Catheter with retractable anchor mechanism

An elongated catheter having a distal end and a proximal end, the distal end of which is adapted to be inserted into a human body, the catheter comprising:

• a flexible tubular outer member substantially concentric to a longitudinal axis of the catheter, said outer member extending substantially the entire length of the catheter;
• a flexible tubular inner member lying within said outer member, said inner member having a distal end located near the distal end of the catheter, said inner member extending substantially to the proximal end of the catheter and defining a central lumen,
• retractable anchor means located near the distal end of the catheter for stabilizing the position of the catheter within the body, said anchor means comprising a portion of said flexible tubular outer member and being moveable from a first extended position to a second retracted position,
• at least one port in the outer member between the central lumen and an exterior of the catheter, said at least one port being located between the distal end of the catheter and said retractable anchor means, such that drugs or therapeutic agents may be introduced into the body or body fluids may be withdrawn from the body through said at least one port,
• a stylet for insertion in the central lumen of the catheter, said stylet having an enlarged tip of predetermined shape at a distal end, thereof and
• capture means connected to said anchor means for releasably receiving the enlarged tip of said stylet, the movement of said capture means being limited in a proximal direction by the distal end of said inner member which acts as a stop, such that said anchor means is moved from the first extended position to the second retracted position by inserting said stylet and applying pressure in a distal direction and is moved from the second retracted position to the first extended position by applying pressure in the proximal direction until said capture means contacts the distal end of said inner member at which point continued pressure in the proximal direction results in release of the enlarged tip of said stylet from said capture means.

An epidural lead having a distal end and a proximal end, the distal end of which is adapted to be inserted into a human body, the epidural lead comprising:

• a flexible tubular outer member substantially concentric to a longitudinal axis of the lead, said outer member extending substantially the entire length of the lead,
• a flexible tubular inner member lying within said outer member, said inner member having a distal end located near the distal end of the lead, said inner member extending substantially to the proximal end of the lead and defining a central lumen,
• at least one electrode secured to said outer member near the distal end of the lead,
• at least one conductor connected to said at least one electrode for transmitting electrical signals from the proximal end of the lead to said a least one electrode,
• retractable anchor means located near the distal end of the lead for stabilizing the position of the lead within the body, said anchor means comprising a portion of said flexible tubular outer member and being moveable from a first extended position to a second retracted position,
• a stylet for insertion in the central lumen of the lead, said stylet having an enlarged tip at a distal end, thereof and
• capture means connected to said anchor means for releasably receiving the enlarged tip of said stylet, the movement of said capture means being limited in a proximal direction by the distal end of said inner member which acts as a stop, such that said anchor means is moved from the first extended position to the second retracted position by inserting aid stylet and applying pressure in the proximal direction until said capture means contacts the distal end of said inner member at which point continued pressure in the proximal direction results in release of the enlarged tip of said stylet from said capture means.

An elongated catheter having a distal end and a proximal end, the distal end of which is adapted to be inserted into a human body, the catheter comprising:

• a flexible tubular outer member substantially concentric to a longitudinal axis of the catheter, said outer member extending substantially the entire length of the catheter,
• a flexible tubular inner member lying within said outer member, said inner member having a distal end located near the distal end of the catheter, said inner member extending substantially to the proximal end of the catheter and defining a central lumen,
• retractable anchor means located near the distal end of the catheter for stabilizing the position of the catheter within the body, said anchor means being movable from a first extending position to a second retracted position, said retractable anchor means comprising a formed portion of said outer member, sad formed portion having an outer dimension substantially identical to an outer dimension of the remainder of the outer member when in the second retracted position and having an outer dimension greater than the outer dimension of the remainder of the outer member when in the first extended position,
• at least one port int eh outer member between the central lumen and an exterior of the catheter, said at least one port being located between the distal end of the catheter and said retractable anchor means, such that drugs or therapeutic agents may be introduced into the body or body fluids may be withdrawn from the body through said at least one port,
• a stylet for insertion in the central lumen of the catheter, said stylet having an enlarged tip of predetermined shape at a distal end, thereof and
• capture means connected to said anchor means for releasably receiving the enlarged tip of said stylet, the movement of said capture means being limited in a proximal direction by the distal end of said inner member which acts as a stop, such that said anchor means is moved from the first extended position to the second retracted position by inserting said stylet and applying pressure in a distal direction and is moved from the second retracted position to the first extended position by applying pressure in the proximal direction until said capture means contacts the distal end of said inner member at which point continued pressure in the proximal direction results in release of the enlarged tip of said stylet from said capture means.

An epidural lead having a distal end and a proximal end, the distal end of which is adapted to be inserted into a human body, the epidural lead comprising:

• a flexible tubular outer member substantially concentric to a longitudinal axis of the lead, said outer member extending substantially the entire length of the lead,
• a flexible tubular inner member lying within said outer member, said inner member having a distal end located near the distal end of the lead, said inner member extending substantially to the proximal end of the lead and defining a central lumen,
• at least one electrode secured to said outer member near the distal end of the lead,
• at least one conductor connected to said at least on electrode for transmitting electrical signals from the proximal end of the lead to said a least one electrode,
• retractable anchor means located near the distal end of the lead for stabilizing the position of the lead within the body, said anchor means being moveable from a first extended position to a second retracted position, said retractable anchor mans comprising a plurality of longitudinal slits formed in said outer member, said slits defining a plurality of lobes which are compressed and extend outwardly away from the longitudinal axis of the lead when in the first extended position and which lie substantially parallel to the longitudinal axis access of the lead when in the second retracted position,
• a stylet for insertion in the central lumen of the lead, said stylet having an enlarged tip at a distal end thereof, and
• capture means connected to said anchor means for releasably receiving the enlarged tip of said stylet, the movement of said capture means being limited in a proximal direction by the distal end of said inner member which acts as a stop, such that said anchor means is moved from the first extended position to the second retracted position by inserting said stylet and applying pressure in the proximal direction until said capture means contacts the distal end of said inner member at which point continued pressure in the proximal direction results in release of the enlarged tip of said stylet from said capture means.