Electrode irrigation using micro-jets

A medical apparatus, comprising:

• an elongate probe, for insertion into a body of a subject, the probe comprising:
• an insertion tube, having a distal end for engagement with a target tissue in the body;
• a distal tip, which is fixed to the distal end of the insertion tube and is coupled to apply energy to the tissue inside the body, and which has an outer surface with a plurality of perforations formed therethrough, the perforations being distributed circumferentially and longitudinally over the distal tip and having diameters between 10 μm and 25 μm;
• a lumen passing through the insertion tube and coupled to deliver a fluid to the tissue via the perforations;
• an energy generator, for coupling to the probe so as to supply the energy to the distal tip;
• and
• an irrigation pump, for coupling to the lumen so as to supply the fluid via the lumen and the perforations to the tissue.

A method for treatment, comprising:

• inserting an elongate probe into a body of a subject, the elongate probe comprising:
• an insertion tube, having a distal end for insertion into the body;
• a distal tip, which is fixed to the distal end of the insertion tube and is coupled to apply energy to a tissue inside the body, and which has an outer surface with a plurality of perforations formed therethrough, the perforations being distributed circumferentially and longitudinally over the distal tip and having diameters between 10 μm and 0.25 μm;
• a lumen passing through the insertion tube and in fluid communication with the perforations;
• applying energy through the distal tip to tissue inside the body;
• and
• supplying a fluid via the lumen and the perforations to the tissue.