Two way shape memory alloy medical stent
First Claim
1. A stent for placing in a portion of a tubular organ so as to support the walls of the tubular organ in said portion such that the tubular organ in said portion will have a diameter above a critical diameter, the stent comprising:
- a spiral coil or cylinder made of a two-way shape memory alloy;
having a super-elastic scale in which the stent has a first diameter which is at least about the critical diameter but within a physiological range tolerated by said organ; and
having a soft state in which the stent has a second diameter, after changing to this state from the super-elastic scale, which is less than said critical diameter;
the shape memory alloy has two transition temperatures being within a range that will not damage biological tissue, of which a first transition temperature, being a temperature which is above body temperature, is a temperature in which said alloy changes from said soft state to said super-elastic state and of which a second transition temperature, being a temperature which is below body temperature, is a temperature in which said alloy changes from said super-elastic state to said soft state, so that after changing into one of the two states, the stent remains in that state at body temperature.
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Accused Products
Abstract
A stent for placing in a tubular organ so as to support its diameter to remain above a critical diameter. The stent comprises a spiral coil or cylinder made of a two-way shape memory alloy and has a super-elastic state in which the stent'"'"'s diameter is at least about the critical diameter or more but within a physiological range tolerated by the organ and having a soft state in which the stent'"'"'s diameter, after changing to this state from the super-elastic state, which is less than the critical diameter. The shape memory alloy has two transition temperatures being within a range that will not damage biological tissue, of which a first transition temperature is a temperature in which it changes from the soft state to the super-elastic state and of which a second transition temperature is a temperature in which it changes from the super-elastic state to the soft state. The arrangement being such that after changing into one of the two states, the stent remains in that state at body temperature.
515 Citations
11 Claims
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1. A stent for placing in a portion of a tubular organ so as to support the walls of the tubular organ in said portion such that the tubular organ in said portion will have a diameter above a critical diameter, the stent comprising:
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a spiral coil or cylinder made of a two-way shape memory alloy;
having a super-elastic scale in which the stent has a first diameter which is at least about the critical diameter but within a physiological range tolerated by said organ; and
having a soft state in which the stent has a second diameter, after changing to this state from the super-elastic scale, which is less than said critical diameter;the shape memory alloy has two transition temperatures being within a range that will not damage biological tissue, of which a first transition temperature, being a temperature which is above body temperature, is a temperature in which said alloy changes from said soft state to said super-elastic state and of which a second transition temperature, being a temperature which is below body temperature, is a temperature in which said alloy changes from said super-elastic state to said soft state, so that after changing into one of the two states, the stent remains in that state at body temperature. - View Dependent Claims (2, 3, 4)
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5. A catheter device for deploying a stent in a tubular organ, such that the stent will support walls of the tubular organ to secure that the tubular organ will have a critical diameter above a critical diameter comprising a catheter tube or rod carrying a stent coiled on an end segment of the tube or rod, the stent comprising:
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a spiral coil or cylinder made of a two-way shape memory alloy;
having a super-elastic state in which the stent has a first diameter which is at least about the critical diameter but within a physiological range tolerated by said organ; and
having a soft state in which the stent has a second diameter, after changing to this state from the super-elastic state, which is less than said critical diameter;the shape memory alloy has two transition temperatures being within a range that will not damage biological tissue, of which a first transition temperature, being a temperature which is above body temperature, is a temperature in which said alloy changes from said soft state to said super-elastic state and of which a second transition temperature, being a temperature which is below body temperature, is a temperature in which said alloy changes from said super-elastic state to said sort state, so that after changing into one of the two states, the stent remains in that state at body temperature; the stent carried on the catheter tube or rod in said soft state. - View Dependent Claims (6, 7, 8, 9, 10, 11)
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Specification