Intra-ocular pressure fluctuation after cataract surgery in primary angle-closure glaucoma eyes medically controlled after laser iridotomy.

Purpose To analyse the effect of cataract surgery on diurnal intra-ocular pressure (IOP) fluctuation in primary angle-closure glaucoma (PACG) eyes. Methods Thirty-nine eyes of 24 patients with PACG scheduled for cataract surgery were enrolled to this prospective study. A record was made which included mean IOP measurement, anterior chamber depth (ACD), anterior chamber angle (ACA), number of antiglaucomatous medications, visual field analysis (mean deviation – MD and pattern standard deviation – PSD) and responses to the Glaucoma Quality of Life-15 (GQL-15) questionnaires. The eyes were re-evaluated at 2 and 3 months of cataract surgery. Results IOP fluctuation was decreased from 4.58 ± 2.07 mmHg to 2.84 ± 1.5 mmHg (p < 0.001). The decrease in mean IOP, the number of glaucoma eye drops required (p < 0.001, p = 0.012, respectively) and the increase in mean ACD, ACA grading and SITA-standard MD (p < 0.001, p < 0.001, and p = 0.01, respectively) were statistically significant. The mean GQL-15 score was also improved (p < 0.001). The change in IOP fluctuation correlated positively with the preoperative IOP fluctuation (r = 0.56 p = 0.00), the change in ACD (r = 0.703, p < 0.001) and the change in ACA (r = 0.664, p < 0.001). In multivariate analysis, preoperative IOP fluctuation and postoperative increase in ACD were significantly associated with a reduction in IOP fluctuation of an average of 1.1 mmHg per unit change (p = 0.00 and p = 0.019, respectively). Conclusions Cataract surgery in PACG provides the opportunity to address many pathologies with one intervention; improving vision, diminishing IOP, blunting IOP fluctuation, reducing need for medications, eliminating a narrow angle and improving GQL-15 scores.