craniectomy is a surgical procedure that is very similar to a craniotomy, but with one key difference. After a craniectomy, the bone fragment is not immediately put back into place. This approach may be taken if there is significant swelling in the brain and a surgeon deems it necessary to relieve pressure within the skull. The bone fragment is typically kept so that it can be put back into place during a future surgery, although it may also be discarded in favor of a future reconstruction using an artificial bone.