A method of biopsy device operation comprises rotating a first rotating member at a first rotational speed to rotate a cutter. A second rotating member is rotated at a second rotational speed to translate the cutter. The first and second members are rotated simultaneously and in the same direction. The first rotating member rotates with the cutter, while the second rotating member rotates about the first rotating member. The difference between the first and second rotational speeds, as well as threaded engagement between the first and second rotating members, provides the translation of the cutter. A method of biopsy device operation also comprises moving a shuttle valve slider to selectively vent or seal the second lumen of a needle. The shuttle valve slider is responsive to translation of the cutter, though some degree of lost motion is provided between the shuttle valve slider and the cutter.
