A Side-viewing Fluorescence Needle Probe for Brain Biopsy Guidance.

Area of Science:

• Biomedical Optics
• Surgical Technology
• Cancer Diagnostics

Background:

• Accurate detection of malignant brain tissue during surgery is crucial for complete tumor resection and improved patient outcomes.
• Current methods for intraoperative tissue identification can be time-consuming or lack sufficient sensitivity.
• Optical techniques offer potential for real-time, sensitive tissue characterization.

Purpose of the Study:

• To develop and evaluate a fiber-optic needle probe for the detection of malignant brain tissue.
• To assess the probe's sensitivity and feasibility in mimicking brain tissue and in fresh human brain samples.

Main Methods:

• A dual-fiber optic probe was designed with separate excitation and detection channels, featuring a high numerical aperture collection fiber.
• The probe was integrated into a 16-gauge needle, utilizing angle-polished and silver-coated fibers for side-facing fluorescence detection.
• Sensitivity was tested using a fluorescent brain phantom and validated on fresh human glioblastoma tissue.

Main Results:

• The probe demonstrated sensitivity comparable to a surgical microscope, detecting fluorescence through non-fluorescent obscuring layers.
• Detection was successful through 0.4 mm of low-absorption and 0.3 mm of high-absorption non-fluorescent material.
• The probe identified characteristic protoporphyrin IX fluorescence in malignant brain tissue, with signal strength correlating to tumor cell density.

Conclusions:

• The developed dual-fiber fluorescence needle probe is feasible for identifying malignant brain tissue during surgery.
• This technology advances the application of optical methods for real-time surgical guidance and improved cancer resection.