Safety and efficacy of various concentrations of topical lidocaine gel for intravitreal injection

Abstract

Introduction: Intravitreal injection (IVT) is one of the most common vitreoretinal procedures, a large majority are performed with local anesthesia. the purpose of this study was to investigate the safety to the cornea and anesthetic efficacy of five concentrations of lidocaine gel.Methods: A prospective clinical trial was conducted testing lidocaine gel in five preparations: 2, 3.5, 5, 8 and 12%. Patients with macular degeneration, diabetic edema or retina vein occlusion were scheduled for intravitreal treatment received topical anesthesia with lidocaine gel 5 and 10 min before the procedure. Patients answered the visual analog scale for pain during the procedure. Corneal and conjunctival was evaluated using the Oxford scale.Results: in total, 260 patients were randomized into five groups. the mean pain scores (+/- standard deviation) were 2.63 (+/- 1.68) in the 2% group, 2.08 (+/- 1.35) in the 3.5%; 2.00 (+/- 1.65) in the 5%, 1.93 (+/- 1.40) in the 8% and 1.83 (+/- 1.35) in the 12% group. Mean pain score among all groups was similar (p = 0.077). There was no significant difference between groups in regard to keratitis mean score (p = 0.897).Conclusions: Lidocaine gel at concentrations from 2 to 12% induced similar anesthetic effect for IVTs, without adverse effects on cornea and conjunctiva.