This randomized controlled trial evaluated the effect of trypan blue on corneal endothelial cell count in patients undergoing phacoemulsification for age-related cataract. Sixty participants were randomly assigned to undergo phacoemulsification either with trypan blue-assisted anterior capsule staining or without trypan blue. The primary objective was to compare postoperative corneal endothelial cell count between the two groups using specular microscopy to determine whether trypan blue has an effect on corneal endothelial cell loss during cataract surgery.