LAUSR

Coronavirus disease (COVID-19) transmission occurs primarily through direct contact or air droplets [1, 2], and endoscopic procedures are high risk. In this era of “with COVID-19,” establishing simple infection prevention measures within an endoscopy department to protect both patients and personnel is strongly recommended. Hence, we proposed a simple method using a modified surgical mask. We made a hole (10mm diameter) in the center of a surgical mask (▶Fig. 1). Next, simulated endoscopy was performed with and without the modified surgical mask using a mannequin with the mouthpiece in place (▶Video 1). Cough was simulated using a 0.4-MPa pressure accumulation sprayer containing 10mL of fluorescent dye [3–5]. An endoscopist (height 173 cm) wearing standard personal protective equipment (PPE) performed upper gastrointestinal endoscopy. A nurse (height 163 cm) wearing standard PPE stood on the other side of the “patient.” The scattered dye droplets produced by the simulated cough were visualized using ultraviolet light. Without the modified surgical mask, contamination of the floor occurred within approximately 1.5m from the bed, and the dye was clearly identified on the gloves, right arm, upper chest, abdomen, and shoe covers of the endoscopist (▶Fig. 2). There was no dye on the endoscopist’s eye shield, mask, or cap. The dye was identified on the gloves of the nurse (▶Fig. 3). When the modified surgical mask was worn by the “patient,” excesE–Videos