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 lesions close to, or involving, eloquent (functionally important) regions of the brain. This allows us to test regions of the brain before they are incised or removed and allows us to test patient's function continuously throughout the operation. The overall aim is to minimise the risks of such operations.
There are different techniques but the most commonly used here is described. In the anaesthetic room you will have a drip inserted with some drugs that make you feel comfortable and relaxed. In theatre, the neuronavigation system will then be used (as previously described) to mark out the incision and a very small amount of hair shaved along the line of the incision before it is cleaned with antiseptic solutions and then local anaesthetic is inserted around the incision. This will sting a little for a few seconds and then go numb.
We will then place some drapes around the wound but you will be able to see the anaesthetic team and talk to them and be able to move your arms and legs freely during the operation. The operation then continues and you will hear some noises and the drilling sound briefly.
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, the dura is closed with sutures, the bone is replaced with 3 mini-plates and the scalp is closed. The skin is closed with staples, the wound is dressed and often a head bandage is applied.
Post-operative recovery is generally much quicker as you will not have had a general anaesthetic. You will likely only have a single drip and will not have any other lines or a catheter. You can eat, drink and mobilise as soon as you feel able to and will be able to be discharged on the same day as your operation or the following day if you are able. If you are having day-case surgery you will need a CT scan of the head 4 hours after surgery and can be discharged 6 hours post-op provided all is well.
After any major operation it takes a few weeks to recover fully. For the first couple of weeks you may have some headaches that you should be able to control with simple painkillers that you will be given. You will feel more tired than usual and will need to rest when you feel tired. However, you should do a little more simple exercise each day such as taking walks.
Your surgeon will usually arrange to see you in the outpatient's clinic about 5 to 7 days after surgery to check on your recovery and also to give you any results from biopsies from the operation. He will also advise you on your further care and answer any other questions that you have. Your clips or stitches will probably be removed in the clinic too.
The risks of awake surgery for a brain tumour are the same as those for conventional surgery but there is also a small risk of seizures during surgery that might require conversion to general anaesthetic in rare circumstances.
Every operation carries a risk. Overall, complications following a craniotomy are uncommon and the degree of risk depends on a number of factors, for example, the size, location and type of the tumour, your general medical health and age. Your surgeon will explain to you the particular risks associated with your operation and give you an indication of the likely chance of complications occurring. Complications include, but are not exclusive to, the following:
Some of these complications might be serious enough to warrant further surgery and some can be life threatening. Overall, as a general guide, the incidence of serious complications causing permanent neurological deficit (stroke) or death is less than 5%.
Overall the risks of general complications of surgery, such as deep vein thrombosis and urinary or chest infection, are thought to occur less frequently because you will not have a general anaesthetic.