Intraocular Pressure after Phacoemulsification with Retained Lens Fragments in the IRIS® Registry (Intelligent Research in Sight)

Purpose: To describe intraocular pressure (IOP) changes after cataract surgery resulting in retained lens fragments (RLFs).

Design: Retrospective clinical cohort study.

Participants: Eyes in the IRIS® Registry (Intelligent Research in Sight) that underwent stand-alone phacoemulsification resulting in RLFs.

Methods: Daily mean IOP was calculated from postoperative days 1 through 90. An IOP spike was defined as a daily mean IOP > 30 mmHg and > 10 mmHg above baseline IOP within the first postoperative week. A linear mixed model determined when the postoperative daily mean IOP stabilized, and a final mean IOP was calculated by averaging the final daily mean IOP for all eyes from that time point onward. Odds ratios (ORs) with 95% confidence intervals (CIs) for demographic and clinical characteristics were calculated with univariable and multivariable logistic regression analyses. Eyes were censored on additional intervention that could affect IOP such as secondary surgery or addition of IOP-lowering medication.

Main outcome measures: Postoperative daily mean IOP and incidence and OR of IOP spike.

Results: Retained lens fragments were noted in 6105 eyes with mean (standard deviation [SD]) baseline IOP of 15.8 (3.6) mmHg. An initial elevation in daily mean (SD) IOP after cataract surgery to 21.2 (8.5) mmHg was noted that gradually declined but remained above baseline IOP until postoperative day 14. The final mean (SD) IOP and weeks until IOP stabilization were 15.0 (4.1) mmHg at 5 weeks. An IOP spike occurred in 766 eyes (12.5%). Factors associated with IOP spike include male sex (OR, 1.47; 95% CI, 1.28-1.70; P < 0.0001), higher baseline IOP (OR, 1.24 per 3 mmHg; 95% CI, 1.18-1.31 per 3 mmHg; P < 0.0001), and glaucoma diagnosis (OR, 1.18; 95% CI, 1.01-1.39; P = 0.038).

Conclusions: The initial IOP elevation after phacoemulsification resulting in RLFs is higher than after standard cataract surgery because of an increased incidence of IOP spike. Surgeons should be more vigilant for possible IOP spikes in eyes with higher baseline IOP, male sex, and glaucoma. Eyes without an indication for secondary intervention will show a gradual IOP return to baseline level that will stabilize after an average of 5 weeks.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.