Patent ID: 6835193
Filing Date: 2004-12-28
Classification: A61B,A61M

Abstract:
A method for injecting a therapeutic fluid a controlled distance into the surface of an interior body cavity in a subject in need thereof, said method comprising:(a) introducing a catheter into the interior of a body cavity by advancing the catheter through the vascular system of the subject, said catheter comprising: i) an elongate hollow catheter body having a proximal end and a distal end with a flexible portion at the distal end thereof, said catheter body being sized and constructed to be advanced intravascularly into an interior body cavity of a subject; ii) 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, iii) 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, and iv) 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 advance the needle to the advanced needle position, thereby exposing a fixed length of the sharp tip of the needle; (b) contacting the surface of the body cavity with the distal end face of the catheter body, (c) advancing the sharp distal portion of the hollow needle the controlled distance into the surface of the body cavity; and (d) introducing a therapeutic amount of a therapeutic fluid into the surface of the body cavity through the sharp tip of the hollow needle.