BACKGROUND:Laparoscopic lens fogging (LLF) hampers vision and impedes operative efficiency. Attempts to reduce LLF have led to the development of various anti-fogging fluids and warming devices. Limited literature exists directly comparing these techniques. We constructed a model peritoneum to simulate LLF and to compare the efficacy of various anti-fogging techniques. MATERIALS AND METHODS:Intraperitoneal space was simulated using a suction bag suspended within an 8 L container of water. LLF was induced by varying the temperature and humidity within the model peritoneum. Various anti-fogging techniques were assessed including scope warmers, FREDTM, ResoclearTM, chlorhexidine, betadine and immersion in heated saline. These products were trialled with and without the use of a disposable scope warmer. Vision scores were evaluated by the same investigator for all tests and rated according to a predetermined scale. Fogging was assessed for each product or technique 30 times and a mean vision rating was recorded. RESULTS:All products tested imparted some benefit, but FREDTM performed better than all other techniques. Betadine and ResoclearTM performed no better than the use of a scope warmer alone. Immersion in saline prior to insertion resulted in decreased vision ratings. The robotic scope did not result in LLF within the model. CONCLUSIONS:In standard laparoscopes, the most superior preventative measure was FREDTM utilised on a pre-warmed scope. Despite improvements in LLF with other products FREDTM was better than all other techniques. The robotic laparoscope performed superiorly regarding LLF compared to standard laparoscope.