Abstract
Purpose :
To evaluate intraocular pressure (IOP) change after cataract surgery in eyes with open angle glaucoma (OAG) and its relation to angle and anterior segment parameters measured by anterior segment optical coherence tomography (AS-OCT).
Methods :
In this prospective study, 81 eyes of 69 OAG patients underwent phacoemulsification and lens implantation. IOP and biometric parameters were measured by AS-OCT preoperatively and 4 months after surgery. The glaucoma medication regimen was kept the same after cataract surgery. Percentage of IOP change and its relation to biometric parameters, including anterior chamber depth (ACD), anterior chamber volume (ACV), iris thickness (IT), iris curvature, lens vault (LV), anterior chamber width (ACW), and angle parameters including angle opening distance (AOD 500 and AOD750) and trabecular iris space area (TISA500 and TISA750) were evaluated. The main outcome measure was percentage IOP change after phacoemulsification.
Results :
There were 71 patients with 81 eyes (21 male and 50 female) in our study with an overall mean age of 76.8±7.4 years. The average IOP reduction was −2.1±2.9 mmHg (12.8 %), from a preoperative mean of 15.0±3.4 mmHg, at 4 months after cataract surgery. In univariate linear regression, preoperative IOP (B=-2.755, p<001), AOD500 (B=45.177,p=0.03), AOD750 (B=35.701, p=0.01), and TISA500 (B=62.755, p=0.05) were significantly associated with percentage IOP decrease. Iris parameters, ACW, ACV, and ACD were not correlated with IOP drop. In multivariate analysis, higher preoperative IOP (B=-2.625, p<0.001) and AOD750 (B=42.752, p=0.001) were significantly associated with percentage IOP change (r2=0.40). Although preoperative IOP (p< 0.001, r2= 29 %) was a better predictor of percentage of IOP change, AOD750 can predict 14% of IOP change (p=0.003) after adjusting for age and gender.
Conclusions :
The percentage of IOP reduction after cataract surgery in eyes with open angle glaucoma is significantly greater in eyes with narrower angle and higher preoperative pressure. Combining angle parameters and preoperaive IOP can be helpful in predicting the amount of IOP drop in OAG patients.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.