Patent ID: 7377910

Claim:
A reagent injection device comprising: a flexible main tube, which is insertable into a body, said main tube comprising first, second, and third lumens provided therein, said third lumen being disposed closer to an axial center of the main tube than are the first and second lumens; a first guide wire that is insertable into the main tube through the first lumen and which is configured to guide the first guide wire to move back and forth by extending out of the main tube at a first position in an axial direction of the main tube; a second guide wire that is insertable into the main tube through the second lumen which is configured to guide the second guide wire to move back and forth by extending out of the main tube at a second position in a direction away from the first guide wire, wherein the first guide wire and the second guide wire are extendable from the main tube on a common plane with reference to the extended first guide wire and the extended second guide wire, said common plane being formed by the extended first guide wire and the extended second guide wire and extending through the extended first guide wire, the extended second guide wire, and the main tube; and a needle tube that is insertable into the main tube through the third lumen and which is configured to guide the needle tube to move back and forth by projecting from the main tube at a third position in a direction substantially or nearly orthogonal to the common plane and away from the common plane by using the first and second guide wires on the common plane as a support structure, said third position being disposed between the first position and the second position in the axial direction of the main tube, wherein the main tube further comprises an expandable and/or shrinkable balloon attached to its exterior, and a fourth lumen that supplies fluid for expanding the balloon is further provided inside of the main tube such that the center of the projection hole is positioned in the same plane that includes the center axis of the fourth lumen and the center axis of the main tube.