Beginning
- The first thing to understand about an awake craniotomy is that you are not awake the whole time. In fact, you will be asleep for the first 1-2 hours and again at the end of the operation.
- Before starting the operation the doctor gives a local anesthetic to numb your scalp. The numbing medicine acts quickly, but lasts a long time. As a result, your scalp remains numb throughout the entire operation
- After numbing the scalp, an incision is made through the skin and underlying tissues to expose the bone. While you continue to sleep, a small area of bone (a bone flap) is removed.
Removal of bone flap
- After removing the bone flap, the doctor can actually see the brain which is now visible under a protective layer of membrane. The membrane is opened, very carefully, to expose the brain. By now, you will have been asleep for 1 to 2 hours.
- Once the membrane has been opened you will be awakened.
Awakening
- Upon awakening you will not be disoriented or confused. Your first awareness will be that of hearing someone calling your name.
- You will not be able to turn or lift your head because it is held securely in place by a specially designed head holder. When you open your eyes, you will see only a paper sheet lying close to your face. Gradually, you begin to realize that you are waking-up during your surgery and you feel no pain.
- Unlike TV, a real operating room is a noisy place with a number of people talking at once. Do not be alarmed by any of the noises you hear. Instead, listen for the voice of the neuropsychologist. He or she will call your name repeatedly until you are fully awake. Although you will not be able to move your head or see very much, you will be able to talk. It is important that you speak to the neuropsychologist. Let him know when you are awake and how you are feeling.
- He will stay with you throughout the awake portion of the operation to monitor your speech, your movement, and the quality of your thinking. Your operation will not go forward until the neuropsychologist has made certain that you are fully awake, comfortable, and able to cooperate. The next step in your operation is functional mapping.
Functional Mapping
- The purpose of functional mapping is to determine whether boundaries of the operative area overlap or interfere with areas of the brain that support important functions such as speech and movement.
- Functional mapping is done by stimulating the brain with a small electrical charge. Since the brain itself has no pain receptors, you should not experience pain or headache from the stimulation.
- During the mapping procedure, the neuropsychologist monitors your speech, your movement, and your awareness of sensations. He will ask you to report any unusual sensations. The mapping procedure usually takes 20 to 30 minutes to complete.
