Hollow tube body for medical tool and a catheter into which the hollow tube body is incorporated

Abstract

A hollow tube body for medical tool has a plurality of metallic wires ( 2 ) cylindrically stranded to form a flexible tube. An inner surface of the flexible tube forms a convex-concave structure represented by the metallic wires ( 2 ) formed semi-circular in corss section. A leading distal end of the flexible tube is formed into a knife-edge circle configuration to provide a knife-edge circle front ( 3 ). The hollow tube body is used for catheters (K, K 1 , K 2 and K 3 ) to impart them with a perforative ability so as to improve its quality and performance.

What is claimed is:  
     
         1 . A hollow tube body for medical tool comprising: 
 a plurality of metallic wires cylindrically stranded to form a flexible tube, an inner surface of which forms a convex-concave structure represented by said metallic wires each formed semi-circular in corss section; and    a leading distal end of said flexible tube being formed into a knife-edge circle configuration to provide a knife-edge circle front.    
     
     
         2 . The hollow tube body for medical tool according to  claim 1 , wherein a blade edge of said knife-edge circle front is outwardly arcuated in cross section, and diametrically decreases progressively as approaching outward.  
     
     
         3 . The hollow tube body for medical tool according to  claim 1 , wherein a rigid-flexible property of said flexible tube gradually changes in the lengthwise direction.  
     
     
         4 . A catheter comprising: 
 a hollow tube body for medical tool including a plurality of metallic wires cylindrically stranded to form a flexible tube, an inner surface of which forms a convex-concave structure represented by said metallic wires each formed semi-circular in corss section; and a leading distal end of said flexible tube being formed into a knife-edge circle configuration to provide a knife-edge circle front;    said hollow tube body being applied at least partly to a mono-layered main tube body.    
     
     
         5 . A catheter according to  claim 4 , wherein multi-layered tube structure is formed by slidably fitting an upper-layered tube onto a lower-layered tube of a main tube body, and at least one of said upper-layered tube and said lower-layered tube is applied at least partly to said hollow tube body.  
     
     
         6 . The catheter according to  claim 5 , wherein an outer tube is slidably fit onto said upper-layered to form a three-layered structure, and a self-expansible stent mounted on said lower-layered tube is arranged to be pushably set and detachably released by means of said outer tube.  
     
     
         7 . The catheter according to  claim 6 , wherein a stranding direction of metallic wires of said lower-layered tube and that of said upper-layered tube are mutually opposite, otherwise a stranding direction of metallic wires of said upper-layered tube and that of said outer tube are mutually opposite.  
     
     
         8 . The catheter according to  claim 6 , a rigidity of which progressively increases in such a direction from said lower-layered tube to said upper-layered tube, otherwise said rigidity progressively increases in such a direction from said lower-layered tube to said outer tube.  
     
     
         9 . The catheter according to  claim 6 , wherein a manipulating portion of said lower-layered tube and said upper-layered tube, or a manipulating portion of said lower-layered tube, said upper-layered tube and said outer tube are connected in a row to a handling section.