What it is
Stereotactic brain biopsy uses preoperative imaging — MRI, CT, or PET — to plan a precise trajectory to a brain target, then guides a biopsy needle along that trajectory through a small burr hole. Tissue is obtained with minimal disruption to the surrounding brain, sent for pathological analysis, and the result informs treatment planning.
The procedure can be performed with a rigid frame fixed to the skull (frame-based stereotaxy) or using frameless image-guided navigation based on preoperative MRI. Both are accurate; the choice depends on lesion characteristics and institutional preference.
When a biopsy is the right approach
Not every brain lesion needs to be resected. Biopsy is appropriate when:
- The lesion is in a location where open surgery would carry significant neurological risk
- The imaging appearance is not characteristic enough to treat without tissue confirmation
- The likely diagnosis (CNS lymphoma, infection, inflammatory/demyelinating disease) would be better managed without surgery or responds specifically to non-surgical treatment
- Multiple lesions make full surgical treatment impractical and pathology from one lesion will guide treatment of all
Obtaining the right tissue diagnosis before committing to chemotherapy, radiation, or immunosuppression is not a delay — it is good medicine.
What to expect
Stereotactic biopsy is typically performed under general anesthesia (or conscious sedation for select frame-based cases) and usually requires one night of observation. The main risk is hemorrhage along the biopsy tract, which occurs in a small percentage of cases; most are minor. The diagnostic yield with modern stereotactic targeting is high, and non-diagnostic biopsies are uncommon at experienced centers.