| 摘要 |
<p>A spinal needle system that signals entry into the epidural space tip stabilizes the dura mater. The system includes a cannula (17) having at a distal tip (52) an annular surface surrounding a terminal port and at least one barb (50) projecting at an angle from the annular surface of the cannula for grasping and controlling the tissue. Each barb (50) is formed having a sharp edge configured to grasp the tissue as the tubular member is rotated about its longitudinal axis. One implementation of the system includes a plurality of unidirectional barbs (50) spaced around the annular surface of the cannula (17). The system includes an indicator mechanism that gives a visual and a tactile indication of when the cannula encounters and penetrates tissue. The system facilitates the appropriate placement of an epidural or subdural catheter or patch of any kind.</p> |
