Efficacy of 0.1% Topical Nepafenac in Maintaining Transoperative Mydriasis and Preventing Postoperative Macular Oedema in Phacoemulsification Cataract Surgery: A Research Protocol

Introduction: Following standard cataract surgery, postoperative Cystoid Macular Oedema (CMO) may result in visual impairment. Currently, phacoemulsification is considered the best surgical technique for cataract extraction due to the superior visual outcomes achieved after Intraocular Lens (IOL) implantation. Despite advancements in surgical techniques and improvements in IOL materials over the past decade, there remains a risk of unintentional ocular injury during surgery. Need of the study: Miosis during cataract surgery can hinder surgical access and visualisation, increasing the likelihood of complications. It is caused by the release of Prostaglandins (PGs) triggered by surgical trauma, which stimulates contraction of the iris sphincter muscle. Nepafenac, a Non Steroidal AntiInflammatory Drug (NSAID), inhibits Cyclooxygenase (COX), thereby reducing PG synthesis and preventing miosis when administered prophylactically before surgery. Maintaining adequate mydriasis ensures better surgical access and reduces intraoperative risks. Additionally, nepafenac’s anti-inflammatory properties help reduce the incidence of macular oedema—a postoperative complication arising from inflammation and disruption of the blood-retinal barrier. Aim: To evaluate the effectiveness of prophylactic topical nepafenac 0.1% in maintaining intraoperative mydriasis and preventing postoperative macular oedema in patients undergoing topical phacoemulsification cataract surgery. Materials and Methods: A prospective, randomised, singlemasked comparative study will be conducted from June 2024 to June 2026 in the Ophthalmology Outpatient Department at Acharya Vinobha Bhave Rural Hospital (AVBRH), Sawangi, Meghe, Maharashtra, India. A total of 38 patients undergoing phacoemulsification cataract surgery will be equally divided into two groups (n=19 each). All patients will receive two doses of tropicamide 0.8% and phenylephrine 5% at 15-minute intervals. The experimental group will additionally receive nepafenac 0.1%— four doses administered hourly before surgery and three times daily for six weeks postoperatively. The control group will receive only prednisolone and moxifloxacin eye drops in a 15-day tapering regimen. Postoperative assessments will include Best-Corrected Visual Acuity (BCVA), Intraocular Pressure (IOP), fundoscopy, slit lamp evaluation of cells and flare and macular Optical Coherence Tomography (OCT) at two and six weeks. Statistical analysis will include descriptive tests, Chi-square test and Fisher’s-exact test to determine associations among clinical and demographic variables.