Evaluation of mechanical resistance to tearing of the anterior lens capsule after staining with different concentrations of trypan blue

Abstract

Purpose: To evaluate and compare the mechanical resistance to tearing of the anterior lens capsule opening after staining with different concentrations of trypan blue in ex vivo porcine eyes. Setting: Semmelweis University, and Budapest University of Technology and Economics, Budapest, Hungary. Design: Experimental study. Methods: The study comprised 75 porcine eyes. The capsule was unstained in the Control Group (n = 25 eyes), 0.06% trypan blue was used to stain the capsule in Stained 1 Group (n = 25 eyes), and 0.1% trypan blue was used to stain the capsule in Stained 2 Group (n = 25 eyes). After capsulorhexis, the capsule openings were stretched with custom-designed testing equipment until they ruptured. The rupture force (RF), circumference stretching ratio (CSR), and secant modulus at 10 mN (SM10mN) and 50 mN (SM50mN) were evaluated. Results: In total, 75 eyes were enrolled. There were no statistically significant differences in the RF (P = .8924) or CSR (P = .3876) among the groups. There were no statistically significant differences in the SM10mN (P = .8215) or SM50mN (P = .4184) among the groups. Conclusions: In this porcine eye model, the trypan blue concentrations that are routinely used in cataract surgery had no effect on capsular rim stability.