Intracameral lidocaine anaesthesia for cataract surgery: Effectiveness and safety of application during hydrodissection

Objective: Topical anaesthesia has been proven to be safe and effective in controlling pain during routine cataract surgery. However, pain sensations cannot be completely excluded during certain steps of the procedure. The aim of this study was to evaluate the effect of unpreserved lidocaine 1% administered during hydrodissection on intraoperative pain levels. Possible local toxic effects on the corneal endothelium were assessed comparing pre- and post-operative central corneal endothelial cell counts. Patients and methods: This prospective, double-masked, placebo-controlled trial was conducted at the Medical Universities of Vienna and Innsbruck. In total, 158 eyes (100 in Vienna, 58 in Innsbruck) were included. Patients were randomly assigned to two groups receiving either unpreserved lidocaine 1% intracamerally during hydrodissection or balanced salt solution (BSS). Patients were questioned about intraoperative pain sensations at six time points during cataract surgery and subjective pain scores were quantified using a 6-step grading scale. Central corneal endothelial cell densities were recorded with an endothelial specular microscope before and 3 months after surgery and endothelial cell loss was calculated. Results: There was no statistical difference in painscores between the lidocain 1%-group and the BSS-group at any measured time point. Mean postoperative endothelial cell loss after three months was 2% in the lidocaine 1%-group and 3% in the group treated with BSS (p = 0,28). Conclusion: Intracameral injection of unpreserved lidocaine 1% during hydrodissection was not effective in reducing intraoperative pain compared to a control group receiving BSS. Since painscores were very low intracameral lidocaine was not found to be of benefit in standard cataract surgery. Local toxic effects on the central corneal endothelium could not be found. © Springer-Verlag 2008.