Optical Brain Biopsy with a Fluorescence and Vessel Tracing Probe

Area of Science:

• Neurosurgery
• Oncology
• Medical Imaging

Background:

• Accurate stereotactic biopsies are crucial for brain tumor diagnosis and treatment.
• Repetitive needle insertions increase risks of brain lesioning, hemorrhage, and prolonged procedures.

Purpose of the Study:

• To evaluate the clinical benefits of a combined 5-aminolaevulinic acid (5-ALA) fluorescence and laser Doppler flowmetry system.
• To enhance the detection of malignant brain tumors and blood vessels during stereotactic biopsies.

Main Methods:

• Optical measurements (fluorescence spectra, microvascular blood flow, tissue grayness) were recorded along planned trajectories in 20 patients.
• Biopsies were taken at preplanned positions, with diagnoses compared to fluorescence signals.
• The system used the Leksell Stereotactic System and a manual insertion device.

Main Results:

• Fluorescence signals indicated malignant tissue in 23 of 28 trajectories, with deviations from the target in 4 cases.
• Increased microcirculation, a risk factor for hemorrhage, was detected in 40 of 905 measured positions.
• Procedure time per trajectory ranged from 5 to 10 minutes.

Conclusions:

• The combined system provides real-time feedback on blood flow and malignant tissue presence near the target.
• This method enhances the precision and safety of stereotactic biopsy procedures.
• The system has the potential to reduce overall procedure time.