| abstract |
A catheter assembly (10), includes a flexible inner catheter tube (11) which is telescopically translatable through a shorter, outer sheath tube (12). The inner catheter tube (11) has an injection needle (19) projection from its distal end (13) which is retracted into the open distal end (14) of the sheath tube (12) as the sheath tube traverses the endoscope or other tubular passage. Upon reaching the desired location, the needle (19) and the distal end (13) of the inner catheter tube (11) are projected from the distal end (14) of the sheath (12) by applying an axial force to the catheter tube at a location beyond the proximal end (17) of the sheath (12). A positional locking mechanism includes an elastomeric washer (30) which concentrically slidably engages the catheter tube (11) at a location beyond the proximal end (17) of the sheath (12). The washer (30) is selectively axially compressed between two locking members (25, 21) which are disposed about the sheath (12) and catheter tube (11), respectively. The washer (30) is radially constricted so that the axial compression produces a radial compression which results in a gripping action on the catheter tube (11). |