Abstract: A prosthetic implantable device that offers a reduction in fluid loss when the device is punctured, such as by a dialysis needle or suture needle, and the needle is subsequently removed. The device may be made to be thin and flexible, and with longitudinal stretch, in order that it also offers good handling and kink resistance to a surgeon. While the device is preferably of tubular form, flat sheets or other forms may also be made. The device includes inner and outer layers of a porous material having a microstructure of nodes interconnected by bent fibrils, and having void spaces between adjacent bent fibrils. The inner and outer layers are joined by an elastomeric adhesive that may interpenetrate the void spaces of the adjacent surfaces of the inner and outer layers, that is, the inner surface of the outer layer and the outer surface of the inner layer.

Abstract: A prosthetic implantable device that offers a reduction in fluid loss when the device is punctured, such as by a dialysis needle or suture needle, and the needle is subsequently removed. The device may be made to be thin and flexible, and with longitudinal stretch, in order that it also offers good handling and kink resistance to a surgeon. While the device is preferably of tubular form, flat sheets or other forms may also be made. The device includes inner and outer layers of a porous material having a microstructure of nodes interconnected by bent fibrils, and having void spaces between adjacent bent fibrils. The inner and outer layers are joined by an elastomeric adhesive that may interpenetrate the void spaces of the adjacent surfaces of the inner and outer layers, that is, the inner surface of the outer layer and the outer surface of the inner layer.

Abstract: A prosthetic implantable device that offers a reduction in fluid loss when the device is punctured, such as by a dialysis needle or suture needle, and the needle is subsequently removed. The device may be made to be thin and flexible, and with longitudinal stretch, in order that it also offers good handling and kink resistance to a surgeon. While the device is preferably of tubular form, flat sheets or other forms may also be made. The device includes inner and outer layers of a porous material having a microstructure of nodes interconnected by bent fibrils, and having void spaces between adjacent bent fibrils. The inner and outer layers are joined by an elastomeric adhesive that may interpenetrate the void spaces of the adjacent surfaces of the inner and outer layers, that is, the inner surface of the outer layer and the outer surface of the inner layer.

Abstract: A tube of porous PTFE having at least two first and at least two second regions wherein the at least two first regions have a greater density than the at least two second regions. For tubes of porous expanded PTFE having a microstructure of nodes interconnected by fibrils, the at least two first regions have a mean fibril length that is less than that of the at least two second regions. Preferably the regions are arranged in the form of ring-shaped segments of the tube wherein denser segments alternate along the length of the tube with less dense segments. Other arrangements between the different regions are possible; for example, the regions may be oriented in a spiral relationship with each other along the length of the tube. The porous PTFE tubes of the present invention have excellent radial compression resistance without requiring additional exterior reinforcing members due to the presence of the denser regions that are provided with a circumferential orientation.

Abstract: A tube of porous PTFE having at least two first and at least two second regions wherein the at least two first regions have a greater density than the at least two second regions. For tubes of porous expanded PTFE having a microstructure of nodes interconnected by fibrils, the at least two first regions have a mean fibril length that is less than that of the at least two second regions. Preferably the regions are arranged in the form of ring-shaped segments of the tube wherein denser segments alternate along the length of the tube with less dense segments. Other arrangements between the different regions are possible; for example, the regions may be oriented in a spiral relationship with each other along the length of the tube. The porous PTFE tubes of the present invention have excellent radial compression resistance without requiring additional exterior reinforcing members due to the presence of the denser regions that are provided with a circumferential orientation.