In Vivo Clinical Animal Trials for an Anti-Fog Coating on Surgical Lenses

One major issue that surgeons face during closed body cavity surgery is fogging of the lens surfaces. The cloudy and opaque lens surface caused by water vapor present in closed body cavities forces the surgeon to repeatedly remove the endoscope, wipe it, and reinsert it back into the patient. This presents several risks such as increased surgery time, greater scarring, and an increased chance of infection. In order to address this issue, the development of the Thin Fluid Film Device (TFFD™) VitreOx™ aims to render the lens surface hydrophilic, whereas it is typically hydrophobic. By creating a hydrophilic polymeric nanomesh, the 3-D water droplets can be trapped to lie flatter, thus resulting in a flatter 2-D sheeting effect. The light can no longer be refracted at different angles off of the 3-dimensional water beads, thus eliminating the opacity of the lens surface.
Two animal trials were performed involving a rat and two pigs in order to prove the efficacy of VitreOx™ in addition to being compared with competitor, Covidien Clearify. A laparoscopy was performed on each animal, and the length of time that the endoscope took to fog was measured post product application. The results of the optimized animal clinical trials involving two Yucatan pigs showed that the scope treated with Covidien’s Clearify began fogging within 8 minutes and continued to do so for the remained of the surgery, as opposed to the scope with VitreOx™ which remained fog free for the full 90-minute procedure. The results proved the efficacy of our product.
The second part of the thesis aimed to optimize HemoClear™, the blood evacuating TFFD™. This was done by testing a higher concentration of 6 mg/mL fibrinogen as compared to previous work. After conducting an experiment designed to mimic closed-body cavity surgery it was determined that the HemoClear™ eliminated fog 67% of the time and evacuated blood with a success of 83%. Future work aims to continue testing at this concentration with variances in mixing and application technique.