VISION PRESERVATION SYSTEM FOR MEDICAL DEVICES

The present disclosure relates to vision preservation systems for medical devices, such as cryospray devices for use with endoscopes. Exemplary embodiments provide a distal attachment in the form of a shroud or cap that mounts to the end of a flexible endoscope. A purging fluid supply mechanism is provided along the length of the endoscope, providing a channel for purging fluid, such as gas, to communicate between the endoscope tip and an external gas supply. The cap or shroud assembly incorporates a lens clearing flow field adjustment mechanism, such as nozzles, designed to direct warm (room temperature or higher) purging fluid across a lens at the scope tip. Another flow deflection mechanism, such as a guide or nozzle, may be included with the cap to direct purging fluid at an angle away from the lens. Gas, as an example, directed across and toward the lens purges moisture to avoid condensation on the lens and shears debris and bodily fluids away from the field of view. Gas directed or deflected by a guide away from the lens serves the purpose of keeping incoming particles and fluid droplets (e.g. spatter) from impacting on the lens cover. The cap and shroud are designed to avoid entraining moist air from the body cavity or lumen being treated.