Trabeculotomy versus combined trabeculotomy-trabeculectomy for primary congenital glaucoma: study protocol of a randomised controlled trial

Introduction Trabeculotomy and combined trabeculotomy-trabeculectomy (CTT) are major surgical options for primary congenital glaucoma (PCG). However, it is unclear which of these two surgical procedures should be recommended as the optimum first-line treatment for PCG. This trial aims to determine whether the outcomes of trabeculotomy are non-inferior to those of CTT in moderate PCG with a horizontal corneal diameter (HCD) of 12-14 mm. Methods and analysis This is a 3-year, non-inferiority, prospective, randomised controlled trial. We plan to recruite 248 participants (aged <= 3 years) with PCG with an HCD of 12-14 mm from the Department of Glaucoma, Zhongshan Ophthalmic Center, Guangzhou, China. One eye per participant will be randomly (1:1) assigned to receive trabeculotomy or CTT. The primary outcome is the 3-year postoperative success rate in lowering intraocular pressure (IOP), and the secondary clinical outcomes will include IOP reduction, visual acuity, HCD, central corneal thickness, axial length, cup-disc ratio, refractive error and postoperative complications. Data will be analysed by the intention-to-treat principle.