Factors affecting changes in the intraocular pressure after phacoemulsification surgery

AIM: To assess the changes in anterior chamber parameters and examine the factors associated with changes in the intraocular pressure(IOP)in individuals who have undergone phacoemulsification surgery.METHODS: It was a longitudinal analysis of secondary clinical data collected from 105 non-glaucomatous eyes(of 82 patients)undergoing a cataract surgery. We studied the association between anterior chamber parameters, grade of cataract, demographics, and changes in the IOP over a period of 3wk. We also evaluated the association between the pressure-depth(PD)ratio and changes in the IOP during this time.RESULTS: The mean age [standard deviation(SD)] of the 82 patients was 60.1(7.8)years. The mean SD IOP was 15.06(3.36)mmHg pre-operatively; it increased to 15.75(4.21)mmHg on day one(P=0.20). In the multifactorial models, the mean IOP was -1.715 \〖95% confidence intervals(CI): -2.795, -0.636\〗 mmHg on day 21(±5)compared with the pre-operative values. The anterior chamber depth(ACD), axial length, age, sex, and grade of cataract were not significantly associated with changes in the IOP. Each unit increase in the PD ratio was associated with an increase in the mean IOP by 1.289 mmHg(95% CI: 0.906, 1.671). After adjusting for pre-operative PD ratio, none of the other variables(ACD, axial length, temporal angle)were significantly associated with changes in mean IOP.CONCLUSION: The PD ratio was the single most important factor associated with the changes in post-operative IOP over 3wk post surgery