| 摘要 |
The cannula comprises a housing for receiving the surgical instrument with an elastomeric septum seal 120 disposed therein with a septum seal 121 having an orifice 121h with a diameter no greater than the diameter of the surgical instrument to form a seal. A cannula tube is 130 connected to the housing and a zero closure valve 140 is disposed between the tube and the housing. An elastic ring 150, which may be a sponge, is disposed surrounding the elastomeric septum seal and is capable of changing its shape in accordance with the movement of the seal so as to enable the seal to maintain a tight seal around the surgical instrument when it is moved. The cannula may also comprise a protection member 160 comprising two members 160a, 160b having offset slits 160c and the seal may have an embossment 121p to reduce friction. |
