Tissue removal device and method of use
A biopsy device for acquiring more than one tissue sample is disclosed. The biopsy device can have at least two tissue engaging elements, where at least one element contains a helical feature. A control mechanism can be used to spin an outer element relative to an internal element, resulting in transport of multiple tissue samples from the mass of tissue to an accessible collection chamber. The outer element may have a sharp distal end which may sever the samples from the mass of tissue. Samples may be stored sequentially in the collection chamber and be removed by the operator.
1. A tool for acquiring a tissue at a tissue site comprising:
a tissue-engaging outer element comprising a substantially tubular structure having a lumenal cross-sectional area; and
a tissue-engaging inner element located at least partially within the tissue-engaging outer element; wherein at least one of the tissue-engaging outer element and the tissue-engaging inner element comprises a helical feature,
wherein the tool is configured such that relative rotation between the tissue-engaging outer element and the tissue-engaging inner element urges the tissue in an axial direction, and wherein the tissue-engaging inner element occupies less than 15% of the lumenal cross-sectional area,
wherein the tissue-engaging outer element has an open first end and an open second end,
wherein the tissue-engaging outer element is configured to receive the tissue in the first end and deposit the tissue out of the second end,
wherein the second end is configured to be open to atmospheric pressure, and
wherein the relative rotation between the tissue-engaging outer element and the tissue-engaging inner element transports the tissue from the first end out of the second end.
2. The tool of claim 1 wherein the tissue-engaging inner element occupies less than 5% of the lumenal cross-sectional area.
3. The tool of claim 1 wherein the tissue-engaging inner element occupies less than 2.5% of the lumenal cross-sectional area.
4. The tool of claim 1 , wherein a terminal distal end of the tissue-engaging outer element is sharpened and configured to core the tissue from the tissue-site when the tissue-engaging outer element rotates with respect to the tissue site; and wherein the tissue-engaging inner element comprises a coiled wire having a circular cross-section.
5. The tool of claim 1 , wherein the tissue-engaging outer element has a tissue-contacting first surface and the tissue-engaging inner element has a tissue-contacting second surface, and wherein at least one of the tissue-contacting first surface and the tissue-contacting second surface comprise a surface feature, and
wherein the surface feature comprises at least one of spiral ribs, helical ribs, axial ribs, rifling, knurling, ridges, spines, barbs, coatings, texturing, an overlapping tube, overlapping tubes, a ribbon, and ribbons.
6. The tool of claim 1 , wherein the tissue-engaging inner element is configured to transport a supplemental device or therapy at least one of distally and proximally along the tissue engaging outer element.
7. The tool of claim 1 , wherein the helical feature extends from a distal end to a proximal end of the tissue-engaging outer element or the tissue-engaging inner element.