Method of use for percutaneous material removal device and tip

A method of removing material from a preselected body lumen in a patient in need of such removal, comprising:

• advancing through said preselected body lumen a catheter-mounted device having a distal material removal tip including a hollow housing, a shearing member and a member rotatable therewithin, wherein said rotatable member includes grinding means for grinding said material prior to said contact of said material with said shearing member, wherein said grinding means include at least one abrasive surface fabricated from at least one abrasive material selected from the group consisting of ceramics, diamond, quartz, silicon carbide, aluminum oxide, boron carbide, boron nitride, tungsten carbide, titanium nitride, titanium surfaces with a file-like surface, and stainless steel surfaces with a file-like surface;
• rotating said rotatable member;
• grinding said material into ground material;
• drawing said ground material into said housing;
• shearing said material in said housing between the rotating rotatable member and shearing member, whereby the propensity of said material to clog said device is reduced;
• and
• removing said material from within said housing as said material removal tip is advanced through said preselected body lumen.