摘要:
A balloon catheter having a multi-layered balloon which has a first layer and at least a second layer, and which has noncompliant limited radial expansion beyond the nominal diameter of the balloon. By selecting the polymeric materials forming the balloon layers, and arranging and radially expanding the multiple layers of the balloon in accordance with the invention, a balloon is provided having an improved low compliance, preferably in combination with high flexibility and softness.
摘要:
Tubing made of two or more polymers circumferentially arranged around the perimeter of the tubing in a single layer may be useful as medical tubing. Specifically, such tubing may be useful in catheters, sheaths, sheath introducers, implant delivery systems, and other medical devices having elongated tubular components. Selection of the two or more polymers based on the durometer and melting temperature permits optimization of axial strength and flexibility for particular applications. Such tubing may be extruded as a single layer tubing or a multi-layer tubing where the additional layers may be single material layers or more multi-polymer layers.
摘要:
The present invention relates to silicone hydrogels formed from mixtures comprising one or more hydrophilic high molecular weight polymers, one or more hydroxyl-functionalized silicone containing monomers, one or more crosslinkers and a compatabilizing diluent, but without a substantial amount of a reactive hydrophilic monomer or macromer.
摘要:
A silicone composition having anti-microbial properties contains well distributed silica and nanoparticles of a noble metal. Silica and nanoparticles of a noble metal are added to liquid vinyl-terminated polydimethylsiloxane. A coupling agent is then added to the mixture and heated, the coupling agent comprising trialkoxysilane having a formula R1Si(OR2)3, wherein R1 is vinyl or allyl, and R2 is an alkyl radical having from 1 to 3 carbon atoms. In one embodiment, trimethylsiloxy terminated polymethylhydrosiloxane is then added to the mixture and heated in the presence of a catalyst so as to cross-link and cure the same into a silicone elastomer. In another embodiment, in place of the trimethylsiloxy terminated polymethylhydrosiloxane, a peroxide is added to mixture and heated to form the silicone. In this later example, no catalyst is needed.
摘要:
Implant devices for intravesical administration and local drug delivery. The device has a body which includes a hollow tube formed of a biocompatible material; at least one reservoir in the tube which contains a drug; and one or more apertures through which the drug can be released. The device is configured for minimally invasive insertion into a body cavity, such as the bladder. The hollow tube may be elastomeric to permit the device to be elastically deformed from its initial shape into an elongated shape for passage through a catheter, where following such passage the device can return to or toward its initial shape to facilitate retention of the device in the body cavity. The body may have a narrow, elongated shape effective to permit insertion of the drug delivery device through a catheter without necessarily deforming the body, yet include flexible projections which effect retention within the body cavity.
摘要:
A catheter balloon and method involves extruded tubing with multiple layers of different durometer values, selected such that the blow up ratio (BUR) at the balloon's inner surface is increased. In one method a two stage blow mold process uses a small radius initial stage where radial growth is limited, followed by a second stage to a final dimension. A single stage blow mold process is also disclosed where the materials and processing are selected to approach the elongation to failure limit of the material. The single stage approach is preferably followed by a modified post-expansion heat set treatment to promote greater axial strength, leading to a preferred failure mode in the axial rather than radial direction.
摘要:
A multilayer balloon catheter is formed to have an inner layer and an outer layer, where the outer layer is adapted to resist shredding and premature rupture. The outer layer is formed of a material having a glass transition temperature that is lower than the transition or melting temperature of the inner layer. By forming the balloon on a mold at a temperature between the glass transition temperature of the outer layer and the glass transition or melting temperature of the inner layer, the outer layer will undergo a thermal relaxation that will alleviate some of the axial orientation of the polymer chains that develop during the formation of the multilayer balloon. This relaxation leads to a resistance to shredding when the balloon is expanded during operation.
摘要:
A method for producing a bioactive surface on an endoprosthesis, or on the balloon (3) of a balloon catheter (1) is described, wherein the surface (15) of the endoprosthesis, or the surface (4) of the balloon (3) is softened. The surface (15) of the endoprosthesis, or the surface (4) of the balloon (3) is moistened with a solution (6) of an active ingredient (7), and the solvent (8) is separated from the active ingredient (7). In addition, a balloon (3) of a balloon catheter (1) is disclosed, which comprises an uncoated surface (4), wherein an unencapsulated active ingredient (7) is embedded at least partially into the material of the surface (4). Furthermore, a balloon catheter (1) is described, which comprises a balloon (3) according to the invention. In addition, an endoprosthesis, particularly a polymer stent is described, which comprises an uncoated surface (15), wherein an active ingredient (7) is embedded at least partially into the material of the surface (15).
摘要:
The present invention refers to medical devices comprising a modified polyamide or to modified polyamides or modified polyamide elastomers with the polyamides having high flexibility and high stress resistance, especially tensile strength or tear resistance, in addition to the good physical characteristics of the known polyamide elastomers.