Ultrasonic surgical knife

Surgical instrument having a forward portion, a rearward portion, and comprising ultrasonic generator means adapted to subject a sonotrode, disposed at a forward end of said surgical instrument, to an ultrasonic vibratory movement, the surgical instrument being traversed by at least one axial suction channel connecting the forward portion to the rearward portion, means for guiding laser radiation to a forward end of the sonotrode, focusing means for directing said laser radiation through the axial suction channel, and for focusing said laser radiation at a focal point located in front of the forward end of the sonotrode, and a secondary suction channel opening in the axial suction channel, adjacent said focusing means and creating a suction flow (F), and means for supplying a gaseous flow in the axial suction channel, which opens into said axial suction channel intermediate the secondary suction channel and the focusing means, and which creates a gas flow (F') opposite the flow of suction.