Automatic Focusing and Robotic Scanning Mechanism for Precision Laser Ablation in Neurosurgery

We have developed an laser ablation system with an automatic focusing (AF) and robotic scanning mechanism for precision malignant gliomas resection in neurosurgery. A 5-aminolevulinic acid (5-ALA)-induced fluorescence based intra-operative tumor diagnosis technique has been incorporated into the robotic laser ablation system. The system enables an intra-operative identification of the position of a tumor with fluorescence illuminated by a laser excitation. The AF and robotic scanning mechanism assists in tracking the surface of the malignant brain tumors, and provides position information for both laser scanning in 5-ALA fluorescence identification and laser ablation in tumor resection. Experimental results showed the automatic focus device had a precision of 0.5 mm and the mechanism could track the brain surface with a movement caused by pulsation and respiration.