| abstract |
A medical device for cryotreatment of bodily regions is disclosed. The device comprises an inflatable support structure coupled to the distal end portion of a catheter shaft, the support structure being further enveloped by an expandable membrane to define an expansion chamber between the support structure and the membrane. An inflation lumen is coupled to the support structure to inject an inert, insulating fluid in the support structure, thereby expanding the support structure and the expandable membrane, wherein the resultant expansion chamber formed therebetween is substantially conical in shape. Refrigerant is injected into the expansion chamber, thereby creating localized cooling of tissues adjacent to the expansion chamber, the cooling region being substantially conical in shape. Alternately, a second inflatable support structure is provided inside of the expandable membrane and distal to the first support structure, to define an expansion chamber therebetween that is substantially toroidal in shape, thereby enabling the creation of circumferential cooling regions when refrigerant is injected into said expansion chamber. |