Laser-based pulsed liquid microjet for surgery

Abstract

A water microjet device that can be used for precise dissection of soft tissue in surgical procedures has been developed. The water jet is generated by irradiating a pulsed Ho : YAG laser, through an optical fiber, into a thin tube/catheter filled with water or a physiological saline solution. Pulsed laser irradiation within the tube evaporates the water generating a vapor bubble, whose rapid expansion drives a microjet of water out of the tube through a micronozzle of 100 ~ 200 mm exit diameter. This laser-induced microjet can readily penetrate a soft tissue in human body. The jet is applicable to neuroendoscopic surgery, treatment of cerebral thrombosis, intravascular drug delivery, etc. The thermal effects and the controllability of the jet were first investigated on a 10% gelatin layer that simulates a soft tissue, and then the jet was used to dissect the ventricular wall of a cadaver rabbit.
The experimental results indicated a well-controlled incision, preserving capillary blood vessels thicker than 0.2 mm in diameter, and the collateral damage to the tissue was negligible.