Directional probe for radio-guided surgery: A pilot study

Area of Science:

• Medical Imaging
• Surgical Technology
• Nuclear Medicine

Background:

• Sentinel lymph node (SLN) biopsy techniques have advanced significantly.
• Intraoperative use of Gamma Probes (GPs) for SLN mapping is increasingly common.
• Existing GPs lack directional information, potentially prolonging surgery.

Purpose of the Study:

• To evaluate a novel directional Gamma Probe (GP) prototype.
• To assess a proof-of-concept prototype designed to identify radiopharmaceutical uptake direction.
• To develop a tool for reducing surgery time by effectively guiding surgeons.

Main Methods:

• A prototype with three coupled CsI(Tl) scintillation crystals and silicon photomultipliers was developed.
• The system utilizes a central detector for precise localization and two lateral sensors for a broader view.
• Isosensitivity curves and quality criteria (sensitivity, spatial resolution) were measured for prototype assessment.

Main Results:

• The central detector demonstrated high sensitivity (>5 cps/kBq) and good spatial resolution (7.2 mm FWHM).
• Lateral detectors provided widespread isosensitivity distributions, indicating a larger field of view.
• The system met minimal requirements for GP systems, showing satisfactory performance and reliability.

Conclusions:

• The directional GP prototype enables rapid localization and precise guidance using its combined detectors.
• Unlike conventional GPs, this device can simultaneously identify multiple radiopharmaceutical uptake areas.
• Preliminary results support further development for intraoperative validation.