Noncontact monitoring of incision depth in laser surgery with air-coupled ultrasound transducers

Lack of haptic feedback during laser surgery makes it difficult to control the incision depth, leading to high risk of undesired tissue damage. Here, we present a new feedback sensing method that accomplishes noncontact real-time monitoring of laser ablation procedures by detecting shock waves emanating from the ablation spot with air-coupled transducers. Experiments in soft and hard tissue samples attained high reproducibility in real-time depth estimation of the laser-induced cuts. The advantages derived from the noncontact nature of the suggested monitoring approach are expected to advance the general applicability of laser-based surgeries.