High-speed ultrafast laser surgery scalpel: design, validation, and evaluation

Ultrafast laser ablation offers unparalleled spatial and thermal confinement, making it a compelling candidate for high-precision spinal bone surgery. However, the inherently low ablation rates of ultrafast lasers and the challenges associated with probe miniaturization have significantly impeded their clinical translation. In this work, we present the design and prototyping of a new-generation, fiber-delivered ultrafast laser surgical scalpel optimized for both minimally invasive and open spinal procedures. The system integrates high-efficiency laser delivery via a Kagome hollow-core photonic crystal fiber, a piezoelectric fiber-scanning mechanism for compact beam steering, a high-demagnification miniaturized objective for enhanced ablation efficiency, and an opto-mechanical architecture enabling controlled depth-wise material removal and handheld operation. Prior efforts in parametric optimization informed the selection of pulse duration, spot size, and field-of-view to enable ablation rates exceeding 20 mm3/min under high-average-power operation. The optical design achieves a focused spot radius of 7.87 μm with a working distance of 3.8 mm, suitable for deep spinal bone incisions. Preliminary handheld tests on bone and synthetic spine models demonstrate stable focal-plane ablation, ergonomic maneuverability, and access to confined anatomical regions. These results establish a scalable and clinically translatable platform for ultrafast laser–based spinal surgery and represent a significant step toward replacing conventional mechanical bone removal tools.