Patent attributes
A structure for receiving surgical instruments for performing a surgical procedure on a body includes a passage through which the surgical instruments are inserted into the body. The passage has a proximal end and a distal end. An expandable portion enables an increase in the cross-sectional area of the distal end of the passage. The expandable portion has a contracted condition in which the cross-sectional area of the distal end of the passage has a first cross-sectional area. The expandable portion has an expanded condition in which the distal end of the passage has a second cross-sectional area greater than the first cross-sectional area. The second cross-sectional area is greater than a cross-sectional area of the proximal end of the passage when the expandable portion is in the expanded condition. A retaining mechanism resists movement of the expandable portion from the expanded condition toward the contracted condition during the surgical procedure. The retaining mechanism is released at the conclusion of the surgical procedure to permit movement of the expandable portion from the expanded condition toward the contracted condition for removal of the structure.
