Awake brain surgery, also called an awake craniotomy, is a type of brain surgery done while you are awake for part of the procedure. When you're awake, your care team can check how your brain is working. The surgery is most often used when a treatment involves areas of the brain that control important functions such as speech, movement and vision.

During this procedure, the surgical team may ask you to speak, move or respond to questions. This helps them monitor how your brain works in real time. It helps the team avoid damage to areas that are critical for everyday function.

Awake brain surgery is commonly used in some procedures to take out brain tumors. It also may be used in epilepsy surgery to help the care team understand how different parts of the brain function before removing tissue.

An important part of awake brain surgery is brain mapping. This involves gently stimulating small areas of the brain to find out what each area controls, such as language or movement. This process helps create a map of the brain. It helps the surgical team take out as much of the tumor or seizure area as possible while protecting important abilities, such as speaking, moving, seeing and understanding.

Even though you are awake for part of the procedure, your care team numbs your scalp and gives you medicine to help you stay comfortable. The brain itself does not feel pain, so you don't feel the mapping process.

There are different approaches and techniques used in awake brain surgery. Your care team chooses the best options based on your condition and the area of the brain being treated.

Awake craniotomy approaches

For some awake craniotomies, you may be asleep at the beginning and end of the surgery and awake during the middle part. In other instances, you may remain awake for most of the procedure.

You are usually awake when your care team needs to check brain function, such as during brain mapping. This allows them to ask you to speak, move or respond. When this testing is not needed, you may be given more medicine to help put you into a sleeplike state.

Your care team chooses the approach based on where the surgery is happening in your brain, the type of procedure, and what will keep you safest and most comfortable.

Brain mapping techniques

Your care team may map your brain during surgery by gently stimulating areas of the brain to see how they affect movement, speech and other functions. In some cases, the team also may do mapping before surgery using special tests.

Brain mapping can be done during surgery or, sometimes, before surgery using electrodes placed on or in the brain.

Imaging and navigation tools

Your surgical team may use detailed imaging, such as MRI or computer-guided systems, to help guide the surgery and improve accuracy.

One example is frameless stereotaxy. This is a type of navigation system that uses MRI or CT scans to create a 3D map of the brain. It helps the surgeon find the exact location of the tumor or seizure area and improves accuracy during surgery.

Awake brain surgery is used when a tumor or an area causing seizures is close to parts of the brain that control important abilities, such as speaking, moving and understanding. The surgical team needs to remove or treat the area while protecting these functions.

Before surgery, imaging tests can show where a tumor or seizure area is located. But they cannot always show exactly where important functions happen in each person's brain. These areas can vary from person to person, especially when a tumor or seizures have changed how the brain works.

Awake brain surgery allows the surgical team to check brain function in real time during the procedure. Using brain mapping and asking you to speak, move or respond, the team can find which areas control key abilities and avoid them during surgery.

Brain mapping finds areas of the brain that control functions such as language, movement, sensation and vision. It is not always needed but is usually used when the area being treated is close to areas that control these functions.

This approach helps the surgical team take out as much of the tumor or seizure area as possible while lowering the risk of trouble with speech, movement or other important functions after surgery.

Awake brain surgery has many of the same risks as other types of brain surgery. These risks can vary depending on where in the brain the surgery takes place and what condition is being treated.

Possible risks include general surgical risks, changes in brain function and other possible risks.

General surgical risks

• Bleeding.
• Infection.
• Swelling in the brain.
• Buildup of fluid in the brain.
• Spinal fluid leaks.

Changes in brain function

• Trouble with speech or understanding.
• Weakness or trouble moving.
• Changes in vision.
• Memory problems.
• Trouble with balance or coordination.

Other possible risks

• Seizures.
• Stroke.
• Meningitis.

Because different parts of the brain control different functions, the type of risk depends on the area being treated. Awake brain surgery is often used to help lower the risk of damage by allowing the surgical team to monitor brain function during the procedure. However, risks cannot be completely avoided.

Before surgery

Your care team decides whether awake brain surgery is the right option for you. The team explains the procedure, including the benefits and possible risks, and answers your questions.

You may have tests to help plan the surgery. These can include imaging tests, such as MRI, and other evaluations to understand how different areas of your brain work.

Before the procedure, you also may meet with a specialist such as a speech or language expert. This healthcare professional may ask you to name pictures, read words or complete simple tasks. You practice these activities ahead of time so your care team can check your responses during surgery.

Your care team gives you instructions on how to prepare. This may include when to stop eating and drinking, how to take your usual medicines, and what to bring to the hospital.

You also may talk with your care team about what to expect during the surgery, including how you will stay comfortable and how you will be asked to respond during brain mapping.

During surgery

You receive medicine to help you relax and stay comfortable. Your care team numbs your scalp so you do not feel pain. You may be sleepy during parts of the surgery and awake during others, depending on when your care team needs to check your brain function.

Even though you are awake for part of the surgery, you should not feel pain. The brain itself does not feel pain. You may feel pressure or a sense of pulling during parts of the procedure, but your care team gives you medicine to help you stay comfortable.

Awake brain surgery often takes several hours. Brain mapping may last from about one hour to several hours depending on the area being tested.

Your head is gently held in place to keep it still. Part of your hair may be clipped. The surgeon then makes an opening in the skull to reach the brain.

If the surgery involves areas that control important abilities, your care team performs brain mapping. This helps identify which parts of your brain control functions such as speaking, movement and vision.

During mapping, the surgeon gently stimulates small areas of your brain and watches how your body responds. You may be asked to speak, count, look at pictures or move part of your body.

The stimulation is not painful, but it may cause brief changes in your abilities. For example, you might have trouble speaking, notice movement in a body part or have a tingling feeling. These effects stop right away when the stimulation ends.

You also may hear sounds from equipment or feel your head being held in place. But your care team guides you through each step.

Your care team also uses detailed brain imaging, such as MRI or computer-guided tools, to help guide the surgery.

Throughout the procedure, your care team closely watches your brain and body function. If the team notices any changes, the surgeon can pause, move to a different area or change the plan to help protect important abilities, such as speaking, moving, seeing or understanding.

After surgery

After surgery, your care team closely monitors you as you wake up. Many people spend some time in an intensive care unit before moving to a regular hospital room. You will likely stay in the hospital for a few days, often about 2 to 3 days. This allows your care team to watch you carefully as you recover.

Your care team may order an MRI to check how much of the tumor or seizure area was taken out.

It is common to feel tired or have some discomfort as you recover. Your care team helps you manage pain and watches for any changes in how your brain and body are working.

Most people can slowly return to typical activities over several weeks to a few months. You have follow-up appointments to check your recovery and plan next steps in your care.

You also may need physical, speech or occupational therapy depending on your recovery.

Results can vary depending on the reason for surgery and the area of the brain involved.

When people have surgery for epilepsy, many of them have fewer seizures after surgery. Some people become seizure-free. Others may still have seizures but less often. Sometimes, seizures may not change.

If you had surgery to take out a tumor, the goal is to take out as much of the tumor as safely as possible while protecting important abilities. You may still need other treatments, such as radiation therapy or chemotherapy, to treat any remaining tumor cells.

After surgery, your care team continues to monitor your condition and adjust your treatment plan as needed. Recovery and long-term results depend on your specific condition and how your brain heals.