BACKGROUND: This study investigated the efficacy and safety of intracameral injection of commercially available eye drops containing 0.5% tropicamide and 0.5% phenylephrine hydrochloride (Mydrin-P, Santen Pharmaceutical, Osaka, Japan). DESIGN: In vitro experiment and prospective clinical study at a private hospital. PARTICIPANTS AND SAMPLES: Mydrin-P was applied to confluent cultured human corneal endothelial cells, and the cellular morphology was examined. Clinical study subjects were 65 eyes of 65 patients that underwent phaco-emulsification and aspiration with intraocular lens implantation and received intracameral injection of Mydrin-P for poor mydriasis after preoperative topical instillation of mydriatics (intraocular mydriasis group; with five subgroups based on cause: diabetes, pseudo-exfoliation, post-surgery, uveitis, unknown). Controls, comprising 39 eyes of 39 patients, were not injected with Mydrin-P. METHODS: The ratio of pupillary diameter to corneal diameter was determined before and after injection of Mydrin-P. Corneal endothelial density was measured preoperatively and 3 months and 1 year postoperatively. MAIN OUTCOME MEASURES: Pupillary diameter and corneal endothelial density. RESULTS: Human corneal endothelial cell morphology was unaltered after Mydrin-P injection. The mean ratio of the pupillary diameter to corneal diameter increased in the intraocular mydriasis group (before: 54.2 ± 4.8%, after: 58.4 ± 6.6%; P < 0.001) and in the diabetes and unknown subgroups. The corneal endothelial cell density reduction rate 3 months and 1 year after surgery was not significantly different between the intraocular mydriasis group and controls. CONCLUSION: Intracameral injection of Mydrin-P appears to be effective and safe for dilating the pupil in cases with poor mydriasis after preoperative instillation of mydriatics.
BACKGROUND: This study investigated the efficacy and safety of intracameral injection of commercially available eye drops containing 0.5% tropicamide and 0.5% phenylephrine hydrochloride (Mydrin-P, Santen Pharmaceutical, Osaka, Japan). DESIGN: In vitro experiment and prospective clinical study at a private hospital. PARTICIPANTS AND SAMPLES: Mydrin-P was applied to confluent cultured human corneal endothelial cells, and the cellular morphology was examined. Clinical study subjects were 65 eyes of 65 patients that underwent phaco-emulsification and aspiration with intraocular lens implantation and received intracameral injection of Mydrin-P for poor mydriasis after preoperative topical instillation of mydriatics (intraocular mydriasis group; with five subgroups based on cause: diabetes, pseudo-exfoliation, post-surgery, uveitis, unknown). Controls, comprising 39 eyes of 39 patients, were not injected with Mydrin-P. METHODS: The ratio of pupillary diameter to corneal diameter was determined before and after injection of Mydrin-P. Corneal endothelial density was measured preoperatively and 3 months and 1 year postoperatively. MAIN OUTCOME MEASURES: Pupillary diameter and corneal endothelial density. RESULTS: Human corneal endothelial cell morphology was unaltered after Mydrin-P injection. The mean ratio of the pupillary diameter to corneal diameter increased in the intraocular mydriasis group (before: 54.2 ± 4.8%, after: 58.4 ± 6.6%; P < 0.001) and in the diabetes and unknown subgroups. The corneal endothelial cell density reduction rate 3 months and 1 year after surgery was not significantly different between the intraocular mydriasis group and controls. CONCLUSION: Intracameral injection of Mydrin-P appears to be effective and safe for dilating the pupil in cases with poor mydriasis after preoperative instillation of mydriatics.
Authors: Paolo Nucci; Andrea Lembo; Roberto Caputo; Andrea Dellavalle; Massimiliano Serafino; Irene Schiavetti; Francesco Pichi Journal: Int Ophthalmol Date: 2022-09-02 Impact factor: 2.029