| 摘要 |
A cannula (100) includes a tubular body (102) having a proximal end (104) and distal blunt end (106), at least one lumen (108) extending the length of the body (102), an endoscope (110) having a lighted, viewing end (112) disposed in the lumen (109) near the distal end (106) of the body (102), and a transparent, tissue separating tip (122) substantially covering the distal end of the body. The tissue separating tip (122) is slightly blunted to inhibit avulsion of tissue and lateral vessels along the dissected cavity formed thereby. Endoscopic viewing through the tip is enhanced by tapering the inner walls thereof to a cusp (120) adjacent the blunt tip in order to reduce visual distortion. Alternatively, a cannula includes a dissection probe (907) and endoscope (110) to facilitate viewing and the dissection of connective tissue and lateral vessels along the dissectible cavity. |
