Collapsible liquid reservoir

An irrigation device comprising:

• a collapsible reservoir, comprising:
• a top including an opening;
• a bottom wall;
• and
• a flexible side wall having a plurality of steps, wherein the steps are of progressively smaller outer dimension from a bottom step to a top step, each of the steps comprising a riser segment and a tread segment pivotably connected to one another at an external hinge, the tread of at least one step being pivotably connected to the riser of an adjacent step at an internal hinge, and the step segments joined to the internal hinge being symmetrical about a bisector of said internal hinge such that the steps nest inward from the bottom step when collapsed;
• an irrigation catheter;
• and
• a tubing one end of which is operably connected to the reservoir and the other end connected to the irrigation catheter.

An irrigation device comprising:

• a collapsible reservoir, comprising:
• a top including an opening;
• a bottom wall;
• and
• a flexible side wall having a plurality of steps, each of the steps comprising a riser segment and a tread segment pivotably connected to one another at an external hinge, the tread of at least one step being pivotably connected to the riser of an adjacent step at an internal hinge, wherein the steps are of progressively smaller outer dimension from a bottom step to a top step such that the steps nest inward from the bottom step when collapsed, the flexible side wall having the shape of a truncated pyramid having a generally square base and four trapezoidal side panels joined to one another at corners;
• an irrigation catheter;
• and
• a tubing one end of which is operably connected to the reservoir and the other end connected to the irrigation catheter.