| 摘要 |
A safety penetrating instrument comprises an elongate, tubular needle having a longitudinal axis, a proximal end and a distal end having a peripheral edge, the edge being disposed in a plane at an acute angle to the longitudinal axis of the needle, thereby defining a sharp tip for penetrating anatomical tissue; a safety probe movably disposed within the needle and having a proximal end and a distal end having an angled end surface, the safety probe being movable between an extended position, in which its distal end protrudes from the needle tip, and a retracted position, in which its angled end surface is substantially coplanar with the needle peripheral edge, thereby exposing the needle tip and providing a smooth tissue penetrating surface; a hub for receiving the proximal ends of the needle and the safety probe; bias means for biasing the safety probe toward its extended position and which, in response to a proximally directed force applied to the safety probe distal end, permits the safety probe distal end to move to its retracted position; an elongate, tubular portal sleeve surrounding the needle and having a distal end disposed adjacent the needle distal end and a proximal end; a housing which abutts the hub and to which the proximal end of the needle is secured. <IMAGE> |
