INJECTION NEEDLE INSERTION BARRIER

摘要

A catheter system includes a positioning catheter for receiving an injection needle into its lumen. Structurally, the injection needle incorporates a plurality of loops that are mounted directly onto its shaft. As the injection needle is moved in a distal direction to exit from the lumen of the catheter, the loops are individually biased to transition from a folded configuration, and into a deployed configuration. In their deployed configurations, the loops create a barrier that is oriented perpendicular to the needle. Thus, the barrier acts to limit the depth of insertion of the needle into target tissue of a patient, to a predetermined depth, and to prevent perforation of the target tissue by the catheter tip.

主权项

1. A catheter system for performing an injection of fluid medicament into a tissue of a patient which comprises:
a catheter having a proximal end and a distal end, and formed with a lumen extending therebetween; an injection needle positioned on the catheter for reciprocating movement through the lumen of the catheter, wherein the injection needle has a proximal end and a distal end and defines an axis; a plurality of loops wherein each loop is an elongated wire having a first end and a second end and a midpoint therebetween to define a loop plane, wherein each end of the loop is affixed to the needle at respective points in a plane perpendicular to the axis of the needle, and wherein the loop is biased to transition in the loop plane between a folded configuration and a deployed configuration, and wherein during a configuration transition of the loop in the loop plane, the loop plane is rotated through a deployment angle β about an axis perpendicular to the axis of the needle, and further wherein each loop is affixed to the needle to avoid overlap and interference with another loop during the configuration transition; and a means for collectively moving the plurality of loops during their respective configuration transition to create a barrier wherein the midpoints of each loop are located at a distance “d” proximal the distal end of the injection needle to prevent an insertion of the needle any deeper than the distance “d” into the tissue of the patient.