Brain biopsy: Biopsy of the brain. Removal of a small piece of tissue from the brain for diagnostic purposes.

One way the procedure may be done is by stereotactic needle biopsy in which the spot to be biopsied is located three-dimensionally, the information is entered into a computer, and the computer calculates the information and positions a needle to remove the biopsy sample.

A brain biosy may be done in search of evidence for or against a brain tumor, Alzheimer disease, an inflammatory process in the brain, and so. A brain biopsy can be a invaluable source of diagnostic information but it is not without risks.