| 摘要 |
A retractor (112) and a surgical tool (120) are positioned within a cannula (100), and a dissection cradle (116) of the retractor (112) is positioned at the distal end (122) of the cannula (100). The retractor (112) includes a first portion (110) with an axis approximately parallel to the axis (101) of the cannula (100) and a second portion (114) with an axis (115) at an angle (117) to the axis (101) of the cannula (100). The dissection cradle (116) is located at the distal end of the second portion (114) of the retractor (112), and may include two substantially parallel, spaced legs (141,142) with the retractor shaped in a loop between and in a plane skewed relative to the axis of the legs (141,142), and with the loop directed away from the surgical tool (120). Thus, in operation, when the surgeon locates a vein (118) and side branch of interest, the surgeon extends the retractor (112) to cradle the vein (118) in the dissection cradle (116). Once cradled, the retractor (112) may be fully extended to urge the vein (118) away from the axis of the cannula (100) isolate the side branch for exposure to the surgical tool (120). In another embodiment, the cannula includes a sheath which encases the curved, resilient retractor at a first position to retain the retractor in substantially straight orientation, and which encases the retractor at a second position that allows the retractor to extend at an angle relative to the axis of the cannula. <IMAGE> |
