Fine-needle aspiration biopsy of the central nervous system performed freehand under computed tomography guidance without stereotactic instrumentation.

Background: Biopsy of the central nervous system (CNS) has been reported previously using relatively large-caliber (12-17-gauge) biopsy instruments with or without stereotactic guidance. In this series, fine-needle aspiration biopsies (FNABs) were performed using a smaller diameter needle to evaluate mass lesions of the CNS.

Methods: One hundred thirty FNABs were performed freehand under computed tomography (CT) guidance without stereotactic instrumentation guidance using a 22-gauge needle.