An Alternative Method of Phacoemulsification Surgery in Eyes with Functional Trabeculectomies

Abstract

Aims: To report success proportions in functional trabeculectomised eyes undergoing phaco-emulsifcation with a novel curvilinear capsulorhexis method. Methods: An observational series. Seventy two eyes of 72 patients were identified who underwent cataract surgery in eyes with functional prior trabeculectomy surgery using a Leweke cannula (cases). A previously reported group of 53 eyes in 53 patient who had routine cataract surgery (not using this technique) post-trabeculectomy surgery was used to compare outcomes (controls). Main outcome measure: The primary outcome measure was intraocular pressure (IOP) success (IOP ≤21, ≤18, ≤15 mmHg) at 5 years post cataract surgery. Complete success was no new medication or surgical intervention for IOP and partial success was additional medical therapy required to achieve the IOP target. Results: At final follow-up, the overall failure proportion of the combined groups for an IOP ≤21mmHg was 20% (24/125) at final review. Thirty percent who were a partial success prior to cataract surgery, failed in both controls and cases at final follow-up. Of those who were a complete success prior to phaco-emulsification; 33% were partial successes and 30% failed in the control group; 50% were partial successes and 10% failed in the case group, at final follow-up. Logistic regression for an outcome of failure showed the Leweke cannula to be protective OR 0.28 (95% CI 0.09 to 0.85, p=0.03). African/Caribbean ethnicity was a risk factor for failure. Conclusions: Our results suggest that cataract surgery may affect trabeculectomy outcomes, but not as profoundly as is currently perceived. Using the Leweke technique seems to result in earlier medication recommencement, but a strong reduction in the need for further surgical intervention in fully functional trabeculectomies.