| 摘要 |
A valve (10) useful as a fluid flow check valve or as a self-sealing, penetrable, hemostatic valve for sealing a catheter introducer (12) includes a seal (26) which is highly resistant to tearing and leakage, yet is capable of accepting repeated penetrations by devices of a wide variety of diameters. The seal (26) is disk-shaped and is composed of a thermoplastic styrenic elastomer, such as a styrene-ethylene/butylene-styrene block copolymer, of very low durometer (a hardness of no more than about 30 Shore A). The seal (26) is preferably contained in a valve body (40) and is disposed between a valve seat (48) in the valve body (40) and a cap (56) connected to the valve body (40) and becomes deflected upon assembly of the valve. The seal (26) includes at least one perforation (34) closed by such deflection. This deflection also provides the seal (26) with a proximal or upstream concave surface (30), and this deflection along with the clamping of the periphery of the seal by and between the cap and the valve seat, makes it highly resistant to inversion during repeated removals and manipulations of interventional devices passing through the valve (10). The valve (10) of the present invention is particularly advantageous in that it seals the introducer (12) with a high degree of effectiveness when no interventional device lies across its seal (26), and in that it offers a high resistance to tearing when penetrated by devices of large diameter.
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