One-Insertion Stereotactic Brain Biopsy Using In Vivo Optical Guidance—A Case Study

Abstract

BACKGROUND: Stereotactic neurosurgical brain biopsies are afflicted with risks of inconclusive results and hemorrhage. Such complications can necessitate repeated trajectories and prolong surgical time. OBJECTIVE: To develop and introduce a 1-insertion stereotactic biopsy kit with direct intraoperative optical feedback and to evaluate its applicability in 3 clinical cases. METHODS: An in-house forward-looking probe with optical fibers was designed to fit the outer cannula of a side-cutting biopsy kit. A small aperture was made at the tip of the outer cannula and the edges aligned with the optical probe inside. Stereotactic biopsies were performed using the Leksell Stereotactic System. Optical signals were measured in millimeter steps along the preplanned trajectory during the insertion. At the region with the highest 5-aminolevulinic acid (5-ALA)–induced fluorescence, the probe was replaced by the inner cannula, and tissue samples were taken. The waiting time for pathology diagnosis was noted. RESULTS: Measurements took 5 to 10 minutes, and the surgeon received direct visual feedback of intraoperative 5-ALA fluorescence, microcirculation, and tissue gray-whiteness. The 5-ALA fluorescence corroborated with the pathological findings which had waiting times of 45, 50, and 75 minutes. Because only 1 trajectory was required and the patient could be prepared for the end of surgery immediately after sampling, this shortened the total surgical time. CONCLUSION: A 1-insertion stereotactic biopsy procedure with real-time optical guidance has been presented and successfully evaluated in 3 clinical cases. The method can be modified for frameless navigation and thus has great potential to improve safety and diagnostic yield for both frameless and frame-based neurosurgical biopsy procedures.

Combined Use of Frameless Neuronavigation and In Situ Optical Guidance in Brain Tumor Needle Biopsies

“…So far, the probe system introduced in this study has been adapted for the StealthStation and 5-ALA, but it can be modified to fit other setups. Modifying the probe dimensions allows for integration with the LSS frame [19] and use during tumor resection [50].…”

“…Furthermore, the system monitors changes in microcirculation and tissue gray-whiteness by using laser Doppler flowmetry (LDF) [16,17]. This setup was optimized for frame-based biopsy with the Leksell Stereotactic System (LSS) in a 20-patient cohort [18] and further integrated with an LSS-compatible biopsy needle [19].…”