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.