Puncture needle and method of using guide wire

A method of using a guide wire, comprising:

• forming a through hole by puncturing a needle tube from the inside of a first lumen through a wall of the first lumen and a wall of a second lumen and arranging a needle tip of the needle tube inside the second lumen;
• moving a protective tube housed inside the needle tube forward along a longitudinal axis until a protrusion provided on at least part of an outer peripheral surface of the protective tube abuts a step portion provided inside the needle tube and thereby make a tip portion of the protective tube protrude from the needle tip of the needle tube;
• maintaining the protrusion in a state of pressing against the step portion from the proximal end side by moving forward the tube slider connected to the proximal end of the protective tube relative to the needle slider connected to the proximal end of the needle tube in a state where the protrusion has abutted the step portion,
• making a guide wire, which extends through the inside of the protective tube, protrude from a distal end of the protective tube into the inside of the second lumen;
• and
• positioning the guide wire from the first lumen to the second lumen by removing the needle tube and the protective tube from the through hole.

A puncture needle comprising:

• a tubular sheath having a longitudinal axis;
• a needle tube that is arranged inside the sheath so as to be movable along the longitudinal axis and that has a needle tip at a distal end thereof;
• and
• a protective tube that is arranged inside the needle tube so as to be movable along the longitudinal axis and that has a lumen into which a guide wire is inserted so as to be movable along a direction of the longitudinal axis;
• wherein the needle tube includes a needle tip portion that includes the needle tip of the needle tube, a needle base portion that includes a proximal end of the needle tube, and a connection tube that allows the needle tip portion to be fitted inside thereof on a distal end side thereof and allows the needle base portion to be fitted inside thereof on a proximal end side thereof, and a step portion formed by the connection tube and a proximal end surface of the needle tip portion fitted into the connection tube such that an inner diameter decreases by one step in the step portion toward the distal end of the needle tube, and
• wherein the protective tube has a protrusion, which protrudes radially outward, on at least part of an outer peripheral surface thereof at a position which is nearer a proximal end side of the protective tube than the step portion is, and
• a distal end of the protective tube is positioned at a position so as to protrude from the distal end of the needle tube when the protrusion abuts the step portion from the proximal end side of the protective tube.