Variable pitch flexible needle

Abstract

Disclosed embodiments include flexible tube assemblies, flexible needle assemblies, systems, methods of fabricating a flexible tube, and methods of fabricating a flexible needle. In an illustrative, non-limiting embodiment, a flexible tube assembly includes: a flexible tube having a proximal end with a proximal strain relief section and a distal end with a distal strain relief section, the proximal strain relief section being located between the proximal end and the distal strain relief section and the distal strain relief section being located between the distal end and the proximal strain relief section, the distal end defining an opening therein, at least a portion of at least one of the proximal strain relief section and the distal strain relief section defining therein a spiral cut with a continuously variable pitch; and tubing disposed in an airtight manner over an exterior surface of the flexible tube at least the portion of the at least one of the proximal strain relief section and the distal strain relief section defining therein the spiral cut with a continuously variable pitch.

1 - 20 . (canceled) 
     
     
         21 . An apparatus comprising:
 a flexible tube extending between a proximal end and a distal end, the flexible tube including:   a proximal strain relief section extending between a first proximal point toward the proximal end of the flexible tube and a first distal point toward the distal end and including a proximal spiral cut having a continuously variable pitch; and   a distal strain relief section extending between the first distal point and a second distal point toward the distal end and including a distal spiral cut having a constant pitch.   
     
     
         22 . The apparatus of  claim 21 , wherein the continuously variable pitch of the proximal strain relief section decreases from a first pitch at the first proximal point to a second pitch at the first distal point. 
     
     
         23 . The apparatus of  claim 22 , wherein the constant pitch of the distal strain relief section is equal to the second pitch at the first distal point. 
     
     
         24 . The apparatus of  claim 21 , further comprising a third strain relief section extending from the second distal point toward the distal end, wherein the third strain relief section includes a third spiral cut extending from the second distal point to a third distal point. 
     
     
         25 . The apparatus of  claim 24 , wherein the third spiral cut includes a second distal spiral cut having a second continuously variable pitch. 
     
     
         26 . The apparatus of  claim 25 , wherein the second continuously variable pitch of the second distal strain relief section increases from the second pitch at the second distal point to a third pitch at the third distal point. 
     
     
         27 . The apparatus of  claim 21 , wherein the distal end defines a tip configured to pierce tissue. 
     
     
         28 . The apparatus of  claim 21 , further comprising tubing disposed in an airtight manner over an exterior surface of at least a portion of the flexible tube including the proximal spiral cut and the distal spiral cut. 
     
     
         29 . The apparatus of  claim 28 , wherein the tubing includes heatshrink tubing. 
     
     
         30 . An apparatus comprising:
 a flexible tube extending between a proximal end and a distal end, the flexible tube including:   a proximal strain relief section extending between a first proximal point toward the proximal end of the flexible tube and a first intermediate point toward the distal end and including a proximal spiral cut having a first continuously variable pitch;   an intermediate distal strain relief section extending between the first intermediate point and a second intermediate point toward the distal end and including an intermediate spiral cut having a constant pitch; and   a distal strain relief section extending between the second intermediate point and toward the distal end, wherein the distal strain relief section includes a distal spiral cut extending from the second intermediate point to a distal point and having a second continuously variable pitch.   
     
     
         31 . The apparatus of  claim 30 , wherein the first continuously variable pitch of the proximal strain relief section decreases from a first pitch at the first proximal point to a second pitch at the first intermediate point. 
     
     
         32 . The apparatus of  claim 31 , wherein the constant pitch of the intermediate strain relief section is equal to the second pitch at the first intermediate point. 
     
     
         33 . The apparatus of  claim 32 , wherein the second continuously variable pitch increases from the second pitch at the second intermediate point to a third pitch at the third distal point. 
     
     
         34 . The apparatus of  claim 30 , wherein the distal end defines a tip configured to pierce tissue. 
     
     
         35 . The apparatus of  claim 30 , further comprising tubing disposed in an airtight manner over an exterior surface of at least a portion of the flexible tube including the proximal spiral cut, the intermediate spiral cut, and the distal spiral cut. 
     
     
         36 . The apparatus of  claim 35 , wherein the tubing includes heatshrink tubing. 
     
     
         37 . An apparatus comprising:
 a flexible needle extending between a proximal end and a distal end, the flexible tube including:   a proximal strain relief section extending between a first proximal point toward the proximal end of the flexible tube and a first distal point toward the distal end and including a proximal spiral cut having a continuously variable pitch;   a distal strain relief section extending between the first distal point and a second distal point toward the distal end and including a distal spiral cut having a constant pitch;   a tip configured to pierce tissue; and   tubing disposed in an airtight manner over an exterior surface of at least a portion of the flexible tube including the proximal spiral cut and the distal spiral cut.   
     
     
         38 . The apparatus of  claim 37 , wherein the continuously variable pitch of the proximal strain relief section decreases from a first pitch at the first proximal point to a second pitch at the first distal point. 
     
     
         39 . The apparatus of  claim 38 , wherein the constant pitch of the distal strain relief section is equal to the second pitch at the first distal point. 
     
     
         40 . The apparatus of  claim 37 , wherein the tubing includes heatshrink tubing.