Miniaturized mechanical design of a spiral-scanning laser ablation instrument for advanced surgical applications

Recent developments in picosecond pulsed laser ablation show considerable promise for the minimally invasive removal of neoplastic tissue. This technology is particularly noteworthy for its selective targeting of diseased tissue while substantially reducing collateral damage to adjacent healthy areas. Such precision is critical for interventions in delicate and anatomically complex regions. However, integrating this advanced technique into constrained or intricate anatomical spaces presents a significant practical barrier. Overcoming these limitations is essential for the technology to achieve its full clinical potential and broader adoption. Building upon our earlier spiral-scanning laser ablation prototype, we have engineered a substantially enhanced probe. This next-generation probe features a smaller footprint and improved scanning capabilities. Our newly developed probe has a compact 12 mm outer diameter and 300 mm in length, making it well-suited for endoscopic and laparoscopic procedures. A key innovation is its distal scanning tip, designed to generate Archimedean spiral trajectories. This ensures an even distribution of laser energy across the target area. The system achieves a laser spot diameter of 20 microns and can completely scan a 0.6 mm radius area in approximately one and a half minutes by following a spiral trajectory at a speed of 2 mm per second. The development process required solving several key engineering challenges, including mechanical miniaturization, enabling perpendicular laser emission from the probe surface during scanning, and maintaining fiber tip stability throughout rapid spiral movements. Addressing these challenges has significantly enhanced the probe’s effectiveness and reliability for potential use in clinical scenarios. Conducted experimental results have confirmed the superior performance of our new probe, demonstrating consistent, tightly packed spiral patterns that achieve nearly complete target coverage with minimal unscanned regions. Furthermore, real-time imaging during experimental setups confirmed that the laser spot maintains a constant speed of 2 mm/s along the Archimedean spiral during scanning. Preliminary results underscore significant advancements in scanning sensitivity, speed, and coverage compared to the initial prototype, affirming the device’s strong potential for diverse clinical applications.