[The effect of phacoemulsification of age-related cataract on intraocular pressure and iridocorneal angle parameters...

Cataract phacoemulsification with intraocular lens implantation significantly affects the morphology of the anterior chamber angle (ACA) and contributes to a reduction of intraocular pressure (IOP).

This study investigates the changes in anterior chamber angle configuration and IOP level before and after cataract surgery in primary open-angle glaucoma (POAG) eyes, and assesses its possible relationship with the axial length of the eye.

The study included 38 patients with immature senile cataract and compensated unoperated stage I-II POAG. Patients underwent anterior segment optical coherence tomography (AS-OCT) with measurement of the angle opening distance (AOD₇₅₀) and trabecular-iris space area (TISA₇₅₀) before and six weeks after the surgery, as well as axial length and corneal-compensated IOP (IOP_cc).

After the surgery 92.11% of patients showed a decrease in IOP_cc an average of 1.84±1.95 mm Hg (by 12.33±10.21% of the baseline); the maximum decrease in the IOP_cc level was 8.35 mm Hg (by 40.97% of the baseline). AS-OCT data indicates that cataract phacoemulsification causes an increase in anterior chamber angle width: AOD₇₅₀ increased from 0.510±0.175 to 0.771±0.156 mm, and TISA₇₅₀ increased from 0.266±0.090 to 0.494±0.096 mm². The strongest correlations were found between the axial length, postoperative TISA₇₅₀ increase (Δ%TISA₇₅₀) and postoperative IOP_cc reduction (Δ% IOP_cc). Postoperatively, specific changes could be observed in the trabecular meshwork in 28.95% of cases in the form of elongation and strain of the membrane.

Cataract extraction contributes to a significant reduction in IOP due to anterior chamber angle expansion, trabecular meshwork stretching, and improved aqueous outflow.