PURPOSE:
To determine predictors of long-term intraocular pressure (IOP) after cataract surgery.
SETTING:
Hunter Holmes McGuire Veterans Administration Hospital, Richmond, Virginia, USA.
DESIGN:
Case series.
METHODS:
Clinical variables, IOP by applanation tonometry, anatomic features on anterior segment optical coherence tomography (AS-OCT), and gonioscopy were assessed before and after uneventful cataract surgery in eyes with open filtration angles. Multivariate linear regression of preoperative measurements was used to predict the mean IOP from 2 to 18 months postoperatively.
RESULTS:
The study enrolled 77 eyes (77 patients). Prediction of the mean postoperative IOP improved when up to 4 preoperative IOP values were averaged (r2 = 0.20) compared with using the final preoperative IOP value only (r2 = 0.13). The mean iris cross-sectional area decreased after surgery, from 3.84 mm2 to 3.70 mm2 (P=.01). The mean convex hull of the iris segments also decreased, from 5.05 mm2 to 4.19 mm2 (P<.001). The mean postoperative IOP was independently predicted by the preoperative average IOP, primary open-angle glaucoma, and the convex hull of cross-sectional iris segments (P=.001, model r2 = 0.38) or iris cross-sectional area (P=.003, model r2 = 0.36). Phacoemulsification parameters, incision type, and anterior chamber angle and depth did not predict postoperative IOP.
CONCLUSIONS:
Averaging up to 4 preoperative IOP values improved postoperative IOP predictions. A high iris cross-sectional area or convex hull of the iris segments on AS-OCT was associated with lower postoperative IOP. These findings might help identify patients who are likely to have the largest IOP drop after cataract surgery.
Financial Disclosure:
No author has a financial or proprietary interest in any material or method mentioned.
