Long-term effect of cataract surgery on intraocular pressure after trabeculectomy: extracapsular extraction versus phacoemulsification.

Purpose: To compare the effect of phacoemulsification with intraocular lens (IOL) implantation on long-term intraocular pressure (IOP) control in glaucoma patients who had previous trabeculectomy with the effect on IOP control in similar patients after extracapsular cataract extraction (ECCE) with IOL implantation.

Setting: Oxford Eye Hospital, Oxford, England.

Methods: Twenty-eight consecutive patients who had phacoemulsification with IOL implantation (phaco group) at least 3 months after trabeculectomy were identified from hospital records, and 28 patients who had ECCE with IOL implantation (ECCE group) were matched retrospectively to the phaco group with respect to age, sex, diagnosis, and IOP. In both groups, the IOP before cataract extraction was compared with the IOP at intervals up to 2 years after cataract extraction. A Kaplan-Meier survival analysis was performed.

Results: The mean IOP in the phaco group did not differ significantly from the mean IOP before cataract extraction at any interval. Twelve months after cataract extraction, the mean IOP in the ECCE group was significantly higher than preoperatively (P =.01); however, the mean IOP did not differ between groups over time (P =.704). There was significantly better long-term IOP control in the phaco group as determined by Kaplan-Meier survival analysis and the log-rank test (P =.038).

Conclusion: After trabeculectomy, phacoemulsification provided better long-term IOP control than ECCE; however, the mean IOP was not significantly lower.