Abstract: A surgical retractor assembly for providing a generally constant retracting force at a fixation site on a patient despite possible movements of the fixation site during application of the retracting force. The retractor assembly comprises a support structure engaging element for providing communication between the surgical retractor assembly and a support structure; a retractor guide for receiving a first end of a retracting member, the retractor guide being coupled to the support structure engaging element, wherein the retractor guide is displaceable relative to the support structure engaging element; and a biasing structure that provides the retracting force.

Abstract: A needle biopsy system (10) includes a biopsy needle (210), and a needle support assembly (200). The needle support assembly (200) holds the biopsy needle (210) and manipulates the biopsy needle (210) in response to received control signals. A needle simulator (250) having an input device (252) generates the control signals in response to manipulation of the input device (252) by an operator. The operator, in turn, receives feedback from the needle simulator (250) in accordance with forces experienced by the biopsy needle (210). In a preferred embodiment, the feedback received by the operator includes tactile sensations experienced by the operator as the operator manipulates the input device (252). The tactile sensations mimic those the operator would have received had the operator directly manipulated the biopsy needle (210). Optionally, a curved needle guide (280) is employed to restrict the biopsy needle's progression longitudinally therethrough.

Abstract: An imaging apparatus (18) includes a frameless stereotactic arm apparatus (30) including a first base portion (42) mounted in a fixed relationship to the imaging device. A second free end (40) of the arm assembly is adapted to move into varied positions near a specimen disposed on the imaging apparatus. At least one pivot joint (44, 48, 52, 56, 60) is provided between the first base portion and the free end of the arm for permitting selective relevant movement between the arm members. Electro-mechanical and electro-magnetic brake devices are provided at respective joints to selectively lock the free end of the arm assembly to the base portion. The brakes are responsive to a brake command signal (210) generated by the imaging device. A low pass filter (240) conditions the brake command signal to substantially eliminate high frequency electromagnetic switching noise in the stereotactic arm.