A New Physical Model and Anti-Fog Technology for Undistorted Visualization through Endoscope Lenses using Sterile, Benign, Hyper-Hydrophilic Gel Coatings to Planarize and Absorb Condensing Water*

Fogging on endoscope lenses limits visualization in closed body cavity surgery, due to differences in body temperatures vs Operating Rooms (OR). Surgeons have to remove and reinsert endoscopes, which increases infections, scarring, surgery durations, and costs.

Fogging is due to discontinuous 3D films formed by (hemi-) spherical drops refracting light.

The present anti-fog model and technology, KnoxFog™, uses hyper-hydrophilic [1] coatings. Hyper-hydrophilicity combines super-hydrophilicity [2-4] with "absorbing nanopores".

Super-hydrophilicity condenses water into continuous, flat, clear 2-D film [2] . Absorbing nanopores consist of a uniform hydrophilic network of nanopores drawing molecules into the material, which evacuates condensating water by molecular absorption. Combining super-hydrophilicity with absorbing nanopores maintains condensating water films flat and uniform, free of optical distortion, and inhibits water runoff into large drops. Hyper-hydrophilicity impedes two types of droplet formation – fog and run-off.

Current anti-fog strategies are insufficient. Acidic and alcohol-based anti-fog solutions quickly evaporate. Heating endoscopes requires reheating every 5 to 40 min [2, 4-8].

Hyper-hydrophilic KnoxFog™ is applied as a solid gel via a small, sterile, reusable, applicator, ClearEndoscope™, and dries in seconds.

In vitro comparison with eight endoscopes shows imaging is fog-free for hours with KnoxFog™ vs bare lenses, lens heating and other anti-fogs.