Pharmacologic prevention of posterior capsule opacification: in vitro effects of preservative-free lidocaine 1\\% on lens epithelial cells

Abstract

The toxicity of preservative-free lidocaine 1% to lens epithelial cells (LECs) and its efficacy in removing LECS from the anterior lens capsule were evaluated. Sixteen postmortem rabbit eyes were divided into two groups. In group 1 (n = 8 eyes), LECS were exposed to preservative-free lidocaine 1% or balanced salt solution (BSS) for 1, 2, or 5 minutes. The anterior capsules were then stained with trypan blue and alizarin red. Photomicrographs of each capsule were taken and analyzed for LEC damage. Anterior capsule fragments irrigated with preservative-free lidocaine 1% showed mild LEC toxicity; i.e., some cells showed blue nuclear staining. Those irrigated with BSS had no evidence no evidence of LEC toxicity, i.e., no nuclear staining. In group 2 (n= 8 eyes), hydrodissection was performed with preservative-free lidocaine 1% (n= 4 eyes) or BSS (n= 4 eyes) followed by phacoemulsification and cortical cleanup. The LEC attachment to the anterior capsule was evaluated by histopathology. After hydrodissection with preservative-free lidocaine 1%, the capsules were almost free of LECs. After hydrodissection with BSS, the capsules showed a normal layer of LECs attached to the anterior capsule. Preservative-free lidocaine may help prevent posterior capsule opacification by diminishing the amount of live LECs retained in the anterior lens capsule. Michael D.Wagoner