Aqueous humor outflow and intraocular drug transport through trabecular and uveoscleral pathways

Accurately predicting the temporal and spatial distribution of intraocular drugs to enhance anti-glaucoma treatment efficacy remains a significant challenge in clinical ophthalmology. Developing more precise numerical models of intraocular drug transport holds substantial clinical value. This study establishes a model of intraocular drug transport, which includes the trabecular meshwork (TM), collector channels (CC), and uveoscleral outflow pathway, and analyzes the parameters affecting aqueous humor (AH) outflow and the impact of the uveoscleral pathway on drug transport. Results indicate that the uveoscleral pathway influences AH outflow, with its porous media significantly impeding drug clearance, leading to drug accumulation in the anterior chamber and higher concentrations in the TM. A reduction in TM porosity or the number of CC hinders drug transport to varying extents, increasing peak drug concentration at TM targets by 11.27% and 12.8%, respectively. Furthermore, neglecting the uveoscleral pathway may result in an 10.93% underestimation of TM drug concentration. This study provides insight into the pathways involved in anti-glaucoma drug transport, contributing to the optimization of drug design for improved therapeutic outcomes.