| 摘要 |
Catheter 66 for delivering a medical agent to tissue external to a body passage through which the catheter 66 is inserted. Catheter 66 includes a tissue piercing member 30, e.g., a needle 30 having an asymetrically flexible rectangular cross-section, such that the member 30 is substantially more flexible about a first cross-sectional axis than about a second cross-sectional axis. The tissue piercing member 30 is readily deflected about one axis, away from the catheter 66 and into the tissue, while minimizing buckling of the tissue piercing member 30 about the other axis. The catheter 66 can include a balloon 20located proximal to and on the same side as the piercing member 30, and a second balloon 120 located distal to and on the opposite side as the piercing member 30. When inflated, the balloons 20, 120 cause the portion of the catheter 66 between the balloons 20, 120 to flex and bend, facilitating penetration of the tissue by the tissue piercing member 30. |
