What is a craniotomy
A craniotomy is an operation performed in order to treat various conditions affecting the brain.
It involves making an incision in the scalp and removing a window of bone from the skull (this bone is secured back in position at the end of the operation with titanium plates and screws). This allows access to the inside of the skull and brain.
What does stereotactic craniotomy mean?
Almost all craniotomies are performed with the assistance of computerized navigation techniques, also known as ‘stereotaxy’.
This is done order to reduce the size of the incision, by accurately localising the underlying problem, and increase the safety of surgery by avoiding important structures in the brain.
What this requires is a preoperative CT scan or MRI of the brain which is used by the Navigation system (like a GPS) making it possible for the surgeon to use a wand or a pointer to see exactly where the surgeon is in the brain, as depicted on the preop scan. This facilitates localisation and removal of the tumour.
What is a Craniectomy?
It involves making an incision in the scalp and removing a window of bone from the skull. This allows access to the skull and brain. When this bone is not replaced because of a variety of factors ( e.g. tumour involving the bone or a swollen brain following trauma or stroke), then the procedure is called a Craniectomy.
What are the types of tumour surgery?
A biopsy is the removal of a small piece of tumour tissue. This material is then examined under a microscope by an expert pathologist, and an accurate diagnosis is usually made.
Biopsies can be done as a “closed biopsy” or an “Open Biopsy” and both techniques relies on stereotaxy to localise the tumour.
During a closed biopsy operation, a small hole (‘burr hole’) is made in the skull using a high sped drill. A sample of tissue is obtained by passing a needle through this hole and into the tumour. This may be done under a general anaesthetic or local anaesthetic.
An open biopsy refers to a craniotomy. A craniotomy is performed before samples of the tumour are taken. In some situations this is safer than a closed biopsy.
Tumour excision VS Debulking surgery/partial excision
During a tumour excision procedure, the surgeon performs a craniotomy and then removes all (or almost all) of the tumour before replacing the skull and fixing the skin back in place using titanium plates and screws, tumour debulking (partial removal) is undertaken when it is unsafe to remove the entire tumour. Several features of the tumour may make it appropriate for debulking. For example, the tumour might be very close to, or even invading, critical structures, such as the speech area or blood vessels.
The decision to perform either a radical excision or a partial removal is not always black and white. It may depend upon a number of factors, including the neurosurgeon’s judgement and patient preference
What is an awake craniotomy?
An awake craniotomy is an operation performed in the same manner as a conventional craniotomy but with the patient awake during the procedure.
This is a preferred technique for operations to remove tumours close to or involving functionally important (eloquent) regions of the brain. Performing the operation in this way allows us to test regions of the brain before they are incised or removed and also to test the patient’s function continuously throughout the operation. The overall aim is to minimise the risks of the operation.
How is an awake craniotomy performed?
In the anaesthetic room you will have a drip inserted through which the anaesthetist will give you some drugs to make you feel comfortable and relaxed. In the operating theatre, your head will be stabilised using a brace. This brace has three pins that are applied to the skull. Prior to applying the pins local anaesthetic will be injected into the sites where the pins will be applied. The neuronavigation system will then be registered and used to mark out where the incision (cut) will be. Hair will be shaved along the line of the incision before it is cleaned with antiseptic solutions. Local anaesthetic will then be given around the incision. This will sting a little for a few seconds and then go numb.
We’ll then place some drapes around the area but you will be able to see the anaesthetic team and talk to them, and to move your arms and legs freely during the operation.
As the operation continues you will hear some noises and, briefly, a drilling sound.
When the brain is exposed we will perform a procedure called cortical mapping. This involves stimulating the brain surface with a tiny electrical probe. If we stimulate a motor region of the brain it may cause twitching of a limb or your face; a sensory area will cause a tingling feeling; the speech areas will prevent you from speaking very briefly. By mapping out the important regions of the brain first we can aim to avoid and protect them during the operation. Whilst we remove the tumour we will continuously test your function, and if anything changes we will be able to stop.
This does not eliminate the risks of surgery but does likely reduce them.
After the tumour has been removed, all bleeding is stopped and the dura (thick membrane surrounding the brain) is closed with sutures. The bone flap is replaced with mini-plates and the scalp is closed. The skin is then closed with staples and the wound is dressed and often a head bandage is applied.
What happens after awake surgery?
Post-operative recovery is generally much quicker than with a conventional craniotomy, as you will not have had a general anaesthetic. You will be able to eat, drink and move around (mobilise) as soon as you feel able to.
A postop CT scan of the brain is done on the day after surgery usually.
Discharge Instructions After Craniotomy
Whilst most patients will be discharged home after their surgery, some may benefit from a period of inpatient rehabilitation. You are encouraged to set a flexible plan for your recovery and should work slowly and steadily to increase your physical and mental tolerance.
During the first week at home, you should relax and just move around at home. Lifting anything over 5 to 10kgs, is discouraged for the first two or three months. Over the first few months after surgery, it is common to feel tired and you should rest frequently.
Your dressing will be removed a few days after surgery, and the staples are generally removed 7 days postop. You will be allowed to wash your hair without shampoo - by day 3 but would be required to keep wound dry after.
You can shower and gently wash your hair with shampoo by day 10 after surgery. Avoid hair products such as mousse or gels, as well as hair colourants and perms for at least 2 months after surgery.
Walking is the best exercise to undertake after brain surgery. Commence a walking program your second week home and increase the time and distance as each week passes. Aim for 1-2 hours per day on flat ground after two months.
You should avoid riding bicycles or running for at least two months. Other activities should be discussed.
You can resume sexual activity when you feel comfortable, but this should not be too vigorous for the first month or so after surgery.
Driving should be discussed with your neurosurgeon, as these guidelines vary from State to State, as well as from patient to patient.
The window of bone that was created to perform your operation has been secured in place with either small clamps or some plates and screws. These clamps or plates hold the bone fairly securely, but it usually takes up to 12 months for the bone window to fuse to the surrounding skull via growth of new bone across the narrow gap.
What Is “Normal” After A Tumour Craniotomy?
Headaches: these may be present to some degree and may persist for a number of weeks.
Numbness: this is common and arises because the skin nerves have been cut. The area of numbness usually decreases over weeks to months, but sometimes does not disappear completely.
Concentration: this is usually impaired for weeks to months after craniotomy. It is common to find difficulty focusing on certain tasks; you may need to re-read information in order to retain it. These symptoms tend to get better with time.
Emotional instability (lability): you may experience depression, crying spells, anxiety, and sensitivity to noise or people in crowded places. Try to relax and take it easy. Spend more quiet time.
Tiredness and What Is: these are very common, and gradually improve. Regular exercises tend to help overcome this sense of fatigue.
It can take up to 3 months before you feel “well” again. Have plenty of rest during the day and eat healthy foods. Do not drink more than a small amount of alcohol during this time. Get up at your regular time and get plenty of sleep. Your internal clock would have been altered during your hospitalisation, and it takes some time to return to normal.