| 摘要 |
<p>A trocar having a needle unit (5). The needle unit (5) has a paracentetic section (18), which is substantially pyramidal. The paracentetic section (18) has two curved surfaces (21a and 21b) that diagonally oppose each other. The surfaces (21a and 21b) have been formed by cutting the ridges (20a and 20b) of the section (18), which diagonally oppose each other. The remaining two ridges (22a and 22b) of the paracentetic section (18) make, respectively, sharp cutting edges (23a and 23b) for cutting living tissues. The cutting edges (23a and 23b) are substantially symmetrical to each other with respect to the axis of the needle unit (5). <IMAGE></p> |
