Association of Gonioscopy Scores with Changes in Intraocular Pressure after Phacoemulsification in a Predominantly Vietnamese Population: A Retrospective Study.

Purpose: To evaluate the effectiveness of cataract extraction in reducing intraocular pressure (IOP) between high gonioscore and low gonioscore groups in a predominantly Vietnamese population. Patients and Methods: In this retrospective cohort study, we reviewed the records of patients who had cataract surgeries between Aug 2016-Sep 2019 at an ophthalmology clinic with a high volume of Vietnamese patients. The relationship between postoperative IOP and gonioscopy score (low [≤10] and high gonioscore [>10]) was evaluated. Results: There was a significant difference between the low and high gonioscore groups by age (low, 73.26 ± 8.34, high, 67.74 ± 9.10; p < 0.001), eyes with laser peripheral iridotomy (LPI) (low, n = 64 (42.1%), high, n = 5 (6.8%), p < 0.001), and anterior chamber depth (low, 2.89 ± 0.36, high, 3.18 ± 0.34; p < 0.001). The majority of eyes were from Vietnamese patients (n = 193, 85.4%). In an unadjusted model, there was a significant difference in absolute IOP at 6 months between the high and low gonioscore groups (low, 12.57 ± 2.85, high, 13.64 ± 3.20; p = 0.034). After adjustment, both gonioscore groups showed significant IOP reduction at 6-month follow-up, with higher IOP reduction in the low gonioscore group (p = 0.034). In the group-time interaction, there was a significant difference between low and high gonioscore groups at 6 months (Model 1, p = 0.033, Model 2, p = 0.044). Conclusion: We found a significant difference in IOP reduction at 6 months after cataract surgery between low and high gonioscore groups within a predominantly Vietnamese cohort. Given that IOP reduction can be achieved with cataract surgery to help minimize vision loss in glaucoma, gonioscopy can be a useful measure to predict post-surgical IOP in this population.