Preservative-free lidocaine 1% anterior chamber irrigation as an adjunct to topical anesthesia

Purpose: To evaluate the effect on the central corneal endothelium of anterior chamber irrigation with preservative-free lidocaine 1% as an adjunct to topical anesthesia during phacoemulsification. Setting: Department of Ophthalmology, Hospital Capuchos, Lisbon, Portugal. Methods: This prospective, randomized, controlled study comprised 59 eyes. Thirty-one eyes had phacoemulsification (in-the-bag cracking technique) under topical anesthesia with anterior chamber irrigation by preservative-free lidocaine 1%. Twenty-eight eyes having the same procedure but with local-regional anesthesia served as the control group; All eyes had preoperative and postoperative specular microscopy and computer-assisted morphometry. A Student's t-test was used for between-group comparison of the following parameters: patient age, central corneal endothelial cell loss, mean endothelial cell size variation, and phacoemulsification ultrasound time. Follow-up was 4 weeks. Results: The between-group differences in mean patient age and ultrasound time were not significant. The differences between groups in the endothelial cell parameters were also not significant. Mean postoperative endothelial cell loss was 3.59% +/- 2.79 (SD) in the topical anesthesia group and 4.37 +/- 2.00% in the control group. Mean variation in cell size was 3.71 +/- 1.57% and 3.79 +/- 1.07%, respectively. Conclusion: Intracameral infusion of preservative-free lidocaine 1% had no effect on the corneal endothelial cell loss rate or mean cell size variation in this short-term assessment.