gms | German Medical Science

Objective: The gold standard for stereotactic brain biopsy target localization has been frame-based stereotaxy. Recently, frameless stereotactic techniques have become increasingly utilized. The authors report the clinical results for 15 frameless biopsies and describe technical tips considering when procedure.

Method: The authors retrospectively analyzed 15 patients undergoing frameless stereotactic biopsy at Gachon Gil Medical Center from 2013 to 2015. Variable factors including tumor location, volume, biopsy site, and entry point were analyzed. The operative details of biopsy procedure, diagnostic yield, and complications are reported.

Results: The diagnostic yield was 93% (14 of total 15 cases). The mean tumor volume was 15.07?. The most common biopsy site was basal ganglia/thalamus (5 cases) and entry point was Kocher point (6 cases). Histopathology was common in the following order: Primary central nervous system lymphoma (4 cases), glioblastoma multiforme (2 cases), and anaplastic astrocytoma (2 cases). Postoperative complications occurred in 3 cases: minimal bleeding at biopsy site (1 case) and minimal bleeding along the biopsy trajectory (2 cases). No patient required operation for hematoma evacuation.

Conclusions: Comparing with the clinical results of the frame-based brain biopsy which several studied has reported, the frameless stereotactic brain biopsy was no significant differences in the diagnostic yield and complications. However, the authors found that the trajectory angle of the biopsy needle was limited within 10 degrees because of structures to fix in the skull bone. This limitation should be considered when making an operative plan and it needs to improve such disadvantage.