Patent ID: 7537580

Claim:
A medical device comprising: a catheter, the catheter having at least one catheter shaft, the at least one catheter shaft defining an inflation lumen for transport of an inflation fluid therethrough, the inflation fluid comprising a coolant; an expandable balloon, the balloon having a proximal cone, a distal cone and a body region therebetween, the balloon being engaged to a distal region of the at least one catheter shaft, the balloon defining an exterior and an interior, the interior being in fluid communication with the inflation lumen, a portion of the catheter shaft distal of the balloon defining at least one shaft exit port and a portion of the catheter shaft within the balloon defining at least one port in fluid communication with the inflation lumen and the balloon interior; a baffle positioned on the balloon interior proximal to the distal cone and disposed about said at least one catheter shaft, the baffle extending radially outward from said shaft to engage said balloon, the baffle further defining one or more baffle openings therethrough, the one or more baffle opening longitudinally or radially offset from a distally adjacent balloon opening; wherein the baffle is constructed and arranged to permit the exit of fluid from the balloon interior through the plurality of ports to the balloon exterior but limit the entrance of bodily fluid from entering the balloon interior from the balloon exterior during deflation.