Brain biopsy

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A brain biopsy is a procedure used to remove a very small piece of tissue from the brain, so it can be examined under a microscope. The tissue sample helps diagnose the condition that is affecting the brain. It also helps guide decisions about next steps in care.

Brain biopsies are most often used when imaging tests such as brain MRI or brain CT scans show an area that cannot be clearly identified based on images alone. In many cases, a biopsy is the most reliable way to tell whether a brain lesion is a tumor, an infection, inflammation or another condition.

Most brain biopsies today are stereotactic needle biopsies. This method combines brain imaging with computer tools to help guide the biopsy needle to the right spot. The biopsy is usually done through a small opening in the skull using a needle to remove tiny tissue samples.

In some situations, a larger piece of skull is removed. This technique, called an open biopsy, may be done when part or all of a tumor may need to be removed with surgical tools or when a larger sample is needed for diagnosis.

A brain biopsy is used to diagnose a condition, not to treat it. Its purpose is to provide information that helps the care team choose the right care plan based on the biopsy results.

Most people need to stay in the hospital for at least one night after a brain biopsy, so they can be carefully monitored as they recover. A stereotactic brain biopsy usually requires an overnight hospital stay. But some people may be discharged on the same day of the procedure depending on individual factors, such as age and overall health.

Types

There are different ways to perform a brain biopsy. The approach depends on the location of the lesion, how much tissue is needed and whether a small sample is enough to make a diagnosis. Two common types are stereotactic biopsy and open biopsy.

Stereotactic brain biopsy

A stereotactic brain biopsy involves a small opening in the skull and a needle to remove the sample. This type of brain biopsy also uses MRI or CT imaging along with computer guidance to help the care team target a specific area of the brain with high accuracy. Stereotactic refers to the use of imaging and computer guidance to map the brain in 3D and guide the biopsy needle to a precise location.

A small opening is made in the skull, and a needle is guided to the area of concern to remove tiny tissue samples. This is sometimes referred to as a needle biopsy.

Stereotactic biopsies may be done using a head frame or with a frameless system that uses markers placed on the scalp. Frameless biopsies are most common. Both methods are designed to help the surgeon reach the exact area being sampled while reducing the risk of damage to nearby brain tissue.

Open (surgical) biopsy

An open biopsy, also called a surgical biopsy, is done as part of a surgery in which a larger opening is made in the skull. This surgery is called a craniotomy. It allows the neurosurgeon to directly access the brain by removing a piece of the skull. The tissue sample is then removed using specialized surgical tools.

An open biopsy also may be performed during a surgery for another purpose, such as removing part or all of a tumor.

How stereotactic biopsy differs from open biopsy

Stereotactic biopsy is typically used when:

• The main goal is to make a diagnosis.
• A lesion is deep in the brain or near critical structures.
• A less invasive approach is preferred.
• An open biopsy or removing more tissue would carry higher risk.

Open biopsy is usually used when:

• A larger sample of tissue is needed to make the diagnosis.
• Removing part or all of the lesion may help relieve symptoms or pressure.
• Tissue removed during surgery also can confirm the diagnosis.
• The lesion is not located in a deep area of the brain or near parts of the brain that control important functions, such as movement, speech or vision.

لماذا يتم ذلك؟

A brain biopsy is done to help identify the cause of a changed area in the brain when imaging tests alone cannot provide a clear answer. The tissue sample allows specialists to examine cells under a microscope and possibly run more tests that help figure out what is causing your symptoms.

Brain biopsies are most often used to:

• Confirm whether a brain lesion is a tumor and determine the tumor type.
• Determine if a change in a brain lesion found on MRI after tumor treatment is caused by a tumor growing back or changes in the brain caused by treatment.
• Help rule out cancer when other conditions look similar on imaging. This may include infections or inflammation, or conditions where the immune system damages the brain's protective covering around nerve cells.
• Help guide decisions about next steps in care, including whether surgery, medicine or other treatments may be helpful.

A brain biopsy is not typically used to diagnose neurodegenerative conditions such as Alzheimer's disease or other types of dementia. These conditions are usually diagnosed based on symptoms, imaging and other tests. In rare situations, a brain biopsy may be considered to help rule out other possible causes of cognitive symptoms, such as a tumor or inflammation, when test results are not clear.

When a lesion is located in a deep or sensitive area of the brain, stereotactic biopsy is often done because open surgery would carry higher risk. In these cases, stereotactic biopsy allows the care team to make or rule out a diagnosis without removing a larger amount of tissue.

المخاطر

A brain biopsy is generally safe. Like any procedure involving the brain, it does carry some risk. Most of these risks are not common, and serious risks are rare. Before recommending a biopsy, the care team carefully weighs these risks against the value of getting clear answers.

• Bleeding in the brain. Bleeding at the biopsy site is the most common risk of a brain biopsy. In many cases, bleeding is small and does not cause symptoms. This type of bleeding may only be seen on imaging tests. Heavy bleeding or bleeding that causes symptoms is less common.
• New or temporary neurological symptoms. Some people experience new neurological symptoms after a brain biopsy. These may include weakness, changes in speech or sensation, or confusion. These symptoms are often temporary and get better over time. Permanent neurological symptoms like these are not common.
• Brain swelling (edema). This can happen because the biopsy needle or surgery irritates brain tissue or small blood vessels, leading to temporary swelling. Brain swelling can increase pressure and may cause symptoms such as headache, weakness or confusion. In most cases, the swelling is temporary and improves with time and treatment of the underlying condition.
• Seizures. Seizures can occur after a brain biopsy, but they aren't common. When they occur, seizures are brief. They are not likely to result in permanent injury of the brain and can usually be managed with medicine.
• Infection. Infection at the biopsy site or within the brain is possible but rare. If an infection occurs, it is treated with antibiotics. In rare cases, more procedures may be needed to treat the infection.

Risks related to lesion location

The risk of complications can vary depending on where in the brain the biopsy is performed. Biopsies of deep or sensitive areas of the brain may carry a higher risk of neurological symptoms after the procedure than biopsies of areas that are easier to reach safely. Stereotactic brain biopsy techniques are designed to limit risk while allowing surgeons to reach the brain tissue needed for a sample.

Can a brain biopsy be fatal?

Death related to a brain biopsy is very rare. Large studies show that the risk of death from this procedure is low. While statistics are different based on factors such as biopsy type and overall health, fewer than 1% overall die as a result of a brain biopsy.

كيف تستعد؟

Getting ready for a brain biopsy may take several weeks. During this time, the care team works with you to plan the safest approach, help you get ready physically and make sure you know what to expect.

Medical visits and planning

You likely will meet with members of the care team to review your medical history, symptoms and imaging studies. Brain MRI or brain CT scans are often used to help plan the biopsy and determine the safest path and biopsy type to the area being sampled. In some cases, you may have more tests or visits with other specialists before the procedure.

Medicines, supplements and health conditions

The care team reviews all medicines you take, including prescription drugs, over-the-counter medicines, and herbal or alternative supplements. Some medicines that affect bleeding or healing may need to be adjusted ahead of time. Your care team also discusses any long-term health conditions you have, such as diabetes, heart disease or seizure conditions. Team members tell you whether any changes to your regular routine or extra steps are needed to reduce the risk of complications from a brain biopsy.

Diet and activity

In the weeks leading up to a brain biopsy, eating a balanced diet and staying active within your usual routine can help support overall health. The care team tells you if any specific diet or activity changes are recommended ahead of time.

Work, school and transportation planning

Planning ahead is important even when a brain biopsy is done as an outpatient procedure and you can go home the same day. If you know that your brain biopsy requires a hospital stay, you may need to make arrangements at home. You may need to arrange time off from work or school and plan for transportation, especially if you are not able to drive right away after the procedure. Thinking through these details in advance can help reduce stress.

Support and practical considerations

You may be encouraged to bring a family member or support person to appointments before the biopsy and on the day of the procedure. It also can be helpful to prepare a list of questions and bring that and important information, such as your medicine list and insurance details, to preprocedure visits.

ما يمكن أن تتوقعه

A brain biopsy usually follows a similar set of steps at most hospitals and during early recovery. While some details may vary, understanding what typically happens before, during and after the procedure can help you feel more prepared and at ease.

Before

When you arrive, you may be asked to change into a hospital gown and remove personal items, such as jewelry. Members of the care team review your information, answer questions and explain what happens during a brain biopsy.

Imaging such as MRI and CT and navigation tools are used to confirm the exact location of the area being biopsied. Your head may be gently secured in a frame so it stays still during the procedure.

During

You may have a small needle placed in a vein in your arm to give medicine that helps you relax or puts you into a sleeplike state. The type of medicine used depends on the type of biopsy and what is safest for you.

Even if you are not fully asleep, medicine helps keep you comfortable. The care team monitors you closely the entire time.

The procedure usually takes about 1 to 2 hours, though the exact length can vary. What happens during the brain biopsy depends on the type of procedure you have:

• If you are having a stereotactic brain biopsy. For a stereotactic biopsy, the goal is to collect a small tissue sample using precise imaging guidance. To help the surgeon target the correct area, your head must stay very still.

  In some cases, a frame is attached to your head. The frame is secured to the skull using small pins after the scalp is numbed with medicine. The frame does not go into the brain. It helps keep the head in the same position so imaging and computer guidance stay accurate. Some stereotactic biopsies use frameless systems, which rely on small markers placed on the scalp instead of a frame.

  A small area of hair may be trimmed. The surgeon then makes a small opening in the skull and uses MRI or CT imaging with computer guidance to carefully guide a needle to the target area. Tiny tissue samples are collected, and the needle is removed. These steps are carefully planned to help protect nearby brain tissue.

• If you are having an open biopsy. If an open, also called surgical, biopsy is planned, a small piece of the skull is removed during a procedure called a craniotomy to allow direct access to the brain. This approach may be used when part or all of a lesion is being removed. The tissue sample is taken using specialized surgical tools and then studied in a lab to help diagnose or rule out a condition.

  Once the tissue sample is removed, the surgeon replaces the piece of the skull and closes the opening in your scalp. As you recover, the skull and the skin heal well. There is no weakened area of the skull after this procedure.

• Comfort during the procedure. The biopsy itself is not painful. You may feel pressure or brief sensations related to positioning or equipment but no pain. Surgical team members give you medicine to keep you comfortable. You may be given medicine for pain or medicine to help you relax or to keep you in a sleeplike state, called an anesthetic. Tell the care team if you feel any discomfort at any time.

After

After the brain biopsy, you are taken to a recovery area and monitored while the effects of the medicines used to help you relax or keep you in a sleeplike state wear off. You may feel sleepy or have mild soreness near the biopsy site or where the frame was attached to your head. Some people notice temporary changes such as a headache or fatigue, which usually get better over time. A small bandage covers the biopsy site.

Some people go home the same day, while others stay overnight for observation. You should plan to have someone to drive you from the hospital and help you get settled at home.

Your healthcare team tells you when it's safe to get back to your regular activities. This may depend on how you feel and the type of biopsy you had. You may need to limit certain activities, such as strenuous activity, heavy lifting or exercise. Your care team gives you specific instructions about activity limits and when it is safe to resume work, driving and exercise.

النتائج

Brain biopsy results describe what was found in the tissue sample taken from the brain. These results help diagnose the condition causing your symptoms and guide decisions about next steps in care.

Results are not available right away. The tissue sample needs careful study, and final results are usually ready within several days to several weeks. A member of the care team reviews the results with you, explains what they mean for you and discusses next steps. Writing down questions ahead of that conversation can be helpful.

Understanding your biopsy results

Unlike blood or urine tests, brain biopsy results do not fall into a "normal" or "abnormal" range. Instead, the tissue is examined by a pathologist, who looks at the cells under a microscope and may perform other testing to help determine a diagnosis. Results may show a tumor, infection, inflammation or another condition, or they may help rule out certain conditions that could be causing your symptoms.

Factors that can affect results

In some situations, a biopsy may not provide a clear diagnosis. This can happen if the tissue sample is very small or if the tissue shows a mix of changes that make it hard to identify one clear cause. If results are not clear, the care team may recommend more tests or another biopsy.

Imaging results, past treatments and where the lesion is located can all the overall understanding of biopsy results. Because of this, biopsy findings are reviewed together with imaging and other clinical information, rather than on their own.

What happens next

The next steps depend on what the biopsy shows. In some cases, the results lead directly to a treatment plan, such as surgery, medicine, or other therapies including radiation or chemotherapy. In other situations, careful monitoring or more tests may be recommended before deciding on treatment.

Your care team can explain the options, answer questions and help you understand the reasons behind each recommendation. Writing down questions or bringing a family member to these discussions can be helpful.

What to expect long term

Your long-term care plan depends on the diagnosis, and it can look different for each person. Some conditions need ongoing treatment, while others may only need monitoring with scans and follow-up visits. Staying in touch with your care team and letting team members know about any new or changing symptoms can help guide the next steps in your care.