The outcome of the functioning filter after subsequent cataract extraction

Area of Science:

• Ophthalmology
• Glaucoma Surgery
• Cataract Surgery

Background:

• Trabeculectomy is a common filtration surgery for glaucoma.
• Cataract surgery following trabeculectomy can impact intraocular pressure (IOP) control.
• Phacoemulsification and extracapsular cataract extraction (ECCE) are two techniques for cataract removal.

Purpose of the Study:

• To compare the outcomes of phacoemulsification versus ECCE for cataract surgery in glaucomatous eyes with functioning trabeculectomies.
• To evaluate the impact of cataract surgery on IOP control after successful filtration surgery.

Main Methods:

• Retrospective evaluation of 77 eyes (68 patients) that underwent cataract surgery after successful trabeculectomy.
• Categorization of IOP control failure into partial (increased medications/laser) and complete (IOP >21 mmHg or re-operation).
• Kaplan-Meier analysis for failure rates and log-rank test for subgroup comparison.

Main Results:

• No statistically significant difference in partial failure rates (39.5% phacoemulsification vs. 37.3% ECCE) by year 3.
• No statistically significant difference in complete failure rates (12.0% phacoemulsification vs. 12.5% ECCE) by year 4.
• Visual acuity improved in 87% of patients; 61% achieved 20/40 or better. Posterior capsular opacification occurred in 31.2%.

Conclusions:

• Cataract extraction by phacoemulsification or ECCE after trabeculectomy may compromise IOP control.
• Increased antiglaucoma medication or further interventions may be necessary post-cataract surgery.
• Both techniques appear comparable in terms of IOP control impact and visual outcomes.