Patent ID: 6796963
Filing Date: 2004-09-28
Classification: A61B,A61M

Abstract:
A flexible tissue injection catheter with controlled depth penetration, said catheter comprising:a) an elongate hollow catheter body having a proximal end and a distal end with a flexible portion at a distal tip thereof, said catheter body being sized and constructed to be advanced intravascularly into an interior body cavity of a subject; b) a hollow needle housed throughout the catheter body, said needle having a distal portion with a sharp tip and a proximal portion in fluid communication with a fluid source, said needle further having a retracted needle position wherein the sharp tip of the needle is disposed within the catheter body, and an advanced needle position wherein the sharp tip of the needle extends a fixed distance beyond a distal end face of the catheter body, c) a needle stop attached to the needle that tethers the distal portion of the needle during flexure while the proximal portion of the needle remains freely slideable within the catheter body, d) a distance compensator portion of the proximal portion of the needle that extends from the proximal end of the catheter body when the catheter body is not deflected and moves at least partially within the catheter body when the flexible portion is deflected, and e) an advancement mechanism attached to the needle for advancing the needle distally a fixed distance to the advanced needle position, wherein the needle stop prevents withdrawal of the distal portion of the needle into the catheter body upon flexure of the catheter prior to actuation of the advancement mechanism to move the needleâ€”to the advanced needle position, thereby exposing a fixed length of the sharp tip of the needle.