What is a brain biopsy?

A brain biopsy is used to diagnose illness. In the procedure, a tumor or a piece of tissue is removed from the brain for examination under a microscope. Types of brain biopsies include:

  • needle biopsy
  • stereotactic biopsy
  • open biopsy

In a needle biopsy, a small hole is drilled into the skull and a narrow, hollow needle is placed into the incision to extract a tiny portion of the tumor or tissue.

A stereotactic biopsy uses 3-D imaging technology, as well as data from CT and MRI scans, to examine a tumor or a piece of the brain. Stereotactic biopsy is a minimally invasive procedure.

Open biopsies are the most common form of brain biopsy and the most invasive. During the procedure, your surgeon will remove a piece of bone from your skull while you’re under general anesthesia. This allows the tumor to be exposed and removed. This is riskier than other brain biopsy methods and the recovery time is longer.

A brain biopsy can help doctors diagnose brain illnesses, allowing them to devise treatment plans. Doctors usually order brain biopsies to determine whether a tumor is cancerous or benign. It can also be ordered to confirm the diagnosis of Creutzfeldt-Jakob disease, a dementia-related disease. Inflammatory disorders and infections can also be identified through brain biopsy.

A brain biopsy is seen as a last resort for diagnosing an illness and is performed after imaging techniques prove inconclusive. In the case of dementia, the role of brain biopsy is sometime used for diagnosis, but the practice still remains uncertain. Research shows that the procedure may become more worthwhile for diagnosing dementia as new therapies are discovered. But for now, diseases such as Alzheimer’s are usually diagnosed clinically and through imaging tests.

Brain surgery is always risky, but needle and stereotactic biopsies are less invasive than open biopsies. They also have fewer complications.

Going under anesthesia always poses risks for older adults and people with dementia. All types of brain biopsies can result in swelling or bleeding in the brain. They can also lead to:

  • infection
  • seizure
  • stroke
  • coma

Sometimes, tests on the sampled tissue are inconclusive and the procedure must be repeated. Risks have been reduced with modern technology such as stereotactic equipment.

Lab work and a CT scan or an MRI may be ordered, before your surgery. Your doctor may ask you to discontinue using blood thinners and aspirin. You may need to wash your hair with a special shampoo the night before surgery.

Brain biopsies are performed in hospital operating rooms. Your surgeon may place a head ring on you, which is held in place with pins. In some cases, a CT scan or an MRI is taken in conjunction with the biopsy, often with the head ring in place. In other cases, the CT scan or MRI is taken before the biopsy and the results are uploaded into surgical equipment. This eliminates the need for a head ring.

In needle or stereotactic biopsies, a small incision, a few millimeters long, is made. After a tiny hole is drilled into the skull, a small needle is placed into the brain and the biopsy is obtained. If the biopsy is remotely controlled, your doctor can navigate the needle during surgery by watching a monitor.

After surgery, the incision is stapled or sutured. In the case of open biopsies, the bone flap is replaced with plates or wires. If there is swelling or infection, the flap won’t be replaced. This is called a craniectomy.

Your doctor will go over the results of the biopsy with you and come up with a treatment plan if needed. In some cases, particularly with stereotactic and needle biopsies, you may go home on the same day. Although a one-day hospital stay is usually required. The hospital stay may be longer depending on your health and whether any complications arise during surgery.