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US 4,969,890 AGranted
Catheter
AssigneeNippon Zeon Co., Ltd.
InventorsYoichi Sugita, Takashi Kawabata
Life of this patent
Estimating the term…
Abstract
There is provided a catheter composed of a main body fitted with a shape memory alloy member and having a liquid injection means to supply warming liquid to have said member recover the original shape thereof.
Claims9
A catheter for insertion of a shape memory alloy endoprosthesis into a stenosis comprising:
- a main body provided with an extensible balloon portion at a leading end thereof;
- a narrow body portion adjacent said balloon portion, fitted therearound with a cylindrical shape memory alloy endoprosthesis;
- a slightly wider body portion at an end of said narrow body portion opposite said balloon portion, forming a bulge portion projecting thereat;
- a first lumen passing through said main body and terminating in said balloon portion for injection fluid into said balloon portion to cause inflation thereof;
- a second lumen passing through said main body to a distal end, through which a guide wire can pass;
- and
- a sheath substantially covering said main body except for said balloon portion, said sheath forming a third fluid injection lumen defined by an inner surface of said sheath and outer surface of said main body and having an inlet port provided at a rear end thereof to supply a warming fluid to said endoprosthesis located inside a front part of said sheath at said narrow body portion, at a temperature above a transition point of the shape memory alloy, to cause recovery of an original shape of said endoprosthesis.
4 more elements
A catheter for insertion of a shape memory alloy endoprosthesis into a stenosis comprising:
- a main body provided with an extensible balloon portion at a leading end thereof;
- a narrow body portion adjacent said balloon portion, fitted therearound with a cylindrical shape memory alloy endoprosthesis;
- a slightly wider body portion at an end of said narrow body portion opposite said balloon portion, forming a bulge portion projecting thereat;
- a first lumen passing through said main body and terminating in said balloon portion for injecting fluid into said balloon portion to cause inflation thereof;
- a second lumen passing through said main body to a distal end, through which a guide wire can pass;
- and
- a fluid injection means to inject fluid at said narrow body portion to provide irrigation thereat for causing recovering of an original shape of said shape memory alloy endoprosthesis;
- wherein said shape memory alloy endoprosthesis comprises a shape memory alloy metal, said metal being preformed into a cylindrical shape, said metal having been subjected to an annealing process such that when later deformed the metal will be restored to said original preformed cylindrical shape when subjected to a transition temperature, and a further treatment to cause longitudinal end regions of the endoprosthesis to have a higher transition temperature than a middle region such that when said metal is subjected to said transition temperature said regions of said metal will be restored to said original preformed cylindrical shape at different rates.
5 more elements
A catheter for insertion of a shape memory alloy endoprosthesis into a stenosis comprising:
- a main body provided with an extensible balloon portion at a leading end thereof;
- a narrow body portion adjacent said balloon portion, fitted therearound with a cylindrical shape memory alloy endoprosthesis;
- a slightly wider body portion at an end of said narrow body portion opposite said balloon portion, forming a bulge portion projecting thereat;
- a first lumen passing through said main body and terminating in said balloon portion for injecting fluid into said balloon portion to cause inflation thereof;
- a second lumen passing through said main body to a distal end, through which a guide wire can pass;
- and
- a fluid injection means to inject fluid at said narrow body portion to provide irrigation thereat for causing recovery of an original shape of said shape memory alloy endoprosthesis;
- wherein said shape memory endoprosthesis is a tubular metal sheet such that upon recovery of said original shape the endoprosthesis changes in diameter but not substantially in longitudinal dimension during shape change, said endoprosthesis having a plurality of holes formed in the surface thereof providing openings for contact with tissue.
5 more elements
A method applying a shape memory metal alloy endoprosthesis to a stenosis comprising the steps of:
- (a) applying a shape memory metal alloy endoprosthesis preformed into cylindrical shape to a narrow body portion of a catheter having a main body portion provided at a leading end thereof with an extensible balloon portion, said endoprosthesis being applied by wrapping said metal about said narrow body portion in a cylindrical form of smaller diameter than said preformed cylindrical shape;
- (b) inserting said catheter into a body passage as far as a stenosis thereof, said balloon portion extending beyond said stenosis;
- (c) inflating said balloon portion to contact an inner wall of said body passage beyond said stenosis so as to stop any flow of body fluid thereon;
- (d) after said balloon portion is inflated, injecting a warming fluid through a lumen in said catheter surrounding the area of said endoprosthesis, said fluid being of temperature such as to restore said endoprosthesis to said original preformed shape to dilate said stenosis;
- (e) deflating said balloon portion of said catheter;
- and
- (f) removing said catheter, said endoprosthesis remaining in said stenosis.
4 more elements
Dependencies are inferred from the claim text.