A Comparative Study of the Duration and Efficacy of Tetracaine 1% and Bupivacaine 0.75% in Controlling Pain following Photorefractive Keratectomy (PRK)

Abstract

Objective To evaluate if topical bupivacaine 0.75% provides better pain control after excimer laser over topical tetracaine 1% without affecting corneal wound healing, refractive outcome of visual function. Design A prospective, double-masked trial was conducted in which 38 patients were randomized to receive either tetracaine or bupivacaine every 30 minutes for 24 hours post-operatively. Pain was recorded over a four day period using a Visual Analogue Pain Scale. The rate of epithelial healing was assessed during digitized retro-illumination photography. Visual performance was recorded using best corrected Snellen acuity, objective measurements of haze, halo and glare over a six month period. Results Tetracaine afforded better pain control (p=0.05). Full epithelial closure occurred in all patients within 72 hours and no statistically significant difference was recorded in any of the parameters measured. Conclusions Contrary to our expectation, the longer acting anaesthetic, bupivacaine, was inferior to tetracaine. Limited and supervised use of topical anaesthetics is recommended in controlling pain following photorefractive keratectomy.