Effect of cataract surgery on aqueous turnover and blood-aqueous barrier

We evaluated changes in aqueous outflow and blood-aqueous barrier (BAB) disruption after cataract surgery in two randomly selected groups of eyes. In one group, a high-viscosity viscoelastic was used for intraocular lens (IOL) implantation; in the other, a low-viscosity viscoelastic. Fluorophotometry was used to evaluate aqueous humor dynamics five to seven hours after IOL implantation. Aqueous outflow after IOL implantation in operated eyes was nearly twice that in the fellow eyes, which served as controls. Mean protein concentration in the anterior chamber was also elevated in operated eyes. However, postoperative aqueous outflow did not differ significantly between the two groups. The substantial increase in aqueous outflow observed postoperatively and the increase in aqueous humor protein concentration were closely related to BAB disruption. These results suggest that BAB disruption may be a main cause of the transient high intraocular pressure observed after IOL implantation in both groups.