Devices and methods for soft tissue and endovascular material removal
A soft tissue biopsy or material collection device may comprise a work element consisting of an outer tube with external sheath and formed from a tapered helical structure over an internal tube structure configured to open and close its distal end to perform penetration, coring, capturing, parting off and transporting multiple material samples in a single or multiple insertion procedure.
1. A device, comprising:
an internal tube element, sharpened at a distal edge thereof, configured to cut and core tissue;
a wound helical coil outer tube element, disposed over the internal tube element, and comprising a distal portion that extends distally beyond the internal tube element in a tapered configuration, such that constituent helical coils thereof define progressively smaller diameters as a distance from the sharpened distal edge of the internal tube element increases, wherein differential rotation of the wound helical coil outer tube element relative to the internal tube element selectively:
retracts the distal tapered portion of the wound helical coil outer tube element to expose and enable the sharpened distal edge of the internal tube element to core tissue; and
returns the distal tapered portion of the wound helical coil outer tube element to the tapered configuration, enclosing the sharpened distal edge of the internal tube element and parting off cored tissue from surrounding tissue.
2. The device of claim 1 , wherein the internal tube element comprises a wound coil.
3. The device of claim 2 wherein, near a distal portion thereof, the wound coil of the internal tube element comprises helical coils that are fused together.
4. The device of claim 1 , further comprising an outer sheath that is disposed at least partially over the wound helical coil outer tube element.
5. The device of claim 1 , wherein the wound helical coil outer tube element is formed from a single tube that is laser-cut to form the constituent coils thereof.
6. The device of claim 1 , wherein the wound helical coil outer tube element comprises a tightly wound tapered spring.
7. The device of claim 1 , wherein at least one of the internal tube element and the wound helical coil outer tube element comprise stainless steel.
8. The device of claim 1 , wherein the distal portion that extends distally beyond the internal tube element in a tapered configuration is shaped so as to facilitate tissue penetration and parting off cored tissue.
9. The device of claim 1 , further comprising a side-supporting expandable element disposed near a distal end of the device that is configured to steer the distal end of the device within tissue.
10. The device of claim 1 , wherein the wound helical coil outer tube element defines an internal lumen and wherein the internal lumen is substantially smooth to facilitate transport of cut cored tissue.