Differences in incision shape based on the keratome bevel

Purpose: To evaluate differences in incision shape due to the bevel of the keratome. Setting: Kushimoto Rehabilitation Center. Kushimoto, Japan. Methods: Three types of keratomes (bibevel, bevel up, and bevel down) were inserted into soft polyvinyl chloride sheets and polyurethane sheets, and the incision shapes in the blade entrance and exit planes were evaluated. The experiments were repeated using soft polyvinyl chloride domes and silicone domes. Results: in the experiments using artificial sheets, the incisions in the blade entrance and exit planes using the bibevel keratome had a linear shape, those using the bevel-up keratome had an inverse-V shape, and those using the bevel-down keratome had a V shape. in the experiments using artificial domes, the incision shapes were the same as those in the artificial sheets. Conclusions: The incision shape differed according to the direction of the keratome bevel. These experiments and results may provide useful data when new knives are developed or when incision shapes following intended specifications are stably made.