Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
100 words
An instrument for retaining a desired inner diameter of a tubular organ lumen (11), comprising a cylindrical member (10;20;30;40) made of a unidirectional shape memory alloy whose transformation temperature is higher than the temperature of a living body in which the cylindrical member is to be placed, characterized in that said cylindrical (10;20;30;40) member is radially expandable by an external force at said temperature of said living body, and in that the outer diameter of said cylindrical member in its basic phase when heated to said transformation temperature, is smaller than the inner diameter of said tubular organ lumen (11).
Claim 2
Dependent Claim
100 words
An instrument for retaining a desired inner diameter of a tubular organ lumen (11), comprising a cylindrical member (10;20;30;40) made of a unidirectional shape memory alloy whose transformation temperature is higher than the temperature of a living body in which the cylindrical member is to be placed, characterized in that said cylindrical (10;20;30;40) member is radially expandable by an external force at said temperature of said living body, and in that the outer diameter of said cylindrical member in its basic phase when heated to said transformation temperature, is smaller than the inner diameter of said tubular organ lumen (11).
Claim 3
Dependent Claim
15 words
An instrument according to claim 1, wherein said cylindrical body comprises a coil-like body (10).
Claim 4
Dependent Claim
18 words
An instrument according to claim 1, wherein said cylindrical body comprises a body (20) having a spiral section.
Claim 5
Dependent Claim
22 words
An instrument according to claim 1, wherein said cylindrical body comprises a tubular body (30) having slit in a longitudinal direction thereof.
Claim 6
Dependent Claim
15 words
An instrument according to claim 1, wherein said cylindrical body comprises a mesh-like body (40).
Claim 7
Dependent Claim
25 words
An instrument according to claim 1 or 5, wherein said cylindrical body is constituted by a fabric made of a shape memory alloy thin wire.
Claim 8
Dependent Claim
31 words
An instrument according to any one of the preceding claims, wherein said unidirectional shape memory alloy consists of an alloy selected from the group consisting of Ti-Ni, Cu-Al-Ni, and Cu-Zn-AI alloys.
Claim 9
Dependent Claim
122 words
Use of an instrument according to any one of the preceding claims for keeping the desired inner diameter of a tubular organ lumen (11), wherein the instrument (10) is introduced in said tubular organ lumen in its basic phase with a diameter smaller than the desired inner diameter, plastic deformation of the instrument is performed by an external force applied to said cylindrical member so as to expand it radially at said desired inner diameter; and afterwards, when the position of the indwelled instrument is to be changed or the instrument is to be recovered, heat is applied to said cylindrical member (10), so as to exceed the transformation temperature, the basic phase of the unidirectionnal shape memory alloy being thus restored.