Abstract: An article includes walls defining an insulating space therebetween and a vent forming an exit for gas molecules during evacuation of the space. A distance separating the walls is variable in a portion adjacent the vent such that gas molecules are directed towards the vent imparting a greater probability of molecule egress than ingress such that deeper vacuum is developed without requiring getter material. The variable-distance portion may be formed by converging walls. Alternatively, a portion of one of the walls may be formed such that a normal line at any location within that portion is directed substantially towards a vent opening in the other wall.

Abstract: A heated fluid surgical instrument including a palm-sized handpiece having a cannula adapted to be inserted into a patient's body by way of a natural access (e.g., mouth) or a small incision. A channel is provided within the handpiece and the cannula for permitting the passage of a surgical accessory implement to the surgical site. Additional, channels are provided for passing fluid pumped into the handpiece from a remote fluid source to the surgical site. An irrigation control valve assembly on the handpiece permits a surgeon to selectively direct the flow of fluid through the handpiece and into one of two fluid flow paths. One of the paths heats the fluid and passes it to the surgical site to effect a therapeutic result. The other path sends the fluid directly to the surgical site.